Scroll compressor

Abstract

A scroll compressor is provided to reduce the overall imbalance of the movable system components, including a drive shaft and parts fixed or connected to the drive shaft. In the scroll compressor (10), a shaft balancer (31) integrally provided with the drive shaft (30) has a first counterweight (33) with the center line (CL0) of the drive shaft (30) located on the side opposite to the eccentric pin (71), and a bushing balancer (721) integrally provided with the eccentric bushing (72) has a second counterweight (723) located radially outside the eccentric bushing (72) and with the center line (CL2) of the eccentric bushing (72) located on the side opposite to the center line (CL1) of the eccentric pin (71). When viewed axially from the drive shaft (30), the second counterweight (723) is formed symmetrically with respect to an imaginary straight line passing through the center of the drive shaft (30) and the center of the eccentric bushing (72), while the first counterweight (33) is formed asymmetrically with respect to the aforementioned imaginary straight line.

Description

Technical Field

[0001] This invention relates to a scroll compressor. Background Technology

[0002] A scroll compressor has a fixed scroll and a rotating scroll arranged in a manner where their scroll walls mesh with each other. The scroll compressor compresses the fluid drawn into the compression chamber by causing the rotating scroll to revolve relative to the fixed scroll, thus changing the volume of the compression chamber formed between the scroll walls. Additionally, scroll compressors typically include a balancer (also called a counterweight) to reduce vibrations caused by the revolving motion of the rotating scroll.

[0003] For example, in the scroll compressor described in Patent Document 1, the drive force transmission mechanism that transmits drive force to the scroll includes: a drive shaft that is driven to rotate; a crank pin provided at one end of the drive shaft; an eccentric bushing that is externally fitted to the crank pin in a rotatable manner and internally fitted to a cylindrical portion provided on the back side of the scroll via a bearing in a rotatable manner, and a balancer (counterweight) integrally provided on the eccentric bushing.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-100246 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] In recent years, with the increasing rotational speed of scroll compressors, there has been a desire to further improve their quietness and low vibration. To improve the quietness and low vibration of scroll compressors, it is necessary to further reduce the overall imbalance of the moving system components, including the drive shaft and parts fixed or connected to it.

[0009] Therefore, the purpose of this disclosure is to provide a scroll compressor capable of reducing the overall imbalance of movable system components, including a drive shaft and components fixed or connected to the drive shaft.

[0010] Technical solutions adopted to solve technical problems

[0011] The inventors conducted in-depth research and experiments, and discovered that by appropriately arranging multiple balancers, the overall imbalance of the movable system components, including the drive shaft and parts fixed or connected to the drive shaft, can be further reduced. This invention is based on this insight.

[0012] According to one aspect of the present invention, a scroll compressor includes: a fixed scroll having a fixed base plate and a fixed scroll wall erected on the fixed base plate; a rotating scroll having a rotating base plate, a rotating scroll wall erected on one side of the rotating base plate and engaging with the fixed scroll wall, and a cylindrical portion erected on the other side of the rotating base plate; a compression chamber formed between the fixed scroll and the rotating scroll; and a drive force transmission mechanism having a drive shaft that is driven to rotate, an eccentric pin provided at one end of the drive shaft, and an eccentric bushing rotatably mounted on the eccentric pin and rotatably inserted into the inner side of the cylindrical portion via a bearing, the drive force transmission mechanism transmitting a drive force to the rotating scroll. The scroll compressor mechanism compresses fluid drawn into the compression chamber by causing the rotating scroll to revolve relative to the fixed scroll using the drive force, thereby changing the volume of the compression chamber. Furthermore, the aforementioned scroll compressor includes: a shaft balancer integrally formed with the drive shaft and having a first counterweight portion sandwiching the centerline of the drive shaft on the opposite side from the eccentric pin; and a bushing balancer integrally formed with the eccentric bushing and having a second counterweight portion located radially outside the eccentric bushing and sandwiching the centerline of the eccentric bushing on the opposite side from the centerline of the eccentric pin. When viewed axially from the drive shaft, the second counterweight portion is symmetrically formed with respect to an imaginary straight line passing through the center of the drive shaft and the center of the eccentric bushing, while the first counterweight portion is asymmetrically formed with respect to the imaginary straight line.

[0013] Invention Effects

[0014] According to one aspect of this invention, a scroll compressor capable of reducing the overall imbalance of movable system components, including a drive shaft and components fixed or connected to the drive shaft, can be provided. Attached Figure Description

[0015] Figure 1 This is a cross-sectional view illustrating the schematic structure of a scroll compressor according to an embodiment.

[0016] Figure 2 yes Figure 1 The enlarged view of the main parts shows the crank mechanism and the rotation-stopping mechanism.

[0017] Figure 3 It is a perspective view showing the configuration of the shaft balancer, bushing balancer, first rotor balancer, and second rotor balancer.

[0018] Figure 4 It mainly shows the exploded perspective view of the shaft balancer and bushing balancer.

[0019] Figure 5 This is a diagram showing the state of the shaft balancer and bushing balancer, viewed from the axial direction of the drive shaft.

