JPH05187369A - Scroll compressor - Google Patents

Abstract

PURPOSE:To provide a scroll compressor excellent in low vibration and low noise characteristics and durability. CONSTITUTION:An oil feed passage passing in sequence a lubricating oil feed source on which discharge gas pressure is exerted, a back pressure chamber 20 of turning scroll 14, and a suction chamber 22, is provided, and an oil feed passage control device is arranged between the back pressure chamber 20 and suction chamber 22 on the way of the oil feed passage. This oil feed passage control device is provided with an opening degree adjusting function for continuously changing an opening degree of throttle passage in order to control a pressure difference between the back pressure chamber 20 and suction chamber 22 within a predetermined range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly to a back pressure control for an orbiting scroll.

[0002]

2. Description of the Related Art In recent years, scroll compressors, which have been put into practical use with the development of machine tools and have been attracting attention as compressors having low vibration and low noise characteristics, have been disclosed in, for example, Japanese Patent Laid-Open No. 59-59.
As also disclosed in Japanese Patent No. 49386, the suction chamber is provided at the outer peripheral portion and the discharge port is provided at the center of the vortex winding, and since the flow of the compressed fluid is in one direction, the fluid resistance during high-speed operation is small and the compression efficiency is high. High is generally well known.
Further, a compressor having a high-pressure gas closed shell structure of this type has a structure shown in FIG. 5 as known from Japanese Patent Laid-Open No. 59-49386 or a structure shown in FIG. 6 as known from Japanese Laid-Open Patent No. 55-148994. The structure shown, or the above-mentioned JP-A-55
A configuration of JP-A-57-68579, in which the compressor of JP-A-148994 is turned upside down, is proposed, and the thrust force in the axial direction is reduced by appropriately setting the back pressure chamber. Lubrication of each sliding portion was configured as follows. That is, in FIG. 5, the fixed scroll wrap 123 is fixed to the end plate 121 attached to the main body frame 102 supporting the drive shaft 105, the orbiting scroll wrap 116 is fixed to the lap support disk 115, and the wrap support disk 115 is End plate 121 and body frame 10
It is arranged in a back pressure chamber 120 in a loose state with a small gap between the two, and is rotatably supported via an Oldham ring 118 having a rotation preventing function and a back pressure chamber partitioning function, and further, an end portion. Further, the motor 110 for driving and the drive shaft 105 having an eccentric portion make a turning motion. Then, the sucked and compressed gas is discharged into the closed shell 101. Lubricating oil separated from the discharge gas is collected in an oil sump at the bottom of the closed shell 101, is opened in the lower end of the drive shaft 105 and is provided in an eccentric oil hole 106, and a minute gap in the bearing that supports the drive shaft 105. While being gradually depressurized, the gas is introduced into the back pressure chamber 120 in a high pressure state by utilizing the centrifugal pump action. Further, the lubricating oil that has been reduced to an intermediate pressure between the discharge pressure and the suction pressure through the minute gap in the sliding portion of the Oldham ring 118 is
The sliding portion is lubricated in the process of flowing into the suction chamber 122 through the fine balance passage 126 provided in the end plate 121. Further, in FIG. 6, the back pressure chamber 220 is neither partitioned by pressure by the Oldham ring 218 nor communicated with the suction chamber 222, but a fine hole balance passage 226 provided in the lap support disk 215 of the orbiting scroll. Is communicated with the compression chamber 240 at an appropriate position by means of which the balance passage 226 is opened and closed by the lap support disk 215 making a pivotal movement, so that the back pressure chamber 220 and the compression chamber 24 are opened.
0 constitutes an intermittent oil supply passage, and the sliding portion of the back pressure chamber 220 and each bearing portion of the drive shaft 205 are different from the oil reservoir 209 at the bottom of the closed shell 201 filled with the discharge gas. The drive shaft 205 is communicated with an oil hole 206 and a minute gap of a bearing that supports the drive shaft 205, and is communicated with a centrifugal pump by differential pressure.

