JP2012215174A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of a scroll compressor by securely supplying oil to a bearing part.SOLUTION: A bearing oil supply passage (70) for supplying refrigerator oil from an oil sump (18) inside a casing (15) to a bearing of a drive shaft (60) is formed in this scroll compressor (10). An oil groove (80) that communicates only with the oil sump (18) inside the casing (15) via a connecting passage (86) and a capillary tube (87) is formed in the thrust sliding surface (35) on the stationary side of the stationary scroll (30). Since the bearing oil supply passage (70) and the oil groove (80) are not communicated with each other, even if the moveable scroll (40) tilts and the pressure in the oil groove (80) decreases, the pressure in the bearing oil supply passage (70) does not decrease, and the refrigerator oil is supplied from the bearing oil supply passage (70) to the bearing of the drive shaft (60).

Description

  The present invention relates to a measure for improving the reliability of a scroll compressor.

  Conventionally, scroll compressors are widely used for compressing refrigerant, air, and the like. For example, Patent Document 1 discloses a hermetic scroll compressor. Here, the structure of the scroll compressor (500) disclosed in Patent Document 1 will be described with reference to FIG.

  In the scroll compressor (500), a compression mechanism (520) and an electric motor (515) are accommodated in a vertically long cylindrical casing (510). The compression mechanism (520) is disposed above the electric motor (515) and is connected to the electric motor (515) via the drive shaft (550).

  The compression mechanism (520) includes a fixed scroll (525), a movable scroll (530), and a housing (540). In the end plate portion (531) of the movable scroll (530), a wrap (532) protrudes from the front surface, and a cylindrical portion (533) protrudes from the rear surface. In the compression mechanism (520), the wrap (532) of the movable scroll (530) meshes with the wrap (526) of the fixed scroll (525) to form the compression chamber (521). Further, the thrust sliding surface (536) of the end plate portion (531) of the movable scroll (530) is in sliding contact with the thrust sliding surface (527) of the fixed scroll (525). The eccentric part (551) of the drive shaft (550) is inserted into the cylindrical part (533) of the movable scroll (530). When the drive shaft (550) rotates, the movable scroll (530) performs a revolving motion, and the refrigerant sucked into the compression chamber (521) is compressed.

  In this scroll compressor (500), an oil supply passage (555) is formed in the drive shaft (550). Lubricating oil that has flowed into the oil supply passage (555) from the bottom of the casing (510) is supplied to the bearing portion from the first branch passage (556) and the second branch passage (557). Further, a part of the lubricating oil flowing through the oil supply passage (555) flows out from the end of the oil supply passage (555) opened at the upper end of the eccentric portion (551).

  The refrigerant pressure in the compression chamber (521) acts on the front surface of the end plate portion (531) of the movable scroll (530). For this reason, when the refrigerant | coolant pressure in a compression chamber (521) rises, the movable scroll (530) will be pushed down and the airtightness of a compression chamber (521) will fall.

  On the other hand, in the scroll compressor (500), a seal ring (541) is provided between the housing (540) and the movable scroll (530). The pressure inside the seal ring (541) is substantially equal to the pressure of the lubricating oil flowing out from the end of the oil supply passageway (555) (and hence the pressure of the refrigerant discharged from the compression mechanism (520)). For this reason, the movable scroll (530) is pushed upward by the pressure acting on the back surface of the end plate portion (531). As a result, the movable scroll (530) is pressed against the fixed scroll (525), and the airtightness of the compression chamber (521) is ensured.

  However, the force that the movable scroll (530) presses against the fixed scroll (525) may become too strong. If this force becomes too strong, the frictional force generated on the thrust sliding surface (536) of the movable scroll (530) and the thrust sliding surface (527) of the fixed scroll (525) will increase, resulting in consumption of the electric motor (515). Power will increase.

  On the other hand, in the scroll compressor (500), an oil groove (534) and a communication path (535) are formed in the end plate portion (531) of the movable scroll (530). The oil groove (534) is a concave groove that opens to the thrust sliding surface (536) of the end plate portion (531), and is formed so as to surround the periphery of the wrap (532).

  The oil groove (534) communicates with the internal space of the cylindrical portion (533) via the communication path (535). Accordingly, the pressure in the oil groove (534) is substantially equal to the pressure of the lubricating oil flowing out from the end of the oil supply passage (555). The pressure in the compression chamber (521) adjacent to the oil groove (534) is approximately the same as the pressure of the low-pressure refrigerant sucked into the compression chamber (521), and is lower than the pressure in the oil groove (534). For this reason, a sufficient amount of lubricating oil is supplied to the thrust sliding surfaces (527,536) due to the pressure difference between the oil groove (534) and the compression chamber (521). As a result, the frictional force generated on the thrust sliding surface (536) of the movable scroll (530) and the thrust sliding surface (527) of the fixed scroll (525) is reduced, and the power consumption of the electric motor (515) can be kept low. .

Japanese Patent No. 3731068

  In the movable scroll (530) of the scroll compressor (500), the internal pressure of the compression chamber (521) acts on the wrap (532) protruding from the front surface of the end plate portion (531) and protrudes from the back surface of the end plate portion (531). A load from the drive shaft (550) acts on the cylindrical portion (533). The gas pressure acting on the wrap (532) and the load acting on the cylindrical portion (533) have their lines of action perpendicular to the axial direction of the movable scroll (530) and do not cross each other. For this reason, a moment to tilt the movable scroll (530) acts on the movable scroll (530).

  If the pressure acting on the back of the end plate (531) (specifically, the pressure inside the seal ring (541)) is sufficiently high, the movable scroll (530) is strongly pressed against the fixed scroll (525). The movable scroll (530) does not tilt even when a moment is applied. However, in an operating state where the pressure acting on the back surface of the end plate (531) is not so high (for example, an operating state where the pressure of the refrigerant discharged from the compression mechanism (520) is very low), the movable scroll (530) is tilted. The clearance between the thrust sliding surface (536) of the movable scroll (530) and the thrust sliding surface (527) of the fixed scroll (525) may increase. In the scroll compressor (500) shown in FIG. 9, when the clearance of the thrust sliding surfaces (527, 536) is increased, the pressure in the oil groove (534) may be rapidly decreased.

  In the conventional scroll compressor (500) shown in FIG. 9, the oil groove (534) communicates with the bearing portion of the compression mechanism (520) via the communication path (535) and the oil supply path (555). For this reason, when the movable scroll (530) is tilted and the pressure in the oil groove (534) rapidly decreases, the pressure in the oil supply passage (555) communicating with the oil groove (534) decreases, and the lubricating oil flows from the bearing portion. There is a risk of backflow through the branch passage (556,557) to the oil supply passage (555). Then, if the lubricating oil flows backward from the bearing portion to the oil supply passageway (555), the bearing portion is not sufficiently lubricated, which may cause troubles such as seizure.

  This invention is made | formed in view of this point, The objective is to improve the reliability of a scroll compressor.

  1st invention is accommodated in the casing (15), the compression mechanism (20) which is accommodated in this casing (15), and has a fixed scroll (30) and a movable scroll (40), The said casing (15), A drive shaft (60) engaged with the movable scroll (40), and the compression mechanism (20) discharges the compressed fluid into the casing (15), and the movable scroll (40) The present invention is directed to a scroll compressor configured to generate a pressing force for pressing against a fixed scroll (30). The end plate portion (41) of the movable scroll (40) and the fixed scroll (30) are formed with a movable thrust sliding surface (45) and a fixed thrust sliding surface (35) that are in sliding contact with each other. The movable thrust sliding surface (45) or the fixed thrust sliding surface (35) is formed with an oil groove (80) through which lubricating oil flows, and is not in communication with the oil groove (80). A bearing oil supply passage (70) for supplying lubricating oil in an oil reservoir (18) in the casing (15) to a bearing of the drive shaft (60) provided in the compression mechanism (20); A groove communication path (85) for connecting the oil groove (80) to the oil reservoir (18) in the casing (15) is provided.

  In the first invention, when the movable scroll (40) is driven by the drive shaft (60), fluid is sucked into the compression mechanism (20) and compressed. The compression mechanism (20) discharges the compressed fluid into the casing (15). For this reason, the pressure of the lubricating oil stored in the casing (15) is substantially equal to the pressure of the fluid discharged from the compression mechanism (20). The lubricating oil in the casing (15) is supplied to the bearing of the compression mechanism (20) through the bearing oil supply passage (70).

  In the compression mechanism (20) of the first invention, the movable scroll (40) is pressed against the fixed scroll (30) in order to ensure the airtightness of the compression chamber. Further, the movable side thrust sliding surface (45) of the movable scroll (40) and the fixed side thrust sliding surface (35) of the fixed scroll (30) slide with each other. In the compression mechanism (20), an oil groove (80) is formed on the movable thrust sliding surface (45) or the fixed thrust sliding surface (35). The oil groove (80) communicates with the oil reservoir (18) in the casing (15) through the groove communication path (85). For this reason, the pressure of the lubricating oil in the oil groove (80) becomes substantially equal to the pressure of the lubricating oil stored in the casing (15). The lubricating oil that has flowed from the oil reservoir (18) through the groove communication passage (85) into the oil groove (80) is supplied to the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). The

  In the compression mechanism (20) of the first invention, the movable scroll (40) may tilt. In this case, the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) increases, and as a result, the pressure in the oil groove (80) may drop rapidly. On the other hand, in the present invention, the bearing oil supply passage (70) is not in communication with the oil groove (80). For this reason, even if the pressure in the oil groove (80) drops rapidly, the pressure in the bearing oil supply passage (70) does not change.

  In a second aspect based on the first aspect, the bearing oil supply passage (70) is driven by the drive shaft (60), and lubricating oil is supplied from an oil reservoir (18) in the casing (15). An oil supply pump (75) that sucks and discharges is provided, and the groove communication passage (85) receives lubricating oil only by the pressure difference between the oil reservoir (18) in the casing (15) and the oil groove (80). It is configured to be distributed.

  In the second aspect of the invention, when the movable scroll (40) is tilted during operation of the compression mechanism (20) and the pressure in the oil groove (80) decreases, the lubricating oil in the oil sump (18) is contained in the casing (15). Due to the pressure difference between the oil sump (18) and the oil groove (80), it flows through the groove communication passage (85) toward the oil groove (80). On the other hand, an oil supply pump (75) is provided in the bearing oil supply passage (70). The oil supply pump (75) is driven by the drive shaft (60), and sucks and discharges the lubricating oil from the oil reservoir (18) in the casing (15). Lubricating oil discharged from the oil supply pump (75) is supplied to the bearing of the compression mechanism (20).

  In a third aspect based on the second aspect, the groove communication passage (85) is provided with a throttle portion for restricting the flow rate of the lubricating oil.

  If the movable scroll (40) tilts during the operation of the compression mechanism (20), the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) increases. For this reason, the lubricating oil tends to flow out from the oil groove (80), and the flow rate of the lubricating oil in the groove communication path (85) may be excessive.

  On the other hand, in the third invention, the throttle portion is provided in the groove communication path (85). Even in the state where the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) is enlarged, the flow rate of the lubricating oil in the groove communication passage (85) is limited by the throttle portion.

  In a fourth aspect based on the third aspect, the throttle portion is inserted into the groove communication passage (85), and has a rod shape in which a spiral groove (89e) for flowing lubricating oil is formed on the outer peripheral portion. It is comprised by the member (89).

  In the fourth invention, by inserting the rod-shaped member (89) having the spiral groove (89e) formed in the groove communication passage (85), the outer periphery of the rod-shaped member (89) in the groove communication passage (85). A spiral narrow passage is formed on the side. As a result, the flow rate of the lubricating oil flowing into the groove communication passage (85) is restricted in the spiral narrow passage formed on the outer peripheral side of the rod-like member (89).

  In a fifth aspect based on the fourth aspect, the bar-shaped member (89) is provided at a plurality of locations of the groove communication path (85).

  In the fifth aspect of the invention, the bar-like member (89) constituting the throttle portion is provided at a plurality of locations in the groove communication path (85). Here, when only one rod-like member (89) is provided in the groove communication path (85), a certain length of narrow flow path is required to sufficiently limit the flow rate of the lubricating oil, The rod-shaped member (89) must be formed long. However, by providing the rod-shaped members (89) at a plurality of locations in the groove communication passage (85) as described above, even if the length of one rod-shaped member (89) is short, the total length of the narrow passage is become longer.

  A sixth invention includes a bearing (55) provided separately from the compression mechanism (20) and rotatably supporting the drive shaft (60) in the fifth invention, and the bearing (55) The fixed scroll (30) is formed with communication holes (83, 81) that form a part of the groove communication path (85), and the rod-shaped members (83, 81) are formed in the communication holes (83, 81). 89).

  In the sixth invention, the bearing (55) and the fixed scroll (30) are formed with communication holes (83, 81) that form a part of the groove communication path (85), and each communication hole (83 , 81) are provided with rod-like members (89) constituting the throttle part. Therefore, when one rod-shaped member (89) is provided on either the bearing (55) or the fixed scroll (30), a certain length of narrow flow path is required to sufficiently limit the flow rate of the lubricating oil. Therefore, the rod-shaped member (89) and the communication hole provided with the rod-shaped member (89) must be formed long. However, as described above, by forming the communication holes (83, 81) in both the bearing (55) and the fixed scroll (30) and providing the rod-shaped members (89) respectively, one rod-shaped member (89) And even if the length of the communication hole (83, 81) is short, the total length of the narrow passage becomes long.

  According to a seventh invention, in any one of the first to sixth inventions, an electric motor (50) for rotationally driving the drive shaft (60), and between the casing (15) and the electric motor (50). A connecting pipe (84) that is provided and forms a part of the groove communication path (85). The connecting pipe (84) is made of a resin pipe formed of a resin material or an outer peripheral surface thereof covered with the resin material. It is comprised by the made metal piping.

  In the seventh invention, the connecting pipe (84) that forms a part of the groove communication path (85) is provided between the casing (15) and the electric motor (50).

  By the way, when providing a metal pipe on the side of the electric motor (50), it is necessary to separate it from the electric motor (50) by a distance that ensures insulation. Therefore, the diameter of the casing (15) had to be increased by the distance between the electric motor (50) and the pipe.

  On the other hand, in 7th invention, the connection pipe (84) is comprised by the resin piping in which the resin material was formed by the resin material, or the outer peripheral surface was coat | covered with the resin material. Therefore, insulation can be ensured without providing the connecting pipe (84) away from the electric motor (50).

  According to an eighth invention, in any one of the first to seventh inventions, the lubricating oil inlet (88) of the groove communication passage (85) is provided as a lubricating oil of the bearing oil supply passage (70). It is formed above the inflow port (76).

  Part of the lubricating oil supplied from the oil reservoir (18) in the casing (15) to the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) via the oil groove (80) It flows into the compression chamber and is discharged to the outside of the casing (15) together with the compressed refrigerant. For this reason, in the oil sump (18) in the casing (15), the amount of lubricating oil decreases and the oil level decreases. The oil level of the oil reservoir (18) in the casing (15) is greater than the lubricating oil inlet (76) of the bearing oil supply passage (70) and the lubricating oil inlet (88) of the groove communication passage (85). When the pressure drops, the lubricating oil cannot be supplied from the oil reservoir (18) to the bearing of the drive shaft (60) and the oil groove (80).

  If the amount of lubricating oil supplied to the bearing of the drive shaft (60) is insufficient, the bearing may be seized and damaged. On the other hand, if the oil groove (80) is insufficiently lubricated, the frictional force generated on the movable thrust sliding surface (45) of the movable scroll (40) and the fixed thrust sliding surface (35) of the fixed scroll (30) May increase and the power consumption of the motor may increase.

  Here, the insufficient supply amount of the lubricating oil to the bearing of the drive shaft (60) may cause the bearing to be fatally damaged even in a short time, and the compressor may not operate normally. On the other hand, the shortage of lubricating oil supply to the oil groove (80) via the groove communication passage (85) is temporary due to insufficient sealing of the thrust sliding surface (35, 45) for a short time. Will be fatal but not fatal. That is, the shortage of oil supply to the bearing of the drive shaft (60) needs to be taken promptly compared to the shortage of oil supply to the oil groove (80).

  In contrast, in the eighth aspect of the invention, the lubricating oil inlet (88) of the groove communication passage (85) is formed above the lubricating oil inlet (76) of the bearing oil supply passage (70). Yes. Therefore, when the amount of lubricating oil in the oil sump (18) in the casing (15) decreases, the oil level of the oil sump (18) first falls below the inlet (88) of the groove communication passage (85), and the oil groove Lubricant is no longer supplied to (80). As a result, the amount of lubricating oil discharged together with the refrigerant to the outside of the casing (15) is reduced, and the oil level of the oil reservoir (18) in the casing (15) is suppressed from being lowered.

  In the first aspect of the invention, the oil groove (80) is formed on the movable thrust sliding surface (45) of the movable scroll (40) or the fixed thrust sliding surface (35) of the fixed scroll (30). Yes. Further, the bearing oil supply passage (70) for supplying lubricating oil to the bearing of the compression mechanism (20) is not in communication with the oil groove (80). For this reason, even if the movable scroll (40) is inclined during the operation of the compression mechanism (20) and the pressure in the oil groove (80) is rapidly reduced, the pressure in the bearing oil supply passage (70) does not change.

  Here, assuming that the oil groove (80) and the bearing oil supply passage (70) are in communication with each other, when the pressure in the oil groove (80) decreases rapidly, the oil supply passage for the bearing (70) The pressure will also decrease. If the pressure in the bearing oil supply passage (70) decreases, the lubricating oil flows backward from the bearing of the compression mechanism (20) to the bearing oil supply passage (70), and there is a risk that the lubricating oil for lubricating the bearing will be insufficient. is there.

  In contrast, in the first aspect of the invention, the bearing oil supply passage (70) is not in communication with the oil groove (80), and even if the pressure in the oil groove (80) is suddenly reduced, the bearing oil supply passage is provided. The pressure of (70) does not change. Therefore, according to the first aspect of the invention, even when the movable scroll (40) is inclined and the pressure in the oil groove (80) is suddenly reduced, the bearing of the compression mechanism (20) to the bearing oil supply passage (70). The lubricating oil does not flow backward, and the lubricating oil can be reliably supplied to the bearing of the compression mechanism (20) through the bearing oil supply passage (70). As a result, the bearing of the compression mechanism (20) can always be lubricated reliably, and troubles such as seizure can be prevented and the reliability of the scroll compressor (10) can be improved.

  In the second aspect of the invention, the lubricating oil discharged from the oil supply pump (75) driven by the drive shaft (60) passes through the bearing oil supply passage (70) that does not communicate with the oil groove (80), and then is compressed. Supplied to the bearing of (20). Therefore, even when the movable scroll (40) is tilted during operation of the compression mechanism (20) and the pressure in the oil groove (80) is suddenly reduced, the lubricating oil is stably supplied to the bearing of the compression mechanism (20). can do. Therefore, according to the present invention, the lubricating oil can be reliably supplied to the bearing of the compression mechanism (20) regardless of the pressure in the oil groove (80), and the reliability of the scroll compressor (10) can be improved. .