[0020] Figure 6 It shows from and Figure 5 A diagram showing the state of the shaft balancer and bushing balancer from the opposite side. Detailed Implementation

[0021] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0022] Figure 1 This is a cross-sectional view illustrating the schematic structure of a scroll compressor according to an embodiment of the present invention. The scroll compressor 10 of this embodiment is, for example, assembled in the refrigerant circuit of an automotive air conditioning system, configured to receive low-pressure gaseous refrigerant (fluid) from the refrigerant circuit, compress it, pressurize it, and return it to the refrigerant circuit. Furthermore, Figure 1 The left side of the image shows the front of the scroll compressor 10. Figure 1 The right side of the image shows the rear side of the scroll compressor 10. Figure 1 The upper part of the middle is the upper part of the scroll compressor 10. Figure 1 The lower part of the middle is the lower part of the scroll compressor 10. Additionally, Figure 1 The paper in the middle, near the front, is on the left side of the scroll compressor 10. Figure 1 The right side of the paper's depth is the right side of the scroll compressor 10.

[0023] The scroll compressor 10 includes: a housing 20; a drive shaft 30; an electric motor 40 that drives the drive shaft 30 to rotate; a scroll unit 50 that drives and compresses (low-pressure) gaseous refrigerant via the drive shaft 30; and an inverter 60 that drives and controls the electric motor 40. The drive shaft 30, the electric motor 40, the scroll unit 50, and the inverter 60 are housed within the housing 20. Furthermore, the scroll unit 50 includes a fixed scroll 51 and a rotating scroll 52 that revolves around the fixed scroll 51.

[0024] The housing 20 includes a front housing 21, a cover member 22, a middle housing 23, and a rear housing 24. Moreover, they are fastened together by fasteners (not shown) and constitute the housing 20 of the scroll compressor 10.

[0025] The front housing 21 has a cylindrical peripheral wall portion (hereinafter referred to as the "first peripheral wall portion") 211 extending front to back and a partition portion (hereinafter referred to as the "first partition portion") 212 that separates the interior of the first peripheral wall portion 211 from the front to the back. The front end face of the first peripheral wall portion 211 constitutes the front end face of the front housing 21, and the rear end face of the first peripheral wall portion 211 constitutes the rear end face of the front housing 21. The interior of the first peripheral wall portion 211 (i.e., the interior space of the front housing 21) is divided by the first partition portion 212 into an inverter housing space on the front side that houses the inverter 60 and a motor housing space on the rear side that houses the motor 40. That is, the motor 40 and the inverter 60 are housed in the front housing 21.

[0026] A support portion 213 is provided on the first partition 212 to support the front end of the drive shaft 30. The support portion 213 is formed to protrude cylindrically from the rear side of the first partition 212 toward the motor housing space, and is configured to rotatably support the front end of the drive shaft 30 via a first bearing 214 installed inside.

[0027] A cover member 22 is joined to the front end face of the front housing 21, thereby enclosing the inverter housing space (forming an inverter housing chamber). The front end face of the intermediate housing 23 is joined to the rear end face of the front housing 21. In addition, sealing members can be arranged between the front housing 21 and the cover member 22 and between the front housing 21 and the intermediate housing 23 as needed.

[0028] The intermediate outer shell 23 has a cylindrical peripheral wall portion (hereinafter referred to as the "second peripheral wall portion") 231 extending front to back and a partition portion (hereinafter referred to as the "second partition portion") 232 that separates the interior of the second peripheral wall portion 231 from the front to the back. The front end face of the second peripheral wall portion 231 constitutes the front end face of the intermediate outer shell 23, and the rear end face of the second peripheral wall portion 231 constitutes the rear end face of the intermediate outer shell 23. The interior of the second peripheral wall portion 231 (i.e., the interior space of the intermediate outer shell 23) is divided by the second partition portion 232 into a front connecting space that connects to the aforementioned motor housing space of the front outer shell 21 and a rear scroll housing space that houses the scroll unit 50. That is, the scroll unit 50 is housed in the intermediate outer shell 23.

[0029] The second partition 232 has a hollow protrusion 233 that protrudes towards the front housing 21 (motor housing space). The hollow protrusion 233 is disposed radially at the center of the second partition 232, opposite to the support portion 213 disposed on the first partition 212 of the front housing 21. A shaft insertion hole 234 is formed at the top of the hollow protrusion 233, which communicates the inside and outside of the hollow protrusion 233 and allows the drive shaft 30 to pass through. A second bearing 235 that rotatably supports the rear end portion of the drive shaft 30 is installed inside the hollow protrusion 233. That is, in this embodiment, the drive shaft 30 extends in the front-rear direction within the housing 20 and is rotatably supported by a first bearing 214 disposed on the front housing 21 side and a second bearing 235 disposed on the intermediate housing 23 side.

[0030] The rear end face of the rear end face of the intermediate outer shell 23 is joined to the rear end face of the intermediate outer shell 23. In this embodiment, a recess 236 is formed on the rear end face of the intermediate outer shell 23, i.e., the rear end face of the second peripheral wall portion 231, to receive the outer edge of the fixing base plate 511 (described later) constituting the fixed scroll 51 of the scroll unit 50. Furthermore, the outer edge of the fixing base plate 511 is received in the recess 236 and is held between the intermediate outer shell 23 and the rear end face 24. Thus, the fixed scroll 51 is fixed, and the opening on the rear side of the second peripheral wall portion 231 is closed by the fixing base plate 511 of the fixed scroll 51. Additionally, a sealing member can be disposed between the intermediate outer shell 23 and the rear end face 24 as needed.

[0031] The rear outer shell 24 is formed into a bottomed cylindrical shape, having a cylindrical peripheral wall portion (hereinafter referred to as "third peripheral wall portion") 241 extending from front to back and a bottom wall portion 242 that closes the opening on the rear side of the third peripheral wall portion 241. Moreover, the front end face of the third peripheral wall portion 241, which constitutes the front end face of the rear outer shell 24, is joined to the rear end face of the second peripheral wall portion 231, which is the rear end face of the intermediate outer shell 23, thereby closing the opening on the front side of the third peripheral wall portion 241 by the fixing base plate 511 of the fixing volute 51.