[0003]

However, in the configuration of the oil supply passage in which the opening of the throttle passage from the inside of the back pressure chamber 120 to the suction chamber 122 as shown in FIG. 5 is fixed, the compressor operating speed and the high and low pressure side are increased. The temperature of the lubricating oil flowing from the back pressure chamber 120 into the suction chamber 122 varies depending on the load conditions of the above, and the viscosity of the lubricating oil changes accordingly, and the lubricating oil inflow chamber from the back pressure chamber 120 to the suction chamber 122 varies. As a result, even if the pressure in the back pressure chamber 120 is appropriately set under a specific operating condition, if the compressor operating condition is different, the pressure in the back pressure chamber 120 abnormally rises or falls. As a result, the orbiting scroll 114 is excessively pressed by the fixed scroll 134, or the orbiting scroll 114 is separated from the fixed scroll 134, resulting in abnormal wear of the sliding portion and power loss.
This causes an abnormal decrease in compression efficiency and causes an excess or deficiency in the amount of lubricating oil flowing into the suction chamber 122, resulting in a decrease in compression efficiency due to excessive inflow of lubricating oil and a decrease in the oil film sealing effect in the compression chamber gap due to insufficient lubricating oil. There was a problem of causing an abnormal temperature rise. In the case of FIG. 6 also, the back pressure chamber 220 and the compression chamber 2
Since the opening degree of the balance passage 226 communicating with 40 is fixed, there is a problem similar to the above. As measures for preventing the pressure in the back pressure chamber from rising abnormally, (1) JP-A-57-76291 and (2) JP-A-58-1605.
83, JP-A-58-176489, JP-A-58-183887, (3) JP-A-56-165.
The configuration of Japanese Patent No. 787 has been proposed. That is,
In (1), the back pressure chamber and the suction side are communicated with each other via a control valve, and when the pressure in the back pressure chamber rises abnormally, the control valve is opened to allow the fluid in the back pressure chamber to flow out to the suction side. This is a configuration for controlling the pressure in the pressure chamber. Further, (2) has a configuration in which when the back pressure chamber pressure becomes higher than the discharge pressure, the control valve is opened to communicate with the suction side or the discharge gas pressure side to control the back pressure chamber pressure. Further, (3) is a configuration in which while the oil on the discharge pressure side is differentially supplied to the sliding surface related to the back pressure chamber, the discharge gas is decompressed and guided to the back pressure chamber to maintain the back pressure chamber at an intermediate pressure. Is. However, in the configuration of (1), it may flow into the back pressure chamber,
Since only the flow rate of gas flowing out from the back pressure chamber is controlled, no consideration has been given to the oil supply to the back pressure chamber, and there has been a problem that the wear of the members related to the back pressure chamber is remarkable. Further, in the configuration of (2), the back pressure chamber pressure is only controlled to be lower than the discharge pressure, and the orbiting scroll is pressed to the fixed scroll side too much, resulting in sliding between the orbiting scroll and the fixed scroll. There was a problem that the wear of the surface was fast and the friction loss was large. Further, in the configuration of (3), since the oil supply passage to the back pressure chamber and the gas introduction passage are separately configured, oil is difficult to disperse in the entire back pressure chamber, and oil shortage occurs partially and seizure occurs. .. Further, since the pressure of the back pressure chamber is controlled by adjusting the pressure of the discharge gas having a low viscosity, there is a large variation in the pressure reduction adjustment, which makes it difficult to set the pressure of the back pressure chamber. Also, (1)
To (3) are combined, that is, differential pressure oil is supplied to the back pressure chamber from an oil reservoir under the action of the discharge gas pressure through an appropriate throttle oil supply passage, and between the back pressure chamber and the suction chamber (or compression chamber). It is conceivable that the back pressure chamber is restored to the normal pressure by opening the control valve only when the back pressure chamber pressure rises abnormally by communicating the above through the control valve as in (1). By repeatedly opening and closing between the suction chamber (or the compression chamber) and the suction chamber (or compression chamber), the compression load and back pressure chamber pressure change abruptly, fluctuations in load torque, abnormal noise due to orbiting scroll flapping, and back pressure chamber There is an important problem that the original low vibration and low noise characteristics of the scroll compressor are impaired by the gas blow-through noise generated when the gas blows into the suction chamber (or the compression chamber). On the other hand, as a measure for preventing the pressure in the back pressure chamber from being abnormally lowered, the configuration of Japanese Patent Application Laid-Open No. 58-160580 has been proposed. This structure is provided with a passage that connects the back pressure chamber and the discharge gas passage side, and when the back pressure chamber pressure becomes lower than the set pressure, the control valve in the middle of the passage is opened to discharge the high pressure gas from the discharge gas passage side. Is introduced into the back pressure chamber so that the back pressure chamber pressure is controlled not to become too low. However, even in this configuration, as in the case of Japanese Patent Laid-Open No. 57-76291, no consideration is given to always ensuring the amount of oil supplied to the back pressure chamber, and there is the same problem as described above. Therefore, the present invention controls the back pressure chamber pressure by continuously changing the opening degree of the throttle passage between the back pressure chamber and the suction chamber (or the compression chamber) in the middle of the fuel supply passage, thereby reducing the vibration and noise. It is intended to provide a scroll compressor having excellent characteristics and durability.