  In the third aspect of the invention, the throttle portion is provided in the groove communication path (85). Therefore, even when the movable scroll (40) is tilted and the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) is increased, the flow rate of the lubricating oil in the groove communication passage (85) Is limited by the aperture.

  Here, if the movable scroll (40) tilts during operation of the compression mechanism (20), the lubricating oil passes through the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). The pressure loss is reduced, and the pressure acting on the thrust sliding surface (35, 45) may increase to the same level as the lubricating oil pressure in the oil groove (80). In this case, the force for pulling the movable scroll (40) away from the fixed scroll (30) increases, and the airtightness of the compression chamber (521) may be reduced.

  On the other hand, in the third aspect of the invention, the throttle portion is provided in the groove communication passage (85), and the oil groove (80) extends from the groove communication passage (85) even when the movable scroll (40) is inclined. The flow rate of the lubricating oil flowing into the water is kept low, and the pressure in the oil groove (80) is kept low. Therefore, even when the movable scroll (40) is tilted during the operation of the compression mechanism (20), the pressure acting on the thrust sliding surfaces (35, 45) is kept low, and the movable scroll (40) is fixed to the fixed scroll (30 The power to pull away from) will not be excessive. On the other hand, a pressing force for pressing the movable scroll (40) against the fixed scroll (30) acts on the movable scroll (40). For this reason, the movable scroll (40) tilted during the operation of the compression mechanism (20) receives this pressing force and quickly returns to its original posture. Therefore, according to the present invention, the movable scroll (40) inclined during the operation of the compression mechanism (20) can be quickly returned to the original posture, and the airtightness of the compression chamber (521) is ensured and scroll compression is ensured. The performance degradation of the machine (10) can be suppressed.

  In the fourth aspect of the present invention, the lubricating oil in the groove communication path (85) can be obtained simply by inserting the rod-shaped member (89) having the spiral groove (89e) formed in the outer peripheral portion into the groove communication path (85). The throttle part for limiting the flow rate can be easily formed. Moreover, the passage sectional area of the groove communication passage (85) can be easily changed only by changing the sectional shape of the spiral groove (89e) on the outer peripheral portion of the rod-like member (89). That is, by configuring the throttle portion with the rod-shaped member (89), the degree of freedom in design is improved and the design can be easily changed.

  In addition, when the throttle member that restricts the flow rate of the lubricating oil in the groove communication passage (85) is configured by the rod-like member (89) having the spiral groove (89e) formed on the outer peripheral portion as described above, a sufficient throttle effect is achieved. In order to obtain this, it is necessary to lengthen the length of the narrow passage formed by the spiral groove (89e) to some extent. However, if the length of the rod-shaped member (89) is increased to increase the length of the narrow passage, a long space is required to install the rod-shaped member (89), and there is a risk that the installation work may be time-consuming.

  On the other hand, in the fifth invention, since the rod-like member (89) constituting the throttle portion is provided at a plurality of locations in the groove communication passage (85), the length of one rod-like member (89) is short. However, the total length of the narrow passage can be increased. Therefore, the flow rate of the lubricating oil in the groove communication path (85) can be sufficiently limited. In other words, the length of each rod-shaped member (89) can be shortened by providing the rod-shaped member (89) at a plurality of locations in the groove communication path (85). Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

  In the sixth aspect of the invention, the communication holes (83, 81) that form a part of the groove communication path (85) are formed in both the bearing (55) and the fixed scroll (30), and the restricting portions are respectively provided. Since the rod-shaped member (89) is provided, the total length of the narrow passage can be increased even if the length of one rod-shaped member (89) and the communication hole (83, 81) is short. Therefore, the flow rate of the lubricating oil in the groove communication path (85) can be sufficiently limited. In other words, the communication holes (83, 81) are formed in both the bearing (55) and the fixed scroll (30), and the rod-shaped members (89) are provided in each, thereby reducing the length of each rod-shaped member (89). Can be shortened. Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

  In the seventh invention, the connecting pipe (84) provided between the casing (15) and the electric motor (50) and forming a part of the groove communication path (85) is formed of a resin material. The resin pipe or the outer peripheral surface is constituted by a metal pipe covered with a resin material. Thereby, since insulation can be secured without providing the connecting pipe (84) away from the electric motor (50), the diameter of the casing (15) can be reduced. That is, it is possible to reduce the size of the scroll compressor.

  In the eighth aspect of the invention, the lubricating oil inlet (88) of the groove communication passage (85) is provided above the lubricating oil inlet (76) of the bearing oil supply passage (70). For this reason, even if the oil level of the oil sump (18) in the casing (15) decreases, the lubricating oil is first not supplied to the oil groove (80), so that it is discharged together with the refrigerant to the outside of the casing (15). The amount of lubricating oil is reduced. As a result, a decrease in the oil level of the oil sump (18) in the casing (15) is suppressed. Therefore, according to the eighth invention, even if the oil level of the oil sump (18) in the casing (15) starts to decrease, the oil level is suppressed by stopping the oil supply to the oil groove (80). be able to. As a result, the oil level in the oil reservoir (18) in the casing (15) is prevented from lowering to a position below the lubricating oil inlet (76) in the bearing oil supply passage (70). It is possible to ensure oil supply to the bearing of the drive shaft (60). That is, giving priority to oil supply to the bearing of the drive shaft (60) over oil supply to the oil groove (80) can prevent fatal damage to the bearing due to seizure of the bearing of the drive shaft (60).

It is a longitudinal cross-sectional view which shows the whole structure of the scroll compressor of Embodiment 1. It is a longitudinal cross-sectional view which shows the structure of the principal part of the scroll compressor of Embodiment 1. It is a cross-sectional view which shows the structure of the compression mechanism of the scroll compressor of Embodiment 1. It is a longitudinal cross-sectional view which shows the structure of the principal part of the scroll compressor of Embodiment 2. It is a longitudinal cross-sectional view which shows the whole structure of the scroll compressor of Embodiment 3. It is a longitudinal cross-sectional view which shows the structure of the 1st and 2nd connection channel | path of the scroll compressor of Embodiment 3. It is a longitudinal cross-sectional view which shows the structure of the 3rd connection channel | path of the scroll compressor of Embodiment 3. It is a longitudinal cross-sectional view which shows the structure of the connecting pipe of the scroll compressor of Embodiment 3. It is a longitudinal cross-sectional view which shows the structure of the principal part of the conventional scroll compressor.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 of the Invention
A first embodiment of the present invention will be described. The scroll compressor (10) of this embodiment is a hermetic compressor. The scroll compressor (10) is connected to a refrigerant circuit that performs a refrigeration cycle, and sucks and compresses refrigerant in the refrigerant circuit.

<Overall configuration of scroll compressor>
As shown in FIG. 1, in the scroll compressor (10), a compression mechanism (20), an electric motor (50), a lower bearing member (55), and a drive shaft (60) are provided in the internal space of the casing (15). And is housed. The casing (15) is a sealed container formed in a vertically long cylindrical shape. In the internal space of the casing (15), a compression mechanism (20), an electric motor (50), and a lower bearing member (55) are arranged in order from the top to the bottom. Further, the drive shaft (60) is arranged in such a posture that its axial direction is along the height direction of the casing (15). The detailed structure of the compression mechanism (20) will be described later.

  A suction pipe (16) and a discharge pipe (17) are attached to the casing (15). The suction pipe (16) and the discharge pipe (17) both penetrate the casing (15). The suction pipe (16) is connected to the compression mechanism (20). The discharge pipe (17) opens in a portion between the electric motor (50) and the compression mechanism (20) in the internal space of the casing (15).

  The lower bearing member (55) includes a central cylindrical portion (56) and an arm portion (57). Although only one is shown in FIG. 1, the lower bearing member (55) is provided with three arms (57). The central cylindrical portion (56) is formed in a substantially cylindrical shape. Each arm portion (57) extends outward from the outer peripheral surface of the central cylindrical portion (56). In the lower bearing member (55), the three arm portions (57) are arranged at substantially equal angular intervals. The protruding end portion of each arm portion (57) is fixed to the casing (15). Near the upper end of the central cylindrical portion (56), a bearing metal (58) is inserted. A sub journal portion (67) of a drive shaft (60), which will be described later, is inserted through the bearing metal (58). The central cylindrical portion (56) constitutes a journal bearing that supports the sub journal portion (67).

  The electric motor (50) includes a stator (51) and a rotor (52). The stator (51) is fixed to the casing (15). The rotor (52) is arranged coaxially with the stator (51). A main shaft portion (61) of a drive shaft (60), which will be described later, is inserted through the rotor (52).

  The drive shaft (60) is formed with a main shaft portion (61), a balance weight portion (62), and an eccentric portion (63). The balance weight part (62) is disposed in the middle of the main shaft part (61) in the axial direction. The main shaft portion (61) has a lower portion than the balance weight portion (62) passing through the rotor (52) of the electric motor (50). Further, in the main shaft portion (61), the portion above the balance weight portion (62) constitutes the main journal portion (64), and the sub journal portion (67) below the portion penetrating the rotor (52). ) Is formed. The main journal portion (64) is inserted through a bearing metal (28) provided in the central bulge portion (27) of the housing (25). The sub-journal part (67) is inserted through a bearing metal (58) provided in the central cylindrical part (56) of the lower bearing member (55).

  The eccentric part (63) is formed in a cylindrical shape having a smaller diameter than the main journal part (64), and projects from the upper end surface of the main journal part (64). The shaft center of the eccentric portion (63) is parallel to the shaft center of the main journal portion (64) (that is, the shaft center of the main shaft portion (61)) and is eccentric to the shaft center of the main journal portion (64). Yes. The eccentric part (63) is inserted into a bearing metal (44) provided in the cylindrical part (43) of the movable scroll (40).

  An oil supply passage (77) is formed in the drive shaft (60). The oil supply passage (77) includes one main passage (74) and three branch passages (71 to 73). The main passage (74) extends along the axis of the drive shaft (60), and one end thereof opens to the lower end of the main shaft portion (61) and the other end opens to the upper end surface of the eccentric portion (63). ing. The first branch passage (71) is formed in the eccentric part (63). The first branch passage (71) extends from the main passage (74) to the outer side in the radial direction of the eccentric portion (63), and is open to the outer peripheral surface of the eccentric portion (63). The second branch passage (72) is formed in the main journal portion (64). The second branch passage (72) extends from the main passage (74) to the outer side in the radial direction of the main journal portion (64), and opens on the outer peripheral surface of the main journal portion (64). The third branch passage (73) is formed in the secondary journal section (67). The third branch passage (73) extends from the main passage (74) to the outer side in the radial direction of the sub journal portion (67), and is open to the outer peripheral surface of the sub journal portion (67).

  An oil supply pump (75) is attached to the lower end of the drive shaft (60). The oil supply pump (75) is a trochoid pump driven by the drive shaft (60). The oil supply pump (75) is disposed near the start end of the main passage (74) of the oil supply passage (77). In addition, the oil supply pump (75) has a suction port (76) that opens downward at the lower end and sucks refrigeration oil, which is lubricating oil. The oil supply pump (75) is not limited to the trochoid pump, and may be a positive displacement pump driven by the drive shaft (60). Therefore, the oil supply pump (75) may be a gear pump, for example. The oil supply pump (75) and the oil supply passage (77) constitute a bearing oil supply passage (70) for supplying refrigeration oil to a journal bearing of the compression mechanism (20) described later. In addition, the suction port (76) of the oil supply pump (75) constitutes a refrigerating machine oil inlet of the bearing oil supply passage (70).

  Refrigerating machine oil, which is lubricating oil, is stored at the bottom of the casing (15). That is, an oil sump (18) is formed at the bottom of the casing (15). When the drive shaft (60) rotates, the oil supply pump (75) sucks and discharges refrigeration oil from the oil reservoir (18), and the refrigeration oil discharged from the oil supply pump (75) flows through the main passage (74). The refrigeration oil flowing through the main passage (74) is supplied to the lower bearing member (55), the compression mechanism (20), and the sliding portion of the drive shaft (60). Since the oil supply pump (75) is a positive displacement pump, the flow rate of the refrigeration oil in the main passage (74) is proportional to the rotational speed of the drive shaft (60).

<Configuration of compression mechanism>
As shown also in FIG. 2, the compression mechanism (20) includes a housing (25), a fixed scroll (30), and a movable scroll (40). The compression mechanism (20) is provided with an Oldham coupling (24) for restricting the rotation of the movable scroll (40).

  The housing (25) is formed in a thick disk shape, and its outer peripheral edge is fixed to the casing (15). A central concave portion (26) and an annular convex portion (29) are formed in the central portion of the housing (25). The central recess (26) is a cylindrical recess that opens on the upper surface of the housing (25). The annular convex portion (29) is formed along the outer periphery of the central concave portion (26) and protrudes from the upper surface of the housing (25). The protruding end surface of the annular convex portion (29) is a flat surface. A ring-shaped concave groove is formed along the circumferential direction of the projecting end surface of the annular convex portion (29), and a seal ring (29a) is fitted into the concave groove.

  A central bulge portion (27) is formed in the housing (25). The central bulging portion (27) is located below the central concave portion (26) and bulges downward. A through-hole penetrating the central bulge portion (27) vertically is formed in the central bulge portion (27), and a bearing metal (28) is inserted into the through-hole. The main journal portion (64) of the drive shaft (60) is inserted through the bearing metal (28) of the central bulge portion (27). The central bulge portion (27) constitutes a journal bearing that supports the main journal portion (64).

  A fixed scroll (30) and a movable scroll (40) are placed on the housing (25). The fixed scroll (30) is fixed to the housing (25) with bolts or the like. On the other hand, the movable scroll (40) is engaged with the housing (25) via the Oldham coupling (24), and is movable relative to the housing (25). The movable scroll (40) engages with the drive shaft (60) to make a revolving motion.

  The movable scroll (40) is a member in which a movable side end plate portion (41), a movable side wrap (42), and a cylindrical portion (43) are integrally formed. The movable side end plate portion (41) is formed in a disc shape. The movable side wrap (42) is formed in a spiral wall shape, and protrudes from the front surface (upper surface in FIGS. 1 and 2) of the movable side end plate portion (41). The cylindrical portion (43) is formed in a cylindrical shape, and protrudes from the back surface (the lower surface in FIGS. 1 and 2) of the movable side end plate portion (41).

  The back surface of the movable side end plate portion (41) of the movable scroll (40) is in sliding contact with a seal ring (29a) provided on the annular convex portion (29) of the housing (25). On the other hand, the cylindrical portion (43) of the movable scroll (40) is inserted from above into the central recess (26) of the housing (25). A bearing metal (44) is inserted into the cylindrical portion (43). An eccentric portion (63) of the drive shaft (60) described later is inserted into the bearing metal (44) of the cylindrical portion (43) from below. The cylindrical portion (43) constitutes a journal bearing that slides with the eccentric portion (63).

  The fixed scroll (30) is a member in which a fixed side end plate portion (31), a fixed side wrap (32), and an outer peripheral portion (33) are integrally formed. The fixed side end plate portion (31) is formed in a disc shape. The fixed side wrap (32) is formed in a spiral wall shape, and protrudes from the front surface (the lower surface in FIGS. 1 and 2) of the fixed side end plate portion (31). The outer peripheral portion (33) is formed in a thick ring shape extending downward from the outer peripheral portion (33) of the fixed-side end plate portion (31) and surrounds the fixed-side wrap (32).

  A discharge port (22) is formed in the fixed side end plate portion (31). The discharge port (22) is a through hole formed in the vicinity of the center of the fixed-side end plate portion (31), and passes through the fixed-side end plate portion (31) in the thickness direction. A suction pipe (16) is inserted in the vicinity of the outer periphery of the fixed-side end plate part (31).

  A discharge gas passage (23) is formed in the compression mechanism (20). The start end of the discharge gas passage (23) communicates with the discharge port (22). Although not shown, the discharge gas passage (23) is formed from the fixed scroll (30) to the housing (25), and the other end opens to the lower surface of the housing (25).

  In the compression mechanism (20), the fixed scroll (30) and the movable scroll (40) have the front surface of the fixed side end plate portion (31) and the front surface of the movable side end plate portion (41) facing each other, and the fixed side wrap (32) The movable wraps (42) are arranged so as to mesh with each other. In the compression mechanism (20), the fixed wrap (32) and the movable wrap (42) mesh with each other to form a plurality of compression chambers (21).

  In the compression mechanism (20), the movable side end plate portion (41) of the movable scroll (40) and the outer peripheral portion (33) of the fixed scroll (30) are in sliding contact with each other. Specifically, in the movable side end plate portion (41), a portion of the front surface (upper surface in FIGS. 1 and 2) on the outer peripheral side of the movable side wrap (42) is in sliding contact with the fixed scroll (30). Thrust sliding surface (45). On the other hand, the outer peripheral portion (33) of the fixed scroll (30) has its protruding end surface (the lower surface in FIGS. 1 and 2) in sliding contact with the movable thrust sliding surface (45) of the movable scroll (40). In the outer peripheral portion (33), a portion of the protruding end surface that is in sliding contact with the movable side thrust sliding surface (45) is a fixed side thrust sliding surface (35).

  As shown in FIGS. 2 and 3, an oil groove (80) and a connection passage (86) are formed in the outer peripheral portion (33) of the fixed scroll (30). The oil groove (80) is a concave groove formed in the fixed-side thrust sliding surface (35) of the outer peripheral portion (33), and is formed in a ring shape surrounding the periphery of the fixed-side wrap (32). One end of the connection passage (86) communicates with the oil groove (80). The connecting passage (86) is a passage extending from one end thereof toward the outer periphery of the outer peripheral portion (33). A capillary tube (87), which will be described later, is connected to the vicinity of the other end of the connection passage (86). The connection passage (86) and the capillary tube (87) constitute a groove communication passage (85).

  The capillary tube (87) is a thin copper tube having an inner diameter of about 0.5 to 1.0 mm, and constitutes a throttle portion. The capillary tube (87) is provided along the inner surface of the casing (15). Specifically, the upper end portion of the capillary tube (87) is inserted into a through hole formed in the housing (25) and is inserted into the outer peripheral portion (33) of the fixed scroll (30) to be connected to the connection passage (86). Communicate. The capillary tube (87) is inserted through a core cut portion formed in the stator (51) of the electric motor (50) and extends to the oil reservoir (18). That is, the lower end of the capillary tube (87) is immersed in the refrigerating machine oil stored at the bottom of the casing (15).

  The lower end opening (88) of the capillary tube (87) constitutes an inflow port through which the refrigeration oil flows into the groove communication passage (85). The lower end opening (88) of the capillary tube (87) is formed above the suction port (76) of the oil supply pump (75). In the present embodiment, the lower end opening (88) of the capillary tube (87) is formed at a height position about 10 mm above the suction port (76) of the oil supply pump (75). That is, the inlet of the groove communication passage (85) is formed above the inlet of the refrigerating machine oil in the bearing oil supply passage (70).

  In the present embodiment, the groove communication passage (85) constituted by the connection passage (86) and the capillary tube (87) has the oil groove (80) only in the oil reservoir (18) in the casing (15). Connected. Therefore, in this embodiment, the oil supply passage (77) formed in the drive shaft (60) is not in communication with the oil groove (80) formed in the fixed scroll (30). That is, the bearing oil supply passage (70) is not in communication with the oil groove (80).