[0032] The motor 40 is, for example, a three-phase AC motor, including a stator core unit 41 and a rotor 42.

[0033] The stator core unit 41 is fixed to the inner peripheral surface of the first peripheral wall portion 211 of the front housing 21. Direct current from a vehicle battery (not shown) or the like is converted into alternating current by the inverter 60 and supplied to the stator core unit 41.

[0034] The rotor 42 is configured with a predetermined gap to the radially inner side of the stator core unit 41. A permanent magnet is installed in the rotor 42. The rotor 42 is formed into a cylindrical shape and is fixed to the drive shaft 30 with the drive shaft 30 inserted through its hollow portion. That is, the rotor 42 is integrated with the drive shaft 30 and rotates integrally with the drive shaft 30.

[0035] When the motor 40 generates a magnetic field in the stator core unit 41 through the power supply from the inverter 60, the rotational force will act on the aforementioned permanent magnet of the rotor 42 to make the rotor 42 rotate, thereby causing the drive shaft 30 to rotate (rotation drive).

[0036] As described above, the scroll unit 50 includes a fixed scroll 51 and a rotating scroll 52 that revolves around the fixed scroll 51.

[0037] The fixed scroll 51 has a circular plate-shaped fixed base plate 511 and a fixed scroll wall 512 erected on one side of the fixed base plate 511. The fixed scroll wall 512 extends in a scroll shape (involute curve shape) from the inner end (winding start portion) on the radially inward side to the outer end (winding end portion) on the aforementioned one side of the fixed base plate 511. The fixed scroll 51 is fixed by being clamped by the intermediate outer shell 23 and the rear outer shell 24 with the aforementioned one side of the fixed base plate 511 (the side where the fixed scroll wall 512 is erected) facing forward and the outer edge of the fixed base plate 511 being received in the recess 236.

[0038] The swirling scroll 52 has a circular plate-shaped swirling base plate 521, a swirling scroll wall 522 erected on one side of the swirling base plate 521, and a cylindrical portion 523 protruding from the other side of the swirling base plate 521. The swirling scroll wall 522 extends radially inward from the inner end (winding start portion) along a scroll shape (involute curve shape) to the outer end (winding end portion) on the aforementioned one side of the swirling base plate 521. The swirling scroll 52 is arranged such that the swirling scroll wall 522 engages with the fixed scroll wall 512 of the fixed scroll 51. That is, the swirling scroll 52 is arranged between the second partition portion 232 of the intermediate housing 23 and the fixed scroll 51 with the aforementioned one side of the swirling base plate 521 (the side where the swirling scroll wall 522 is erected) facing rearward. Alternatively, the aforementioned other side of the swirling base plate 521 may be referred to as the back side of the swirling base plate 521.

[0039] The rotary scroll 52 is driven by a driving force transmitted via the drive shaft 30 and the crank mechanism 70. The driven rotary scroll 52 is configured to revolve around the fixed scroll 51 while its rotation is prevented by the rotation-stopping mechanism 80; in other words, it revolves around the axis of the fixed scroll 51. Therefore, in this embodiment, the drive shaft 30 and the crank mechanism 70 constitute the "driving force transmission mechanism" of the present invention.

[0040] The scroll unit 50 is configured to draw in and compress low-pressure gaseous refrigerant by causing the rotating scroll 52 to revolve relative to the fixed scroll 51. Furthermore, an annular thrust plate 90 is disposed between the rotating base plate 521 of the rotating scroll 52 and the second partition wall portion 232 of the intermediate housing 23, and the rear surface of the second partition wall portion 232 receives thrust from the rotating scroll 52 via the thrust plate 90.

[0041] Figure 2 yes Figure 1 The enlarged view of the main parts mainly shows the crank mechanism 70 and the rotation-stopping mechanism 80.

[0042] The crank mechanism 70 is configured to connect the drive shaft 30 to the rotary scroll 52, and to convert the rotary motion of the drive shaft 30 into the rotary motion of the rotary scroll 52. For example... Figure 2 As shown, the crank mechanism 70 includes an eccentric pin 71 disposed at the rear end of the drive shaft 30 and an eccentric bushing 72 mounted on the eccentric pin 71.

[0043] An eccentric pin 71 extends axially from the rear end face of the drive shaft 30. Furthermore, the eccentric pin 71 is eccentric relative to the drive shaft 30. That is, the centerline CL1 of the eccentric pin 71 is offset from the centerline CL0 of the drive shaft 30.

[0044] An eccentric bushing 72 is rotatably mounted on an eccentric pin 71 and is rotatably inserted into the inner side of the cylindrical portion 523 of the swivel disk 52 via a bearing 73. Specifically, the eccentric bushing 72 is cylindrical. Furthermore, a pin insertion hole 72a is formed in the eccentric bushing 72 through which the eccentric pin 71 rotatably inserts. The pin insertion hole 72a is formed at a position eccentric to the center line CL2 of the eccentric bushing 72 and extends axially through the eccentric bushing 72. Moreover, the eccentric bushing 72 is rotatably mounted on the eccentric pin 71 by inserting the eccentric pin 71 through the pin insertion hole 72a. Therefore, the center line of the pin insertion hole 72a coincides with the center line CL1 of the eccentric pin 71. In addition, the eccentric bushing 72 is inserted into the inner side of the cylindrical portion 523 of the rotary scroll 52 by supporting its outer peripheral surface 72b on a bearing 73 mounted inside the cylindrical portion 523 of the rotary scroll 52 in a rotatable manner via the bearing 73.