[0004]

In order to solve the above problems, a scroll compressor according to the present invention has a lubricating oil supply source on which discharge gas pressure acts, a back pressure chamber of an orbiting scroll, and a suction chamber (or compression chamber). An oil supply passage that sequentially passes is provided, and an oil supply passage control device is arranged between the back pressure chamber and the suction chamber (or compression chamber) in the middle of the oil supply passage. In order to control the pressure difference between the chamber and the chamber within a set range, it is provided with an opening adjustment function for continuously changing the opening of the throttle passage.

[0005]

With the above structure, the discharge pressure is low for a while immediately after the cold start of the compressor, so that the pressure of the lubricating oil flowing into the back pressure chamber from the lubricating oil supply source is also low. The opening of the throttle passage is small, and the amount of lubricating oil flowing from the back pressure chamber to the suction chamber (or compression chamber) is reduced. This accelerates the pressure rise in the back pressure chamber, stabilizes the orbiting scroll early by setting the early back pressure, prevents the orbiting scroll from flapping due to insufficient back pressure, and produces abnormal noise and abnormal wear of sliding parts. Prevent. In addition, as the discharge gas rises with the lapse of time after the start of the engine and the pressure of the lubricating oil flowing from the lubricating oil source to the back pressure chamber rises, the oil supply passage control device gradually widens the opening of the throttle passage to increase the back pressure. The amount of lubricating oil flowing from the pressure chamber to the suction chamber (or compression chamber) is increased, the back pressure chamber pressure is controlled within the set range, and the stable proper pressing force of the orbiting scroll with respect to the fixed scroll is maintained, and the load fluctuation Continue low quiet operation.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A scroll compressor according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view of a scroll refrigerant compressor according to an embodiment of the present invention,
FIG. 2 is a detailed explanatory diagram of the portion A in FIG. In FIG. 1, 1 is a closed shell, 2 is a closed shell 1
The main body frame is press-fitted into the main body frame 3, 3 and 4 are bearings provided in the central portion of the main body frame 2, and 5 is an oil hole 6 supported by the bearings 3 and 4 and an oil hole 6 at a position facing the bearing 4. An eccentric shaft portion 8 is provided at the upper end of the drive shaft, which communicates with the oil hole 7, and the lower end extends into the oil reservoir 9 at the bottom of the closed shell 1 and is immersed therein. Reference numeral 10 denotes a motor, a rotor 11 of which is fixed to the drive shaft 5 and a stator 12 of which is fixed to the hermetic shell 1 by press fitting. The wrap support disk 15 of the orbiting scroll 14 which is connected to the eccentric shaft portion 8 and has the bearing portion 13 at the center thereof is integrally formed with the orbiting scroll wrap 16 which is upright on the upper surface thereof, and the lower surface thereof is the upper end of the main body frame 2. It is supported by a thrust bearing seat 17 protruding into the opening hole. The orbiting scroll wrap 16 has a spiral shape in a plan view,
The vertical cross section is rectangular and adjacent orbiting scroll wraps 16 are parallel to each other. The rotation-preventing Oldham ring 18 is provided with parallel key-shaped key portions orthogonal to each other on both sides of a flat ring, and is provided between the lap support disk 15 and the thrust bearing seat 17. The key portion on the upper surface side of the Oldham ring 18 is fitted in the key groove (not shown) provided on the back surface of the lap support disk 15, and the key portion on the lower surface side is fitted in the key groove 19 provided in the thrust bearing seat 17. The rotation of the drive shaft 5 causes the bearing portion 13 of the wrap support disk 15 to make a circular motion around the axis of the drive shaft 5, and the orbiting scroll wrap 16 makes an orbiting motion. Also,
A fixed scroll 34 is formed as a back pressure chamber 20 of the lap support disk 15 by closing an upper end opening hole in the upper end surface of the main body frame 2.
The end plate 21 is attached together with the thrust bearing seat 17 so as to sandwich the orbiting scroll 14 with a minute gap. Back pressure chamber 2
0 is divided by a lap support disk 15 and is divided into a back pressure chamber 20a on the outer peripheral surface thereof and a back pressure chamber 20b on the back surface side. An annular suction chamber 22 is provided inside the end plate 21, and the inside of the closed shell 1 is discharged at the center of the spiral of a fixed scroll wrap 23 that is parallel to the orbiting scroll 16 and has the same shape. The discharge port 25 is provided to open the sliding surface with the lap support disk 15 and connect the suction passage 22 and the back pressure chamber 20a to each other through a balance passage 26 of a small hole, the back pressure chamber 20a and the back pressure chamber 20b. A fine hole balance passage 27 communicating with each other is provided in the end plate 21 and the thrust bearing seat 17, and is arranged so as to communicate with each other only when the lap support disk 15 is in a predetermined swing angle range (the compression chamber is in the suction stroke). As shown in FIG. 2, the case 40 is press-fitted into the end plate 21 in the middle of the balance passage 26 so as to sandwich the openings at both ends of the balance passage 26. The flow side steel balls 41, the oil supply passage control device coil spring 42 is mounted on the downstream side 43
