WO2021255881A1 - Scroll compressor and refrigeration cycle device - Google Patents

Abstract

Provided is a scroll compressor, etc., having high performance and reliability. The scroll compressor comprises a closed container, a fixed scroll (22), an orbiting scroll (23), a frame (21), an electric motor, and a shaft (3). Furthermore, the scroll compressor comprises a main bearing (11) installed in a shaft insertion hole (hf), an orbiting bearing (12) installed on an orbiting shaft (23c), a slide bush (13) installed in an eccentric hole (he) on the radially outer side of the orbiting bearing (12), and a ring (14) that closes an annular gap (g1) between an upper-end part (3b) of the shaft (3) and the slide bush (13) from above. Axial-direction installation areas (Q1, Q2) of the main bearing (11) and the orbiting bearing (12) overlap at least partially.

Description

Scroll compressor and refrigeration cycle device

The present invention relates to a scroll compressor or the like.

For example, the technique described in Patent Document 1 is known as a technique for improving the sealing property between the fixed scroll and the swivel scroll (swing scroll) of the scroll compressor. That is, Patent Document 1 describes that the swing bearing is slidably attached in a plane perpendicular to the axis of the crank shaft.

Japanese Unexamined Patent Publication No. 59-1207994

In the scroll compressor described in Patent Document 1, a long hole-shaped bearing fitting hole is provided at the upper end of the crank shaft, and the swing bearing is slid in a predetermined manner inside the bearing fitting hole. A swing scroll shaft is inserted on the inner peripheral side of the swing bearing and slides as a shaft with the bearing, so that a severe sliding state is likely to occur. Here, there is a space between the inner peripheral side of the long hole-shaped bearing fitting hole and the outer peripheral side of the oscillating bearing in the sliding direction of the oscillating bearing, and lubricating oil is easily supplied. Since there is almost no gap between the inner peripheral side of the oscillating bearing and the outer peripheral side of the oscillating scroll shaft, which are prone to severe sliding conditions, and the flow path resistance is large, it is difficult to supply lubricating oil.

Therefore, in the technique described in Patent Document 1, it is difficult to supply lubricating oil to the sliding portion with the swing scroll shaft, which tends to cause a severe sliding state in the swing bearing, and the performance and reliability of the scroll compressor are further improved. There is room to increase.

Therefore, it is an object of the present invention to provide a scroll compressor or the like having high performance and reliability.

In order to solve the above-mentioned problems, the present invention has a closed container, a fixed scroll having a spiral fixed wrap and fixed inside the closed container, and a spiral shape forming a compression chamber together with the fixed wrap. It has a swivel scroll having a swivel lap, a frame supporting the swivel scroll, an electric motor having a stator and a rotor, and a through hole for guiding lubricating oil, and is integrally with the rotor. A rotating shaft is provided, the upper end portion of the shaft is provided with an eccentric hole fitted to the swivel shaft, and the frame is provided with a shaft insertion hole through which the upper end portion of the shaft is inserted. A first bearing installed in the shaft insertion hole or installed at the upper end portion of the shaft, a second bearing installed on the swivel shaft, and a radial outer side of the second bearing in the eccentric hole. A slide bush to be installed and a ring for closing an annular gap between the upper end portion of the shaft and the slide bush from above are further provided, and the first bearing and the second bearing are in the axial direction. It was decided that the installation areas would at least partially overlap.

According to the present invention, it is possible to provide a scroll compressor or the like having high performance and reliability.

It is a vertical sectional view of the scroll compressor which concerns on 1st Embodiment. It is a partially enlarged view of the region K shown in FIG. 1 in the scroll compressor which concerns on 1st Embodiment. It is an exploded perspective view which includes the ring, the slide bush, the elastic body, and the upper end part of the shaft of the scroll compressor which concerns on 1st Embodiment. It is explanatory drawing about the force by the gas load of the scroll compressor which concerns on 1st Embodiment, centrifugal force, resultant force and the like. It is explanatory drawing which shows the relationship between the height position of the lower end of a ring, and the height position of the upper end of a main bearing in the scroll compressor which concerns on 1st Embodiment. It is explanatory drawing which shows the cross section in the vicinity of the upper end part of the shaft provided in the scroll compressor which concerns on 2nd Embodiment. FIG. 3 is an exploded perspective view including a ring, a slide bush, an elastic body, and an upper end portion of a shaft of the scroll compressor according to the second embodiment. It is a vertical sectional view of the scroll compressor which concerns on 3rd Embodiment. It is a block diagram of the refrigerant circuit of the air conditioner which concerns on 4th Embodiment.

<< First Embodiment >>
<Structure of scroll compressor>
FIG. 1 is a vertical sectional view of the scroll compressor 100 according to the first embodiment.
The scroll compressor 100 shown in FIG. 1 is a device that compresses a gaseous refrigerant. As shown in FIG. 1, the scroll compressor 100 includes a closed container 1, a compression mechanism unit 2, a shaft 3, an electric motor 4, an old dam ring 5, balance weights 6a and 6b, a fixing member 7, and a sub. It includes a frame 8, legs 9, and a power supply terminal 10. Further, in addition to the above-described configuration, the scroll compressor 100 includes a main bearing 11 (first bearing), a swivel bearing 12 (second bearing), a slide bush 13, a ring 14, and an elastic body 15. I have.

The closed container 1 is a shell-shaped container that houses the compression mechanism portion 2, the shaft 3, the electric motor 4, and the like, and is substantially sealed. Lubricating oil for improving the lubricity of the scroll compressor 100 is sealed in the closed container 1, and is stored as an oil sump R at the bottom of the closed container 1. The closed container 1 includes a cylindrical tubular chamber 1a, a lid chamber 1b that closes the upper side of the tubular chamber 1a, and a bottom chamber 1c that closes the lower side of the tubular chamber 1a.

As shown in FIG. 1, a suction pipe Pa is inserted and fixed in the lid chamber 1b of the closed container 1. The suction pipe Pa is a pipe that guides the refrigerant to the suction port J1 of the compression mechanism unit 2. Further, a discharge pipe Pb is inserted and fixed in the cylinder chamber 1a of the closed container 1. The discharge pipe Pb is a pipe that guides the refrigerant compressed by the compression mechanism unit 2 to the outside of the scroll compressor 100.