[0045] The rotation-stopping mechanism 80 is configured as a pin-ring type rotation-stopping mechanism, including multiple rotation-stopping parts 81. For example... Figure 2As shown, the rotation-stopping part 81 of the rotation-stopping mechanism 80 is composed of a ring 82 and a pin 83. The ring 82 is pressed into a circular hole formed on the other side (back side) of the rotary base plate 521. The pin 83 is fixed to the second partition wall 232 of the intermediate housing 23 and extends through the thrust plate 90 to the inner side of the ring 82. In this embodiment, six circular holes are formed at equal intervals on the other side (back side) of the rotary base plate 521 in a manner surrounding the cylindrical part 523, and a ring 82 is pressed into each circular hole (see reference). Figure 3 Additionally, six pins 83 corresponding to the six rings 82 are fixed to the second partition 232 of the intermediate outer shell 23. That is, in this embodiment, the rotation-stopping mechanism 80 has six rotation-stopping parts 81 arranged at equal intervals along the circumference. However, it is not limited to this. As long as there are three or more rotation-stopping parts 81, the number of rotation-stopping parts 81 can be arbitrarily set.

[0046] return Figure 1 The scroll compressor 10 includes: an intake chamber H1 into which a low-pressure gaseous refrigerant flows; a compression chamber H2 into which the low-pressure gaseous refrigerant is compressed; a discharge chamber H3 into which the gaseous refrigerant compressed in the compression chamber H2 is discharged; a gas-liquid separation chamber H4 into which lubricating oil is separated from the gaseous refrigerant compressed in the compression chamber H2; and a back pressure chamber H5 disposed on the other side (back side) of the swivel base plate 521 of the swivel scroll 52.

[0047] The suction chamber H1 is formed by dividing the first peripheral wall portion 211 of the front outer shell 21, the first partition wall portion 212 of the front outer shell 21, the first peripheral wall portion 231 of the intermediate outer shell 23, and the second partition wall portion 232 of the intermediate outer shell 23. That is, in this embodiment, the suction chamber H1 is formed by the motor housing space of the front outer shell 21 and the connection space of the intermediate outer shell 23. An intake port P1 is formed in the first peripheral wall portion 211. The intake port P1 is connected to the refrigerant circuit (low-pressure side) via a connecting pipe (not shown) or the like. Therefore, low-pressure refrigerant from the refrigerant return flows into the suction chamber H1 through the intake port P1. In addition, a refrigerant passage L1 is formed in the intermediate outer shell 23 for guiding the low-pressure gaseous refrigerant in the suction chamber H1 to the space H6 near the outer end of the scroll unit 50.

[0048] Compression chamber H2 is formed between fixed scroll plate 51 and rotating scroll plate 52. Specifically, in scroll plate unit 50, when rotating scroll plate 52 revolves relative to fixed scroll plate 51, rotating scroll wall 522 contacts fixed scroll wall 512, forming a crescent-shaped sealed space radially outward through fixed base plate 511, fixed scroll wall 512, rotating base plate 521, and rotating scroll wall 522. The formed crescent-shaped sealed space moves radially inward while gradually decreasing in volume. The crescent-shaped sealed space formed between fixed scroll plate 51 and rotating scroll plate 52 constitutes compression chamber H2. Scroll plate unit 50 is configured to compress low-pressure gaseous refrigerant by drawing in low-pressure gaseous refrigerant from space H6 when forming the aforementioned crescent-shaped sealed space (i.e., compression chamber H2).

[0049] The discharge chamber H3 is formed by dividing the third peripheral wall portion 241 of the rear outer casing 24, the bottom wall portion 242 of the rear outer casing 24, and the fixing base plate 511 of the fixed scroll 51. That is, the interior of the third peripheral wall portion 241 of the rear outer casing 24 constitutes the discharge chamber H3. A discharge hole L2 is formed at the radial center of the fixing base plate 511 of the fixed scroll 51, which communicates with the innermost compression chamber H2 and the discharge chamber H3. Therefore, the gaseous refrigerant compressed in the compression chamber H2 of the scroll unit 50 is discharged to the discharge chamber H3 through the discharge hole L2. In addition, a check valve (reed valve) 95 is installed on the discharge hole L2, which allows the gaseous refrigerant to flow from the compression chamber H2 to the discharge chamber H3, but restricts the gaseous refrigerant from the discharge chamber H3 to the compression chamber H2.

[0050] A gas-liquid separation chamber H4 is disposed in the rear outer casing 24. Specifically, in this embodiment, the gas-liquid separation chamber H4 is formed as a cylindrical space extending downward from the outer peripheral surface toward the interior within the bottom wall portion 242 of the rear outer casing 24. The discharge chamber H3 and the gas-liquid separation chamber H4 are connected via a connecting hole L3. An oil separator 100 for separating lubricating oil contained in the gaseous refrigerant is disposed in the gas-liquid separation chamber H4. A centrifugal oil separator is used here, but it is not limited to this, and other types of oil separators may also be used. An outlet P2 is provided at the upper part of the oil separator 100 in the gas-liquid separation chamber H4. The outlet P2 is connected to the refrigerant circuit (high-pressure side) via a connecting pipe (not shown) or the like.

