CO-ROTATING SCROLL COMPRESSOR

Description

TECHNICAL FIELD

The present invention relates to a co-rotating scroll compressor.

BACKGROUND ART

A conventional co-rotating scroll compressor is disclosed in Patent Literature 1. This co-rotating scroll compressor includes a driving mechanism, a driving scroll, a driven mechanism, a driven scroll, and a housing.

The housing has a suction chamber into which a fluid is sucked from an outside of the housing and a discharge chamber from which the fluid is discharged to the outside of the housing.

The driving scroll is driven rotatably around a driving axis by the driving mechanism. The driven scroll is eccentric to the driving scroll and follows the driving scroll rotatably around a driven axis by the driving scroll and the driven mechanism.

The driving scroll has a driving scroll end plate and a driving scroll spiral body. The driving scroll end plate extends so as to intersect with the driving axis. The driving scroll spiral body protrudes from the driving scroll end plate toward the driven scroll and has a spiral shape.

The driven scroll has a driven scroll end plate and a driven scroll spiral body. The driven scroll end plate extends so as to intersect with the driven axis. The driven scroll spiral body protrudes from the driven scroll end plate toward the driving scroll and has a spiral shape.

The driving scroll and the driven scroll form a compression chamber with the driving scroll spiral body and the driven scroll spiral body facing with each other, the compression chamber changing its volume by the rotational driving of the driving scroll and the rotational following of the driven scroll. The fluid sucked from the suction chamber is compressed according to its volume change and discharged to the discharge chamber.

In this co-rotating scroll compressor, a pair of bearings is provided with the driving scroll and the driven scroll interposed therebetween. The driving scroll is rotatably supported by the driving side bearing and the driven scroll is rotatably supported by the driven side bearing. In other words, this co-rotating scroll compressor is a cantilever type compressor in which the driving scroll and the driven scroll are each supported at its one side relative to the housing.

In addition, another conventional co-rotating scroll compressor of doubly supported type is disclosed in Patent Literature 2. In this co-rotating scroll compressor, a driving scroll is supported at its both sides relative to a housing and a driven scroll is supported at its one side relative to the housing. This driving scroll has a cover body that faces a driving scroll end plate in a direction in which a driving axis extends and is coupled to the driving scroll end plate with a driven scroll interposed between the driving scroll end plate and the cover body. Here, a first shaft supported portion formed in the driving scroll end plate is supported by a first shaft supporting portion of the housing via a first bearing, and a second shaft supported portion formed in the cover body is supported by a second shaft supporting portion of the housing via a second bearing. In addition, in the driven scroll, a third shaft supported portion formed in the driven scroll end plate is supported by a third shaft supporting portion of the housing via a third bearing.

CITATION LIST

Patent Literature

• Patent Literature 1: Japanese Patent Application Publication No. 2002-310073
• Patent Literature 2: Japanese Patent Application Publication No. H07-229480

SUMMARY OF INVENTION

Technical Problem

However, even in any cantilever type or doubly supported type co-rotating scroll compressor, both the driving scroll and the driven scroll are just supported by the housing via the bearings, so that an entire scroll compression part that is formed of the driving scroll and the driven scroll may move in a thrust direction relative to the housing.

In such a configuration, for example, in a case where the scroll compression part is accommodated in a suction chamber, when a discharge pressure is applied to this scroll compression part from one side in the thrust direction, the scroll compression part is pushed toward the other side in the thrust direction. Accordingly, in this case, the scroll compression part needs to have, on the other side thereof, a structure to bear a thrust load transferred from the scroll compression part. As for the structure to bear the thrust load, for example, when a ball bearing is used as a radial bearing that can bear the thrust load, there is a concern about a problem of noise and vibrations, or when both the radial bearing and a thrust bearing are used, there is a concern about an increase in required power.

The present invention is made in view of the above-mentioned conventional circumstances, and is directed to providing a co-rotating scroll compressor in which noise, vibrations, and an increase in required power are suppressed by reducing a thrust load that is transferred from a scroll compression part to a housing.