-Driving action-
The operation of the scroll compressor (10) will be described.

<Operation to compress refrigerant>
In the scroll compressor (10), when the electric motor (50) is energized, the movable scroll (40) is driven by the drive shaft (60). The orbiting scroll (40) has its rotation motion restricted by the Oldham coupling (24), and does not rotate but only revolves.

  When the orbiting scroll (40) revolves, the low-pressure gas refrigerant that has flowed into the compression mechanism (20) through the suction pipe (16) becomes the outer peripheral side of the fixed side wrap (32) and the movable side wrap (42). It is sucked into the compression chamber (21) from near the end. When the movable scroll (40) is further moved, the compression chamber (21) is closed from the suction pipe (16), and then the compression chamber (21) is separated from the fixed wrap (32) and the movable wrap ( 42) and move toward the inner circumferential edge. In the process, the volume of the compression chamber (21) gradually decreases, and the gas refrigerant in the compression chamber (21) is compressed.

  As the volume of the compression chamber (21) gradually decreases as the movable scroll (40) moves, the compression chamber (21) eventually communicates with the discharge port (22). Then, the refrigerant compressed in the compression chamber (21) (that is, high-pressure gas refrigerant) flows into the discharge gas passage (23) through the discharge port (22), and then the internal space of the casing (15). Is discharged. In the internal space of the casing (15), the high-pressure gas refrigerant discharged from the compression mechanism (20) is once guided below the stator (51) of the electric motor (50), and then the rotor (52) And flows through the gap between the stator (51) and the like, and flows out of the casing (15) through the discharge pipe (17).

  The high pressure gas refrigerant discharged from the compression mechanism (20) circulates in the inner space of the casing (15) below the housing (25), and the pressure is substantially equal to the pressure of the high pressure gas refrigerant. Are equal. Therefore, the pressure of the refrigerating machine oil stored in the oil sump (18) in the casing (15) is also substantially equal to the pressure of the high-pressure gas refrigerant.

  On the other hand, the portion of the internal space of the casing (15) above the housing (25) communicates with the suction pipe (16) (not shown), and the low pressure gas whose pressure is sucked into the compression mechanism (20) It is about the same as the pressure of the refrigerant. Therefore, in the compression mechanism (20), the pressure in the space near the outer periphery of the movable side end plate portion (41) of the movable scroll (40) is approximately the same as the pressure of the low-pressure gas refrigerant.

<Oil supply operation for compression mechanism>
During operation of the scroll compressor (10), the oil supply pump (75) is driven by the rotating drive shaft (60), and the refrigerating machine oil stored at the bottom of the casing (15) is the main passage of the oil supply passage (77). Sucked up to (74). A part of the refrigerating machine oil flowing through the main passage (74) flows into the branch passages (71 to 73), and the rest flows out from the upper end of the main passage (74).

  The refrigerating machine oil flowing into the first branch passage (71) is supplied to the gap between the eccentric portion (63) and the bearing metal (44), and is used for lubrication and cooling of the eccentric portion (63) and the bearing metal (44). . The refrigeration oil that flows into the second branch passage (72) is supplied to the gap between the main journal (64) and the bearing metal (28), and is used for lubrication and cooling of the main journal (64) and the bearing metal (28). Is done. The refrigeration oil that has flowed into the third branch passage (73) is supplied to the gap between the sub journal (67) and the bearing metal (58), and is used for lubrication and cooling of the sub journal (67) and the bearing metal (58). Is done. In the compression mechanism (20), the refrigeration oil is also supplied to the sliding portion of the movable scroll (40) and the Oldham coupling (24) and the sliding portion of the movable scroll (40) and the fixed scroll (30).

<Operation of pressing the movable scroll>
The compression mechanism (20) of the present embodiment is configured to press the movable scroll (40) against the fixed scroll (30) using the refrigerating machine oil supplied from the oil sump (18) in the casing (15). ing.

  Specifically, in the compression mechanism (20), the back surface of the movable side end plate portion (41) is in sliding contact with the seal ring (29a). Refrigerating machine oil flowing out from the end of the main passage (74) of the oil supply passage (77) exists in the central recess (26) located inside the seal ring (29a). The pressure of the refrigerating machine oil is approximately the same as the pressure of the refrigerating machine oil in the oil reservoir (18). The movable scroll (40) flows out of the main passage (74) into the portion of the back surface of the movable side end plate portion (41) located inside the seal ring (29a) and the surface of the cylindrical portion (43). The pressure of the refrigerating machine oil acted. Therefore, a pressing force that is a force in the direction toward the fixed scroll (30) (upward force in the present embodiment) acts on the movable scroll (40). As a result, the movable scroll (40) is pressed against the fixed scroll (30) even during the operation of the compression mechanism (20), and the airtightness of the compression chamber (21) is ensured.

  However, the pressing force acting on the movable scroll (40) may become too strong. If the pressing force becomes too strong, the frictional force acting between the movable scroll (40) and the fixed scroll (30) increases, and the power consumption of the electric motor (50) increases.

  In contrast, in the scroll compressor (10) of the present embodiment, the oil groove (80) communicates with the oil sump (18) in the casing (15) via the groove communication path (85), The groove (80) is filled with high-pressure refrigeration oil. On the other hand, the pressure in the compression chamber (21) adjacent to the oil groove (80) (that is, the compression chamber (21) formed near the outermost periphery of the wrap (32, 42)) is sucked into the compression chamber (21). The pressure of the low-pressure refrigerant is lower than the pressure of the refrigeration oil in the oil groove (80). Therefore, the refrigerating machine oil in the oil groove (80) gradually flows out into the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35), and these thrust sliding surfaces (35, 45 ) Used for lubrication.

  Thus, in the scroll compressor (10) of the present embodiment, the refrigerating machine oil is reliably supplied to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). For this reason, even when the movable scroll (40) is strongly pressed against the fixed scroll (30), the frictional force generated on the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) becomes excessive. There is nothing.

<Operation when the movable scroll is tilted>
In the movable scroll (40) of the scroll compressor (10), the internal pressure of the compression chamber (21) acts on the movable side wrap (42) protruding from the front surface of the movable side end plate (41), and the movable end plate (41) The load from the eccentric part (63) acts on the cylindrical part (43) projecting from the back surface of. The line of action of the gas pressure acting on the movable side wrap (42) and the load acting on the cylindrical portion (43) are perpendicular to the axial direction of the movable scroll (40) and do not intersect each other. For this reason, during the operation of the compression mechanism (20), a moment is generated to tilt the movable scroll (40). If the pressing force acting on the movable scroll (40) is sufficiently large, the movable scroll (40) will not tilt even if such a moment is applied.

  However, in an operation state in which sufficient pressing force cannot be obtained, the movable scroll (40) may tilt, and the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) may increase. For example, an operating state where the pressure difference between the low pressure gas refrigerant sucked into the compression mechanism (20) and the high pressure gas refrigerant discharged from the compression mechanism (20) is small, or the rotational speed of the drive shaft (60) becomes very low ( In an operating state (for example, about 10 to 20 revolutions per second), there is a possibility that sufficient pressing force cannot be obtained.

  As described above, in the compression mechanism (20), the pressure in the space near the outer periphery of the movable side end plate portion (41) is approximately the same as the pressure of the low-pressure gas refrigerant sucked into the compression mechanism (20). On the other hand, if the movable scroll (40) tilts and the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) increases, the refrigeration oil in the gap between these thrust sliding surfaces (35, 45). The distribution resistance of is reduced. For this reason, when the movable scroll (40) is inclined, a large amount of refrigerating machine oil may be ejected from the oil groove (80) to the space near the outer periphery of the movable side end plate (41).

  In addition, when the movable scroll (40) is tilted, the pressure loss when the refrigeration oil passes through the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) decreases, and the thrust sliding surface The pressure acting on (35,45) may rise to the same level as the pressure of the refrigeration oil in the oil groove (80). In this case, the force for pulling the movable scroll (40) away from the fixed scroll (30) increases, and the airtightness of the compression chamber (521) may be reduced.

  In contrast, in the scroll compressor (10) of the present embodiment, the capillary tube (87) is provided in the groove communication path (85). Even when the movable scroll (40) is inclined to increase the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35), the flow rate of the refrigerating machine oil in the groove communication passage (85) is Limited by the capillary tube (87).

  Thus, in the compression mechanism (20) of the present embodiment, the flow rate of the refrigerating machine oil flowing into the oil groove (80) from the groove communication path (85) can be kept low even when the movable scroll (40) is tilted. The pressure in the oil groove (80) can be kept low. Therefore, even when the movable scroll (40) is tilted during the operation of the compression mechanism (20), the pressure acting on the thrust sliding surfaces (35, 45) is kept low, and the movable scroll (40) is fixed to the fixed scroll (30 The power to pull away from) will not be excessive. On the other hand, a pressing force for pressing the movable scroll (40) against the fixed scroll (30) acts on the movable scroll (40). For this reason, the movable scroll (40) tilted during the operation of the compression mechanism (20) receives this pressing force and quickly returns to its original posture.

  Here, when the pressure loss from the one end of the groove communication passage (85) to the other end is too low, the movable scroll (40) is inclined and the pressure in the oil groove (80) is reduced. The flow rate of the refrigerating machine oil in the communication passage (85) increases rapidly, and a large amount of refrigerating machine oil is ejected from the end of the groove communication path (85). On the other hand, if the pressure loss between the refrigeration oil from one end of the groove communication passage (85) to the other end is too high, the pressure in the oil groove (80) will be sufficiently high after the tilt of the movable scroll (40) is eliminated. It takes a long time to rise, and there is a risk that the amount of refrigerating machine oil supplied to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) will be insufficient.

  Therefore, in the present embodiment, the groove communication passage (85) is constituted by the connection passage (86) and the capillary tube (87). In this embodiment, the inner diameter and length of the capillary tube (87) are set so that the pressure loss from the one end of the groove communication passage (85) to the other end of the refrigerating machine oil becomes an appropriate value. The

<Operation to suppress oil level drop in oil reservoir>
As described above, in the scroll compressor (10) of the present embodiment, the refrigerating machine oil in the oil groove (80) slightly enters the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). It flows out one by one and is used to lubricate these thrust sliding surfaces (35, 45). Part of the refrigerating machine oil used for lubrication flows into the compression chamber (21) adjacent to the oil groove (80), is discharged into the internal space of the casing (15) together with the gas refrigerant, and is scattered into the internal space. . The refrigerating machine oil scattered in the internal space of the casing (15) is once led downward from the stator (51) of the electric motor (50) together with the gas refrigerant, and partly falls and accumulates in the oil sump (18). The remainder flows together with the gas refrigerant through the gap between the rotor (52) and the stator (51), etc., and is discharged to the outside of the casing (15) through the discharge pipe (17).

  The refrigerating machine oil discharged to the outside of the casing (15) together with the gas refrigerant as described above circulates in the refrigerant circuit to which the scroll compressor (10) is connected together with the refrigerant, and is sucked into the scroll compressor (10) again. The The refrigerating machine oil drawn into the scroll compressor (10) is discharged into the internal space of the casing (15) together with the compressed gas refrigerant, and a part thereof is returned to the oil reservoir (18) in the casing (15).

  By the way, depending on the operation state, the refrigeration oil may not be easily returned into the casing (15) of the scroll compressor (10). For example, if the temperature of the evaporator is low, the viscosity of the refrigerating machine oil increases, and the refrigerating machine oil is likely to accumulate in the evaporator, making it difficult to return to the scroll compressor (10). If such an operating state continues, the amount of refrigerating machine oil discharged together with the gas refrigerant from the casing (15) becomes larger than the amount of refrigerating machine oil returned to the casing (15), and the refrigerating machine oil in the oil reservoir (18) The amount decreases and the oil level decreases. And the oil level of the oil sump (18) in the casing (15) is the suction port (76) of the oil supply pump (75) (refrigerating machine oil inlet of the bearing oil supply passage (70)) and the capillary tube (87). If it drops below the lower end opening (88) (refrigerant oil inlet of the groove communication passage (85)), the oil pool (18) freezes into the journal bearing and oil groove (80) of the compression mechanism (20). Machine oil cannot be supplied.

  If the supply amount of refrigeration oil to the journal bearing of the compression mechanism (20) is insufficient, the journal bearing may be damaged by seizure. On the other hand, if the oil groove (80) is insufficiently lubricated, the frictional force generated on the movable thrust sliding surface (45) of the movable scroll (40) and the fixed thrust sliding surface (35) of the fixed scroll (30) May increase and the power consumption of the motor may increase.

  Here, the shortage of the supply amount of the refrigerating machine oil to the bearing of the drive shaft (60) may fatally damage the journal bearing even in a short time, and the compressor may not operate normally. On the other hand, insufficient supply of refrigerating machine oil to the oil groove (80) may cause fatal damage, although performance will be temporarily reduced due to insufficient sealing of the thrust sliding surface (35, 45) for a short time. There is no. That is, the shortage of oil supply to the journal bearing of the compression mechanism (20) needs to be taken promptly compared to the shortage of oil supply to the oil groove (80).

  In contrast, in the scroll compressor (10) of the present embodiment, the lower end opening (88) of the capillary tube (87), which is the inlet of the refrigeration oil in the groove communication passage (85), is the bearing oil supply passage (70). It is provided above the suction port (76) of the oil supply pump (75) that is the inlet of the refrigerating machine oil. As a result, when the amount of refrigerating machine oil in the oil sump (18) in the casing (15) decreases, the oil level of the oil sump (18) first falls below the lower end opening (88) of the capillary tube (87), and the oil groove ( Refrigerating machine oil will not be supplied to 80). Thus, even if the oil level of the oil sump (18) in the casing (15) decreases, first, the refrigerating machine oil is not supplied to the oil groove (80), so that the refrigerant and the outside of the casing (15) are removed. The amount of refrigerating machine oil discharged is reduced. As a result, the amount of refrigerating machine oil discharged to the outside of the casing (15) exceeds the amount of refrigerating machine oil returned to the casing (15), and the oil level of the oil sump (18) in the casing (15) is suppressed. Is done. As a result, the oil level of the oil reservoir (18) in the casing (15) can be prevented from lowering to a position below the suction port (76) of the bearing oil supply passage (70). It is possible to secure oil supply to the journal bearing of the compression mechanism (20).

-Effect of Embodiment 1-
In this embodiment, the oil groove (80) is formed in the fixed-side thrust sliding surface (35) of the fixed scroll (30). Further, the bearing oil supply passage (70) for supplying the refrigeration oil to the journal bearing of the compression mechanism (20) is not in communication with the oil groove (80). For this reason, even if the movable scroll (40) is inclined during the operation of the compression mechanism (20) and the pressure in the oil groove (80) is rapidly reduced, the pressure in the bearing oil supply passage (70) does not change.

  Here, assuming that the oil groove (80) and the bearing oil supply passage (70) are in communication with each other, when the pressure in the oil groove (80) decreases rapidly, the oil supply passage for the bearing (70) The pressure will also decrease. When the pressure in the bearing oil supply passage (70) decreases, the refrigerating machine oil flows backward from the journal bearing of the compression mechanism (20) to the bearing oil supply passage (70), and the refrigerating machine oil for lubricating the journal bearing is insufficient. There is a fear.

  On the other hand, in the present embodiment, the bearing oil supply passage (70) is not in communication with the oil groove (80), and even if the pressure in the oil groove (80) rapidly decreases, the bearing oil supply passage (70 ) Pressure does not change. Therefore, according to the present embodiment, even when the movable scroll (40) is inclined and the pressure in the oil groove (80) is suddenly reduced, the freezing from the journal bearing of the compression mechanism (20) to the bearing oil supply passage (70) is performed. The machine oil does not flow backward, and the refrigeration oil can be reliably supplied to the journal bearing of the compression mechanism (20) through the bearing oil supply passage (70). As a result, the journal bearing of the compression mechanism (20) can always be reliably lubricated, and troubles such as seizure can be prevented and the reliability of the scroll compressor (10) can be improved.

  In the present embodiment, the refrigeration oil discharged from the oil pump (75) driven by the drive shaft (60) is compressed through the bearing oil passage (70) that does not communicate with the oil groove (80). Supplied to the journal bearing of the mechanism (20). Therefore, refrigeration oil is stably supplied to the bearing of the compression mechanism (20) even when the movable scroll (40) is tilted during operation of the compression mechanism (20) and the pressure in the oil groove (80) is suddenly reduced. can do. Therefore, according to this embodiment, refrigeration oil can be reliably supplied to the journal bearing of the compression mechanism (20) regardless of the pressure in the oil groove (80), and troubles such as seizure of the journal bearing can be avoided reliably.

  As described above, when the pressure loss from the one end of the groove communication passage (85) to the other end of the refrigerator oil is too low, the movable scroll (40) is inclined and the movable thrust sliding surface (45) When the clearance of the fixed-side thrust sliding surface (35) is increased, a large amount of refrigeration oil is ejected from the end of the groove communication passage (85). Also, if the pressure loss between the refrigeration oil and one end of the groove communication passage (85) is too high, the pressure in the oil groove (80) is sufficient after the tilt of the movable scroll (40) is eliminated. It takes a long time to rise, and the supply amount of the refrigerating machine oil to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) may be insufficient.

  On the other hand, in this embodiment, a part of the groove communication path (85) is constituted by the capillary tube (87), and the pressure loss between the refrigerating machine oil from one end to the other end of the groove communication path (85). Is set to an appropriate value. For this reason, even when the movable scroll (40) is inclined, it is possible to prevent the flow rate of the refrigerating machine oil in the groove communication path (85) from becoming excessive. As a result, even when the movable scroll (40) is tilted, the pressure in the oil groove (80) is kept low by restricting the flow rate of the refrigerating machine oil flowing into the oil groove (80) from the groove communication path (85). Thus, the tilted movable scroll (40) can be quickly returned to the original posture. When the movable scroll (40) returns to its original position, the pressure in the oil groove (80) is quickly increased to move the movable-side thrust sliding surface (45) and the fixed-side thrust sliding surface (35). The amount of oil supply to the gap can be ensured.

  In the scroll compressor (10) of the present embodiment, the lower end opening (88) of the capillary tube (87), which is the inlet of the refrigeration oil in the groove communication passage (85), is the refrigeration oil in the bearing oil supply passage (70). It is provided above the suction port (76) of the oil supply pump (75) that is the inflow port. Therefore, even if the oil level of the oil sump (18) in the casing (15) decreases, first, the refrigerating machine oil is not supplied to the oil groove (80), so that it is discharged together with the refrigerant to the outside of the casing (15). Refrigerating machine oil amount is reduced. As a result, the amount of refrigerating machine oil discharged to the outside of the casing (15) exceeds the amount of refrigerating machine oil returned to the casing (15), and the oil level of the oil sump (18) in the casing (15) is suppressed. Is done. Therefore, according to the scroll compressor (10) of the present embodiment, the supply of the refrigerating machine oil to the oil groove (80) is stopped even if the oil level of the oil sump (18) in the casing (15) starts to decrease. As a result, the oil level can be prevented from lowering so that the oil level of the oil reservoir (18) does not fall below the inlet (88) of the oil supply pump (75), and the journal of the compression mechanism (20) Oil supply to the bearing can be ensured. That is, fatal damage to the journal bearing can be prevented by giving priority to the oil supply to the journal bearing of the compression mechanism (20) over the oil supply to the oil groove (80).