[0051] A back pressure chamber H5 is formed between the gyratory base plate 521 of the gyratory scroll 52 and the second partition wall portion 232 of the intermediate outer shell 23. In this embodiment, the back pressure chamber H5 includes the internal space of the hollow protrusion 233 of the second partition wall portion 232. A lubricating oil passage L4 is formed on the intermediate outer shell 23 and the rear outer shell 24, which connects the discharge chamber H3 to the back pressure chamber H5 and the gas-liquid separation chamber H4 to the back pressure chamber H5. A throttling orifice (throttling section) OL is disposed in the middle of the lubricating oil passage L4. In addition, the back pressure chamber H5 communicates with the suction chamber H1 through a small gap between the inner peripheral surface of the shaft insertion hole 234 and the outer peripheral surface of the drive shaft 30. However, it is not limited to this. The back pressure chamber H5 may also be configured to communicate with the suction chamber H1 through a pressure relief passage in which a throttling orifice or a back pressure control valve is provided in the middle.

[0052] Here, the operation of the scroll compressor 10 is briefly explained.

[0053] When the drive shaft 30 is rotated by the motor 40 powered by the inverter 60, the rotation of the drive shaft 30 is transmitted to the rotary scroll 52 via the crank mechanism 70, and the rotary scroll 52 revolves relative to the fixed scroll 51. Thus, low-pressure gaseous refrigerant from the aforementioned refrigerant circuit flows into the suction chamber H1 through the suction port P1, passes through the refrigerant passage L1 and reaches the space H6, and is then drawn into the compression chamber H2 formed between the fixed scroll 51 and the rotary scroll 52 and compressed. The compressed gaseous refrigerant (high-pressure gaseous refrigerant) in the compression chamber H2 is discharged into the discharge chamber H3 through the discharge port L2 (and check valve 90), and then flows into the gas-liquid separation chamber H4 through the connecting port L3. The gaseous refrigerant flowing into the gas-liquid separation chamber H4 is separated from the lubricating oil contained therein by the oil separator 100. Then, the gaseous refrigerant from which the lubricating oil has been separated by the oil separator 100 is discharged from the discharge port P2 back to the aforementioned refrigerant circuit. On the other hand, the lubricating oil separated from the gaseous refrigerant by the oil separator 100 is stored at the bottom of the gas-liquid separation chamber H4. In addition, a portion of the lubricating oil contained in the gaseous refrigerant discharged into the discharge chamber H3 is stored at the bottom of the discharge chamber H3.

[0054] The back pressure chamber H5 is connected to the discharge chamber H3 and the gas-liquid separation chamber H4 via the lubricating oil passage L4, and is also connected to the suction chamber H1 via a small gap between the inner circumferential surface of the shaft insertion hole 234 and the outer circumferential surface of the drive shaft 30. Therefore, lubricating oil stored at the bottom of the discharge chamber H3 and / or the bottom of the gas-liquid separation chamber H4 is supplied to the back pressure chamber H5 via the lubricating oil passage L4, but at this time, the pressure is reduced by the throttling orifice OL. Furthermore, the back pressure chamber H5 is connected to the suction chamber H1 via the aforementioned small gap, restricting the flow of lubricating oil (and / or gaseous refrigerant) from the back pressure chamber H5 to the suction chamber H1. Therefore, the pressure in the back pressure chamber H5 is maintained at an intermediate pressure Pm between the pressure Ps in the suction chamber H1 and the pressure Pd in ​​the discharge chamber H3 (= the pressure in the gas-liquid separation chamber H4). Then, this intermediate pressure Pm presses the vortex disk 52 towards the fixed vortex disk 51. That is, the back pressure chamber H5 causes the pressure (back pressure) Pm pressing towards the fixed scroll 51 to act on the rotating scroll 52.

[0055] Next, the structure of the scroll compressor 10 that achieves overall balance of the movable system components, including the drive shaft 30 and the components fixed or connected to the drive shaft 30, and appropriately maintains the pressing force of the swirling scroll wall 522 relative to the fixed scroll wall 512 will be described.

[0056] The scroll compressor 10 has this structure primarily to suppress noise generated by the vibration of the first bearing 214 and the second bearing 235 supporting the drive shaft 30, thereby preventing increased pressure on the swirling scroll wall 522 relative to the fixed scroll wall 512, increased wear on the fixed scroll wall 512 and / or the swirling scroll wall 522, or damage to the fixed scroll wall 512 and / or the swirling scroll wall 522. Furthermore, in this embodiment, the drive shaft 30, the rotor 42 fixed to the drive shaft 30, the eccentric bushing 72 mounted on the eccentric pin 71 of the drive shaft 30, and the swirling scroll 52 with the bearing 73 mounted on the cylindrical portion 523 are essentially the movable system components described above.

[0057] Reference Figure 1 and Figure 2 As a structure for obtaining the overall balance of the movable parts and properly maintaining the pressing force of the swirling scroll wall 522 relative to the fixed scroll wall 512, the scroll compressor 10 has: a balancer (hereinafter referred to as "shaft balancer") 31 integrally provided with the drive shaft 30; a balancer (hereinafter referred to as "shoulder balancer") 721 integrally provided with the eccentric bushing 72; and two balancers (hereinafter referred to as "first rotor balancer 421" and "second rotor balancer 422") integrally provided with the rotor 42.

[0058] Figure 3This is a perspective view showing the configuration of the shaft balancer 31, the first rotor balancer 421, the second rotor balancer 422, and the bushing balancer 721. Figure 4 This is an exploded perspective view mainly showing the shaft balancer 31 and the bushing balancer 721. Additionally, Figure 5 This is a diagram showing the state of the shaft balancer 31 and the bushing balancer 721, etc., viewed from the axial direction (in this case, the front) of the drive shaft 30. Figure 6 It shows from and Figure 5 A diagram showing the state of the shaft balancer 31 and the bushing balancer 721, etc., viewed from the opposite side (rear side in this case). Furthermore, in the following description, the dimension in the front-to-back direction, in other words, the dimension along the axial direction of the drive shaft 30, will be referred to as "thickness," and the dimension in the left-to-right direction will be referred to as "width."