Solution to Problem

A co-rotating scroll compressor of the present invention is a co-rotating scroll compressor including:

• • a housing having a suction chamber into which a fluid is sucked from an outside of the co-rotating scroll compressor and a discharge chamber from which the fluid is discharged to the outside of the co-rotating scroll compressor;
  • a first scroll provided in the housing; and
  • a second scroll provided in the housing and facing the first scroll, the second scroll forming, together with the first scroll, a compression chamber in which the fluid is compressed, between the second scroll and the first scroll,
  • the first scroll having a first end plate and a first spiral body that is formed integrally with the first end plate and has a spiral shape protruding toward the second scroll, and
  • the second scroll having a second end plate and a second spiral body that is formed integrally with the second end plate and has a spiral shape protruding toward the first scroll, characterized in that
  • a scroll compression part is formed of the first scroll and the second scroll,
  • a pressure adjustment chamber is formed on one side in a thrust direction of the scroll compression part, and when the fluid at a suction pressure in the suction chamber, a discharge pressure in the discharge chamber, or an intermediate pressure between the suction pressure and the discharge pressure is introduced into the pressure adjustment chamber, the pressure adjustment chamber reduces a thrust load that is applied to the scroll compression part in the thrust direction.

In the co-rotating scroll compressor of the present invention, for example, in a case where the scroll compression part is accommodated in the suction chamber, when a discharge pressure is applied to the scroll compression part from the other side in the thrust direction, a thrust load to be transferred to the housing toward the one side in the thrust direction is applied to the scroll compression part. In addition, for example, when a suction pressure is applied to the scroll compression part that is accommodated in the discharge chamber from the other side in the thrust direction, a thrust load to be transferred to the housing toward the other side of the thrust direction is applied to the scroll compression part.

In this regard, in the co-rotating scroll compressor of the present invention, the pressure adjustment chamber into which the fluid at a predetermined pressure is introduced is located on the one side in the thrust direction of the scroll compression part. The pressure of the fluid that is introduced into this pressure adjustment chamber is applied so as to reduce the thrust load that is applied to the scroll compression part by the pressure of the fluid that is applied to the scroll compression part in the thrust direction. This reduces the thrust load that is transferred from the scroll compression part to the housing.

Thus, according to this co-rotating scroll compressor, the thrust load that is transferred from the scroll compression part to the housing is reduced, so that noise, vibrations, and an increase in required power are suppressed.

In a case where the suction chamber is a scroll accommodating chamber in which the scroll compression part is accommodated, the discharge pressure in the discharge chamber is applied to the scroll compression part from the other side in the thrust direction, and the fluid at the discharge pressure or the intermediate pressure is preferably introduced into the pressure adjustment chamber.

In the case where the scroll compression part is accommodated in the suction chamber and the discharge pressure in the discharge chamber is applied to the scroll compression part from the other side of the thrust direction, even when the fluid at the discharge pressure or the intermediate pressure is introduced into the pressure adjustment chamber, the discharge pressure or the intermediate pressure of the fluid introduced into the compression adjustment pressure opposes the discharge pressure that is applied to the scroll compression part from the other side in the thrust direction. Thus, the thrust load that is applied to the scroll compression part by the discharge pressure from the other side in the thrust direction is reduced. As a result, the thrust load that is transferred from the scroll compression part to the housing toward the one side in the thrust direction is reduced.

The first scroll may have a first shaft supported portion that extends from the first end plate away from the compression chamber, a cover body that faces the first end plate in the thrust direction and is coupled to the first end plate with the second scroll interposed between the first end plate and the cover body, and a second shaft supported portion that extends from the cover body away from the compression chamber.

The second scroll may have a third shaft supported portion that is formed in the second end plate opposite to the compression chamber.

The housing may have a first separation wall that faces the first end plate in the thrust direction and by which the scroll accommodating chamber is defined, a first shaft supporting portion that is formed in the first separation wall, a second separation wall that faces the cover body in the thrust direction and by which the scroll accommodating chamber is defined, and a second shaft supporting portion that is formed in the second separation wall, and the housing may further have a third shaft supporting portion that is eccentric to the second shaft supporting portion. These first to third shaft supported portions may be supported by the first to third shaft supporting portions via bearings, respectively.

The pressure adjustment chamber is preferably formed between the second end plate and the third shaft supporting portion. The pressure adjustment chamber is preferably formed between the second end plate and the second shaft supporting portion. The pressure adjustment chamber is preferably formed between the cover body and the second separation wall. The pressure adjustment chamber is preferably formed between the second end plate and the third shaft supporting portion and also between the second end plate and the second shaft supporting portion. The pressure adjustment chamber is preferably formed between the second end plate and the third shaft supporting portion and also between the cover body and the second separation wall.