<< Embodiment 2 of the Invention >>
A second embodiment of the present invention will be described. Here, the difference from the first embodiment will be described for the scroll compressor (10) of the present embodiment.

  As shown in FIG. 4, in the compression mechanism (20) of the present embodiment, an oil groove (80) is formed in the movable scroll (40), not in the fixed scroll (30). Specifically, the oil groove (80) of the present embodiment is formed in the movable side end plate portion (41) of the movable scroll (40). The oil groove (80) is a concave groove formed on the movable side thrust sliding surface (45) of the movable side end plate part (41) and has a ring shape surrounding the movable side wrap (42). Is formed. In the present embodiment, the terminal end of the connection passage (86) is opened in the fixed-side thrust sliding surface (35) of the fixed scroll (30). The end of this connection passage (86) is formed wide so that it can continue to communicate with the oil groove (80) even if the movable scroll (40) moves.

  In the present embodiment, as in the first embodiment, the bearing oil supply passage (70) is disconnected from the oil groove (80), and the oil reservoir (18) in the casing (15) and the oil groove (80) Refrigerating machine oil flows through the groove communication passage (85) only due to the pressure difference, and a part of the groove communication passage (85) is constituted by the capillary tube (87). Therefore, according to the present embodiment, the same effect as in the first embodiment can be obtained.

<< Embodiment 3 of the Invention >>
Embodiment 3 of the present invention will be described. Here, the difference from the first embodiment will be described for the scroll compressor (10) of the present embodiment.

  As shown in FIG. 5, in this embodiment, the configuration of the central cylindrical portion (56) of the lower bearing member (55) is different from that of the first embodiment. Specifically, the central cylindrical portion (56) is formed so as to extend from the upper end to the lower end of the auxiliary shaft portion (67) constituting the lower end portion of the drive shaft (60). Further, a concave portion is formed in the upper end portion of the central cylindrical portion (56), and a rolling bearing (54) is provided in the concave portion. The auxiliary bearing (67) of the drive shaft (60) is inserted through the rolling bearing (54). With this configuration, the central cylindrical portion (56) constitutes a secondary bearing that supports the secondary shaft portion (67).

  In the present embodiment, the groove communication passage (85) includes the first connection passage (81) formed in the fixed scroll (30) and the second connection passage (82) formed in the housing (25). ), A third connecting passage (83) formed in the lower bearing member (55), and a connecting pipe (84) connecting the second connecting passage (82) and the third connecting passage (83). It is constituted by.

  As shown in FIG. 6, the first connection passage (81) is formed in the outer peripheral portion (33) of the fixed scroll (30), and the inner vertical communication hole (up and down) extends vertically at the inner edge of the outer peripheral portion (33). 81a), a lateral communication hole (81b) extending radially in the outer peripheral part (33), and an outer vertical communication hole (81c) extending vertically in the outer edge part of the outer peripheral part (33).

  The inner vertical communication hole (81a) has an upper end opened at the upper surface of the fixed-side end plate portion (31), and a lower end opened at an oil groove (80) formed in the fixed-side thrust sliding surface (35). . A female screw (81d) is formed on the wall portion that forms the upper end of the inner vertical communication hole (81a). The inner vertical communication hole (81a) is provided with a rod-shaped member (89) described later, and the upper end portion of the inner vertical communication hole (81a) is closed by the head (89d) of the rod-shaped member (89).

  The horizontal communication hole (81b) extends radially outward from a position immediately below the female screw (81d) of the inner vertical communication hole (81a), and the outer end opens to the outer peripheral surface of the fixed scroll (30). The opening at the outer end of the horizontal communication hole (81b) is closed by a plug member.

  The outer vertical communication hole (81c) extends downward from a position slightly inward of the outer end of the horizontal communication hole (81b), and its lower end opens at the lower end surface of the fixed scroll (30).

  With such a configuration, the inner vertical communication hole (81a), the horizontal communication hole (81b), and the outer vertical communication hole (81c) communicate with each other in order to connect the oil groove (80) and the lower end surface of the fixed scroll (30). The connecting first connecting passage (81) is formed.

  The second connection passage (82) is formed to extend vertically in the outer peripheral portion of the housing (25). The upper end of the second connection passage (82) opens at the upper end surface of the housing (25), and corresponds to the outer longitudinal communication hole (81c) of the first connection passage (81). ). On the other hand, the lower end of the second connection passage (82) opens to the lower end surface of the housing (25). The second connection passage (82) is formed to have a slightly larger diameter than the outer vertical communication hole (81c) of the first connection passage (81), and the lower end portion is slightly smaller than the other portions. It is formed in a small diameter. An upper end portion (84a) of a connecting pipe (84), which will be described later, and an upper portion (91b) of a connecting pipe (91) are press-fitted into the small diameter portion. With such a configuration, the second connection passage (82) connects the first connection passage (81) and the connecting pipe (84).

  As shown in FIG. 7, the third connecting passage (83) is formed from an inner vertical communication hole (83a) extending vertically in the central cylindrical portion (56) of the lower bearing member (55) and the central cylindrical portion (56). It has a horizontal communication hole (83b) extending in the radial direction over the arm part (57) and an outer vertical communication hole (83c) extending vertically at the outer edge of the arm part (57).

  The inner vertical communication hole (83a) has an upper end connected to the recess and opens below the rolling bearing (54) provided in the recess, while the lower end is the lower end of the central cylindrical portion (56) located in the oil sump (18). Is open. The wall surface forming the upper end portion of the inner vertical communication hole (83a) is formed in the female screw (83d). The inner vertical communication hole (83a) is provided with a rod-shaped member (89) described later, and the upper end portion of the inner vertical communication hole (83a) is closed by the head (89d) of the rod-shaped member (89).

  The horizontal communication hole (83b) extends radially outward from a position immediately below the female screw (83d) that forms the upper end of the inner vertical communication hole (83a), and the outer end is the outer peripheral surface of the arm part (57). Is open. The opening at the outer end of the lateral communication hole (83b) is closed by a plug member. The outer vertical communication hole (83c) has an upper end that opens to the upper end surface of the arm portion (57), while a lower end that opens to the lower end surface of the arm portion (57), and slightly outside the outer end of the horizontal communication hole (83b). It communicates with the lateral communication hole (83b) at a position closer to the inside.

  The lower end (84b) of the connecting pipe (84) is inserted into the upper part of the outer vertical communication hole (83c), while the opening at the lower end is closed by a plug member. Further, the upper end portion of the outer vertical communication hole (83c) is formed in a large diameter portion that is larger in diameter than the middle main body portion. The large-diameter portion has an upper half formed larger in diameter than the lower half, an O-ring (92) is installed in the lower half, and a protrusion (93a) of the pressing member (93) is formed in the upper half. ) Is inserted.

  The pressing member (93) is configured by a metal plate-like piece in which an insertion hole (93b) through which the connecting pipe (84) is inserted and a bolt hole (93c) through which the bolt is inserted are formed. The lower end portion of the peripheral wall portion of the insertion hole (93b) of the pressing member (93) is formed as a protruding portion (93a) protruding downward from the other portions. The holding member (93) is a bolt inserted into the bolt hole (93c) in a state where the protruding portion (93a) is inserted into the large diameter portion of the outer vertical communication hole (83c) so as to hold the O-ring (92). Are fastened to the arm portion (57) of the lower bearing member (55). By inserting the connecting pipe (84) into the O-ring (92) pressed against the outer vertical communication hole (83c) by such a pressing member (93), the internal space of the casing (15) and the outer space The space between the vertical communication hole (83c) is sealed.

  With such a configuration, the inner vertical communication hole (83a), the horizontal communication hole (83b), and the outer vertical communication hole (83c) communicate with each other in order to connect the oil reservoir (18) and the communication pipe (84). 3 connecting passages (83) are formed.

  The connecting pipe (84) is constituted by a resin pipe formed of a resin material. As shown in FIG. 8, the connecting pipe (84) has an upper end portion (84a) formed with a larger diameter than the middle body portion, and a lower end portion (84b) formed with a smaller diameter than the body portion. Yes. A lower portion (91a) of the connecting pipe (91) formed of stainless steel is press-fitted into the upper end portion (84a) formed to have a large diameter.

  The connecting pipe (91) is formed such that the lower part (91a) below the axial center is smaller in diameter than the upper part (91b) above. Specifically, the connecting pipe (91) has an outer diameter of the lower portion (91a) slightly larger than an inner diameter of the upper end (84a) of the connecting pipe (84) and the upper end of the connecting pipe (84). The outer diameter of the upper portion (91b) is substantially equal to the outer diameter of the upper end portion (84a) of the connecting pipe (84), while the outer diameter of the upper portion (91b) is smaller than the outer diameter of the portion (84a).

  As shown in FIG. 6, the upper end (84a) of the connecting pipe (84) into which the lower part (91a) of the connecting pipe (91) is press-fitted is a small-diameter portion at the lower end of the second connecting passage (82). It is press-fitted into. Therefore, the upper end portion (84a) of the connecting pipe (84) and the upper portion (91b) of the connecting pipe (91) abut against the wall surface of the small diameter portion of the lower end portion of the second connecting passage (82), and the casing (15 ) And the second connecting passage (82) are sealed by these two members. Thereby, the 2nd connection channel | path (82) is connected with the inside of a connection pipe | tube (84) via the connection pipe | tube (91), without connecting with the internal space of a casing (15).

  On the other hand, as shown in FIG. 7, the lower end part (84b) of the connecting pipe (84) is inserted into the upper part of the outer vertical communication hole (83c) of the third connecting passage (83). Specifically, the lower end portion (84b) of the communication pipe (84) is inserted into the insertion hole (93b) of the pressing member (93) and the inside of the O-ring (92), and the tip is connected to the third connection passage (83 ) Of the outer vertical communication hole (83c) and the horizontal communication hole (83b). In this way, the connecting pipe (84) is inserted inside the O-ring (92) and inserted into the outer longitudinal communication hole (83c) of the third connecting passage (83), so that the third connecting passage (83 ) Communicates with the interior of the connecting pipe (84) without communicating with the internal space of the casing (15).

  As shown in enlarged views in FIG. 6 and FIG. 7, it is provided in each of the inner vertical communication hole (81 a) of the first connection passage (81) and the inner vertical communication hole (83 a) of the third connection passage (83). The rod-shaped member (89) has a main body part (89a), a small diameter part (89b), a screw part (89c), and a head part (89d) formed continuously from the distal end side to the proximal end side. is doing.

  The main body portion (89a) is formed of a cylindrical rod-like body, and a thin spiral groove (89e) having a width of about 0.5 to 1.0 mm is formed on the outer peripheral portion. By the main body portion (89a) having such a configuration, a spiral narrow passage is formed between each of the inner vertical communication holes (81a, 83a). The small-diameter portion (89b) is formed to have a smaller diameter than the inner vertical communication holes (81a, 83a), and forms an annular passage between the inner wall and the inner vertical communication holes (81a, 83a). In the annular passage, the inner ends of the lateral communication holes (81b, 83b) are opened. The threaded portion (89c) is constituted by a cylindrical rod-like body, and a male thread that is screwed into a female thread (81d, 83d) that forms the upper end of each inner vertical communication hole (81a, 83a) on the outer periphery. Is formed. The head (89d) is formed in a disk shape having a larger diameter than the inner vertical communication holes (81a, 83a).

  By the rod-like member (89) as described above, a spiral narrow passage is formed by the main body portion (89a) in each of the inner vertical communication holes (81a, 83a) provided with the rod-like member (89). As a result, the flow rate of the refrigeration oil flowing into the inner vertical communication holes (81a, 83a) is restricted in the spiral narrow passage formed on the outer peripheral side of the rod-like member (89). That is, the rod-like member (89) constitutes a throttle portion for limiting the flow rate of the refrigeration oil in the groove communication path (85).

  In the present embodiment, the groove communication passage (85) constituted by the first to third connection passages (81 to 83) and the connecting pipe (84) is provided with an oil groove (80) in the casing (15). Only connected to the oil sump (18). Accordingly, also in the present embodiment, as in the first embodiment, the oil supply passage (77) formed in the drive shaft (60) is not in communication with the oil groove (80) formed in the fixed scroll (30). It is in a state. That is, the bearing oil supply passage (70) is disconnected from the oil groove (80), and the refrigerating machine oil is grooved only due to the pressure difference between the oil reservoir (18) in the casing (15) and the oil groove (80). Flows through the communication passage (85).

  Specifically, the refrigerating machine oil in the oil sump (81) is grooved in the order of the third connecting passage (83), the connecting pipe (84), the second connecting passage (82), and the first connecting passage (81). It flows through the communication passage (858) and is supplied to the oil groove (80). As a result, the oil groove (80) is filled with high-pressure refrigerating machine oil, and the refrigerating machine oil in the oil groove (80) is moved between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35 ) Is gradually discharged into the gap, and is used to lubricate these thrust sliding surfaces (35, 45).

  Thus, also in the present embodiment, the refrigerating machine oil is reliably supplied to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). For this reason, even when the movable scroll (40) is strongly pressed against the fixed scroll (30), the frictional force generated on the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) becomes excessive. There is nothing.

  Also in the present embodiment, the groove communication passage (85) is provided with a rod-like member (89) serving as a throttle portion for limiting the flow rate of the refrigerating machine oil. Therefore, also in the present embodiment, even when the movable scroll (40) is inclined to increase the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35), the groove communication path (85) The flow rate of the refrigerating machine oil that has flowed into the pipe is limited in a spiral narrow passage formed on the outer peripheral side of the rod-like member (89).

  Thus, also in this embodiment, even when the movable scroll (40) is tilted, the flow rate of the refrigerating machine oil flowing into the oil groove (80) from the groove communication path (85) is kept low, and the oil groove (80 ) Pressure is kept low. Therefore, even when the movable scroll (40) is tilted during the operation of the compression mechanism (20), the pressure acting on the thrust sliding surfaces (35, 45) is kept low, and the movable scroll (40) is fixed to the fixed scroll (30 The power to pull away from) will not be excessive. On the other hand, a pressing force for pressing the movable scroll (40) against the fixed scroll (30) acts on the movable scroll (40). For this reason, the movable scroll (40) tilted during the operation of the compression mechanism (20) receives this pressing force and quickly returns to its original posture. Therefore, the present embodiment can provide the same effects as those of the first embodiment.

  Further, according to the present embodiment, the freezing in the groove communication path (85) can be achieved by simply inserting the rod-shaped member (89) having the spiral groove (89e) formed in the outer peripheral portion into the groove communication path (85). A throttle portion that limits the flow rate of machine oil can be easily formed. Moreover, the passage sectional area of the groove communication passage (85) can be easily changed only by changing the sectional shape of the spiral groove (89e) on the outer peripheral portion of the rod-like member (89). That is, by configuring the throttle portion with the rod-shaped member (89), the degree of freedom in design is improved and the design can be easily changed.

  In addition, when the throttle part that restricts the flow rate of the refrigerating machine oil in the groove communication path (85) is configured by the rod-like member (89) having the spiral groove (89e) formed on the outer peripheral part as described above, a sufficient throttle effect In order to obtain this, it is necessary to lengthen the length of the narrow passage formed by the spiral groove (89e) to some extent. However, if the length of the rod-shaped member (89) is increased to increase the length of the narrow passage, a long space is required to install the rod-shaped member (89), and there is a risk that the installation work may be time-consuming.

  On the other hand, in this embodiment, since the rod-like member (89) constituting the throttle portion is provided at a plurality of locations in the groove communication path (85), the length of one rod-like member (89) is short. Can also increase the total length of the narrow passage. Therefore, the flow rate of the lubricating oil in the groove communication path (85) can be sufficiently limited. In other words, the length of each rod-shaped member (89) can be shortened by providing the rod-shaped member (89) at a plurality of locations in the groove communication path (85). Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

  Furthermore, in the present embodiment, the third connection passage (83) and the second connection passage (83), which are communication holes forming part of the groove communication passage (85) in both the lower bearing member (55) and the fixed scroll (30), are provided. Since one connecting passage (81) is formed and a rod-like member (89) constituting the throttle portion is provided for each, one rod-like member (89) and a communication hole (the third connecting passage (83) and the first Even if the length of the one connecting passage (81)) is short, the total length of the narrow passage can be increased. Therefore, the flow rate of the refrigerating machine oil in the groove communication path (85) can be sufficiently limited. In other words, communication holes (third connection passage (83) and first connection passage (81)) are formed in both the lower bearing member (55) and the fixed scroll (30), and the rod-like members (89 ) Can be used to shorten the length of each rod-like member (89). Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

  In the present embodiment, the connecting pipe (84) that forms a part of the groove communication path (85) is provided between the casing (15) and the electric motor (50). When the connecting pipe (84) provided on the side of the electric motor (50) is a metal pipe, it is necessary to separate the electric motor (50) from the electric motor (50) by a distance that ensures insulation. The diameter of the casing (15) must be increased by the distance of However, in this embodiment, the connecting pipe (84) provided on the side of the electric motor (50) is constituted by a resin pipe formed of a resin material. Therefore, insulation can be ensured without providing the connecting pipe (84) away from the electric motor (50). Therefore, the diameter of the casing (15) can be reduced. That is, it is possible to reduce the size of the scroll compressor.

  Note that the connecting pipe (84) may not be formed entirely of a resin material as described above, but may be formed of a metal pipe covering only the outer peripheral surface of the metal pipe.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a scroll compressor that compresses a refrigerant or the like.

10 Scroll compressor
15 casing
18 Oil sump
20 Compression mechanism
30 Fixed scroll
35 Fixed-side thrust sliding surface
40 movable scroll
41 Movable end panel (end panel)
45 Movable thrust sliding surface
60 Drive shaft
70 Oil supply passage (oil supply passage for bearings)
75 Oil pump
80 Oil groove
85 Groove communication passage
87 Capillary tube (throttle part)

  The present invention relates to a measure for improving the reliability of a scroll compressor.

  Conventionally, scroll compressors are widely used for compressing refrigerant, air, and the like. For example, Patent Document 1 discloses a hermetic scroll compressor. Here, the structure of the scroll compressor (500) disclosed in Patent Document 1 will be described with reference to FIG.

  In the scroll compressor (500), a compression mechanism (520) and an electric motor (515) are accommodated in a vertically long cylindrical casing (510). The compression mechanism (520) is disposed above the electric motor (515) and is connected to the electric motor (515) via the drive shaft (550).

  The compression mechanism (520) includes a fixed scroll (525), a movable scroll (530), and a housing (540). In the end plate portion (531) of the movable scroll (530), a wrap (532) protrudes from the front surface, and a cylindrical portion (533) protrudes from the rear surface. In the compression mechanism (520), the wrap (532) of the movable scroll (530) meshes with the wrap (526) of the fixed scroll (525) to form the compression chamber (521). Further, the thrust sliding surface (536) of the end plate portion (531) of the movable scroll (530) is in sliding contact with the thrust sliding surface (527) of the fixed scroll (525). The eccentric part (551) of the drive shaft (550) is inserted into the cylindrical part (533) of the movable scroll (530). When the drive shaft (550) rotates, the movable scroll (530) performs a revolving motion, and the refrigerant sucked into the compression chamber (521) is compressed.