The compression mechanism unit 2 is a mechanism that compresses the refrigerant as the shaft 3 rotates. The compression mechanism unit 2 includes a frame 21, a fixed scroll 22, and a swivel scroll 23, and is arranged in the upper space inside the closed container 1.

The frame 21 is a member that supports the swivel scroll 23, and is fixed inside the closed container 1. That is, the frame 21 is fixed to the cylinder chamber 1a by welding or the like. The frame 21 is provided with a shaft insertion hole hf through which the upper end portion 3b of the shaft 3 is inserted.

Further, the frame 21 is provided with a back pressure chamber Sb. The back pressure chamber Sb is a space having a predetermined intermediate pressure between the suction pressure and the discharge pressure, and is provided on the back surface side of the swivel scroll 23. The back pressure chamber Sb has a function of generating an axially upward force that pushes the swivel scroll 23 against the fixed scroll 22 against an axially downward force that tries to separate the swivel scroll 23 from the fixed scroll 22 by compressing the refrigerant. Have. A back pressure hole hb (see FIG. 2) that penetrates the swivel scroll 23 in the axial direction is provided so as to communicate with the back pressure chamber Sb.

The frame 21 is provided with the above-mentioned back pressure chamber Sb, and is provided with a third oil supply flow path h3 for guiding the lubricating oil that lubricated the main bearing 11 (first bearing) to the back pressure chamber Sb. In the main bearing 11, a hole hr (see FIG. 2) for guiding the lubricating oil to the back pressure chamber Sb is provided at a position corresponding to the third oil supply flow path h3. Further, a seal ring r1 (see FIG. 2) is provided to partition the back pressure chamber Sb from the space hu (see FIG. 2) above the shaft 3.

The fixed scroll 22 shown in FIG. 1 is a member that forms a compression chamber Sp together with the swivel scroll 23 described below. As shown in FIG. 1, the fixed scroll 22 includes a base plate 22a and a fixed wrap 22b. The fixed scroll 22 is fastened to the frame 21 with bolts B1 and is fixed to the inside of the closed container 1.

The base plate 22a is a thick member having a circular shape in a plan view. In addition, in order to secure a region Sa (a circular region in the bottom view) in which the swivel lap 23b swivels with respect to the fixed lap 22b, the vicinity of the center of the lower surface of the base plate 22a is predeterminedly recessed upward. Further, a suction port J1 through which the refrigerant is guided via the suction pipe Pa is provided at a predetermined position on the base plate 22a.

The fixed wrap 22b has a spiral shape and extends downward from the base plate 22a in the above-mentioned region Sa. On the lower surface of the base plate 22a, the radial outer portion of the region Sa and the lower end of the fixed wrap 22b are substantially flush with each other.

The swivel scroll 23 is a member that forms a compression chamber Sp between the swivel scroll 23 and the fixed scroll 22 by its movement (swivel), and is provided between the frame 21 and the fixed scroll 22. The swivel scroll 23 includes a disk-shaped end plate 23a, a spiral swirl wrap 23b erected on the end plate 23a, and a swivel shaft 23c extending downward from the vicinity of the center of the end plate 23a. The swivel wrap 23b is a member that forms a compression chamber Sp together with the fixed lap 22b. The swivel shaft 23c has a columnar shape and is fitted into the eccentric hole he of the upper end portion 3b of the shaft 3.

Then, the spiral fixed wrap 22b and the spiral swirling wrap 23b mesh with each other to form a compression chamber Sp between the fixed lap 22b and the swirling lap 23b. The compression chamber Sp is a space for compressing the gaseous refrigerant, and is formed on the outer line side and the inner line side of the swirl lap 23b, respectively. Further, near the center of the base plate 22a of the fixed scroll 22, a discharge port J2 for guiding the refrigerant compressed in the compression chamber Sp to the upper space Su in the closed container 1 is provided.

The shaft 3 is a shaft that rotates integrally with the rotor 4b of the motor 4, and extends in the vertical direction. As shown in FIG. 1, the shaft 3 includes a main shaft 3a, an upper end portion 3b, and a lower end portion 3c. The spindle 3a is coaxially fixed to the rotor 4b of the electric motor 4, and rotates integrally with the rotor 4b. The upper end portion 3b is a portion extending upward from the main shaft 3a, and has a bottomed cylindrical shape that opens upward. In the example of FIG. 1, the central axis of the outer peripheral surface of the upper end portion 3b is substantially coaxial with the central axis Z1 of the main axis 3a.

Further, the upper end portion 3b is provided with an eccentric hole he that fits into the swivel shaft 23c. Here, "fitting" between the swivel shaft 23c and the eccentric hole he means that the eccentric hole he and the swivel shaft 23c have a predetermined gap (a gap for providing the swivel bearing 12 and the slide bush 13). It means that they fit together. The eccentric hole he has a circular shape in a cross-sectional view, and its central axis Z2 (see FIG. 4) is eccentric with respect to the central axis Z1 (see FIG. 4) of the main axis 3a. Then, as the electric motor 4 is driven, the swivel shaft 23c rotates while being eccentric to the main shaft 3a.

In the eccentric hole of the upper end portion 3b, a first slide surface E1 (see FIG. 3) for guiding the movement of the slide bush 13 in a predetermined direction perpendicular to the central axis Z1 of the main shaft 3a of the shaft 3 is provided. ing. On the other hand, as shown in FIG. 1, the lower end portion 3c of the shaft 3 extends downward from the main shaft 3a. Further, the shaft 3 (that is, the main shaft 3a, the upper end portion 3b, and the lower end portion 3c) has a through hole 3d for guiding the lubricating oil. Then, the lubricating oil stored as the oil sump R in the closed container 1 rises through the through hole 3d and is guided to the eccentric hole he at the upper end portion 3b. Further, the through hole 3d is predeterminedly branched so that the lubricating oil is also supplied to the auxiliary bearing 8a and the like.

Lubricating oil rises through the through hole 3d due to the pressure difference between the motor chamber Sm and the back pressure chamber Sb, but a positive displacement pump, centrifugal pump, viscous pump, etc. are provided at the lower end 3c of the shaft 3. You may do so.

The motor 4 is a drive source for rotating the shaft 3, and is installed between the frame 21 and the subframe 8 in the axial direction. As shown in FIG. 1, the electric motor 4 includes a stator 4a and a rotor 4b. The stator 4a has a winding 41a and is fixed to the inner peripheral wall of the tubular chamber 1a. The rotor 4b is rotatably arranged inside the stator 4a in the radial direction. Further, the shaft 3 is fixed to the rotor 4b by press fitting or the like so as to be coaxial with the central axis Z1.