The coil spring 42 moves the steel ball 41 against the back pressure acting on the steel ball 41 on the basis of the pressure difference between the back pressure chamber 20 and the suction chamber 22 to adjust the opening degree of the balance passage 26. The steel ball 41 is constantly urged so as to be continuously changed. In addition, the annular suction chamber 22 has a closed shell 1 from the side.
Is connected to a suction pipe 28, and the upper surface of the closed shell 1 is provided with a discharge pipe 2 opening toward the inner side surface of the closed shell 1.
9 is connected. A groove 30 is provided on the outer surface of the body frame 2 press-fitted and fixed to the closed shell 1.
Reference numeral 0 connects the discharge space 24 on the end plate 21 side of the closed shell 1 to the motor 10 side. The operation of the scroll refrigerant compressor configured as described above will be described below with reference to FIGS. 1 and 2. First, FIG. 1 is a vertical sectional view of a scroll refrigerant compressor, and FIG. 2 is a balance passage 2 in FIG.
6 is a detailed view of a portion A in the vicinity of 6, wherein the orbiting scroll 14 orbits when the rotor 11 is rotated by the motor 10 and the drive shaft 5 is rotationally driven, and the refrigerant gas passes through the suction pipe 28 and the suction chamber 22. The refrigerant gas is drawn into the compression chamber formed between the orbiting scroll wrap 16 and the fixed scroll wrap 23, is compressed by the orbiting motion of the orbiting scroll wrap 16, and is discharged from the discharge port 25 to the discharge space 24. A part of the lubricating oil discharged and contained in the refrigerant gas is separated from the refrigerant gas by its own weight and the like, and is collected in the bottom oil sump 9 through the groove 30 between the closed shell 1 and the main body frame 2, The remaining lubricating oil is discharged to the external refrigeration cycle through the discharge pipe 29 together with the discharge refrigerant gas. On the other hand, the differential pressure oil supply from the high pressure side oil reservoir 9 to the low pressure side suction chamber 22 via the back pressure chamber 20 formed by being separated from the discharge space 24 by the end plate 21 of the fixed scroll 34 and the main body frame 2 is performed. This is done as follows. That is, the back pressure chamber 20 is kept for a while after the cold start of the compressor.
And the pressure difference between the suction chamber 22 and the balance passage 2 is small.
The opening degree of 6 is narrowed to the minimum state. The low-viscosity lubricating oil in the oil reservoir 9 at the bottom of the closed shell 1 filled with the discharged refrigerant gas is provided with the oil holes 6 and 7 provided in the drive shaft 5 and the bearings 3 and 4 supporting the drive shaft 5 and the eccentric shaft portion. The pressure is gradually reduced by passing through the minute gap of the bearing 13 of No. 8 and is supplied to the back pressure chamber 20b in a state of an intermediate pressure between the suction chamber force and the discharge pressure. Further, the lubricating oil is the lap support disk 15 of the orbiting scroll 14.
Oil is intermittently supplied to the back pressure chamber 20a through the balance passage 27 having a small hole which is opened and closed intermittently by the turning motion of the. Back pressure chamber 2
As the pressure of 0a increases, the opening degree of the balance passage 26 gradually expands, and the lubricating oil in the back pressure chamber 20a is intermittently supplied to the suction chamber 22 little by little, and is compressed and discharged again together with the suction refrigerant gas. The discharge pressure rises with the lapse of time after the start of the compressor, the amount of lubricating oil flowing from the oil reservoir 9 into the back pressure chamber 20 via the bearings 3, 4 and the bearing portion 13 increases, and the pressure in the back pressure chamber 20 also increases. To rise. In order to control the pressure difference between the back pressure chamber 20 and the suction chamber 22 within a set range, the oil supply passage control device gradually expands the opening of the throttle passage, and the lubricating oil flowing from the oil reservoir 9 into the suction chamber 22 is reached. The amount gradually increases. According to this differential pressure oil supply system, the pressure of the back pressure chamber 20 on the back surface of the lap support disk 15 can be freely set from the state close to the discharge pressure to the state close to the suction pressure by adjusting the passage resistance of the oil supply passage. The load difference between the gas pressure load acting on the back surface of the support disk 15 and the gas pressure load in the compression chamber can be freely adjusted, so that the lap support disk 15 can be pressed toward the end plate 21 or separated from the end plate 21. It can also be pressed against the thrust bearing seat 17 side. In the present embodiment, the lap support disk 15 in the case where the viscosity of the lubricating oil is low, such as during steady operation, acts so that the thrust force acts on the end plate 21 side, and in the case where the viscosity of the lubricating oil is high, such as immediately after cold start, Support disk 1