  In this scroll compressor (500), an oil supply passage (555) is formed in the drive shaft (550). Lubricating oil that has flowed into the oil supply passage (555) from the bottom of the casing (510) is supplied to the bearing portion from the first branch passage (556) and the second branch passage (557). Further, a part of the lubricating oil flowing through the oil supply passage (555) flows out from the end of the oil supply passage (555) opened at the upper end of the eccentric portion (551).

  The refrigerant pressure in the compression chamber (521) acts on the front surface of the end plate portion (531) of the movable scroll (530). For this reason, when the refrigerant | coolant pressure in a compression chamber (521) rises, the movable scroll (530) will be pushed down and the airtightness of a compression chamber (521) will fall.

  On the other hand, in the scroll compressor (500), a seal ring (541) is provided between the housing (540) and the movable scroll (530). The pressure inside the seal ring (541) is substantially equal to the pressure of the lubricating oil flowing out from the end of the oil supply passageway (555) (and hence the pressure of the refrigerant discharged from the compression mechanism (520)). For this reason, the movable scroll (530) is pushed upward by the pressure acting on the back surface of the end plate portion (531). As a result, the movable scroll (530) is pressed against the fixed scroll (525), and the airtightness of the compression chamber (521) is ensured.

  However, the force that the movable scroll (530) presses against the fixed scroll (525) may become too strong. If this force becomes too strong, the frictional force generated on the thrust sliding surface (536) of the movable scroll (530) and the thrust sliding surface (527) of the fixed scroll (525) will increase, resulting in consumption of the electric motor (515). Power will increase.

  On the other hand, in the scroll compressor (500), an oil groove (534) and a communication path (535) are formed in the end plate portion (531) of the movable scroll (530). The oil groove (534) is a concave groove that opens to the thrust sliding surface (536) of the end plate portion (531), and is formed so as to surround the periphery of the wrap (532).

  The oil groove (534) communicates with the internal space of the cylindrical portion (533) via the communication path (535). Accordingly, the pressure in the oil groove (534) is substantially equal to the pressure of the lubricating oil flowing out from the end of the oil supply passage (555). The pressure in the compression chamber (521) adjacent to the oil groove (534) is approximately the same as the pressure of the low-pressure refrigerant sucked into the compression chamber (521), and is lower than the pressure in the oil groove (534). For this reason, a sufficient amount of lubricating oil is supplied to the thrust sliding surfaces (527,536) due to the pressure difference between the oil groove (534) and the compression chamber (521). As a result, the frictional force generated on the thrust sliding surface (536) of the movable scroll (530) and the thrust sliding surface (527) of the fixed scroll (525) is reduced, and the power consumption of the electric motor (515) can be kept low. .

Japanese Patent No. 3731068

  In the movable scroll (530) of the scroll compressor (500), the internal pressure of the compression chamber (521) acts on the wrap (532) protruding from the front surface of the end plate portion (531) and protrudes from the back surface of the end plate portion (531). A load from the drive shaft (550) acts on the cylindrical portion (533). The gas pressure acting on the wrap (532) and the load acting on the cylindrical portion (533) have their lines of action perpendicular to the axial direction of the movable scroll (530) and do not cross each other. For this reason, a moment to tilt the movable scroll (530) acts on the movable scroll (530).

  If the pressure acting on the back of the end plate (531) (specifically, the pressure inside the seal ring (541)) is sufficiently high, the movable scroll (530) is strongly pressed against the fixed scroll (525). The movable scroll (530) does not tilt even when a moment is applied. However, in an operating state where the pressure acting on the back surface of the end plate (531) is not so high (for example, an operating state where the pressure of the refrigerant discharged from the compression mechanism (520) is very low), the movable scroll (530) is tilted. The clearance between the thrust sliding surface (536) of the movable scroll (530) and the thrust sliding surface (527) of the fixed scroll (525) may increase. In the scroll compressor (500) shown in FIG. 9, when the clearance of the thrust sliding surfaces (527, 536) is increased, the pressure in the oil groove (534) may be rapidly decreased.

  In the conventional scroll compressor (500) shown in FIG. 9, the oil groove (534) communicates with the bearing portion of the compression mechanism (520) via the communication path (535) and the oil supply path (555). For this reason, when the movable scroll (530) is tilted and the pressure in the oil groove (534) rapidly decreases, the pressure in the oil supply passage (555) communicating with the oil groove (534) decreases, and the lubricating oil flows from the bearing portion. There is a risk of backflow through the branch passage (556,557) to the oil supply passage (555). Then, if the lubricating oil flows backward from the bearing portion to the oil supply passageway (555), the bearing portion is not sufficiently lubricated, which may cause troubles such as seizure.

  This invention is made | formed in view of this point, The objective is to improve the reliability of a scroll compressor.

1st invention is accommodated in the casing (15), the compression mechanism (20) which is accommodated in this casing (15), and has a fixed scroll (30) and a movable scroll (40), The said casing (15), A drive shaft (60) engaged with the movable scroll (40), and the compression mechanism (20) discharges the compressed fluid into the casing (15), and the movable scroll (40) The present invention is directed to a scroll compressor configured to generate a pressing force for pressing against a fixed scroll (30). The end plate portion (41) of the movable scroll (40) and the fixed scroll (30) are formed with a movable thrust sliding surface (45) and a fixed thrust sliding surface (35) that are in sliding contact with each other. The movable thrust sliding surface (45) or the fixed thrust sliding surface (35) is formed with an oil groove (80) through which lubricating oil flows, and is not in communication with the oil groove (80). A bearing oil supply passage (70) for supplying lubricating oil in an oil reservoir (18) in the casing (15) to a bearing of the drive shaft (60) provided in the compression mechanism (20); A groove communication passage (85) for connecting the oil groove (80) to an oil reservoir (18) in the casing (15), and the bearing oil supply passage (70) is provided by the drive shaft (60). An oil supply pump (75) that is driven and sucks and discharges lubricating oil from the oil reservoir (18) in the casing (15) is provided. The groove communication passage (85) is configured so that lubricating oil flows only by the pressure difference between the oil reservoir (18) in the casing (15) and the oil groove (80). The passage (85) is provided with a throttle portion for restricting the flow rate of the lubricating oil, and the throttle portion is inserted into the groove communication passage (85) and is a spiral for flowing the lubricating oil to the outer peripheral portion. It is formed by the rod-shaped member (89) in which the groove (89e) is formed .

  In the first invention, when the movable scroll (40) is driven by the drive shaft (60), fluid is sucked into the compression mechanism (20) and compressed. The compression mechanism (20) discharges the compressed fluid into the casing (15). For this reason, the pressure of the lubricating oil stored in the casing (15) is substantially equal to the pressure of the fluid discharged from the compression mechanism (20). The lubricating oil in the casing (15) is supplied to the bearing of the compression mechanism (20) through the bearing oil supply passage (70).

  In the compression mechanism (20) of the first invention, the movable scroll (40) is pressed against the fixed scroll (30) in order to ensure the airtightness of the compression chamber. Further, the movable side thrust sliding surface (45) of the movable scroll (40) and the fixed side thrust sliding surface (35) of the fixed scroll (30) slide with each other. In the compression mechanism (20), an oil groove (80) is formed on the movable thrust sliding surface (45) or the fixed thrust sliding surface (35). The oil groove (80) communicates with the oil reservoir (18) in the casing (15) through the groove communication path (85). For this reason, the pressure of the lubricating oil in the oil groove (80) becomes substantially equal to the pressure of the lubricating oil stored in the casing (15). The lubricating oil that has flowed from the oil reservoir (18) through the groove communication passage (85) into the oil groove (80) is supplied to the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). The

  In the compression mechanism (20) of the first invention, the movable scroll (40) may tilt. In this case, the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) increases, and as a result, the pressure in the oil groove (80) may drop rapidly. On the other hand, in the present invention, the bearing oil supply passage (70) is not in communication with the oil groove (80). For this reason, even if the pressure in the oil groove (80) drops rapidly, the pressure in the bearing oil supply passage (70) does not change.

In the first invention, when the movable scroll (40) tilts during operation of the compression mechanism (20) and the pressure in the oil groove (80) decreases, the lubricating oil in the oil sump (18) is contained in the casing (15). Due to the pressure difference between the oil sump (18) and the oil groove (80), it flows through the groove communication passage (85) toward the oil groove (80). On the other hand, an oil supply pump (75) is provided in the bearing oil supply passage (70). The oil supply pump (75) is driven by the drive shaft (60), and sucks and discharges the lubricating oil from the oil reservoir (18) in the casing (15). Lubricating oil discharged from the oil supply pump (75) is supplied to the bearing of the compression mechanism (20).

By the way, when the movable scroll (40) tilts during the operation of the compression mechanism (20), the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) increases. For this reason, the lubricating oil tends to flow out from the oil groove (80), and the flow rate of the lubricating oil in the groove communication path (85) may be excessive.

On the other hand, in the first invention, the throttle portion is provided in the groove communication path (85). Even in the state where the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) is enlarged, the flow rate of the lubricating oil in the groove communication passage (85) is limited by the throttle portion.

In the first invention, the rod-like member (89) in the groove communication passage (85) is inserted into the groove communication passage (85) by inserting the rod-like member (89) in which the spiral groove (89e) is formed. A spiral narrow passage is formed on the outer peripheral side of the. As a result, the flow rate of the lubricating oil flowing into the groove communication passage (85) is restricted in the spiral narrow passage formed on the outer peripheral side of the rod-like member (89).

In a second aspect based on the first aspect , the bar-shaped member (89) is provided at a plurality of locations of the groove communication path (85).

In the second invention, the bar-like member (89) constituting the throttle portion is provided at a plurality of locations in the groove communication path (85). Here, when only one rod-like member (89) is provided in the groove communication path (85), a certain length of narrow flow path is required to sufficiently limit the flow rate of the lubricating oil, The rod-shaped member (89) must be formed long. However, by providing the rod-shaped members (89) at a plurality of locations in the groove communication passage (85) as described above, even if the length of one rod-shaped member (89) is short, the total length of the narrow passage is become longer.

A third invention includes a bearing (55) provided separately from the compression mechanism (20) and rotatably supporting the drive shaft (60) in the second invention, and the bearing (55) The fixed scroll (30) is formed with communication holes (83, 81) that form a part of the groove communication path (85), and the rod-shaped members (83, 81) are formed in the communication holes (83, 81). 89).

In the third invention, the bearing (55) and the fixed scroll (30) are each formed with a communication hole (83, 81) that forms a part of the groove communication path (85), and each communication hole (83 , 81) are provided with rod-like members (89) constituting the throttle part. Therefore, when one rod-shaped member (89) is provided on either the bearing (55) or the fixed scroll (30), a certain length of narrow flow path is required to sufficiently limit the flow rate of the lubricating oil. Therefore, the rod-shaped member (89) and the communication hole provided with the rod-shaped member (89) must be formed long. However, as described above, by forming the communication holes (83, 81) in both the bearing (55) and the fixed scroll (30) and providing the rod-shaped members (89) respectively, one rod-shaped member (89) And even if the length of the communication hole (83, 81) is short, the total length of the narrow passage becomes long.

According to a fourth invention, in any one of the first to third inventions, an electric motor (50) for rotationally driving the drive shaft (60), and between the casing (15) and the electric motor (50). A connecting pipe (84) that is provided and forms a part of the groove communication path (85). It is comprised by the made metal piping.

In the fourth aspect of the invention, the connecting pipe (84) that forms a part of the groove communication path (85) is provided between the casing (15) and the electric motor (50).

  By the way, when providing a metal pipe on the side of the electric motor (50), it is necessary to separate it from the electric motor (50) by a distance that ensures insulation. Therefore, the diameter of the casing (15) had to be increased by the distance between the electric motor (50) and the pipe.

On the other hand, in 4th invention, the connection pipe (84) is comprised by the resin piping in which the outer peripheral surface was coat | covered with the resin material, or the resin pipe formed with the resin material. Therefore, insulation can be ensured without providing the connecting pipe (84) away from the electric motor (50).

According to a fifth invention, in any one of the first to fourth inventions, the lubricating oil inflow port (88) of the groove communication passage (85) is provided as a lubricating oil of the bearing oil supply passage (70). It is formed above the inflow port (76).

  Part of the lubricating oil supplied from the oil reservoir (18) in the casing (15) to the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) via the oil groove (80) It flows into the compression chamber and is discharged to the outside of the casing (15) together with the compressed refrigerant. For this reason, in the oil sump (18) in the casing (15), the amount of lubricating oil decreases and the oil level decreases. The oil level of the oil reservoir (18) in the casing (15) is greater than the lubricating oil inlet (76) of the bearing oil supply passage (70) and the lubricating oil inlet (88) of the groove communication passage (85). When the pressure drops, the lubricating oil cannot be supplied from the oil reservoir (18) to the bearing of the drive shaft (60) and the oil groove (80).

  If the amount of lubricating oil supplied to the bearing of the drive shaft (60) is insufficient, the bearing may be seized and damaged. On the other hand, if the oil groove (80) is insufficiently lubricated, the frictional force generated on the movable thrust sliding surface (45) of the movable scroll (40) and the fixed thrust sliding surface (35) of the fixed scroll (30) May increase and the power consumption of the motor may increase.

  Here, the insufficient supply amount of the lubricating oil to the bearing of the drive shaft (60) may cause the bearing to be fatally damaged even in a short time, and the compressor may not operate normally. On the other hand, the shortage of lubricating oil supply to the oil groove (80) via the groove communication passage (85) is temporary due to insufficient sealing of the thrust sliding surface (35, 45) for a short time. Will be fatal but not fatal. That is, the shortage of oil supply to the bearing of the drive shaft (60) needs to be taken promptly compared to the shortage of oil supply to the oil groove (80).

In contrast, in the fifth aspect of the invention, the lubricating oil inlet (88) of the groove communication passage (85) is formed above the lubricating oil inlet (76) of the bearing oil supply passage (70). Yes. Therefore, when the amount of lubricating oil in the oil sump (18) in the casing (15) decreases, the oil level of the oil sump (18) first falls below the inlet (88) of the groove communication passage (85), and the oil groove Lubricant is no longer supplied to (80). As a result, the amount of lubricating oil discharged together with the refrigerant to the outside of the casing (15) is reduced, and the oil level of the oil reservoir (18) in the casing (15) is suppressed from being lowered.

  In the first aspect of the invention, the oil groove (80) is formed on the movable thrust sliding surface (45) of the movable scroll (40) or the fixed thrust sliding surface (35) of the fixed scroll (30). Yes. Further, the bearing oil supply passage (70) for supplying lubricating oil to the bearing of the compression mechanism (20) is not in communication with the oil groove (80). For this reason, even if the movable scroll (40) is inclined during the operation of the compression mechanism (20) and the pressure in the oil groove (80) is rapidly reduced, the pressure in the bearing oil supply passage (70) does not change.

  Here, assuming that the oil groove (80) and the bearing oil supply passage (70) are in communication with each other, when the pressure in the oil groove (80) decreases rapidly, the oil supply passage for the bearing (70) The pressure will also decrease. If the pressure in the bearing oil supply passage (70) decreases, the lubricating oil flows backward from the bearing of the compression mechanism (20) to the bearing oil supply passage (70), and there is a risk that the lubricating oil for lubricating the bearing will be insufficient. is there.

  In contrast, in the first aspect of the invention, the bearing oil supply passage (70) is not in communication with the oil groove (80), and even if the pressure in the oil groove (80) is suddenly reduced, the bearing oil supply passage is provided. The pressure of (70) does not change. Therefore, according to the first aspect of the invention, even when the movable scroll (40) is inclined and the pressure in the oil groove (80) is suddenly reduced, the bearing of the compression mechanism (20) to the bearing oil supply passage (70). The lubricating oil does not flow backward, and the lubricating oil can be reliably supplied to the bearing of the compression mechanism (20) through the bearing oil supply passage (70). As a result, the bearing of the compression mechanism (20) can always be lubricated reliably, and troubles such as seizure can be prevented and the reliability of the scroll compressor (10) can be improved.

In the first invention, the lubricating oil discharged from the oil supply pump (75) driven by the drive shaft (60) passes through the bearing oil supply passage (70) that does not communicate with the oil groove (80). Supplied to the bearing of the compression mechanism (20). Therefore, even when the movable scroll (40) is tilted during operation of the compression mechanism (20) and the pressure in the oil groove (80) is suddenly reduced, the lubricating oil is stably supplied to the bearing of the compression mechanism (20). can do. Therefore, according to the present invention, the lubricating oil can be reliably supplied to the bearing of the compression mechanism (20) regardless of the pressure in the oil groove (80), and the reliability of the scroll compressor (10) can be improved. .

In the first invention, the throttle portion is provided in the groove communication path (85). Therefore, even when the movable scroll (40) is tilted and the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) is increased, the flow rate of the lubricating oil in the groove communication passage (85) Is limited by the aperture.

  Here, if the movable scroll (40) tilts during operation of the compression mechanism (20), the lubricating oil passes through the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). The pressure loss is reduced, and the pressure acting on the thrust sliding surface (35, 45) may increase to the same level as the lubricating oil pressure in the oil groove (80). In this case, the force for pulling the movable scroll (40) away from the fixed scroll (30) increases, and the airtightness of the compression chamber (521) may be reduced.

On the other hand, in the first invention, the throttle portion is provided in the groove communication passage (85), and the oil groove (80) is connected to the groove communication passage (85) even when the movable scroll (40) is inclined. The flow rate of the lubricating oil flowing into the water is kept low, and the pressure in the oil groove (80) is kept low. Therefore, even when the movable scroll (40) is tilted during the operation of the compression mechanism (20), the pressure acting on the thrust sliding surfaces (35, 45) is kept low, and the movable scroll (40) is fixed to the fixed scroll (30 The power to pull away from) will not be excessive. On the other hand, a pressing force for pressing the movable scroll (40) against the fixed scroll (30) acts on the movable scroll (40). For this reason, the movable scroll (40) tilted during the operation of the compression mechanism (20) receives this pressing force and quickly returns to its original posture. Therefore, according to the present invention, the movable scroll (40) inclined during the operation of the compression mechanism (20) can be quickly returned to the original posture, and the airtightness of the compression chamber (521) is ensured and scroll compression is ensured. The deterioration of the machine (10) can be suppressed.

In the first aspect of the present invention, the lubrication in the groove communication path (85) can be achieved simply by inserting the rod-shaped member (89) having the spiral groove (89e) formed in the outer peripheral portion into the groove communication path (85). A throttle portion that limits the flow rate of oil can be easily formed. Moreover, the passage sectional area of the groove communication passage (85) can be easily changed only by changing the sectional shape of the spiral groove (89e) on the outer peripheral portion of the rod-like member (89). That is, by configuring the throttle portion with the rod-shaped member (89), the degree of freedom in design is improved and the design can be easily changed.