In this case, the entire scroll compression part that is formed of the first scroll that is supported relative to the housing in a doubly supported manner and the second scroll that is supported relative to the housing in a cantilever manner is supported by the first shaft supporting portion, the second shaft supporting portion, and the third shaft supporting portion of the housing.

Then, the pressure adjustment chamber is formed between the second end plate and the third shaft supporting portion, between the second end plate and the second shaft supporting portion, or between the cover body and the second separation wall. Alternatively, the pressure adjustment chamber is formed between the second end plate and the third shaft supporting portion and between the second end plate and the second shaft supporting portion, or the pressure adjustment chamber is formed between the second end plate and the third shaft supporting portion and between the cover body and the second separation wall.

With such a configuration, in a case where the discharge pressure in the discharge chamber is applied to the scroll compression part from the other side in the thrust direction, even when the fluid at the discharge pressure or the intermediate pressure is introduced into the pressure adjustment chamber, the discharge pressure or the intermediate pressure of the fluid introduced into the pressure adjustment chamber opposes the discharge pressure that is applied to the scroll compression part from the other side in the thrust direction. Thus, the thrust load that is applied to the scroll compression part by the discharge pressure from the other side in the thrust direction is reduced. As a result, the thrust load that is transferred from the scroll compression part to the housing toward the one side in the thrust direction is reduced.

In addition, in this case, the second scroll is pushed against the first scroll toward the other side in the thrust direction by the discharge pressure or the intermediate pressure of the fluid introduced into the pressure adjustment chamber. This improves a sealing performance between a distal end of the first spiral body and the second end plate and between a distal end of the second spiral body and the first end plate.

In the case where the suction chamber is a scroll accommodating chamber in which the scroll compression part is accommodated, preferably, on the one side in the thrust direction of the scroll compression part, the discharge chamber to which the fluid is discharged from the compression chamber is formed and a separation wall that closes an opening of the discharge chamber on the one side is provided. The discharge chamber and the outside of the housing preferably communicate with each other through a discharge passage that extends in a direction intersecting with the thrust direction. The pressure adjustment chamber is preferably formed between an end surface of the separation wall opposite to the discharge chamber and a housing facing surface that faces the end surface, and the fluid at the suction pressure is preferably introduced into this pressure adjustment chamber.

The discharge chamber to which the fluid is discharged from the compression chamber is formed on the one side in the thrust direction of the scroll compression part, and when the discharge chamber is open in the thrust direction, a thrust load toward the other side in the thrust direction is applied to the scroll compression part by the discharge pressure in the discharge chamber. In this regard, the pressure adjustment chamber is located via the separation wall that closes the opening of the discharge chamber on the one side, the fluid at the suction pressure is introduced into this pressure adjustment chamber, and the discharge chamber and the outside of the housing communicate with each other through the discharge passage that extends in the direction intersecting with the thrust direction. Thus, the thrust load is not applied to the scroll compression part because of the discharge pressure in the discharge chamber. Thus, the thrust load that is transferred from a scroll compression to the housing is reduced.

A thrust bearing is preferably provided between the housing and the scroll compression part.

In this case, the thrust bearing may bear the thrust load that is transferred from the scroll compression part to the housing. As compared with a case where the pressure adjustment chamber is not formed, the thrust load to which this thrust bearing is subjected is reduced, so that the increase in required power by providing this thrust bearing is suppressed.

At least one of the bearings is preferably a sliding bearing.

In this case, it is more advantageous in suppressing noise and vibrations as compared with a case where the scroll compression part is supported relative to the housing by a ball bearing.

Advantageous Effects of Invention

According to the co-rotating scroll compressor of the present invention, the thrust load that is transferred from the scroll compression part to the housing is reduced, which suppresses noise, vibrations, and the increase in required power.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view of a co-rotating scroll compressor of a first embodiment.

FIG. 2 is an enlarged partial cross-sectional view illustrating a main part of the co-rotating scroll compressor according to the co-rotating scroll compressor of the first embodiment.

FIG. 3 is an enlarged partial cross-sectional view illustrating a main part of a co-rotating scroll compressor according to the co-rotating scroll compressor of a second embodiment.

FIG. 4 is an enlarged partial cross-sectional view illustrating a main part of a co-rotating scroll compressor according to the co-rotating scroll compressor of a third embodiment.