The old dam ring 5 is a ring-shaped member that receives the eccentric rotation of the swivel shaft 23c and swivels the swivel scroll 23 without rotating. The old dam ring 5 is provided between the frame 21 and the swivel scroll 23 in the axial direction.
The balance weights 6a and 6b are members for suppressing the vibration of the scroll compressor 100. In the example of FIG. 1, a balance weight 6a is installed on the upper side of the rotor 4b on the spindle 3a, and another balance weight 8b is installed on the lower surface of the rotor 4b.

The fixing member 7 is a member for fixing the position of the subframe 8, and is fixed to the inner peripheral wall of the closed container 1 by welding or the like.
The subframe 8 is a member that rotatably supports the lower portion of the main shaft 3a, and is fastened to the fixing member 7 with bolts B2. The subframe 8 is provided with a hole (not shown) into which the shaft 3 is inserted, and an auxiliary bearing 8a is installed on the peripheral wall surface of the hole.

The plurality of legs 9 are members that support the closed container 1 and are installed in the bottom chamber 1c.
The power supply terminal 10 is a terminal used for supplying electric power to the electric motor 4. The power supply terminal 10 is provided in the cylinder chamber 1a and is electrically connected to the winding 41a of the electric motor 4.
Next, the main bearing 11, the swivel bearing 12, the slide bush 13, the ring 14, and the elastic body 15 will be described with reference to FIG.

FIG. 2 is a partially enlarged view of the region K shown in FIG.
In FIG. 2, the flow of the lubricating oil is indicated by an arrow. The main bearing 11 (first bearing) shown in FIG. 2 rotatably supports the upper end portion 3b of the shaft 3 with respect to the frame 21 and is fixed (installed) to the shaft insertion hole hf of the frame 21 by press fitting or the like. ) Has been. As such a main bearing 11, for example, a cylindrical slide bearing is used. The main bearing 11 may be made of resin or metal.

The swivel bearing 12 (second bearing) rotatably supports the swivel shaft 23c with respect to the slide bush 13, and is fixed (installed) to the swivel shaft 23c by press fitting or the like. As such a swivel bearing 12, for example, a cylindrical slide bearing is used. The swivel bearing 12 may be made of resin or metal.

In the example of FIG. 2, the installation area Q2 of the swivel bearing 12 in the axial direction is included in the installation area Q1 of the main bearing 11. Specifically, the height position of the upper end of the swivel bearing 12 is slightly lower than the height position of the upper end of the main bearing 11, while the height position of the lower end of the swivel bearing 12 is the height of the lower end of the main bearing 11. It is higher than the position. That is, the swivel bearing 12 is included in the main bearing 11.

The positional relationship between the upper end and the lower end of the main bearing 11 and the swivel bearing 12 is not limited to those described above. That is, the main bearing 11 (first bearing) and the swivel bearing 12 (second bearing) may be configured such that the installation areas Q1 and Q2 in the axial direction at least partially overlap each other. Such a configuration is called a "double bearing structure".
The slide bush 13 is a member that moves the swivel scroll 23 in the radial direction (that is, the amount of eccentricity of the swivel scroll 23 is variable) by a gas load or centrifugal force acting on the swivel shaft 23c.

FIG. 3 is an exploded perspective view of the scroll compressor 100 including the ring 14, the slide bush 13, the elastic body 15, and the upper end portion 3b of the shaft 3.
As shown in FIG. 3, the slide bush 13 has a second slide surface E2 in which a cylindrical member is cut out in a predetermined plane (not shown) parallel to its central axis. The second slide surface E2 is a surface that slides on the first slide surface E1 of the upper end portion 3b of the shaft 3, and is arranged so as to face the first slide surface E1.

Then, as shown in FIG. 2, the slide bush 13 is inserted into the eccentric hole he of the upper end portion 3b of the shaft 3, and is installed on the radial outer side of the swivel bearing 12 (second bearing) in the eccentric hole he. .. In other words, the slide bush 13 is provided in the annular gap between the swivel bearing 12 and the inner peripheral surface of the upper end portion 3b of the shaft 3 in the radial direction. The inner diameter of the slide bush 13 is slightly larger than the outer diameter of the swivel bearing 12. Further, the outer diameter of the slide bush 13 is slightly smaller than the diameter of the eccentric hole he.

Then, the second slide surface E2 of the slide bush 13 slides with respect to the first slide surface E1 of the upper end portion 3b due to the gas load and centrifugal force accompanying the compression of the refrigerant, so that the swivel shaft 23c is moved in a predetermined direction. It has become. As such a slide bush 13, a metal one can be used.

The ring 14 shown in FIG. 2 closes the annular gap g1 between the upper end portion 3b of the shaft 3 and the slide bush 13 from above. As such a ring 14, for example, one made of metal is used. The ring 14 has an annular shape in a plan view and an inverted L shape in a vertical cross-sectional view. Then, the ring 14 is fixed to the inner peripheral edge of the upper end of the eccentric hole he by press fitting or the like. The inner peripheral edge of the upper end of the eccentric hole he (where the ring 14 is installed) has a circular shape, and the inner diameter of the ring 14 is appropriately set at the design stage based on the diameter of the inner peripheral edge.

The elastic body 15 shown in FIG. 3 urges the slide bush 13 toward the ring 14 (that is, upward). As shown in FIG. 2, the elastic body 15 is provided between the bottom surface of the eccentric hole he and the lower surface of the slide bush 13. As such an elastic body 15, for example, a wave washer that is annular (or C-shaped) in a plan view is used.

When the shaft 3 is rotated by the drive of the electric motor 4 shown in FIG. 1, the swivel shaft 23c fitted in the eccentric hole he swivels. As a result, the compression chamber Sp between the fixed scroll 22 and the swivel scroll 23 is reduced, and the refrigerant is compressed. The compressed refrigerant is discharged into the upper space Su in the closed container 1 through the discharge port J2 of the fixed scroll 22, and further, a predetermined flow path (shown) between the compression mechanism unit 2 and the closed container 1. It is guided to the motor chamber Sm via the). Then, the refrigerant guided to the motor chamber Sm is discharged to the outside of the closed container 1 via the discharge pipe Pb.