  In addition, when the throttle member that restricts the flow rate of the lubricating oil in the groove communication passage (85) is configured by the rod-like member (89) having the spiral groove (89e) formed on the outer peripheral portion as described above, a sufficient throttle effect is achieved. In order to obtain this, it is necessary to lengthen the length of the narrow passage formed by the spiral groove (89e) to some extent. However, if the length of the rod-shaped member (89) is increased to increase the length of the narrow passage, a long space is required to install the rod-shaped member (89), and there is a risk that the installation work may be time-consuming.

On the other hand, in the second invention, since the rod-shaped member (89) constituting the throttle portion is provided at a plurality of locations in the groove communication path (85), the length of one rod-shaped member (89) is short. However, the total length of the narrow passage can be increased. Therefore, the flow rate of the lubricating oil in the groove communication path (85) can be sufficiently limited. In other words, the length of each rod-shaped member (89) can be shortened by providing the rod-shaped member (89) at a plurality of locations in the groove communication path (85). Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

In the third aspect of the invention, the communication holes (83, 81) that form part of the groove communication path (85) are formed in both the bearing (55) and the fixed scroll (30), and the restricting portions are respectively provided. Since the rod-shaped member (89) is provided, the total length of the narrow passage can be increased even if the length of one rod-shaped member (89) and the communication hole (83, 81) is short. Therefore, the flow rate of the lubricating oil in the groove communication path (85) can be sufficiently limited. In other words, the communication holes (83, 81) are formed in both the bearing (55) and the fixed scroll (30), and the rod-shaped members (89) are provided in each, thereby reducing the length of each rod-shaped member (89). Can be shortened. Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

In the fourth invention, the connecting pipe (84) provided between the casing (15) and the electric motor (50) and forming a part of the groove communication path (85) is formed of a resin material. The resin pipe or the outer peripheral surface is constituted by a metal pipe covered with a resin material. Thereby, since insulation can be secured without providing the connecting pipe (84) away from the electric motor (50), the diameter of the casing (15) can be reduced. That is, it is possible to reduce the size of the scroll compressor.

In the fifth aspect of the invention, the lubricating oil inlet (88) of the groove communication passage (85) is provided above the lubricating oil inlet (76) of the bearing oil supply passage (70). For this reason, even if the oil level of the oil sump (18) in the casing (15) decreases, the lubricating oil is first not supplied to the oil groove (80), so that it is discharged together with the refrigerant to the outside of the casing (15). The amount of lubricating oil is reduced. As a result, a decrease in the oil level of the oil sump (18) in the casing (15) is suppressed. Therefore, according to the fifth aspect , even if the oil level of the oil sump (18) in the casing (15) starts to decrease, the oil level is suppressed by stopping the oil supply to the oil groove (80). be able to. As a result, the oil level in the oil reservoir (18) in the casing (15) is prevented from lowering to a position below the lubricating oil inlet (76) in the bearing oil supply passage (70). It is possible to ensure oil supply to the bearing of the drive shaft (60). That is, giving priority to oil supply to the bearing of the drive shaft (60) over oil supply to the oil groove (80) can prevent fatal damage to the bearing due to seizure of the bearing of the drive shaft (60).

It is a longitudinal cross-sectional view which shows the whole structure of the scroll compressor of the reference form 1 . It is a longitudinal cross-sectional view which shows the structure of the principal part of the scroll compressor of the reference form 1 . It is a cross-sectional view which shows the structure of the compression mechanism of the scroll compressor of the reference form 1 . It is a longitudinal cross-sectional view which shows the structure of the principal part of the scroll compressor of the reference form 2 . It is a longitudinal section showing the whole structure of the scroll compressor of an embodiment . It is a longitudinal cross-sectional view which shows the structure of the 1st and 2nd connection channel | path of the scroll compressor of embodiment . It is a longitudinal cross-sectional view which shows the structure of the 3rd connection channel | path of the scroll compressor of embodiment . It is a longitudinal cross-sectional view which shows the structure of the connecting pipe of the scroll compressor of embodiment . It is a longitudinal cross-sectional view which shows the structure of the principal part of the conventional scroll compressor.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<< Reference Form 1 of the Invention >>
Reference Embodiment 1 of the present invention will be described. The scroll compressor (10) of this reference form is a hermetic compressor. The scroll compressor (10) is connected to a refrigerant circuit that performs a refrigeration cycle, and sucks and compresses refrigerant in the refrigerant circuit.

<Overall configuration of scroll compressor>
As shown in FIG. 1, in the scroll compressor (10), a compression mechanism (20), an electric motor (50), a lower bearing member (55), and a drive shaft (60) are provided in the internal space of the casing (15). And is housed. The casing (15) is a sealed container formed in a vertically long cylindrical shape. In the internal space of the casing (15), a compression mechanism (20), an electric motor (50), and a lower bearing member (55) are arranged in order from the top to the bottom. Further, the drive shaft (60) is arranged in such a posture that its axial direction is along the height direction of the casing (15). The detailed structure of the compression mechanism (20) will be described later.

  A suction pipe (16) and a discharge pipe (17) are attached to the casing (15). The suction pipe (16) and the discharge pipe (17) both penetrate the casing (15). The suction pipe (16) is connected to the compression mechanism (20). The discharge pipe (17) opens in a portion between the electric motor (50) and the compression mechanism (20) in the internal space of the casing (15).

  The lower bearing member (55) includes a central cylindrical portion (56) and an arm portion (57). Although only one is shown in FIG. 1, the lower bearing member (55) is provided with three arms (57). The central cylindrical portion (56) is formed in a substantially cylindrical shape. Each arm portion (57) extends outward from the outer peripheral surface of the central cylindrical portion (56). In the lower bearing member (55), the three arm portions (57) are arranged at substantially equal angular intervals. The protruding end portion of each arm portion (57) is fixed to the casing (15). Near the upper end of the central cylindrical portion (56), a bearing metal (58) is inserted. A sub journal portion (67) of a drive shaft (60), which will be described later, is inserted through the bearing metal (58). The central cylindrical portion (56) constitutes a journal bearing that supports the sub journal portion (67).

  The electric motor (50) includes a stator (51) and a rotor (52). The stator (51) is fixed to the casing (15). The rotor (52) is arranged coaxially with the stator (51). A main shaft portion (61) of a drive shaft (60), which will be described later, is inserted through the rotor (52).

  The drive shaft (60) is formed with a main shaft portion (61), a balance weight portion (62), and an eccentric portion (63). The balance weight part (62) is disposed in the middle of the main shaft part (61) in the axial direction. The main shaft portion (61) has a lower portion than the balance weight portion (62) passing through the rotor (52) of the electric motor (50). Further, in the main shaft portion (61), the portion above the balance weight portion (62) constitutes the main journal portion (64), and the sub journal portion (67) below the portion penetrating the rotor (52). ) Is formed. The main journal portion (64) is inserted through a bearing metal (28) provided in the central bulge portion (27) of the housing (25). The sub-journal part (67) is inserted through a bearing metal (58) provided in the central cylindrical part (56) of the lower bearing member (55).

  The eccentric part (63) is formed in a cylindrical shape having a smaller diameter than the main journal part (64), and projects from the upper end surface of the main journal part (64). The shaft center of the eccentric portion (63) is parallel to the shaft center of the main journal portion (64) (that is, the shaft center of the main shaft portion (61)) and is eccentric to the shaft center of the main journal portion (64). Yes. The eccentric part (63) is inserted into a bearing metal (44) provided in the cylindrical part (43) of the movable scroll (40).

  An oil supply passage (77) is formed in the drive shaft (60). The oil supply passage (77) includes one main passage (74) and three branch passages (71 to 73). The main passage (74) extends along the axis of the drive shaft (60), and one end thereof opens to the lower end of the main shaft portion (61) and the other end opens to the upper end surface of the eccentric portion (63). ing. The first branch passage (71) is formed in the eccentric part (63). The first branch passage (71) extends from the main passage (74) to the outer side in the radial direction of the eccentric portion (63), and is open to the outer peripheral surface of the eccentric portion (63). The second branch passage (72) is formed in the main journal portion (64). The second branch passage (72) extends from the main passage (74) to the outer side in the radial direction of the main journal portion (64), and opens on the outer peripheral surface of the main journal portion (64). The third branch passage (73) is formed in the secondary journal section (67). The third branch passage (73) extends from the main passage (74) to the outer side in the radial direction of the sub journal portion (67), and is open to the outer peripheral surface of the sub journal portion (67).

  An oil supply pump (75) is attached to the lower end of the drive shaft (60). The oil supply pump (75) is a trochoid pump driven by the drive shaft (60). The oil supply pump (75) is disposed near the start end of the main passage (74) of the oil supply passage (77). In addition, the oil supply pump (75) has a suction port (76) that opens downward at the lower end and sucks refrigeration oil, which is lubricating oil. The oil supply pump (75) is not limited to the trochoid pump, and may be a positive displacement pump driven by the drive shaft (60). Therefore, the oil supply pump (75) may be a gear pump, for example. The oil supply pump (75) and the oil supply passage (77) constitute a bearing oil supply passage (70) for supplying refrigeration oil to a journal bearing of the compression mechanism (20) described later. In addition, the suction port (76) of the oil supply pump (75) constitutes a refrigerating machine oil inlet of the bearing oil supply passage (70).

  Refrigerating machine oil, which is lubricating oil, is stored at the bottom of the casing (15). That is, an oil sump (18) is formed at the bottom of the casing (15). When the drive shaft (60) rotates, the oil supply pump (75) sucks and discharges refrigeration oil from the oil reservoir (18), and the refrigeration oil discharged from the oil supply pump (75) flows through the main passage (74). The refrigeration oil flowing through the main passage (74) is supplied to the lower bearing member (55), the compression mechanism (20), and the sliding portion of the drive shaft (60). Since the oil supply pump (75) is a positive displacement pump, the flow rate of the refrigeration oil in the main passage (74) is proportional to the rotational speed of the drive shaft (60).

<Configuration of compression mechanism>
As shown also in FIG. 2, the compression mechanism (20) includes a housing (25), a fixed scroll (30), and a movable scroll (40). The compression mechanism (20) is provided with an Oldham coupling (24) for restricting the rotation of the movable scroll (40).

  The housing (25) is formed in a thick disk shape, and its outer peripheral edge is fixed to the casing (15). A central concave portion (26) and an annular convex portion (29) are formed in the central portion of the housing (25). The central recess (26) is a cylindrical recess that opens on the upper surface of the housing (25). The annular convex portion (29) is formed along the outer periphery of the central concave portion (26) and protrudes from the upper surface of the housing (25). The protruding end surface of the annular convex portion (29) is a flat surface. A ring-shaped concave groove is formed along the circumferential direction of the projecting end surface of the annular convex portion (29), and a seal ring (29a) is fitted into the concave groove.

  A central bulge portion (27) is formed in the housing (25). The central bulging portion (27) is located below the central concave portion (26) and bulges downward. A through-hole penetrating the central bulge portion (27) vertically is formed in the central bulge portion (27), and a bearing metal (28) is inserted into the through-hole. The main journal portion (64) of the drive shaft (60) is inserted through the bearing metal (28) of the central bulge portion (27). The central bulge portion (27) constitutes a journal bearing that supports the main journal portion (64).

  A fixed scroll (30) and a movable scroll (40) are placed on the housing (25). The fixed scroll (30) is fixed to the housing (25) with bolts or the like. On the other hand, the movable scroll (40) is engaged with the housing (25) via the Oldham coupling (24), and is movable relative to the housing (25). The movable scroll (40) engages with the drive shaft (60) to make a revolving motion.

  The movable scroll (40) is a member in which a movable side end plate portion (41), a movable side wrap (42), and a cylindrical portion (43) are integrally formed. The movable side end plate portion (41) is formed in a disc shape. The movable side wrap (42) is formed in a spiral wall shape, and protrudes from the front surface (upper surface in FIGS. 1 and 2) of the movable side end plate portion (41). The cylindrical portion (43) is formed in a cylindrical shape, and protrudes from the back surface (the lower surface in FIGS. 1 and 2) of the movable side end plate portion (41).

  The back surface of the movable side end plate portion (41) of the movable scroll (40) is in sliding contact with a seal ring (29a) provided on the annular convex portion (29) of the housing (25). On the other hand, the cylindrical portion (43) of the movable scroll (40) is inserted from above into the central recess (26) of the housing (25). A bearing metal (44) is inserted into the cylindrical portion (43). An eccentric portion (63) of the drive shaft (60) described later is inserted into the bearing metal (44) of the cylindrical portion (43) from below. The cylindrical portion (43) constitutes a journal bearing that slides with the eccentric portion (63).

  The fixed scroll (30) is a member in which a fixed side end plate portion (31), a fixed side wrap (32), and an outer peripheral portion (33) are integrally formed. The fixed side end plate portion (31) is formed in a disc shape. The fixed side wrap (32) is formed in a spiral wall shape, and protrudes from the front surface (the lower surface in FIGS. 1 and 2) of the fixed side end plate portion (31). The outer peripheral portion (33) is formed in a thick ring shape extending downward from the outer peripheral portion (33) of the fixed-side end plate portion (31) and surrounds the fixed-side wrap (32).

  A discharge port (22) is formed in the fixed side end plate portion (31). The discharge port (22) is a through hole formed in the vicinity of the center of the fixed-side end plate portion (31), and passes through the fixed-side end plate portion (31) in the thickness direction. A suction pipe (16) is inserted in the vicinity of the outer periphery of the fixed-side end plate part (31).

  A discharge gas passage (23) is formed in the compression mechanism (20). The start end of the discharge gas passage (23) communicates with the discharge port (22). Although not shown, the discharge gas passage (23) is formed from the fixed scroll (30) to the housing (25), and the other end opens to the lower surface of the housing (25).

  In the compression mechanism (20), the fixed scroll (30) and the movable scroll (40) have the front surface of the fixed side end plate portion (31) and the front surface of the movable side end plate portion (41) facing each other, and the fixed side wrap (32) The movable wraps (42) are arranged so as to mesh with each other. In the compression mechanism (20), the fixed wrap (32) and the movable wrap (42) mesh with each other to form a plurality of compression chambers (21).

  In the compression mechanism (20), the movable side end plate portion (41) of the movable scroll (40) and the outer peripheral portion (33) of the fixed scroll (30) are in sliding contact with each other. Specifically, in the movable side end plate portion (41), a portion of the front surface (upper surface in FIGS. 1 and 2) on the outer peripheral side of the movable side wrap (42) is in sliding contact with the fixed scroll (30). Thrust sliding surface (45). On the other hand, the outer peripheral portion (33) of the fixed scroll (30) has its protruding end surface (the lower surface in FIGS. 1 and 2) in sliding contact with the movable thrust sliding surface (45) of the movable scroll (40). In the outer peripheral portion (33), a portion of the protruding end surface that is in sliding contact with the movable side thrust sliding surface (45) is a fixed side thrust sliding surface (35).

  As shown in FIGS. 2 and 3, an oil groove (80) and a connection passage (86) are formed in the outer peripheral portion (33) of the fixed scroll (30). The oil groove (80) is a concave groove formed in the fixed-side thrust sliding surface (35) of the outer peripheral portion (33), and is formed in a ring shape surrounding the periphery of the fixed-side wrap (32). One end of the connection passage (86) communicates with the oil groove (80). The connecting passage (86) is a passage extending from one end thereof toward the outer periphery of the outer peripheral portion (33). A capillary tube (87), which will be described later, is connected to the vicinity of the other end of the connection passage (86). The connection passage (86) and the capillary tube (87) constitute a groove communication passage (85).

  The capillary tube (87) is a thin copper tube having an inner diameter of about 0.5 to 1.0 mm, and constitutes a throttle portion. The capillary tube (87) is provided along the inner surface of the casing (15). Specifically, the upper end portion of the capillary tube (87) is inserted into a through hole formed in the housing (25) and is inserted into the outer peripheral portion (33) of the fixed scroll (30) to be connected to the connection passage (86). Communicate. The capillary tube (87) is inserted through a core cut portion formed in the stator (51) of the electric motor (50) and extends to the oil reservoir (18). That is, the lower end of the capillary tube (87) is immersed in the refrigerating machine oil stored at the bottom of the casing (15).

The lower end opening (88) of the capillary tube (87) constitutes an inflow port through which the refrigeration oil flows into the groove communication passage (85). The lower end opening (88) of the capillary tube (87) is formed above the suction port (76) of the oil supply pump (75). In this reference embodiment, the lower end opening (88) of the capillary tube (87) is formed at a height position about 10 mm above the suction port (76) of the oil supply pump (75). That is, the inlet of the groove communication passage (85) is formed above the inlet of the refrigerating machine oil in the bearing oil supply passage (70).

In this reference embodiment, the groove communication passage (85) constituted by the connection passage (86) and the capillary tube (87) has the oil groove (80) only in the oil reservoir (18) in the casing (15). Connected. Thus, in this preferred embodiment, the oil supply passage formed in the drive shaft (60) (77) has a non-communicated state and formed in the fixed scroll (30) the oil groove (80). That is, the bearing oil supply passage (70) is not in communication with the oil groove (80).

-Driving action-
The operation of the scroll compressor (10) will be described.

<Operation to compress refrigerant>
In the scroll compressor (10), when the electric motor (50) is energized, the movable scroll (40) is driven by the drive shaft (60). The orbiting scroll (40) has its rotation motion restricted by the Oldham coupling (24), and does not rotate but only revolves.

  When the orbiting scroll (40) revolves, the low-pressure gas refrigerant that has flowed into the compression mechanism (20) through the suction pipe (16) becomes the outer peripheral side of the fixed side wrap (32) and the movable side wrap (42). It is sucked into the compression chamber (21) from near the end. When the movable scroll (40) is further moved, the compression chamber (21) is closed from the suction pipe (16), and then the compression chamber (21) is separated from the fixed wrap (32) and the movable wrap ( 42) and move toward the inner circumferential edge. In the process, the volume of the compression chamber (21) gradually decreases, and the gas refrigerant in the compression chamber (21) is compressed.

  As the volume of the compression chamber (21) gradually decreases as the movable scroll (40) moves, the compression chamber (21) eventually communicates with the discharge port (22). Then, the refrigerant compressed in the compression chamber (21) (that is, high-pressure gas refrigerant) flows into the discharge gas passage (23) through the discharge port (22), and then the internal space of the casing (15). Is discharged. In the internal space of the casing (15), the high-pressure gas refrigerant discharged from the compression mechanism (20) is once guided below the stator (51) of the electric motor (50), and then the rotor (52) And flows through the gap between the stator (51) and the like, and flows out of the casing (15) through the discharge pipe (17).

  The high pressure gas refrigerant discharged from the compression mechanism (20) circulates in the inner space of the casing (15) below the housing (25), and the pressure is substantially equal to the pressure of the high pressure gas refrigerant. Are equal. Therefore, the pressure of the refrigerating machine oil stored in the oil sump (18) in the casing (15) is also substantially equal to the pressure of the high-pressure gas refrigerant.