FIG. 5 is an enlarged partial cross-sectional view illustrating a main part of a co-rotating scroll compressor according to the co-rotating scroll compressor of a fourth embodiment.

FIG. 6 is an enlarged partial cross-sectional view illustrating a main part of a co-rotating scroll compressor according to the co-rotating scroll compressor of a fifth embodiment.

FIG. 7 is a cross-sectional view of a co-rotating scroll compressor of a sixth embodiment.

FIG. 8 is a cross-sectional view of a co-rotating scroll compressor of a reference example.

DESCRIPTION OF EMBODIMENTS

The following will describe a first embodiment to a sixth embodiment according to the present invention with reference to the drawings.

First Embodiment

As illustrated in FIG. 1, a co-rotating scroll compressor (hereinafter, simply referred to as the compressor) of the first embodiment includes a housing 60, a scroll compression part 80, an electric motor 10, a driving scroll 30, a driven scroll 40, and a driven mechanism 20. This compressor is mounted on a vehicle, which is not illustrated, and is a part of an air conditioner for the vehicle.

In the present embodiment, a front-rear direction of the compressor is defined by a solid arrow illustrated in FIG. 1. Note that the front-rear direction is an example for convenience of explanation, and a posture of the compressor may be changed as appropriate depending on the vehicle on which the compressor is mounted.

In the present embodiment, the driving scroll 30, a driving scroll end plate 31 which will be described later, and a driving scroll spiral body 33 which will be described later, correspond to the “first scroll”, the “first end plate”, and the “first spiral body” in the present invention, respectively. In addition, the driven scroll 40, a driven scroll end plate 41 which will be described later, and a driven scroll spiral body 43 which will be described later, correspond to the “second scroll”, the “second end plate”, the “second spiral body” in the present invention, respectively.

The housing 60 is formed of a housing body 61, a cover 65, and a bearing housing 67. The housing body 61 is a bottomed tubular member having a first outer peripheral wall 62 and a first bottom wall 63. The first bottom wall 63 is an example of the “second separation wall” in the present invention. The first outer peripheral wall 62 is formed in a cylindrical shape extending around a driving axis R1. The driving axis R1 is parallel to the front-rear direction. In addition, the first outer peripheral wall 62 has an inner peripheral surface 62B. The first bottom wall 63 is located at a rear end of the housing body 61. The first bottom wall 63 is formed in a substantially circular flat plate shape extending perpendicularly to the driving axis R1.

An outer peripheral edge of the first bottom wall 63 is connected to a rear end of the first outer peripheral wall 62. A second shaft supporting portion 64 has a columnar shape protruding forward from a center of an inner surface of the first bottom wall 63.

A third shaft supporting portion 90 has a columnar shape that is disposed adjacent to a distal end surface 641 of the second shaft supporting portion 64 and eccentric to the second shaft supporting portion 64. An eccentric shaft 91 is fixed to the second shaft supporting portion 64. The eccentric shaft 91 extends out over the distal end surface 641 of the second shaft supporting portion 64 forward in parallel to the driving axis R1. The eccentric shaft 91 is eccentric to the driving axis R1. The third shaft supporting portion 90 is attached to the eccentric shaft 91 so as to be rotatable. A third sliding bearing 73 is interposed between this third shaft supporting portion 90 and a recess 74, which will be described later. With these configurations, the third shaft supporting portion 90 is rotatable relative to the eccentric shaft 91 and the recess 74, which will be described later.

A suction communication port 61B is formed in the first outer peripheral wall 62 of the housing body 61. The suction communication port 61B is located near the rear end of the first outer peripheral wall 62 and extends through the first outer peripheral wall 62 in a direction intersecting with the driving axis R1. A suction chamber 61A, which will be described later, and an outside of the compressor communicate with each other through the suction communication port 61B. A tube is connected to the suction communication port 61B. Accordingly, refrigerant gas at low temperature and low pressure after flowing through an evaporator is sucked into the suction chamber 61A through the tube. The refrigerant gas is an example of the “fluid” in the present invention.

An inverter case with a connector portion is located behind the housing body 61 and coupled to the housing body 61. An inverter circuit having a circuit board and switching elements or the like is accommodated in the inverter case. The inverter circuit is electrically connected to a battery of the vehicle through a connector and to a stator 17, which will be described later, through a hermetic passage formed in the first bottom wall 63. With these connections, the inverter circuit converts DC current supplied from the battery to AC current and supplies its power to the stator 17. Note that illustrations of the connector portion, the inverter case, the inverter circuit, and the battery are omitted.