5 has a function of an oil supply passage control device in which the passage resistance of the balance passage 26 is adjusted so that the thrust force acts on the thrust bearing seat 17 side. In addition, this scroll refrigerant compressor is incorporated into a heat pump type refrigeration cycle, and immediately after switching from the heating operation refrigerant cycle to the defrosting operation refrigeration cycle, the discharge chamber pressure becomes a low pressure state, and the suction chamber pressure becomes a high pressure state. Gas from the suction chamber 22 to the back pressure chamber 2
0 tries to flow back to 0 through the balance passages 27, 27, but the steel ball 41 provided in the balance passage 26 closes the passage.
Refrigerant gas is prevented from flowing back into the oil reservoir 9 via the back pressure chamber 20, and the outflow of lubricating oil from the back pressure chamber 20 and the bearing sliding surface and seizure of the sliding surface are prevented. In this embodiment, the balance passage 26
Although the downstream opening hole is communicated with the end portion of the coil spring 42, it may be communicated with the vicinity of the central portion of the coil spring 42 or the steel ball 41 side as shown in FIG. Further, in the above embodiment, the suction chamber is located on the downstream side of the oil supply passage of the back pressure chamber 20, but as in the case of FIG.
The downstream side of the oil supply passage may be used as the compression chamber during the compression stroke,
An oil supply passage control device similar to that of FIG. 2 may be provided in the oil supply passage. The oil supply passage control device in this oil supply passage configuration also has a check valve function described below. That is, immediately after the compressor is started when the compressor is cold, the pressure of the discharge chamber communicating with the compressor external piping system is low, and the amount of lubricating oil flowing from the oil reservoir 9 into the back pressure chamber 20 is small. Back pressure chamber 2
It may be intermittently lower than the pressure of the compression chamber communicating with zero. For this reason, the refrigerant gas in the middle of compression tends to flow into the back pressure chamber 20, but the check valve action of the oil supply passage control device causes the lubricating oil accompanying the blowout of the refrigerant gas in the oil supply passage from the back pressure chamber 20 to the oil reservoir 9. Prevents outflow and seizure of sliding parts. In addition, instantaneous abnormal pressure rise in the compression chamber (liquid compression phenomenon) that occurs due to compression of the refrigerant liquid and a large amount of lubricating oil during compression.
It also prevents the refrigerant gas from flowing back to the back pressure chamber 20. As a result, an increase in pressure in the back pressure chamber 20 and an increase in back pressure biasing force on the orbiting scroll 14 are prevented, and the orbiting scroll 14 is prevented.
Can be separated from the fixed scroll 34 in the axial direction, and the pressure in the compression chamber can be drastically reduced to perform an overload reducing action. As described above, according to the above-described embodiment, the oil sump 9 on which the discharge gas pressure acts, the oil holes 6 and 7 provided in the drive shaft 5, the bearings 3 and 4 supporting the drive shaft 5, and the eccentric shaft portion 8 are formed. Bearing part 13
Of the back pressure chamber of the orbiting scroll 14 (back pressure chamber 20
b, the back pressure chamber 20a), and the suction chamber 22 are provided in sequence, and the back pressure chamber 20 and the suction chamber 22 are provided in the middle of the lubrication passage.
Between the oil passage control valve device 4 including a valve body of a steel ball 41 and a coil spring 42 for urging the valve body toward the upstream side in a balance passage 26 having a narrow hole portion provided in the end plate 21 between
3, the oil supply passage control valve device 43 continuously changes the opening degree of the upstream passage of the balance passage 26 so as to control the pressure difference between the back pressure chamber 20 and the suction chamber 22 within a set range. Since the opening adjustment mechanism that can be operated is provided, the discharge pressure is low for a while immediately after the compressor is started when the compressor is cold, and the oil sump 9
Even if the pressure of the lubricating oil flowing from the back pressure chamber 20 to the back pressure chamber 20 is low, the opening of the throttle passage of the oil supply passage control device 43 is small, so that the amount of lubricating oil flowing from the back pressure chamber 20 to the suction chamber 22 is minimized, thereby reducing the back pressure. It is possible to secure the lubricating oil in the pressure chamber 20 and accelerate the pressure rise. As a result, the thrust pressure acting on the orbiting scroll 14 and the thrust bearing seat 17 becomes excessive due to the high suction pressure at the initial stage of startup, and the thrust pressure seat 17 reduces the thrust load. It is possible to prevent deterioration of durability. Back pressure chamber 2
It is possible to prevent the fluttering of the orbiting scroll 14 from tilting or moving in the axial direction due to unstable back pressure, and prevent abnormal noise and durability of the sliding portion. In addition, the discharge pressure increases and the suction pressure decreases with the lapse of time after the start, and accordingly, after the back pressure chamber 20 reaches the set pressure, the amount of lubricating oil discharged from the back pressure chamber 20 to the suction chamber 22. Is controlled continuously, even if the discharge pressure rises to an abnormal pressure, the back pressure can be appropriately tracked accordingly, and fluctuations in compression load and fluctuations in back pressure can be reduced and stable compressor operation can be continued.