  On the other hand, the portion of the internal space of the casing (15) above the housing (25) communicates with the suction pipe (16) (not shown), and the low pressure gas whose pressure is sucked into the compression mechanism (20) It is about the same as the pressure of the refrigerant. Therefore, in the compression mechanism (20), the pressure in the space near the outer periphery of the movable side end plate portion (41) of the movable scroll (40) is approximately the same as the pressure of the low-pressure gas refrigerant.

<Oil supply operation for compression mechanism>
During operation of the scroll compressor (10), the oil supply pump (75) is driven by the rotating drive shaft (60), and the refrigerating machine oil stored at the bottom of the casing (15) is the main passage of the oil supply passage (77). Sucked up to (74). A part of the refrigerating machine oil flowing through the main passage (74) flows into the branch passages (71 to 73), and the rest flows out from the upper end of the main passage (74).

  The refrigerating machine oil flowing into the first branch passage (71) is supplied to the gap between the eccentric portion (63) and the bearing metal (44), and is used for lubrication and cooling of the eccentric portion (63) and the bearing metal (44). . The refrigeration oil that flows into the second branch passage (72) is supplied to the gap between the main journal (64) and the bearing metal (28), and is used for lubrication and cooling of the main journal (64) and the bearing metal (28). Is done. The refrigeration oil that has flowed into the third branch passage (73) is supplied to the gap between the sub journal (67) and the bearing metal (58), and is used for lubrication and cooling of the sub journal (67) and the bearing metal (58). Is done. In the compression mechanism (20), the refrigeration oil is also supplied to the sliding portion of the movable scroll (40) and the Oldham coupling (24) and the sliding portion of the movable scroll (40) and the fixed scroll (30).

<Operation of pressing the movable scroll>
Compression mechanism of this preferred embodiment (20) utilizes the refrigeration oil supplied from the oil reservoir in the casing (15) (18) is configured so as to press the fixed scroll and the movable scroll (40) (30) ing.

Specifically, in the compression mechanism (20), the back surface of the movable side end plate portion (41) is in sliding contact with the seal ring (29a). Refrigerating machine oil flowing out from the end of the main passage (74) of the oil supply passage (77) exists in the central recess (26) located inside the seal ring (29a). The pressure of the refrigerating machine oil is approximately the same as the pressure of the refrigerating machine oil in the oil reservoir (18). The movable scroll (40) flows out of the main passage (74) into the portion of the back surface of the movable side end plate portion (41) located inside the seal ring (29a) and the surface of the cylindrical portion (43). The pressure of the refrigerating machine oil acted. Therefore, the movable scroll (40), pressing force is applied force toward the fixed scroll (30) side (in the present reference embodiment upward force) is. As a result, the movable scroll (40) is pressed against the fixed scroll (30) even during the operation of the compression mechanism (20), and the airtightness of the compression chamber (21) is ensured.

  However, the pressing force acting on the movable scroll (40) may become too strong. If the pressing force becomes too strong, the frictional force acting between the movable scroll (40) and the fixed scroll (30) increases, and the power consumption of the electric motor (50) increases.

In contrast, in this preferred embodiment the scroll compressor (10), an oil groove through the groove communication passage (85) (80) is in communication with the casing (15) oil in the reservoir (18), oil The groove (80) is filled with high-pressure refrigeration oil. On the other hand, the pressure in the compression chamber (21) adjacent to the oil groove (80) (that is, the compression chamber (21) formed near the outermost periphery of the wrap (32, 42)) is sucked into the compression chamber (21). The pressure of the low-pressure refrigerant is lower than the pressure of the refrigeration oil in the oil groove (80). Therefore, the refrigerating machine oil in the oil groove (80) gradually flows out into the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35), and these thrust sliding surfaces (35, 45 ) Used for lubrication.

Thus, in this preferred embodiment the scroll compressor (10), refrigeration oil is surely supplied into the gap the thrust sliding surface (45) and the thrust sliding surface (35). For this reason, even when the movable scroll (40) is strongly pressed against the fixed scroll (30), the frictional force generated on the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) becomes excessive. There is nothing.

<Operation when the movable scroll is tilted>
In the movable scroll (40) of the scroll compressor (10), the internal pressure of the compression chamber (21) acts on the movable side wrap (42) protruding from the front surface of the movable side end plate (41), and the movable end plate (41) The load from the eccentric part (63) acts on the cylindrical part (43) projecting from the back surface of. The line of action of the gas pressure acting on the movable side wrap (42) and the load acting on the cylindrical portion (43) are perpendicular to the axial direction of the movable scroll (40) and do not intersect each other. For this reason, during the operation of the compression mechanism (20), a moment is generated to tilt the movable scroll (40). If the pressing force acting on the movable scroll (40) is sufficiently large, the movable scroll (40) will not tilt even if such a moment is applied.

  However, in an operation state in which sufficient pressing force cannot be obtained, the movable scroll (40) may tilt, and the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) may increase. For example, an operating state where the pressure difference between the low pressure gas refrigerant sucked into the compression mechanism (20) and the high pressure gas refrigerant discharged from the compression mechanism (20) is small, or the rotational speed of the drive shaft (60) becomes very low ( In an operating state (for example, about 10 to 20 revolutions per second), there is a possibility that sufficient pressing force cannot be obtained.

  As described above, in the compression mechanism (20), the pressure in the space near the outer periphery of the movable side end plate portion (41) is approximately the same as the pressure of the low-pressure gas refrigerant sucked into the compression mechanism (20). On the other hand, if the movable scroll (40) tilts and the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) increases, the refrigeration oil in the gap between these thrust sliding surfaces (35, 45). The distribution resistance of is reduced. For this reason, when the movable scroll (40) is inclined, a large amount of refrigerating machine oil may be ejected from the oil groove (80) to the space near the outer periphery of the movable side end plate (41).

  In addition, when the movable scroll (40) is tilted, the pressure loss when the refrigeration oil passes through the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) decreases, and the thrust sliding surface The pressure acting on (35,45) may rise to the same level as the pressure of the refrigeration oil in the oil groove (80). In this case, the force for pulling the movable scroll (40) away from the fixed scroll (30) increases, and the airtightness of the compression chamber (521) may be reduced.

In contrast, in this preferred embodiment the scroll compressor (10), capillary tube (87) is provided in the groove communication passage (85). Even when the movable scroll (40) is inclined to increase the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35), the flow rate of the refrigerating machine oil in the groove communication passage (85) is Limited by the capillary tube (87).

Thus, in the compression mechanism of the present reference embodiment (20), even in a state where the movable scroll (40) is inclined, the flow rate of refrigerating machine oil flowing is suppressed low from the groove communication passage (85) into the oil groove (80) The pressure in the oil groove (80) can be kept low. Therefore, even when the movable scroll (40) is tilted during the operation of the compression mechanism (20), the pressure acting on the thrust sliding surfaces (35, 45) is kept low, and the movable scroll (40) is fixed to the fixed scroll (30 The power to pull away from) will not be excessive. On the other hand, a pressing force for pressing the movable scroll (40) against the fixed scroll (30) acts on the movable scroll (40). For this reason, the movable scroll (40) tilted during the operation of the compression mechanism (20) receives this pressing force and quickly returns to its original posture.

  Here, when the pressure loss from the one end of the groove communication passage (85) to the other end is too low, the movable scroll (40) is inclined and the pressure in the oil groove (80) is reduced. The flow rate of the refrigerating machine oil in the communication passage (85) increases rapidly, and a large amount of refrigerating machine oil is ejected from the end of the groove communication path (85). On the other hand, if the pressure loss between the refrigeration oil from one end of the groove communication passage (85) to the other end is too high, the pressure in the oil groove (80) will be sufficiently high after the tilt of the movable scroll (40) is eliminated. It takes a long time to rise, and there is a risk that the amount of refrigerating machine oil supplied to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) will be insufficient.

Therefore, in this preferred embodiment, it constitutes passages for connecting the groove communication passage (85) and (86) by the capillary tube (87). In this reference embodiment, the inner diameter and length of the capillary tube (87) are set so that the pressure loss from the one end of the groove communication passage (85) to the other end of the refrigerating machine oil becomes an appropriate value. The

<Operation to suppress oil level drop in oil reservoir>
In the scroll compressor of this preferred embodiment as described above (10), refrigeration oil in the oil groove (80) is slightly to the gap between the thrust sliding surface (45) and the thrust sliding surface (35) It flows out one by one and is used to lubricate these thrust sliding surfaces (35, 45). Part of the refrigerating machine oil used for lubrication flows into the compression chamber (21) adjacent to the oil groove (80), is discharged into the internal space of the casing (15) together with the gas refrigerant, and is scattered into the internal space. . The refrigerating machine oil scattered in the internal space of the casing (15) is once led downward from the stator (51) of the electric motor (50) together with the gas refrigerant, and partly falls and accumulates in the oil sump (18). The remainder flows together with the gas refrigerant through the gap between the rotor (52) and the stator (51), etc., and is discharged to the outside of the casing (15) through the discharge pipe (17).

  The refrigerating machine oil discharged to the outside of the casing (15) together with the gas refrigerant as described above circulates in the refrigerant circuit to which the scroll compressor (10) is connected together with the refrigerant, and is sucked into the scroll compressor (10) again. The The refrigerating machine oil drawn into the scroll compressor (10) is discharged into the internal space of the casing (15) together with the compressed gas refrigerant, and a part thereof is returned to the oil reservoir (18) in the casing (15).

  By the way, depending on the operation state, the refrigeration oil may not be easily returned into the casing (15) of the scroll compressor (10). For example, if the temperature of the evaporator is low, the viscosity of the refrigerating machine oil increases, and the refrigerating machine oil is likely to accumulate in the evaporator, making it difficult to return to the scroll compressor (10). If such an operating state continues, the amount of refrigerating machine oil discharged together with the gas refrigerant from the casing (15) becomes larger than the amount of refrigerating machine oil returned to the casing (15), and the refrigerating machine oil in the oil reservoir (18) The amount decreases and the oil level decreases. And the oil level of the oil sump (18) in the casing (15) is the suction port (76) of the oil supply pump (75) (refrigerating machine oil inlet of the bearing oil supply passage (70)) and the capillary tube (87). If it drops below the lower end opening (88) (refrigerant oil inlet of the groove communication passage (85)), the oil pool (18) freezes into the journal bearing and oil groove (80) of the compression mechanism (20). Machine oil cannot be supplied.

  If the supply amount of refrigeration oil to the journal bearing of the compression mechanism (20) is insufficient, the journal bearing may be damaged by seizure. On the other hand, if the oil groove (80) is insufficiently lubricated, the frictional force generated on the movable thrust sliding surface (45) of the movable scroll (40) and the fixed thrust sliding surface (35) of the fixed scroll (30) May increase and the power consumption of the motor may increase.

  Here, the shortage of the supply amount of the refrigerating machine oil to the bearing of the drive shaft (60) may fatally damage the journal bearing even in a short time, and the compressor may not operate normally. On the other hand, insufficient supply of refrigerating machine oil to the oil groove (80) may cause fatal damage, although performance will be temporarily reduced due to insufficient sealing of the thrust sliding surface (35, 45) for a short time. There is no. That is, the shortage of oil supply to the journal bearing of the compression mechanism (20) needs to be taken promptly compared to the shortage of oil supply to the oil groove (80).

In contrast, this preferred embodiment the scroll compressor of the (10), the lower end opening (88) is oil supply passage for the bearing of the capillary tube is the inlet of the refrigerating machine oil groove communication passage (85) (87) (70) It is provided above the suction port (76) of the oil supply pump (75) that is the inlet of the refrigerating machine oil. As a result, when the amount of refrigerating machine oil in the oil sump (18) in the casing (15) decreases, the oil level of the oil sump (18) first falls below the lower end opening (88) of the capillary tube (87), and the oil groove ( Refrigerating machine oil will not be supplied to 80). Thus, even if the oil level of the oil sump (18) in the casing (15) decreases, first, the refrigerating machine oil is not supplied to the oil groove (80), so that the refrigerant and the outside of the casing (15) are removed. The amount of refrigerating machine oil discharged is reduced. As a result, the amount of refrigerating machine oil discharged to the outside of the casing (15) exceeds the amount of refrigerating machine oil returned to the casing (15), and the oil level of the oil sump (18) in the casing (15) is suppressed. Is done. As a result, the oil level of the oil reservoir (18) in the casing (15) can be prevented from lowering to a position below the suction port (76) of the bearing oil supply passage (70). It is possible to secure oil supply to the journal bearing of the compression mechanism (20).

-Effect of Reference Form 1-
In this preferred embodiment, the oil groove (80) is formed in the fixed side thrust sliding surface of the fixed scroll (30) (35). Further, the bearing oil supply passage (70) for supplying the refrigeration oil to the journal bearing of the compression mechanism (20) is not in communication with the oil groove (80). For this reason, even if the movable scroll (40) is inclined during the operation of the compression mechanism (20) and the pressure in the oil groove (80) is rapidly reduced, the pressure in the bearing oil supply passage (70) does not change.

  Here, assuming that the oil groove (80) and the bearing oil supply passage (70) are in communication with each other, when the pressure in the oil groove (80) decreases rapidly, the oil supply passage for the bearing (70) The pressure will also decrease. When the pressure in the bearing oil supply passage (70) decreases, the refrigerating machine oil flows backward from the journal bearing of the compression mechanism (20) to the bearing oil supply passage (70), and the refrigerating machine oil for lubricating the journal bearing is insufficient. There is a fear.

In contrast, in this preferred embodiment, bearing oil supply passage (70) is not in communication with the oil groove (80), even if the pressure is rapidly reduced in the oil groove (80), bearing oil supply passage (70 ) Pressure does not change. Therefore, frozen according to this preferred embodiment, even if the pressure of the oil groove inclined movable scroll (40) (80) is suddenly reduced, bearing oil supply passage from the journal bearing of the compression mechanism (20) to (70) The machine oil does not flow backward, and the refrigeration oil can be reliably supplied to the journal bearing of the compression mechanism (20) through the bearing oil supply passage (70). As a result, the journal bearing of the compression mechanism (20) can always be reliably lubricated, and troubles such as seizure can be prevented and the reliability of the scroll compressor (10) can be improved.

Further, according to the reference embodiment, the drive shaft (60) the refrigerating machine oil discharged from the driven oil pump (75) by the, through the oil groove (80) bearing oil supply passage does not communicate with the (70), compression Supplied to the journal bearing of the mechanism (20). Therefore, refrigeration oil is stably supplied to the bearing of the compression mechanism (20) even when the movable scroll (40) is tilted during operation of the compression mechanism (20) and the pressure in the oil groove (80) is suddenly reduced. can do. Therefore, according to this preferred embodiment, it can be reliably supplied to the journal bearing of the oil groove regardless of the pressure (80) refrigeration oil compression mechanism (20) can be reliably avoid problems such as seizure of the journal bearing.

  As described above, when the pressure loss from the one end of the groove communication passage (85) to the other end of the refrigerator oil is too low, the movable scroll (40) is inclined and the movable thrust sliding surface (45) When the clearance of the fixed-side thrust sliding surface (35) is increased, a large amount of refrigeration oil is ejected from the end of the groove communication passage (85). Also, if the pressure loss between the refrigeration oil and one end of the groove communication passage (85) is too high, the pressure in the oil groove (80) is sufficient after the tilt of the movable scroll (40) is eliminated. It takes a long time to rise, and the supply amount of the refrigerating machine oil to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) may be insufficient.

On the other hand, in this reference embodiment, a part of the groove communication path (85) is constituted by the capillary tube (87), and the pressure loss between the refrigerating machine oil from one end of the groove communication path (85) to the other end Is set to an appropriate value. For this reason, even when the movable scroll (40) is inclined, it is possible to prevent the flow rate of the refrigerating machine oil in the groove communication path (85) from becoming excessive. As a result, even when the movable scroll (40) is tilted, the pressure in the oil groove (80) is kept low by restricting the flow rate of the refrigerating machine oil flowing into the oil groove (80) from the groove communication path (85). Thus, the tilted movable scroll (40) can be quickly returned to the original posture. When the movable scroll (40) returns to its original position, the pressure in the oil groove (80) is quickly increased to move the movable-side thrust sliding surface (45) and the fixed-side thrust sliding surface (35). The amount of oil supply to the gap can be ensured.

In this preferred embodiment the scroll compressor (10), the lower end opening (88) is oil supply passage for the bearing of the capillary tube is the inlet of the refrigerating machine oil groove communication passage (85) (87) of the refrigerating machine oil (70) It is provided above the suction port (76) of the oil supply pump (75) that is the inflow port. Therefore, even if the oil level of the oil sump (18) in the casing (15) decreases, first, the refrigerating machine oil is not supplied to the oil groove (80), so that it is discharged together with the refrigerant to the outside of the casing (15). Refrigerating machine oil amount is reduced. As a result, the amount of refrigerating machine oil discharged to the outside of the casing (15) exceeds the amount of refrigerating machine oil returned to the casing (15), and the oil level of the oil sump (18) in the casing (15) is suppressed. Is done. Therefore, according to the scroll compressor (10) of this preferred embodiment, even begins to decrease oil level of the oil reservoir in the casing (15) (18), to stop the supply of refrigeration oil to the oil groove (80) As a result, the oil level can be prevented from lowering so that the oil level of the oil reservoir (18) does not fall below the inlet (88) of the oil supply pump (75), and the journal of the compression mechanism (20) Oil supply to the bearing can be ensured. That is, fatal damage to the journal bearing can be prevented by giving priority to the oil supply to the journal bearing of the compression mechanism (20) over the oil supply to the oil groove (80).

<< Reference Form 2 of the Invention >>
Reference Embodiment 2 of the present invention will be described. Here, regarding the scroll compressor (10) of the present reference embodiment, differences from the reference embodiment 1 will be described.

As shown in FIG. 4, in the compression mechanism of the present reference embodiment (20), the oil groove (80) is formed in the fixed scroll (30) but movable scroll (40). Specifically, the oil groove of this preferred embodiment (80) is formed in the movable side end plate portion of the movable scroll (40) (41). The oil groove (80) is a concave groove formed on the movable side thrust sliding surface (45) of the movable side end plate part (41) and has a ring shape surrounding the movable side wrap (42). Is formed. Further, in this preferred embodiment, the fixed side thrust sliding surface of the fixed scroll (30) (35), the end of the connection passage (86) is opened. The end of this connection passage (86) is formed wide so that it can continue to communicate with the oil groove (80) even if the movable scroll (40) moves.

In this reference embodiment, as in the above reference embodiment 1 , the bearing oil supply passage (70) is not in communication with the oil groove (80), and the oil reservoir (18) in the casing (15) and the oil groove (80) Refrigerating machine oil flows through the groove communication passage (85) only due to the pressure difference, and a part of the groove communication passage (85) is constituted by the capillary tube (87). Therefore, according to this preferred embodiment, the same effects as in the Reference Embodiment 1 is obtained.

<< Embodiment of the Invention >>
Describing the embodiments of the present invention. Here, the difference from the reference embodiment 1 will be described for the scroll compressor (10) of the present embodiment.