The bearing housing 67 is disposed in front of the housing body 61. The bearing housing 67 is an example of the “first separation wall” in the present invention. The bearing housing 67 has a substantially circular flat plate shape extending perpendicularly to the driving axis R1. The bearing housing 67 is fastened together with the cover 65 to the first outer peripheral wall 62 by bolts, which are not illustrated, with an outer peripheral edge of the bearing housing 67 in contact with a front end of the first outer peripheral wall 62 of the housing body 61. With this configuration, the bearing housing 67 closes the housing body 61 at a front thereof. Thus, the suction chamber 61A is formed in the housing body 61.

A first shaft supporting portion 66 is formed at a center of the bearing housing 67 and has a cylindrical shape extending around the driving axis R1. A first sliding bearing 71 as the first bearing is fitted into the first shaft supporting portion 66. The first sliding bearing 71 is an example of the “bearing” in the present invention.

The cover 65 is disposed in front of the bearing housing 67. The cover 65 is a bottomed tubular member having a second outer peripheral wall 68 and a second bottom wall 69. The second outer peripheral wall 68 is formed in a cylindrical shape extending around the driving axis R1. The second bottom wall 69 is located at a front end of the cover 65. The second bottom wall 69 has a substantially circular flat plate shape extending perpendicularly to the driving axis R1. An outer peripheral edge of the second bottom wall 69 is connected to a front end of the second outer peripheral wall 68.

The cover 65 is fastened together with the bearing housing 67 to the first outer peripheral wall 62 by the bolts, which are not illustrated, with a rear end of the second outer peripheral wall 68 in contact with a front surface of the bearing housing 67. As a result, a second discharge portion 65A is formed between the cover 65 and the bearing housing 67. The second discharge portion 65A is located in front of and adjacent to the suction chamber 61A. The second discharge portion 65A is separated from the suction chamber 61A by the bearing housing 67.

A discharge communication port 65B is formed in the cover 65. The discharge communication port 65B is located near an outer peripheral edge of the cover 65 and extends through the cover 65 in parallel to the driving axis R1. The second discharge portion 65A and the outside of the compressor communicate with each other through the discharge communication port 65B. A tube is connected to the discharge communication port 65B and the refrigerant gas discharged to the second discharge portion 65A flows toward a condenser through the tube. Note that illustrations of the tubes, the evaporator, and the condenser are omitted.

The electric motor 10 is accommodated in the suction chamber 61A. That is, the suction chamber 61A also serves as a motor chamber in which the electric motor 10 is accommodated. The electric motor 10 includes the stator 17 and a rotor 11.

The stator 17 is formed in a cylindrical shape extending around the driving axis R1 and has a winding 18. The stator 17 is fitted into the inner peripheral surface 62B of the first outer peripheral wall 62 of the housing body 61, so that the stator 17 is fixed to the housing body 61, and by extension, to the housing 60.

The rotor 11 is formed in a cylindrical shape extending around the driving axis R1 and disposed inside the stator 17. Although a detailed illustration is omitted, the rotor 11 is formed of a plurality of permanent magnets corresponding to the stator 17 and laminated steel plates for fixing the permanent magnets.

The scroll compression part 80 is accommodated in the suction chamber 61A. That is, the suction chamber 61A also serves as a scroll accommodating chamber in which the scroll compression part 80 is accommodated. The suction chamber 61A is an example of the “scroll accommodating chamber” in the present invention. The scroll compression part 80 is formed of the driving scroll 30 and the driven scroll 40.

The driving scroll 30 has the driving scroll end plate 31, a driving scroll peripheral wall 32, the driving scroll spiral body 33, a bearing cover body 34, and a cover body 35.

The driving scroll end plate 31 is formed in a substantially circular plate shape extending perpendicularly to the driving axis R1. The driving scroll end plate 31 has a front surface 311 and a rear surface 312 located opposite the front surface 311.