[0059] The shaft balancer 31 is fixed to the outer peripheral surface near the rear end of the drive shaft 30 (i.e., near the end on the side of the eccentric pin 71) and rotates integrally with the drive shaft 30. In this embodiment, the shaft balancer 31 is disposed in the back pressure chamber H5. The shaft balancer 31 has: an annular mounting portion (hereinafter referred to as "first mounting portion") 32 that is externally fitted and fixed to the outer peripheral surface of the drive shaft 30; a counterweight portion (hereinafter referred to as "first counterweight portion") 33 that is separated from the first mounting portion 32 on the side opposite to the eccentric pin 71, sandwiching the center line CL0 of the drive shaft 30; and a connecting portion (hereinafter referred to as "first connecting portion") 34 that connects the first mounting portion 32 and the first counterweight portion 33. In addition, in this embodiment, the shaft balancer 31 is formed with a certain thickness, and the first connecting portion 34 is formed to be narrower than the first counterweight portion 33.

[0060] Reference Figure 5 and Figure 6 When the shaft balancer 31 is viewed axially from the drive shaft 30, the shaft balancer 31 is asymmetrically formed with respect to an imaginary straight line VL passing through the center (centerline CL0) of the drive shaft 30 and the center (centerline CL2) of the eccentric bushing 72. Furthermore, the first counterweight portion 33 of the shaft balancer 31 is asymmetrically formed with respect to the imaginary straight line VL (the first mounting portion 32 and the first connecting portion 34 are symmetrically formed with respect to the imaginary straight line VL). Specifically, the first counterweight portion 33 is formed such that its mass (or weight) is greater than that of the second portion 3b located opposite the center (centerline CL1) of the eccentric pin 71 relative to the imaginary straight line VL, which is located on the same side as the center (centerline CL1) of the eccentric pin 71 relative to the imaginary straight line VL. In this embodiment, as described above, since the shaft balancer 31 is formed with a certain thickness, the second portion 33b of the first counterweight portion 33 is formed to be larger in the width direction than the first portion 33a of the first counterweight portion 33. Figure 5 and Figure 6 The amount shown in the shaded area.

[0061] The bushing balancer 721 is fixed to the outer peripheral surface near the front end of the eccentric bushing 72 (i.e., near the end on the drive shaft 30 side) and rotates or oscillates integrally with the eccentric bushing 72. Additionally, Figure 4 , Figure 6 Reference numeral 74 in the figure indicates a retaining ring for securing the eccentric bushing 72 mounted on the eccentric pin 71. The bushing balancer 721 is similarly disposed in the back pressure chamber H5 as the shaft balancer 31. The bushing balancer 721 includes: an annular mounting portion (hereinafter referred to as the "second mounting portion") 722 that is externally fitted and fixed to the outer peripheral surface 72b of the eccentric bushing 72; a counterweight portion (hereinafter referred to as the "second counterweight portion") 723 that is radially outside the second mounting portion 722 (in other words, the eccentric bushing 72) and separate from the second mounting portion 722 (eccentric bushing 72); and a connecting portion (hereinafter referred to as the "second connecting portion") 724 that connects the second mounting portion 722 and the second counterweight portion 723. Furthermore, in this embodiment, the bushing balancer 721 is formed to have a mass (or weight) greater than that of the shaft balancer 31.

[0062] The second counterweight 723, clamping the center line CL2 of the eccentric bushing 72 and the center line CL0 of the drive shaft 30, is positioned on the opposite side of the center line CL1 (= the center line of the pin insertion hole 72a) of the eccentric pin 71. The second counterweight 723 is formed as a block, while the second connecting portion 724 is formed as a plate. In other words, the second counterweight 723 is formed with a thicker wall than the second connecting portion 724.

[0063] Reference Figure 5 and Figure 6 When the bushing balancer 721 is viewed axially from the drive shaft 30, the second counterweight 723 and the second connecting portion 724 are generally formed in a semi-circular shape. However, this is not a limitation. When the bushing balancer 721 is viewed axially from the drive shaft 30, the second counterweight 723 and the second connecting portion 724 may also be generally formed in a fan shape. In addition, the bushing balancer 721 is formed symmetrically with respect to an imaginary straight line VL.

[0064] The second counterweight 723 includes: an arc-shaped rear protrusion 723a protruding rearward (i.e., to the side of the vortex disk 52) relative to the second connecting portion 724; and a pair of arc-shaped front protrusions 723b, 723b protruding forward (i.e., to the side of the shaft balancer 31) relative to the second connecting portion 724. The pair of front protrusions 723b, 723b are each smaller than the rear protrusion 723a. The pair of front protrusions 723b, 723b are separated from each other and are arranged symmetrically with respect to an imaginary straight line VL. Furthermore, in this embodiment, a portion of the first mounting portion 32 of the shaft balancer 31 and the first connecting portion 34 (see reference 34) are disposed between the pair of front protrusions 723b, 723b of the bushing balancer 721. Figure 5 That is, the distance D1 from the center line CL0 of the drive shaft 30 to the front end of the first counterweight 33 in the shaft balancer 31 is greater than the distance D2 from the center line CL0 of the drive shaft 30 to the front end of the second counterweight 723 in the bushing balancer 721.