Here, the radial outward gas load force Fg (see FIG. 4) acting on the swivel scroll 23 is applied to the peripheral wall surface of the eccentric hole he of the swivel bearing 12, the slide bush 13, and the shaft 3 via the swivel shaft 23c. , And act on the main bearing 11 in sequence. Further, to explain including the reaction force of the gas load to the force Fg, the gas load force Fg (see FIG. 4) acts on the peripheral wall surface of the eccentric hole he via the swivel bearing 12 from the swivel shaft 23c, while the force Fg thereof acts on the peripheral wall surface. A reaction force (not shown) acts from the main bearing 11 to the upper end portion 3b (see FIG. 2) of the shaft 3.

As described above, the main bearing 11 and the swivel bearing 12 have a double bearing structure, and the installation area Q1 of the main bearing 11 and the installation area Q2 of the swivel bearing 12 overlap in the axial direction (FIG. 2). reference). Therefore, with respect to the force Fg of the gas load (see FIG. 4), the point of action on the swivel bearing 12 and the point of action on the main bearing 11 substantially coincide with each other in the axial direction, so that the shaft 3 is tilted. Almost no moment occurs. As a result, one-sided contact of the shaft 3 in the main bearing 11 or the like is suppressed, and the reliability of the main bearing 11 and the swivel bearing 12 can be improved.

Further, by adopting the double bearing structure described above, the axial length of the scroll compressor 100 is shortened as compared with the configuration (not shown) in which the swivel bearing 12 is arranged above the main bearing 11. , The miniaturization can be achieved. Further, since the length of the shaft 3 is relatively short, the balance weights 6a and 6b (see FIG. 1) can also be reduced. As a result, the deflection of the shaft 3 due to the centrifugal force is reduced, so that one-sided contact of the shaft 3 in the main bearing 11 or the like can be suppressed. By adopting the double bearing structure in this way, it is possible to suppress the inclination and deflection of the shaft 3 even when the scroll compressor 100 is driven at high speed.

FIG. 4 is an explanatory diagram (cross-sectional view) regarding a force Fg, a centrifugal force Fc, a resultant force F, and the like due to a gas load of the scroll compressor 100.
The alternate long and short dash line i1 in FIG. 4 indicates the eccentric direction of the eccentric hole he. Here, the eccentric direction is a direction in which the central axis Z2 of the swivel shaft 23c deviates from the central axis Z1 of the shaft 3. Further, the alternate long and short dash line i2 in FIG. 4 is a straight line parallel to the slide direction of the slide bush 13 and passing through the central axis Z2 of the swivel shaft 23c.

The force Fg due to the gas load is a force acting on the swivel shaft 23c with the compression of the refrigerant in the compression mechanism unit 2. The centrifugal force Fc is a radial outward inertial force acting on the swivel shaft 23c. The resultant force F is the resultant force of the force Fg due to the gas load and the centrifugal force Fc. The component force F1 is a component force in the resultant force F that is parallel to the second slide surface E2 and is perpendicular to the central axis Z2 of the swivel shaft 23c.

As shown in FIG. 4, the first slide surface E1 of the upper end portion 3b of the shaft 3 forms a predetermined angle α with respect to the eccentric direction (dotted chain line i1) of the eccentric hole he provided in the upper end portion 3b. It is provided in. Then, the slide bush 13 is guided by the first slide surface E1 of the upper end portion 3b, and moves in the direction of the component force F1 by the resultant force F of the force Fg due to the gas load and the centrifugal force Fc.

Further, as the slide bush 13 moves, the swivel scroll 23 (see FIG. 1) also moves in the direction of the component force F1, so that the swivel lap 23b (see FIG. 1) is pressed against the fixed lap 22b (see FIG. 1). .. As a result, even when the scroll compressor 100 is rotated at a low speed, the radial gap between the swivel lap 23b and the fixed lap 22b becomes substantially zero, so that leakage loss can be reduced. As a result, it is possible to reduce the leakage loss during low-speed operation, which is particularly important for reducing the annual power consumption, and to improve the efficiency and performance of the scroll compressor 100.

Note that the force Fg of the gas load and the centrifugal force Fc change depending on the operating conditions of the scroll compressor 100, and the resultant force F also changes accordingly. Therefore, in consideration of the operating conditions of the scroll compressor 100, the predetermined angle α shown in FIG. 4 is appropriately set at the design stage. For example, even when the rotation speed of the scroll compressor 100 is the minimum and the force Fg of the gas load is the maximum, the contact force from the swivel lap 23b to the fixed lap 22b becomes a positive value. A predetermined angle α is set.

Next, the flow of lubricating oil will be explained. The lubricating oil stored as the oil sump R in the bottom of the closed container 1 shown in FIG. 1 is guided to the gap between the peripheral wall surface of the eccentric hole he and the swivel shaft 23c via the through hole 3d of the shaft 3. .. Here, as described above, the outlet side (upper side) of the annular gap g1 (see FIG. 2) between the peripheral wall surface of the eccentric hole he and the outer peripheral surface of the slide bush 13 is closed by the ring 14. .. Further, the elastic body 15 presses the slide bush 13 toward the ring 14. Therefore, the lubricating oil hardly flows through the annular gap g1.

As a result, a sufficient amount of lubricating oil can be supplied to the first lubrication flow path h1 (see FIG. 2), which is an annular gap between the swivel bearing 12 and the slide bush 13. Since the radial distance between the swivel bearing 12 and the slide bush 13 is very small, the first lubrication flow path h1 (see also FIG. 2) is not shown in the cross-sectional view of FIG.

Further, since the swivel bearing 12 has a smaller diameter than the main bearing 11, the moving speed (referred to as peripheral speed) of the outer peripheral surface of the swivel bearing 12 when the swivel shaft 23c is rotating is higher than the peripheral speed of the main bearing 11. Is also small. Therefore, in the swivel bearing 12, it is difficult to secure a predetermined oil film pressure, and it is difficult to form an oil film of the lubricating oil, so that a severe sliding state is likely to occur.

If the outlet side of the annular gap g1 (see FIG. 2) described above is not blocked by the ring 14, lubricate both the path of this gap g1 and the first oil supply flow path h1 on the swivel bearing 12 side. Passes through. Then, the slewing bearing 12, which tends to be in a harsh sliding state, may be insufficiently lubricated. On the other hand, in the first embodiment, since the ring 14 for closing the annular gap g1 is provided, the above-mentioned problems can be prevented.