A discharge valve chamber 36 is formed in the driving scroll end plate 31 and opened in the front surface 311 of the driving scroll end plate 31. The discharge valve chamber 36 is formed of a recess that is partially recessed in the front surface 311 toward a compression chamber 55, which will be described later. The discharge valve chamber 36 has an inner surface shape substantially corresponding to an outer shape of a discharge valve mechanism 56, which will be described later, so that the discharge valve chamber 36 may accommodate the discharge valve mechanism 56. Furthermore, a discharge port 37 is formed near a center of the driving scroll end plate 31 and extends through the driving scroll end plate 31 in the front-rear direction. The discharge port 37 is, at one end thereof, opened to the compression chamber 55, which will be described later. The discharge port 37 is, at the other end thereof, opened in a bottom surface of the discharge valve chamber 36. That is, the compression chamber 55 and the discharge valve chamber 36 communicate with each other through the discharge port 37. The discharge port 37 is located near the driving axis R1.

The discharge valve mechanism 56 is provided in the discharge valve chamber 36. The discharge valve mechanism 56 has a discharge reed valve 57, a retainer 58, and bolts 59. The discharge reed valve 57 and the retainer 58 are fixed to the bottom surface of the discharge valve chamber 36 by the bolts 59. The discharge reed valve 57 is capable of opening and closing the discharge port 37. Furthermore, an opening degree of the discharge reed valve 57 is adjustable by the retainer 58. In the discharge reed valve 57, a valve distal portion that opens and closes the discharge port 37 is located closer to the driving axis R1 as compared to a valve fixed proximal end portion that is fixed by the bolts 59.

The driving scroll spiral body 33 is formed integrally with the driving scroll end plate 31 and located inside the driving scroll peripheral wall 32. The driving scroll spiral body 33 extends rearward from the rear surface 312 of the driving scroll end plate 31 in parallel to the driving axis R1. The driving scroll spiral body 33 has a spiral shape around the driving axis R1. More specifically, the driving scroll spiral body 33 is formed in a right-handed spiral shape around the driving axis R1, starting from a center of the spiral, as viewed from a front side of the driving scroll spiral body 33.

The driving scroll peripheral wall 32 has the rotor 11 disposed on an outer peripheral edge of the rear surface 312 of the driving scroll end plate 31 and a cylindrical portion 51 of the cover body 35 behind the rotor 11. The cylindrical portion 51 will be described later. The driving scroll peripheral wall 32 extends in parallel to the driving axis R1 from the outer peripheral edge of the driving scroll end plate 31 rearward, that is, toward the driven scroll 40. The driving scroll peripheral wall 32 has a substantially cylindrical shape extending around the driving axis R1.

The cover body 35 has a bottomed tubular member having the cylindrical portion 51 and a bottom wall portion 52. The cylindrical portion 51 is formed in a cylindrical shape extending around the driving axis R1. The bottom wall portion 52 is located at a rear end of the cover body 35. The bottom wall portion 52 has a substantially circular flat plate shape extending perpendicularly to the driving axis R1.

An outer peripheral edge of the bottom wall portion 52 is connected to a rear end of the cylindrical portion 51. A second boss 53 is formed at a center of the bottom wall portion 52 so as to protrude rearward. The second boss 53 is an example of the “second shaft supported portion” in the present invention. A second sliding bearing 72 as the second bearing is fitted into the second boss 53. The second sliding bearing 72 is an example of the “bearing” of the present invention. The second boss 53 has a cylindrical shape extending in a direction in which the driving axis R1 extends around the driving axis R1.

A suction port 54 is formed near the outer peripheral edge of the bottom wall portion 52. The suction port 54 is formed in a substantially elliptical shape extending in a circumferential direction of the cover body 35. The suction port 54 extends through the bottom wall portion 52 in the direction in which the driving axis R1 extends, that is, in the front-rear direction. Note that the shape of the suction port 54 and the number of the suction ports 54 may be designed as appropriate.

The bearing cover body 34 has a cover portion 38 and a first boss 39 formed integrally with the cover portion 38.

The cover portion 38 has a substantially circular plate shape extending perpendicularly to the driving axis R1. The cover portion 38 has a front surface 381 and a rear surface 382 located opposite the front surface 381. The cover portion 38 has, at a center thereof, a through hole 38A.