[0007]

As described above, according to the present invention, the lubricating oil supply source, the back pressure chamber, and the suction chamber (or the compression chamber), which are subjected to the discharge gas pressure, are sequentially provided, and the back pressure in the middle of the oil supply passage is provided. The oil supply passage control device is arranged between the suction chamber (or the compression chamber) and the suction chamber, and the oil supply passage control device controls the pressure difference between the back pressure chamber and the suction chamber (or the compression chamber) within the set range. Therefore, by providing an opening degree adjusting mechanism that continuously changes the opening degree of the throttle passage, the discharge pressure immediately after the compressor is started cold is low, and the lubricating oil that flows into the back pressure chamber 20 from the lubricating oil source is provided. Even when the oil pressure is relatively low, the opening of the throttle passage of the oil supply passage control device is small, so the amount of lubricating oil flowing out from the back pressure chamber to the suction chamber can be reduced, which allows the back pressure chamber to be filled with lubricating oil You can accelerate the rise. As a result, the pressure setting rise of the back pressure chamber is accelerated, and flapping of the orbiting scroll with respect to the fixed scroll and the drive shaft due to unstable back pressure, axial movement, etc. is prevented by the oil film straining action, and the sliding part is prevented. It is possible to improve the durability by preventing abnormal noise from being generated and abrasion. Also, after the discharge pressure rises and the differential pressure between the back pressure chamber and the suction chamber (or compression chamber) reaches the set range following the rise, the back pressure chamber moves to the suction chamber (or compression chamber). Since the amount of lubricating oil to be discharged is controlled continuously, there is no intermittent discharge noise of gas or lubricating oil, and even if the discharge pressure rises abnormally, the back pressure chamber pressure is continuously adjusted to an appropriate range by following it. By controlling, it is possible to reduce sudden changes in compression load and back pressure and to achieve a number of excellent effects that can realize low vibration and low noise operation.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a scroll refrigerant compressor according to a first embodiment of the present invention.