[0065] The first rotor balancer 421 is fixed to the rear end face of the rotor 42, in other words, fixed to the end face of the shaft balancer 31 side of the rotor 42, and rotates integrally with the rotor 42 (i.e., the drive shaft 30). The first rotor balancer 421 is formed in an arc shape and, like the first counterweight 33 of the shaft balancer 31, is positioned on the opposite side of the center line CL0 of the drive shaft 30. That is, the first rotor balancer 421 is arranged opposite to the first counterweight 33 of the shaft balancer 31.

[0066] The second rotor balancer 422 is fixed to the front end face of the rotor 42, in other words, fixed to the side of the rotor 42 opposite to the side of the vortex disk 52, and rotates integrally with the rotor 42 (i.e., the drive shaft 30). The second rotor balancer 422 is formed in an arc shape and is located on the same side as the center line CL0 of the drive shaft 30 and the eccentric pin 71.

[0067] The scroll compressor 10 according to the embodiment can achieve the following effects.

[0068] The scroll compressor 10 has a bushing balancer 721 integrally formed with the eccentric bushing 72. In addition, the bushing balancer 721 has a second counterweight 723, which is located radially outside the eccentric bushing 72 and sandwiches the center line CL2 of the eccentric bushing 72 on the opposite side to the center line CL1 of the eccentric pin 71 (pin insertion hole 72a).

[0069] The vortex wall 52 revolves, generating centrifugal force. However, this centrifugal force is counteracted by the centrifugal force of the bushing balancer 721. Therefore, the pressing force between the vortex wall 522 and the fixed vortex wall 512 can be appropriately maintained. This prevents increased wear or breakage of the fixed vortex wall 512 and / or the vortex wall 522. Furthermore, it ensures a good seal (tightness) of the compression chamber H2 formed between the fixed vortex wall 51 and the vortex wall 52.

[0070] In addition to the bushing balancer 721, the scroll compressor 10 also has a shaft balancer 31 integrally formed with the drive shaft 30. The second counterweight 723 of the bushing balancer 721 is positioned on the opposite side of the centerline CL2 of the eccentric bushing 72 and the centerline CL1 of the eccentric pin 71. Furthermore, it is positioned on the opposite side of the centerline CL0 of the drive shaft 30. The shaft balancer 31 also has a first counterweight 33 positioned on the opposite side of the eccentric pin 71 and the centerline CL0 of the drive shaft 30. Moreover, when the shaft balancer 31 and the bushing balancer 721 are viewed axially from the drive shaft 30, the second counterweight 723 is symmetrically formed with respect to an imaginary straight line VL passing through the centerline CL0 of the drive shaft 30 and the centerline CL2 of the eccentric bushing 72, while the first counterweight 33 is asymmetrically formed with respect to the imaginary straight line VL. Specifically, the first counterweight 33 of the shaft balancer 31 is configured such that the mass (or weight) of the second part 33b, which is located on the opposite side of the center of the eccentric pin 71 (centerline CL1) relative to the imaginary straight line VL, is greater than that of the first part 33a, which is located on the same side as the center of the eccentric pin 71 (centerline CL1) relative to the imaginary straight line VL.

[0071] Therefore, for the entire movable system component including the drive shaft 30 and the parts fixed or connected to the drive shaft 30, balance in the direction of the imaginary straight line VL (i.e., the vertical direction) can be obtained by the shaft balancer 31 and the bushing balancer 721, and balance in the direction of the left and right directions (i.e., the direction passing through the center of the drive shaft 30 and orthogonal to the imaginary straight line VL) can be obtained mainly by the shaft balancer 31. Therefore, vibration of the first bearing 214 and the second bearing 235 supporting the drive shaft 30 can be suppressed, and in particular, quietness and low vibration in the high-rotation region can be improved.

[0072] Here, when viewing the shaft balancer 31 and bushing balancer 721 axially from the drive shaft 30, the second counterweight portion 723 of the bushing balancer 721 includes a pair of front protrusions 723b, 723b that protrude toward the shaft balancer 31 and are separated from each other by an imaginary straight line VL. A first connecting portion 34 of the shaft balancer 31 is disposed between the pair of front protrusions 723b, 723b. Therefore, the first connecting portion 34 of the shaft balancer 31 functions as a stopper that limits the rotational range (or oscillation range) of the bushing balancer 721 (eccentric bushing 72), preventing the eccentric bushing 72 and the bushing balancer 721 from excessively rotating (oscillating) due to inertia, etc. Alternatively, the space for arranging the shaft balancer 31 and bushing balancer 721 can be reduced axially along the drive shaft 30.

[0073] Furthermore, the scroll compressor 10 includes: a first rotor balancer 421, which is fixed to the end face (rear end face) of the rotor 42 on the side of the shaft balancer 31 and is positioned on the opposite side of the eccentric pin 71 relative to the center line CL0 of the drive shaft 30; and a second rotor balancer 422, which is fixed to the end face (front end face) of the rotor 42 on the opposite side of the shaft balancer 31 and is positioned on the same side of the eccentric pin 71 relative to the center line CL0 of the drive shaft 30.

[0074] Therefore, for the entire movable system component including the drive shaft 30 and the parts fixed or connected to the drive shaft 30, it is possible to achieve balance in the longitudinal direction along the axial direction of the drive shaft 30 while adjusting the balance in the vertical direction along the imaginary straight line VL with higher precision. Thus, the vibration of the first bearing 214 and the second bearing 235 supporting the drive shaft 30 can be effectively suppressed, further improving the quietness and low vibration of the scroll compressor 10.