The first boss 39 protrudes forward from an inner peripheral edge of the cover portion 38, that is, a center of the front surface 381 of the cover portion 38. The first boss 39 is an example of the “first shaft supported portion” in the present invention. The first boss 39 has a cylindrical shape extending in the direction in which the driving axis R1 extends around the driving axis R1. An inner space having a columnar shape in the first boss 39 forms a first discharge portion 39A. An inner diameter of the first discharge portion 39A, which is the inner space having the columnar shape in the first boss 39, and an outer diameter of the first boss 39 are shorter than a length of the longest portion of the discharge valve mechanism 56. Note that in this compressor, a discharge chamber is formed of the discharge valve chamber 36, the first discharge portion 39A, and the second discharge portion 65A.

A gasket having a circular plate shape, which is not illustrated, is disposed between the rear surface 382 of the cover portion 38 and the front surface 311 of the driving scroll end plate 31. A communicating port with a diameter equal to the inner diameter of the first boss 39 is formed at a center of the gasket and extends through the gasket. The gasket is held between the front surface 311 of the driving scroll end plate 31 and the rear surface 382 of the cover portion 38 and provides a seal therebetween.

The cover portion 38 of the bearing cover body 34, the gasket, which is not illustrated, the driving scroll end plate 31 of the driving scroll 30, the rotor 11, and the cylindrical portion 51 of the cover body 35 are fastened to each other by a plurality of bolts 50 extending in parallel to the driving axis R1. These members are coupled to each other by the bolts 50 after the driven mechanism 20 and the driven scroll 40 are set to the cover body 35 and the discharge valve mechanism 56 is set in the driving scroll end plate 31.

The driven scroll 40 has the driven scroll end plate 41 and the driven scroll spiral body 43.

The driven scroll end plate 41 is formed in a substantially circular plate shape extending perpendicularly to a driven axis R2. The driven axis R2 is eccentric to the driving axis R1 and extends in parallel to the driving axis R1. That is, the driven axis R2 is also parallel to the front-rear direction. The direction in which the driving axis R1 extends and a direction in which the driven axis R2 extends, that is, the front-rear direction, coincide with a thrust direction. Furthermore, in this embodiment, a front side corresponds to “the other side in the thrust direction” in the present invention, and a rear side corresponds to the “one side in the thrust direction” in the present invention. The driven scroll end plate 41 has a front surface 411 and a rear surface 412 located opposite the front surface 411.

As illustrated in FIG. 2, the recess 74 is formed at a center of the driven scroll end plate 41 and has a columnar shape such that the recess 74 is partially recessed in the rear surface 412 of the driven scroll end plate 41 toward the compression chamber 55. The recess 74 is an example of the “third shaft supported portion” in the present invention. The recess 74 is formed in a columnar shape extending in the direction in which the driven axis R2 extends around the driven axis R2. The recess 74 has an inner surface shape corresponding to an outer shape of the third shaft supporting portion 90.

A first pressure adjustment chamber 76 is formed between a bottom surface 75 of the recess 74 and a distal end surface 92 of the third shaft supporting portion 90 and defined by them. The first pressure adjustment chamber 76 is an example of the “pressure adjustment chamber” in the present invention.

The third sliding bearing 73 as the third bearing is fitted into an inner peripheral surface of the recess 74. The third sliding bearing 73 is an example of the “bearing” in the present invention.

A first sealing ring 93 is provided behind the first pressure adjustment chamber 76 and between the inner peripheral surface of the recess 74 and an outer peripheral surface of the third shaft supporting portion 90. The first sealing ring 93 is inserted in an annular groove that is recessed in the outer peripheral surface of the third shaft supporting portion 90 and provides a seal between the inner peripheral surface of the recess 74 and the outer peripheral surface of the third shaft supporting portion 90. The first sealing ring 93 is located in front of the third sliding bearing 73.

A first communication passage 77 is formed near the center of the driven scroll end plate 41 and extends through the driven scroll end plate 41 in the front-rear direction. The first communication passage 77 is, at one end thereof, opened to the compression chamber 55 and the first communication passage 77 is, at the other end thereof, opened in the bottom surface 75 of the recess 74. That is, the compression chamber 55 and the first pressure adjustment chamber 76 communicate with each other through the first communication passage 77. The first communication passage 77 is located near the driven axis R2.

The driven scroll spiral body 43 is formed integrally with the driven scroll end plate 41 and extends in parallel to the driven axis R2 from the front surface 411 of the driven scroll end plate 41 forward, that is, toward the driving scroll end plate 31 of the driving scroll 30. The driven scroll spiral body 43 has a spiral shape around the driven axis R2. More specifically, the driven scroll spiral body 43 is formed in a right-handed spiral shape around the driven axis R2, starting from a center of the spiral, as viewed from a front of the driven scroll spiral body 43.