As shown by the arrow in FIG. 2, the lubricating oil that has passed through the annular first oil supply flow path h1 between the swivel bearing 12 and the slide bush 13 passes through the space hu above the upper end portion 3b of the shaft 3. , Guided to the second lubrication flow path h2. The second lubrication flow path h2 is an annular gap between the outer peripheral surface of the upper end portion 3b of the shaft 3 and the main bearing 11. The main bearing 11 is lubricated by the lubricating oil flowing through the second lubrication flow path h2. After passing through the main bearing 11, the lubricating oil is guided to the back pressure chamber Sb via the third oil supply flow path h3 provided in the frame 21.
As described above, in the configuration in which the main bearing 11 (first bearing) is installed on the peripheral wall surface of the shaft insertion hole hf, the annular first lubrication flow path between the swivel bearing 12 (second bearing) and the slide bush 13 is provided. After the lubricating oil has passed through h1, the lubricating oil is guided to the annular second oil supply flow path h2 between the outer peripheral surface of the upper end portion 3b of the shaft 3 and the main bearing 11, and further provided on the frame 21. Lubricating oil is guided to the back pressure chamber Sb via the third lubrication flow path h3.

In a configuration in which the main bearing 11 (first bearing) is installed on the peripheral wall surface of the shaft insertion hole hf, the annular first oil supply flow path h1 between the swivel bearing 12 (second bearing) and the slide bush 13 is provided. It is preferable that the area when the annular second oil supply flow path h2 between the outer peripheral surface of the upper end portion 3b of the shaft 3 and the main bearing 11 is viewed in a plan view is smaller than the area when viewed in a plan view. According to such a configuration, since the second lubrication flow path h2 near the back pressure chamber Sb is narrowed down as compared with the first lubrication flow path h1, lubrication is performed in the process of passing through the second lubrication flow path h2. While the oil is depressurized, the lubricating oil is hardly depressurized in the first oil supply flow path h1 on the upstream side thereof. As a result, the pressure of the lubricating oil immediately after lubricating the swivel shaft 23c becomes substantially equal to the discharge pressure. This makes it possible to prevent the shaft 3 from floating due to the pressure difference between the shaft 3 and the space hu on the upper side and the motor chamber Sm (see FIG. 1). Therefore, it is possible to prevent the shaft 3 from coming into contact with the end plate 23a and the swivel shaft 23c of the swivel scroll 23.

Further, as described above, since the lubricating oil is hardly depressurized in the vicinity of the swivel bearing 12, the foaming phenomenon in which the refrigerant foams from the lubricating oil can be prevented. As a result, the swivel bearing 12 is lubricated by the lubricating oil containing almost no air bubbles in the refrigerant, so that the swivel bearing 12 that tends to be in a harsh sliding state can be appropriately lubricated.

Further, the cross-sectional area of the third refueling flow path h3 is smaller than the area when the annular first refueling flow path h1 between the swivel bearing 12 (second bearing) and the slide bush 13 is viewed in a plan view. Is preferable. As described above, the third lubrication flow path h3 is a flow path that guides the lubricating oil that lubricated the main bearing 11 (first bearing) to the back pressure chamber Sb. According to such a configuration, since the third refueling flow path h3 near the back pressure chamber Sb is narrowed down as compared with the first refueling flow path h1, the refrigerant is hardly depressurized in the vicinity of the swivel bearing 12. Therefore, it is possible to prevent the shaft 3 from floating and to prevent the foaming phenomenon of the refrigerant from the lubricating oil.

FIG. 5 is an explanatory diagram showing the relationship between the height position H1 at the lower end of the ring 14 and the height position H2 at the upper end of the main bearing 11.
Note that FIG. 5 is an enlarged view of a thin portion (a portion on the right side of the paper surface with respect to the swivel shaft 23c) at the upper end portion 3b of the shaft 3 shown in FIG. As shown in FIG. 5, it is preferable that the height position H1 at the lower end of the ring 14 is higher than the height position H2 at the upper end of the main bearing 11 (first bearing).

For example, when the ring 14 is press-fitted into the eccentric hole he of the shaft 3, the outer peripheral side of the eccentric hole he is slightly deformed and expands radially outward (on the right side of the paper in FIG. 5). Here, as described above, the height position H1 at the lower end of the ring 14 is higher than the height position H2 at the upper end of the main bearing 11. As a result, even when the upper end portion 3b of the shaft 3 expands radially outward, the gap between the upper end portion 3b and the main bearing 11 (that is, the second oil supply flow path h2) becomes narrower, or the upper end portion 3b becomes open. It is possible to suppress contact with the main bearing 11.

<Effect>
According to the first embodiment, as shown in FIG. 2, the main bearing 11 and the swivel bearing 12 have a double bearing structure, and a slide bush 13 is provided on the radial outer side of the swivel bearing 12. .. As a result, the inclination and bending of the shaft 3 can be suppressed even when the scroll compressor 100 is driven at high speed. Further, even when the scroll compressor 100 is driven at a low speed, the radial gap between the swivel lap 23b and the fixed lap 22b becomes substantially zero, so that leakage loss can be reduced. Therefore, it is possible to achieve both reliability when the scroll compressor 100 is driven at a high speed and high efficiency when the scroll compressor 100 is driven at a low speed.

Further, as shown in FIG. 2, a ring 14 is provided to close the annular gap g1 between the upper end portion 3b of the shaft 3 and the slide bush 13 from above. As a result, a sufficient amount of lubricating oil can be supplied to the annular first lubrication flow path h1 between the swivel bearing 12 and the slide bush 13. Therefore, the swivel bearing 12, which tends to be in a severe sliding state, can be sufficiently lubricated.

Further, an elastic body 15 for urging the slide bush 13 toward the ring 14 is provided. As a result, the slide bush 13 is pressed against the ring 14, so that rattling and noise of the slide bush 13 can be prevented, and leakage of the lubricating oil through the annular gap g1 can be suppressed. As described above, according to the first embodiment, it is possible to provide the scroll compressor 100 having high performance and reliability.

<< Second Embodiment >>
The first aspect of the second embodiment is that oil grooves ua and ub (see also FIG. 7) are provided on the first slide surface E1 of the eccentric hole he provided at the upper end portion 3Ab of the shaft 3A (see FIG. 6). It is different from the embodiment. Others (overall configuration of the scroll compressor, etc .: see FIG. 1) are the same as those in the first embodiment. Therefore, a part different from the first embodiment will be described, and a description of the overlapping part will be omitted.