FIG. 2 is a sectional view of part A in FIG.

FIG. 3 is a partial cross-sectional view of a scroll refrigerant compressor showing another embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of a scroll refrigerant compressor showing different embodiments of the present invention.

FIG. 5 is a vertical cross-sectional view of different conventional scroll compressors.

FIG. 6 is a vertical cross-sectional view of different conventional scroll compressors.

[Explanation of symbols] 1 closed shell 2 main body frame 5 drive shaft 10 motor 14 orbiting scroll 15 wrap support disk 16 orbiting scroll wrap 20 back pressure chamber 21 end plate 22 suction chamber 23 fixed scroll wrap 25 discharge port 26, 27 balance passage 34 fixed Scroll 41 Steel ball 42 Coil spring 43 Oil supply passage control device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location F04C 29/02 321 A 6907-3H 29/06 D 6907-3H

Claims (1)

[Claims] 1. A fixed scroll wrap on a lap support disk which forms a part of an orbiting scroll is engaged with a fixed scroll wrap which is a spiral scroll formed on one surface of an end plate which forms a part of the fixed scroll. A suction chamber is formed on the outside of the wrap, and the wrap support disk is formed between the body frame supporting the drive shaft and the end plate and communicates with a lubricating oil supply source outside the body frame. Of the compression chamber formed between the fixed scroll wrap and the orbiting scroll by being rotatably supported by the lap support disk through a rotation preventing mechanism of the wrap support disk. Is used to form a scroll-type compression mechanism, and the lubricating oil supply source, the back pressure chamber, and the suction chamber, which act on the discharge pressure, are formed. Is provided with an oil supply passage sequentially passing through the compression chamber, and an oil supply passage control device is provided between the back pressure chamber and the suction chamber or the compression chamber or the back pressure chamber and the lubricating oil supply source in the middle of the oil supply passage. The refueling passage control device is arranged to continuously change the opening of the throttle passage so as to control the pressure difference between the back pressure chamber and the suction chamber or the compression chamber within a set range. Scroll compressor with degree adjustment function.