As shown in FIG. 5, in this embodiment, the configuration of the central cylindrical portion (56) of the lower bearing member (55) is different from that of the reference embodiment 1 . Specifically, the central cylindrical portion (56) is formed so as to extend from the upper end to the lower end of the auxiliary shaft portion (67) constituting the lower end portion of the drive shaft (60). Further, a concave portion is formed in the upper end portion of the central cylindrical portion (56), and a rolling bearing (54) is provided in the concave portion. The auxiliary bearing (67) of the drive shaft (60) is inserted through the rolling bearing (54). With this configuration, the central cylindrical portion (56) constitutes a secondary bearing that supports the secondary shaft portion (67).

  In the present embodiment, the groove communication passage (85) includes the first connection passage (81) formed in the fixed scroll (30) and the second connection passage (82) formed in the housing (25). ), A third connecting passage (83) formed in the lower bearing member (55), and a connecting pipe (84) connecting the second connecting passage (82) and the third connecting passage (83). It is constituted by.

  As shown in FIG. 6, the first connection passage (81) is formed in the outer peripheral portion (33) of the fixed scroll (30), and the inner vertical communication hole (up and down) extends vertically at the inner edge of the outer peripheral portion (33). 81a), a lateral communication hole (81b) extending radially in the outer peripheral part (33), and an outer vertical communication hole (81c) extending vertically in the outer edge part of the outer peripheral part (33).

  The inner vertical communication hole (81a) has an upper end opened at the upper surface of the fixed-side end plate portion (31), and a lower end opened at an oil groove (80) formed in the fixed-side thrust sliding surface (35). . A female screw (81d) is formed on the wall portion that forms the upper end of the inner vertical communication hole (81a). The inner vertical communication hole (81a) is provided with a rod-shaped member (89) described later, and the upper end portion of the inner vertical communication hole (81a) is closed by the head (89d) of the rod-shaped member (89).

  The horizontal communication hole (81b) extends radially outward from a position immediately below the female screw (81d) of the inner vertical communication hole (81a), and the outer end opens to the outer peripheral surface of the fixed scroll (30). The opening at the outer end of the horizontal communication hole (81b) is closed by a plug member.

  The outer vertical communication hole (81c) extends downward from a position slightly inward of the outer end of the horizontal communication hole (81b), and its lower end opens at the lower end surface of the fixed scroll (30).

  With such a configuration, the inner vertical communication hole (81a), the horizontal communication hole (81b), and the outer vertical communication hole (81c) communicate with each other in order to connect the oil groove (80) and the lower end surface of the fixed scroll (30). The connecting first connecting passage (81) is formed.

  The second connection passage (82) is formed to extend vertically in the outer peripheral portion of the housing (25). The upper end of the second connection passage (82) opens at the upper end surface of the housing (25), and corresponds to the outer longitudinal communication hole (81c) of the first connection passage (81). ). On the other hand, the lower end of the second connection passage (82) opens to the lower end surface of the housing (25). The second connection passage (82) is formed to have a slightly larger diameter than the outer vertical communication hole (81c) of the first connection passage (81), and the lower end portion is slightly smaller than the other portions. It is formed in a small diameter. An upper end portion (84a) of a connecting pipe (84), which will be described later, and an upper portion (91b) of a connecting pipe (91) are press-fitted into the small diameter portion. With such a configuration, the second connection passage (82) connects the first connection passage (81) and the connecting pipe (84).

  As shown in FIG. 7, the third connecting passage (83) is formed from an inner vertical communication hole (83a) extending vertically in the central cylindrical portion (56) of the lower bearing member (55) and the central cylindrical portion (56). It has a horizontal communication hole (83b) extending in the radial direction over the arm part (57) and an outer vertical communication hole (83c) extending vertically at the outer edge of the arm part (57).

  The inner vertical communication hole (83a) has an upper end connected to the recess and opens below the rolling bearing (54) provided in the recess, while the lower end is the lower end of the central cylindrical portion (56) located in the oil sump (18). Is open. The wall surface forming the upper end portion of the inner vertical communication hole (83a) is formed in the female screw (83d). The inner vertical communication hole (83a) is provided with a rod-shaped member (89) described later, and the upper end portion of the inner vertical communication hole (83a) is closed by the head (89d) of the rod-shaped member (89).

  The horizontal communication hole (83b) extends radially outward from a position immediately below the female screw (83d) that forms the upper end of the inner vertical communication hole (83a), and the outer end is the outer peripheral surface of the arm part (57). Is open. The opening at the outer end of the lateral communication hole (83b) is closed by a plug member. The outer vertical communication hole (83c) has an upper end that opens to the upper end surface of the arm portion (57), while a lower end that opens to the lower end surface of the arm portion (57), and slightly outside the outer end of the horizontal communication hole (83b). It communicates with the lateral communication hole (83b) at a position closer to the inside.

  The lower end (84b) of the connecting pipe (84) is inserted into the upper part of the outer vertical communication hole (83c), while the opening at the lower end is closed by a plug member. Further, the upper end portion of the outer vertical communication hole (83c) is formed in a large diameter portion that is larger in diameter than the middle main body portion. The large-diameter portion has an upper half formed larger in diameter than the lower half, an O-ring (92) is installed in the lower half, and a protrusion (93a) of the pressing member (93) is formed in the upper half. ) Is inserted.

  The pressing member (93) is configured by a metal plate-like piece in which an insertion hole (93b) through which the connecting pipe (84) is inserted and a bolt hole (93c) through which the bolt is inserted are formed. The lower end portion of the peripheral wall portion of the insertion hole (93b) of the pressing member (93) is formed as a protruding portion (93a) protruding downward from the other portions. The holding member (93) is a bolt inserted into the bolt hole (93c) in a state where the protruding portion (93a) is inserted into the large diameter portion of the outer vertical communication hole (83c) so as to hold the O-ring (92). Are fastened to the arm portion (57) of the lower bearing member (55). By inserting the connecting pipe (84) into the O-ring (92) pressed against the outer vertical communication hole (83c) by such a pressing member (93), the internal space of the casing (15) and the outer space The space between the vertical communication hole (83c) is sealed.

  With such a configuration, the inner vertical communication hole (83a), the horizontal communication hole (83b), and the outer vertical communication hole (83c) communicate with each other in order to connect the oil reservoir (18) and the communication pipe (84). 3 connecting passages (83) are formed.

  The connecting pipe (84) is constituted by a resin pipe formed of a resin material. As shown in FIG. 8, the connecting pipe (84) has an upper end portion (84a) formed with a larger diameter than the middle body portion, and a lower end portion (84b) formed with a smaller diameter than the body portion. Yes. A lower portion (91a) of the connecting pipe (91) formed of stainless steel is press-fitted into the upper end portion (84a) formed to have a large diameter.

  The connecting pipe (91) is formed such that the lower part (91a) below the axial center is smaller in diameter than the upper part (91b) above. Specifically, the connecting pipe (91) has an outer diameter of the lower portion (91a) slightly larger than an inner diameter of the upper end (84a) of the connecting pipe (84) and the upper end of the connecting pipe (84). The outer diameter of the upper portion (91b) is substantially equal to the outer diameter of the upper end portion (84a) of the connecting pipe (84), while the outer diameter of the upper portion (91b) is smaller than the outer diameter of the portion (84a).

  As shown in FIG. 6, the upper end (84a) of the connecting pipe (84) into which the lower part (91a) of the connecting pipe (91) is press-fitted is a small-diameter portion at the lower end of the second connecting passage (82). It is press-fitted into. Therefore, the upper end portion (84a) of the connecting pipe (84) and the upper portion (91b) of the connecting pipe (91) abut against the wall surface of the small diameter portion of the lower end portion of the second connecting passage (82), and the casing (15 ) And the second connecting passage (82) are sealed by these two members. Thereby, the 2nd connection channel | path (82) is connected with the inside of a connection pipe | tube (84) via the connection pipe | tube (91), without connecting with the internal space of a casing (15).

  On the other hand, as shown in FIG. 7, the lower end part (84b) of the connecting pipe (84) is inserted into the upper part of the outer vertical communication hole (83c) of the third connecting passage (83). Specifically, the lower end portion (84b) of the communication pipe (84) is inserted into the insertion hole (93b) of the pressing member (93) and the inside of the O-ring (92), and the tip is connected to the third connection passage (83 ) Of the outer vertical communication hole (83c) and the horizontal communication hole (83b). In this way, the connecting pipe (84) is inserted inside the O-ring (92) and inserted into the outer longitudinal communication hole (83c) of the third connecting passage (83), so that the third connecting passage (83 ) Communicates with the interior of the connecting pipe (84) without communicating with the internal space of the casing (15).

  As shown in enlarged views in FIG. 6 and FIG. 7, it is provided in each of the inner vertical communication hole (81 a) of the first connection passage (81) and the inner vertical communication hole (83 a) of the third connection passage (83). The rod-shaped member (89) has a main body part (89a), a small diameter part (89b), a screw part (89c), and a head part (89d) formed continuously from the distal end side to the proximal end side. is doing.

  The main body portion (89a) is formed of a cylindrical rod-like body, and a thin spiral groove (89e) having a width of about 0.5 to 1.0 mm is formed on the outer peripheral portion. By the main body portion (89a) having such a configuration, a spiral narrow passage is formed between each of the inner vertical communication holes (81a, 83a). The small-diameter portion (89b) is formed to have a smaller diameter than the inner vertical communication holes (81a, 83a), and forms an annular passage between the inner wall and the inner vertical communication holes (81a, 83a). In the annular passage, the inner ends of the lateral communication holes (81b, 83b) are opened. The threaded portion (89c) is constituted by a cylindrical rod-like body, and a male thread that is screwed into a female thread (81d, 83d) that forms the upper end of each inner vertical communication hole (81a, 83a) on the outer periphery. Is formed. The head (89d) is formed in a disk shape having a larger diameter than the inner vertical communication holes (81a, 83a).

  By the rod-like member (89) as described above, a spiral narrow passage is formed by the main body portion (89a) in each of the inner vertical communication holes (81a, 83a) provided with the rod-like member (89). As a result, the flow rate of the refrigeration oil flowing into the inner vertical communication holes (81a, 83a) is restricted in the spiral narrow passage formed on the outer peripheral side of the rod-like member (89). That is, the rod-like member (89) constitutes a throttle portion for limiting the flow rate of the refrigeration oil in the groove communication path (85).

In the present embodiment, the groove communication passage (85) constituted by the first to third connection passages (81 to 83) and the connecting pipe (84) is provided with an oil groove (80) in the casing (15). Only connected to the oil sump (18). Accordingly, in this embodiment as well, as in the first embodiment, the oil supply passage (77) formed in the drive shaft (60) is not in communication with the oil groove (80) formed in the fixed scroll (30). It is in a state. That is, the bearing oil supply passage (70) is disconnected from the oil groove (80), and the refrigerating machine oil is grooved only due to the pressure difference between the oil reservoir (18) in the casing (15) and the oil groove (80). Flows through the communication passage (85).

  Specifically, the refrigerating machine oil in the oil sump (81) is grooved in the order of the third connecting passage (83), the connecting pipe (84), the second connecting passage (82), and the first connecting passage (81). It flows through the communication passage (858) and is supplied to the oil groove (80). As a result, the oil groove (80) is filled with high-pressure refrigerating machine oil, and the refrigerating machine oil in the oil groove (80) is moved between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35 ) Is gradually discharged into the gap, and is used to lubricate these thrust sliding surfaces (35, 45).

  Thus, also in the present embodiment, the refrigerating machine oil is reliably supplied to the gap between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35). For this reason, even when the movable scroll (40) is strongly pressed against the fixed scroll (30), the frictional force generated on the movable thrust sliding surface (45) and the fixed thrust sliding surface (35) becomes excessive. There is nothing.

  Also in the present embodiment, the groove communication passage (85) is provided with a rod-like member (89) serving as a throttle portion for limiting the flow rate of the refrigerating machine oil. Therefore, also in the present embodiment, even when the movable scroll (40) is inclined to increase the clearance between the movable thrust sliding surface (45) and the fixed thrust sliding surface (35), the groove communication path (85) The flow rate of the refrigerating machine oil that has flowed into the pipe is limited in a spiral narrow passage formed on the outer peripheral side of the rod-like member (89).

Thus, also in this embodiment, even when the movable scroll (40) is tilted, the flow rate of the refrigerating machine oil flowing into the oil groove (80) from the groove communication path (85) is kept low, and the oil groove (80 ) Pressure is kept low. Therefore, even when the movable scroll (40) is tilted during the operation of the compression mechanism (20), the pressure acting on the thrust sliding surfaces (35, 45) is kept low, and the movable scroll (40) is fixed to the fixed scroll (30 The power to pull away from) will not be excessive. On the other hand, a pressing force for pressing the movable scroll (40) against the fixed scroll (30) acts on the movable scroll (40). For this reason, the movable scroll (40) tilted during the operation of the compression mechanism (20) receives this pressing force and quickly returns to its original posture. Therefore, the same effects as those of the first embodiment can be obtained by this embodiment.

  Further, according to the present embodiment, the freezing in the groove communication path (85) can be achieved by simply inserting the rod-shaped member (89) having the spiral groove (89e) formed in the outer peripheral portion into the groove communication path (85). A throttle portion that limits the flow rate of machine oil can be easily formed. Moreover, the passage sectional area of the groove communication passage (85) can be easily changed only by changing the sectional shape of the spiral groove (89e) on the outer peripheral portion of the rod-like member (89). That is, by configuring the throttle portion with the rod-shaped member (89), the degree of freedom in design is improved and the design can be easily changed.

  In addition, when the throttle part that restricts the flow rate of the refrigerating machine oil in the groove communication path (85) is configured by the rod-like member (89) having the spiral groove (89e) formed on the outer peripheral part as described above, a sufficient throttle effect In order to obtain this, it is necessary to lengthen the length of the narrow passage formed by the spiral groove (89e) to some extent. However, if the length of the rod-shaped member (89) is increased to increase the length of the narrow passage, a long space is required to install the rod-shaped member (89), and there is a risk that the installation work may be time-consuming.

  On the other hand, in this embodiment, since the rod-like member (89) constituting the throttle portion is provided at a plurality of locations in the groove communication path (85), the length of one rod-like member (89) is short. Can also increase the total length of the narrow passage. Therefore, the flow rate of the lubricating oil in the groove communication path (85) can be sufficiently limited. In other words, the length of each rod-shaped member (89) can be shortened by providing the rod-shaped member (89) at a plurality of locations in the groove communication path (85). Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

  Furthermore, in the present embodiment, the third connection passage (83) and the second connection passage (83), which are communication holes forming part of the groove communication passage (85) in both the lower bearing member (55) and the fixed scroll (30), are provided. Since one connecting passage (81) is formed and a rod-like member (89) constituting the throttle portion is provided for each, one rod-like member (89) and a communication hole (the third connecting passage (83) and the first Even if the length of the one connecting passage (81)) is short, the total length of the narrow passage can be increased. Therefore, the flow rate of the refrigerating machine oil in the groove communication path (85) can be sufficiently limited. In other words, communication holes (third connection passage (83) and first connection passage (81)) are formed in both the lower bearing member (55) and the fixed scroll (30), and the rod-like members (89 ) Can be used to shorten the length of each rod-like member (89). Therefore, it is not necessary to secure a long space for installing the rod-shaped member (89), and the rod-shaped member (89) can be easily installed.

  In the present embodiment, the connecting pipe (84) that forms a part of the groove communication path (85) is provided between the casing (15) and the electric motor (50). When the connecting pipe (84) provided on the side of the electric motor (50) is a metal pipe, it is necessary to separate the electric motor (50) from the electric motor (50) by a distance that ensures insulation. The diameter of the casing (15) must be increased by the distance of However, in this embodiment, the connecting pipe (84) provided on the side of the electric motor (50) is constituted by a resin pipe formed of a resin material. Therefore, insulation can be ensured without providing the connecting pipe (84) away from the electric motor (50). Therefore, the diameter of the casing (15) can be reduced. That is, it is possible to reduce the size of the scroll compressor.

  Note that the connecting pipe (84) may not be formed entirely of a resin material as described above, but may be formed of a metal pipe covering only the outer peripheral surface of the metal pipe.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a scroll compressor that compresses a refrigerant or the like.

10 Scroll compressor
15 casing
18 Oil sump
20 Compression mechanism
30 Fixed scroll
35 Fixed-side thrust sliding surface
40 movable scroll
41 Movable end panel (end panel)
45 Movable thrust sliding surface
60 Drive shaft
70 Oil supply passage (oil supply passage for bearings)
75 Oil pump
80 Oil groove
85 Groove communication passage
87 Capillary tube (throttle part)

Claims (8)

A casing (15), a compression mechanism (20) having a fixed scroll (30) and a movable scroll (40) housed in the casing (15), and the movable scroll (40) housed in the casing (15); A drive shaft (60) engaged with the
The compression mechanism (20) is configured to discharge a compressed fluid into the casing (15) and generate a pressing force for pressing the movable scroll (40) against the fixed scroll (30). A scroll compressor,
The end plate portion (41) of the movable scroll (40) and the fixed scroll (30) are formed with a movable thrust sliding surface (45) and a fixed thrust sliding surface (35) that are in sliding contact with each other,
An oil groove (80) into which lubricating oil flows is formed in the movable thrust sliding surface (45) or the fixed thrust sliding surface (35),
The oil groove (80) is not in communication, and the lubricating oil in the oil reservoir (18) in the casing (15) is supplied to the bearing of the drive shaft (60) provided in the compression mechanism (20). A bearing oil supply passage (70);
A scroll compressor comprising a groove communication path (85) for connecting the oil groove (80) to an oil reservoir (18) in the casing (15). In claim 1,
The bearing oil supply passage (70) is provided with an oil supply pump (75) that is driven by the drive shaft (60) and sucks and discharges lubricating oil from an oil reservoir (18) in the casing (15).
The groove communication path (85) is configured such that lubricating oil flows only by a pressure difference between the oil reservoir (18) in the casing (15) and the oil groove (80). Scroll compressor. In claim 2,
A scroll compressor characterized in that the groove communication passage (85) is provided with a throttle for limiting the flow rate of the lubricating oil. In claim 3,
The throttle portion is formed by a rod-like member (89) that is inserted into the groove communication passage (85) and has a spiral groove (89e) for flowing lubricating oil on the outer peripheral portion. Scroll compressor. In claim 4,
The scroll compressor, wherein the bar-shaped member (89) is provided at a plurality of locations of the groove communication path (85). In claim 5,
A bearing (55) provided separately from the compression mechanism (20) and rotatably supporting the drive shaft (60);
The bearing (55) and the fixed scroll (30) are respectively formed with communication holes (83, 81) forming a part of the groove communication path (85).
A scroll compressor characterized in that the rod-like member (89) is provided in each of the communication holes (83, 81). In any one of Claims 1 thru | or 6,
An electric motor (50) for rotationally driving the drive shaft (60);
A connecting pipe (84) provided between the casing (15) and the electric motor (50) and forming a part of the groove communication path (85);
The scroll compressor characterized in that the connecting pipe (84) is constituted by a resin pipe formed of a resin material or a metal pipe whose outer peripheral surface is covered with a resin material. In any one of Claims 1 thru | or 7,
The scroll is characterized in that the lubricating oil inlet (88) of the groove communication passage (85) is formed above the lubricating oil suction port (76) of the bearing oil supply passage (70). Compressor.

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