[0075] Furthermore, in the above embodiment, the second portion 33b of the first counterweight portion 33 of the shaft balancer 31 is formed to be larger in the width direction than the first portion 33a of the first counterweight portion 33. However, this is not a limitation. For example, part or all of the second portion 33b may be formed to be thicker than the first portion 33a.

[0076] Furthermore, in the above embodiment, the bushing balancer 721 is formed separately from the eccentric bushing 72 and fixed to the outer peripheral surface of the eccentric bushing 72. However, this is not a limitation. The eccentric bushing 72 and the bushing balancer 721 can also be integrally formed. That is, the eccentric bushing 72 and the bushing balancer 721 can also be formed as a single component (eccentric bushing with balancer).

[0077] Furthermore, in the above embodiment, the first counterweight portion 33 and the first connecting portion 34 of the shaft balancer 31 are separated, but the first counterweight portion 33 and the first connecting portion 34 may also be considered as the counterweight portion of the shaft balancer 31. Similarly, in the above embodiment, the second counterweight portion 723 and the second connecting portion 724 of the bushing balancer 721 are separated, but the second counterweight portion 723 and the second connecting portion 724 may also be considered as the counterweight portion of the bushing balancer 721.

[0078] While the embodiments and variations of the present invention have been described above, the present invention is not limited to the above embodiments and variations, and further modifications and changes can be made based on the technical concept of the present invention.

[0079] Symbol Explanation

[0080] 10…Scroll compressor, 30…Drive shaft (drive force transmission mechanism), 31…Shaft balancer, 32…First mounting part, 33…First counterweight part, 34…First connecting part, 40…Motor, 41…Stator core unit, 42…Rotor, 51…Fixed scroll, 52…Rotating scroll, 71…Eccentric pin (drive force transmission mechanism), 72…Eccentric bushing (drive force transmission mechanism), 73…Bearing, 421…First rotor balancer, 422…Second rotor balancer, 511…Fixed base plate, 512… Fixed vortex wall, 521…rotating base plate, 522…rotating vortex wall, 523…cylindrical part, 721…shoulder balancer, 722…second mounting part, 723…second counterweight part, 723a…rear protrusion, 723b…front protrusion (protrusion), CL0…centerline of drive shaft, CL1…centerline of eccentric pin, CL2…centerline of eccentric bushing, H1…inhalation chamber, H2…compression chamber, H3…exhaust chamber, H4…gas-liquid separation chamber, H5…back pressure chamber, L2…exhaust hole, VL…imaginary straight line.

Claims

1. A scroll compressor, The scroll compressor includes: A fixed vortex disk, the fixed vortex disk having a fixed base plate and a fixed vortex wall erected on the fixed base plate; A swirling scroll, comprising a swirling base plate, a swirling scroll wall erected on one side of the swirling base plate and meshing with a fixed scroll wall, and a cylindrical portion erected on the other side of the swirling base plate; a compression chamber formed between the fixed scroll and the swirling scroll; and a driving force transmission mechanism, comprising a driven shaft that is driven to rotate, an eccentric pin disposed at one end of the drive shaft, and an eccentric bushing rotatably mounted on the eccentric pin and rotatably inserted into the inner side of the cylindrical portion via a bearing, the driving force transmission mechanism transmitting driving force to the swirling scroll, the scroll compression mechanism being configured to compress the contents of the swirling scroll by using the driving force to cause the swirling scroll to revolve and rotate relative to the fixed scroll. The volume change of the compression chamber thereby compresses the fluid drawn into the compression chamber. The scroll compressor includes: a shaft balancer integrally disposed with the drive shaft and having a first counterweight portion sandwiching the centerline of the drive shaft on the opposite side of the eccentric pin; and a bushing balancer integrally disposed with the eccentric bushing and having a second counterweight portion located radially outside the eccentric bushing and sandwiching the centerline of the eccentric bushing on the opposite side of the centerline of the eccentric pin. When viewed axially from the drive shaft, the second counterweight portion is symmetrically formed with respect to an imaginary straight line passing through the center of the drive shaft and the center of the eccentric bushing, while the first counterweight portion is asymmetrically formed with respect to the imaginary straight line.

2. The scroll compressor as described in claim 1, characterized in that, When viewed from the axial direction of the drive shaft, the first counterweight is formed such that the mass of the portion located on the opposite side of the imaginary straight line from the eccentric pin is greater than the mass of the portion located on the same side of the imaginary straight line from the eccentric pin.

3. The scroll compressor as described in claim 1 or 2, characterized in that, When viewed from the axial direction of the drive shaft, the second counterweight includes a pair of protrusions that project toward the shaft balancer and sandwich the imaginary straight line and are separated from each other, with a portion of the shaft balancer disposed between the pair of protrusions.

4. The scroll compressor as described in claim 3, characterized in that, The mass of the bushing balancer is greater than the mass of the shaft balancer, and the distance from the center line of the drive shaft to the front end of the first counterweight is greater than the distance from the center line of the drive shaft to the front end of the second counterweight.

5. The scroll compressor as described in any one of claims 1 to 4, characterized in that, The scroll compressor further includes: an electric motor having a rotor fixed to the drive shaft and a stator core unit disposed radially outward of the rotor, and driving the drive shaft to rotate; a first rotor balancer fixed to the end face of the rotor on the shaft balancer side and disposed on the opposite side of the eccentric pin relative to the centerline of the drive shaft; and a second rotor balancer fixed to the end face of the rotor on the opposite side of the shaft balancer side and disposed on the same side of the eccentric pin relative to the centerline of the drive shaft.

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