FIG. 6 is an explanatory view showing a cross section in the vicinity of the upper end portion 3Ab of the shaft 3A included in the scroll compressor 100A according to the second embodiment.
In FIG. 6, each configuration other than the upper end portion 3Ab of the shaft 3A is the same as that of the first embodiment (see FIGS. 1 and 2), and thus the description thereof will be omitted. While the scroll compressor 100A is being driven, the second slide surface E2 of the slide bush 13 is pressed against the first slide surface E1 of the upper end portion 3Ab by the resultant force F of the gas load force Fg and the centrifugal force Fc (see FIG. 4). Be done. As a result, the first slide surface E1 and the second slide surface E2 slide with each other, although the displacement is small. Therefore, in the second embodiment, the oil grooves ua and ub are provided on the first slide surface E1 of the upper end portion 3Ab.

FIG. 7 is an exploded perspective view including the ring 14, the slide bush 13, the elastic body 15, and the upper end portion 3Ab of the shaft 3A of the scroll compressor 100A.
In the example of FIG. 7, two oil grooves ua and ub for guiding the lubricating oil are provided on the first slide surface E1 of the eccentric hole he along the axial direction. As a result, the lubricating oil flows through the gap between the second slide surface E2 of the slide bush 13 and the oil grooves ua and ub wall surfaces. As a result, the first slide surface E1 and the second slide surface E2 that slide with a minute displacement are appropriately lubricated, so that problems such as galling and seizure can be prevented.

Further, since the lubricating oil flows upward through the oil grooves ua and ub, new lubricating oil continues to be supplied to the oil grooves ua and ub. As a result, it is possible to suppress an excessive temperature rise of the lubricating oil on the first slide surface E1 and the second slide surface E2. Further, by appropriately setting the depth and the width in the circumferential direction of the oil grooves ua and ub at the design stage, an appropriate amount of lubricating oil can be supplied to the oil grooves ua and ub.

In FIG. 6, a predetermined gap between the wall surface of the oil grooves ua and ub and the second slide surface E2 and the space hu on the upper side of the shaft 3 (see FIG. 2) communicate with each other (that is, in FIG. 2). The upper side of the oil grooves ua and ub is open), but the configuration is not limited to this. For example, the upper side of the oil grooves ua and ub may be blocked by the ring 14. Even with such a configuration, since the gaps between the oil grooves ua and ub are filled with the lubricating oil while the scroll compressor 100A is being driven, the first slide surface E1 and the second slide surface E2 are appropriately lubricated.

<Effect>
According to the second embodiment, since the oil grooves ua and ub are provided in the first slide surface E1 of the eccentric hole he, the first slide surface E1 and the second slide surface E2 are appropriately lubricated. As a result, problems such as galling and seizure due to the movement (sliding) of the slide bush 13 can be prevented, and the reliability of the scroll compressor 100A can be further improved as compared with the first embodiment.

<< Third Embodiment >>
The third embodiment is different from the first embodiment in that the upper end portion 3Bb of the shaft 3B of the scroll compressor 100B (see FIG. 8) and the remaining portion of the shaft 3B are configured as separate parts. ing. The other points (overall configuration of the scroll compressor, etc.) are the same as those in the first embodiment. Therefore, a part different from the first embodiment will be described, and a description of the overlapping part will be omitted.

FIG. 8 is a vertical sectional view of the scroll compressor 100B according to the third embodiment.
As shown in FIG. 8, the shaft 3B of the scroll compressor 100B includes a main shaft 3a, an upper end portion 3Bb, and a lower end portion 3c. The upper end portion 3Bb is a separate part from the main shaft 3a. That is, in the shaft 3B, the upper end portion 3Bb provided with the eccentric hole he and the remaining portion (main shaft 3a and lower end portion 3c) of the shaft 3B are composed of separate parts. Then, the upper end portion 3Bb is fixed to the main shaft 3a by press-fitting into the main shaft 3a or the like.

Since a severe sliding state is likely to occur at the upper end portion 3Bb, it is desirable that a predetermined heat treatment or surface treatment is applied to the upper end portion 3Bb in order to ensure reliability of the scroll compressor 100B at high speed rotation. On the other hand, heat treatment or the like may not be particularly required for the main shaft 3a and the lower end portion 3c of the shaft 3B. In such a case, as shown in FIG. 8, by making the upper end portion 3Bb of the shaft 3B a separate part, the target to be heat-treated or the like is only the upper end portion 3Bb. Therefore, the manufacturing cost of the scroll compressor 100B can be reduced as compared with the case where the entire shaft 3B is heat-treated.

<Effect>
According to the third embodiment, since the upper end portion 3Bb of the shaft 3B and the remaining portion are separate parts, when the upper end portion 3Bb is heat-treated or surface-treated, it is not particularly necessary to heat-treat the remaining portion. .. Therefore, the manufacturing cost of the scroll compressor 100B can be reduced.

<< Fourth Embodiment >>
In the fourth embodiment, the air conditioner W (refrigeration cycle device: see FIG. 9) including the scroll compressor 100 (see FIG. 1) described in the first embodiment will be described.

FIG. 9 is a block diagram of the refrigerant circuit G of the air conditioner W according to the fourth embodiment.
The solid line arrow in FIG. 9 indicates the flow of the refrigerant during the heating operation.
On the other hand, the broken line arrow in FIG. 9 indicates the flow of the refrigerant during the cooling operation.
The air conditioner W is a device that performs air conditioning such as cooling and heating. As shown in FIG. 9, the air conditioner W includes a scroll compressor 100, an outdoor heat exchanger Eo, an outdoor fan Fo, an expansion valve Ve, a four-way valve Vf, an indoor heat exchanger Ei, and an indoor fan. It is equipped with Fi.

In the example shown in FIG. 9, the scroll compressor 100, the outdoor heat exchanger Eo, the outdoor fan Fo, the expansion valve Ve, and the four-way valve Vf are provided in the outdoor unit Wo. On the other hand, the indoor heat exchanger Ei and the indoor fan Fi are provided in the indoor unit Wi.

The scroll compressor 100 is a device that compresses a gaseous refrigerant, and has the same configuration as that of the first embodiment (see FIG. 1).
The outdoor heat exchanger Eo is a heat exchanger in which heat is exchanged between the refrigerant passing through the heat transfer tube (not shown) and the outside air sent from the outdoor fan Fo.
The outdoor fan Fo is a fan that sends outside air to the outdoor heat exchanger Eo. The outdoor fan Fo includes an outdoor fan motor Mo which is a drive source, and is installed in the vicinity of the outdoor heat exchanger Eo.

The indoor heat exchanger Ei is a heat exchanger in which heat is exchanged between the refrigerant passing through the heat transfer tube (not shown) and the indoor air (air in the air conditioning target space) sent from the indoor fan Fi. Is.
The indoor fan Fi is a fan that sends indoor air to the indoor heat exchanger Ei. The indoor fan Fi includes an indoor fan motor Mi as a drive source, and is installed in the vicinity of the indoor heat exchanger Ei.

The expansion valve Ve is a valve that reduces the pressure of the refrigerant condensed by the "condenser" (one of the outdoor heat exchanger Eo and the indoor heat exchanger Ei). The refrigerant decompressed by the expansion valve Ve is guided to an "evaporator" (the other of the outdoor heat exchanger Eo and the indoor heat exchanger Ei).

The four-way valve Vf is a valve that switches the flow path of the refrigerant according to the operation mode of the air conditioner W. For example, during cooling operation (see the dashed arrow in FIG. 9), the scroll compressor 100, the outdoor heat exchanger Eo (condenser), the expansion valve Ve, and the indoor heat exchanger Ei (evaporator) are four-way valves. In the refrigerant circuit G sequentially connected via Vf, the refrigerant circulates in the refrigeration cycle.

On the other hand, during the heating operation (see the solid line arrow in FIG. 9), the scroll compressor 100, the indoor heat exchanger Ei (condenser), the expansion valve Ve, and the outdoor heat exchanger Eo (evaporator) are four-way valves. In the refrigerant circuit G sequentially connected via Vf, the refrigerant circulates in the refrigeration cycle.

As described above, in the fourth embodiment, the refrigerant circulates sequentially through the scroll compressor 100, the "condenser", the expansion valve Ve, and the "evaporator" in the refrigerant circuit. Devices such as the scroll compressor 100, the outdoor fan Fo, the expansion valve Ve, and the indoor fan Fi are driven based on a command from a control device (not shown).

<Effect>
According to the fourth embodiment, the air conditioner W includes a scroll compressor 100 having high performance and reliability. As a result, the performance and reliability of the air conditioner W as a whole can be improved.

≪Variation example≫
Although the scroll compressor 100 and the air conditioner W according to the present invention have been described above in each embodiment, the present invention is not limited to these descriptions, and various modifications can be made.
For example, in the first embodiment (see FIG. 2), the configuration in which the main bearing 11 (first bearing) is installed in the shaft insertion hole hf has been described, but the present invention is not limited to this. That is, the main bearing 11 may be installed at the upper end portion 3b of the shaft 3. In this way, in the configuration in which the main bearing 11 (first bearing) is installed at the upper end portion 3b of the shaft 3, the annular first lubrication flow path h1 between the swivel bearing 12 (second bearing) and the slide bush 13 After the lubricating oil has flowed through, the lubricating oil is guided to the annular second lubrication flow path h2 between the peripheral wall surface of the shaft insertion hole hf and the main bearing 11, and further, the third lubrication provided in the frame 21. Lubricating oil is guided to the back pressure chamber Sb via the flow path h3. Even with such a configuration, the same effect as that of the first embodiment is obtained.
Further, in a configuration in which the main bearing 11 (first bearing) is installed at the upper end portion 3b of the shaft 3, the annular first lubrication flow path h1 between the swivel bearing 12 (second bearing) and the slide bush 13 (FIG. 2) is smaller than the area when the annular second oil supply flow path (not shown) between the peripheral wall surface of the shaft insertion hole hf and the main bearing 11 is viewed in a plan view. Is preferable. According to such a configuration, the second refueling flow path (not shown) near the back pressure chamber Sb is narrowed as compared with the first refueling flow path h1, so that the shaft 3 floats due to the pressure difference. Can be prevented. The same can be said for the second and third embodiments.

Further, in the first embodiment, the configuration in which the swivel bearing 12 is fixed to the swivel shaft 23c has been described, but the present invention is not limited to this. For example, the swivel bearing 12 may be fixed to the inner peripheral surface of the slide bush 13, while the swivel shaft 23c and the swivel bearing 12 may slide. The same can be said for the second and third embodiments.

Further, in the first embodiment, the flow path cross-sectional area of the lubricating oil is provided by providing a predetermined oil groove (not shown) serving as an oil supply passage on the outer peripheral surface of the swivel bearing 12 or the inner peripheral surface of the slide bush 13. May be sufficiently secured and the pressure drop of the lubricating oil may be suppressed. The same can be said for the second and third embodiments.

Further, in the second embodiment, a configuration in which two oil grooves ua and ub are provided on the first slide surface E1 of the upper end portion 3Ab of the shaft 3A (see FIG. 7) has been described, but the present invention is not limited to this. For example, the number of oil grooves provided on the first slide surface E1 may be one, or may be three or more. Further, instead of the first slide surface E1 of the upper end portion 3Ab, one or a plurality of oil grooves may be provided on the second slide surface E2 of the slide bush 13. Further, the oil groove may be provided on both the first slide surface E1 and the second slide surface E2. That is, the first slide surface E1 and / or the second slide surface E2 may be provided with one or a plurality of oil grooves for guiding the lubricating oil along the axial direction.

Further, the air conditioner W (see FIG. 13) described in the fourth embodiment can be applied to various types of air conditioners such as room air conditioners, package air conditioners, and multi air conditioners for buildings.
Further, in the fourth embodiment, the air conditioner W (refrigeration cycle device: see FIG. 9) including the compressor 100 has been described, but the present invention is not limited to this. For example, the fourth embodiment can be applied to other "refrigerating cycle devices" such as a refrigerator, a water heater, an air-conditioned water heater, a chiller, and a refrigerator.

Further, in each embodiment, the configuration in which the scroll compressor 100 is installed vertically has been described, but the present invention is not limited to this. For example, each embodiment can be applied to a configuration in which the scroll compressor 100 is installed horizontally or diagonally.

Further, in each embodiment, the case where the refrigerant is compressed by the scroll compressor 100 has been described, but the present invention is not limited to this. That is, each embodiment can be applied even when a predetermined gas other than the refrigerant is compressed by the scroll compressor 100.

Moreover, each embodiment can be combined appropriately. For example, the second embodiment and the third embodiment are combined, oil grooves ua and ub are provided on the first slide surface E1 (second embodiment: see FIG. 7), and the upper end portion 3Bb of the shaft 3B and the rest. The portion may be a separate part (third embodiment: see FIG. 8).
Further, the second embodiment and the fourth embodiment are combined so that the air conditioner W (fourth embodiment: see FIG. 9) is provided with the scroll compressor 100A (second embodiment: see FIG. 7). May be good. Similarly, it is also possible to combine the third embodiment and the fourth embodiment.

Further, each embodiment is described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the configurations described. Further, it is possible to appropriately add / delete / replace other configurations with respect to a part of the configurations of each embodiment.
In addition, the above-mentioned mechanism and configuration show what is considered necessary for explanation, and do not necessarily show all the mechanisms and configurations in the product.

1 Airtight container 2 Compression mechanism 21 Frame 22 Fixed scroll 22a Base plate 22b Fixed wrap 23 Swivel scroll 23a End plate 23b Swivel lap 23c Swivel shaft 3,3A, 3B Shaft 3a Main shaft 3b, 3Ab, 3Bb Upper end 3d Through hole 4 Motor Stator 4b Rotor 11 Main bearing (1st bearing)
12 Swivel bearing (second bearing)
13 Slide bush 14 Ring 15 Elastic body 100, 100A, 100B Scroll compressor E1 1st slide surface E2 2nd slide surface Ei Indoor heat exchanger (evaporator / condenser)
Eo outdoor heat exchanger (condensor / evaporator)
G Refrigerant circuit g1 Gap h1 1st refueling flow path h2 2nd refueling flow path h3 3rd refueling flow path he Eccentric hole hf Shaft insertion hole
Q1 installation area (installation area of the first bearing)
Q2 installation area (installation area of the second bearing)
Sb Back pressure chamber Sp Compression chamber ua, ub Oil groove Ve Expansion valve W Air conditioner (refrigeration cycle device)
Z1 center axis

Claims (11)

1. With a closed container
   With a fixed scroll that has a spiral fixing wrap and is fixed inside the closed container,
   A swirl scroll having a swirl-shaped swirl wrap that forms a compression chamber with the fixed wrap and a swivel axis,
   The frame that supports the swivel scroll and
   Motors with stators and rotors,
   It has a through hole for guiding lubricating oil, and is equipped with a shaft that rotates integrally with the rotor.
   An eccentric hole that fits into the swivel shaft is provided at the upper end of the shaft.
   The frame is provided with a shaft insertion hole through which the upper end portion of the shaft is inserted.
   A first bearing installed in the shaft insertion hole or at the upper end of the shaft.
   The second bearing installed on the swivel shaft and
   A slide bush installed radially outside the second bearing in the eccentric hole,
   Further provided with a ring that closes the annular gap between the upper end of the shaft and the slide bush from above.
   The first bearing and the second bearing are scroll compressors in which installation areas in the axial direction overlap at least partially.
2. In the configuration in which the first bearing is installed on the peripheral wall surface of the shaft insertion hole, after the lubricating oil has passed through the annular first oil supply flow path between the second bearing and the slide bush, the shaft is used. Lubricating oil is guided to the annular second lubrication flow path between the outer peripheral surface of the upper end portion and the first bearing, and further lubricates the back pressure chamber through the third lubrication flow path provided in the frame. The scroll compressor according to claim 1, wherein the oil is guided.
3. In the configuration in which the first bearing is installed at the upper end of the shaft, after the lubricating oil has passed through the annular first oil supply flow path between the second bearing and the slide bush, the shaft insertion hole is inserted. Lubricating oil is guided to the annular second lubrication flow path between the peripheral wall surface of the bearing and the first bearing, and further, the lubricating oil is guided to the back pressure chamber through the third lubrication flow path provided in the frame. The scroll compressor according to claim 1, wherein the bearing is made.
4. In a configuration in which the first bearing is installed on the peripheral wall surface of the shaft insertion hole, the shaft is larger than the area when the annular first oil supply flow path between the second bearing and the slide bush is viewed in a plan view. The scroll compressor according to claim 1, wherein the area of the annular second refueling flow path between the outer peripheral surface of the upper end portion and the first bearing is smaller when viewed in a plan view.
5. In a configuration in which the first bearing is installed at the upper end of the shaft, the shaft insertion is larger than the area when the annular first oil supply flow path between the second bearing and the slide bush is viewed in a plan view. The scroll compressor according to claim 1, wherein the area of the annular second lubrication flow path between the peripheral wall surface of the hole and the first bearing is smaller when viewed in a plan view.
6. The frame is provided with a predetermined back pressure chamber, and is provided with a third oil supply flow path that guides the lubricating oil that lubricated the first bearing to the back pressure chamber.
   The claim is characterized in that the cross-sectional area of the flow path of the third refueling flow path is smaller than the area when the annular first refueling flow path between the second bearing and the slide bush is viewed in a plan view. The scroll compressor according to 1.
7. The scroll compressor according to claim 1, further comprising an elastic body provided between the bottom surface of the eccentric hole and the lower surface of the slide bush to urge the slide bush toward the ring. ..
8. The scroll compressor according to claim 1, wherein the height position of the lower end of the ring is higher than the height position of the upper end of the first bearing.
9. The eccentric hole is provided with a first slide surface that guides the movement of the slide bush in a predetermined direction perpendicular to the central axis of the main shaft of the shaft.
   The slide bush is provided with a second slide surface that is arranged so as to face the first slide surface and slides with respect to the first slide surface.
   The first aspect of claim 1, wherein the first slide surface and / or the second slide surface is provided with one or a plurality of oil grooves for guiding the lubricating oil along the axial direction. Scroll compressor.
10. The scroll compressor according to claim 1, wherein in the shaft, the upper end portion and the remaining portion of the shaft are made of separate parts.
11. The scroll compressor according to any one of claims 1 to 10 is provided.
    A refrigerating cycle apparatus including a refrigerant circuit in which a refrigerant circulates sequentially through the scroll compressor, a condenser, an expansion valve, and an evaporator.

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