The driven mechanism 20 is formed of four anti-rotation pins 21 and four rings 22. Note that the number of the anti-rotation pins 21 and the number of the rings 22 may be designed as appropriate as long as each of them is three or more. In addition, two of the anti-rotation pins 21 and two of the rings 22 are illustrated in FIG. 1.

The anti-rotation pins 21 are inserted into and fixed to the rear surface 412 of the driven scroll end plate 41. Thus, the anti-rotation pins 21 are fixed to the driven scroll end plate 41 so that the anti-rotation pins 21 extends out rearward over the driven scroll end plate 41.

Each ring 22 is provided in a front surface 521 of the bottom wall portion 52 of the cover body 35 of the driving scroll 30 so as to face the corresponding anti-rotation pin 21. The rings 22 are fitted into bottomed circular holes that are recessed in a front surface 521 of the bottom wall portion 52.

In this compressor, the scroll compression part 80 that is formed of the driving scroll 30 and the driven scroll 40 is disposed in the suction chamber 61A.

In the driving scroll 30, the rotor 11 is integrated with the driving scroll peripheral wall 32. Furthermore, in the driving scroll 30, the first sliding bearing 71 is interposed between the first shaft supporting portion 66 of the bearing housing 67 and the first boss 39 of the bearing cover body 34, and the second sliding bearing 72 is interposed between the second shaft supporting portion 64 of the first bottom wall 63 and the second boss 53 of the cover body 35. With these configurations, the driving scroll 30 is supported by the housing 60 so as to be rotatable around the driving axis R1. Here, in this compressor, the driving scroll 30 is supported in a so-called doubly supported manner by the housing 60.

On the other hand, the driven scroll 40 is located behind the driving scroll end plate 31 in the driving scroll 30 with the driven scroll spiral body 43 facing the driving scroll end plate 31. With this configuration, the rear surface 312 of the driving scroll end plate 31 and the front surface 411 of the driven scroll end plate 41 face each other in the direction in which the driving axis R1 extends and in the direction in which the driven axis R2 extends. Then, in the driving scroll 30 and the driven scroll 40, the driving scroll spiral body 33 is engaged with the driven scroll spiral body 43 inside the driving scroll peripheral wall 32, and the anti-rotation pins 21 are inserted into the corresponding rings 22. Thus, the driven scroll 40 is assembled to the driving scroll 30 therein with the driving scroll end plate 31 and the driven scroll end plate 41 facing each other in the front-rear direction. The driving scroll spiral body 33 and the driven scroll spiral body 43 form the compression chamber 55 therebetween.

In the driven scroll 40, the third sliding bearing 73 is interposed between the third shaft supporting portion 90, which is eccentric to the second shaft supporting portion 64 of the first bottom wall 63, and the recess 74 of the driven scroll end plate 41. With this configuration, the driven scroll 40 is supported by the housing 60 so as to be rotatable around the driven axis R2. Here, in this compressor, the driven scroll 40 is supported in a so-called cantilever manner by the housing 60.

In this compressor having the configuration described above, while the inverter circuit, which is not illustrated, supplies power to the stator 17, the inverter circuit controls operation of the electric motor 10, which operates the electric motor 10. This rotates the rotor 11, and the driving scroll 30 is driven rotatably around the driving axis R1 in the suction chamber 61A. That is, the driving scroll 30 including the driving scroll peripheral wall 32 integrated with the rotor 11 is rotatably driven. Here, in the driven mechanism 20, each of the anti-rotation pins 21 slides on an inner peripheral surface of the corresponding ring 22 to rotate the ring 22 relative to the anti-rotation pin 21 around a center of the anti-rotation pin 21. Thus, the driven mechanism 20 transfers torque of the driving scroll 30 to the driven scroll 40.

As a result, the driven scroll 40 follows the driving scroll 30 rotatably around the driven axis R2 by the driving scroll 30 and the driven mechanism 20. Here, the driven mechanism 20 prevents the driven scroll 40 from rotating. This causes the driven scroll 40 to orbit around the driving axis R1 relative to the driving scroll 30 by the rotational driving of the driving scroll 30 and the rotational following of the driven scroll 40, which changes a volume of the compression chamber 55.

Thus, the refrigerant gas in the suction chamber 61A is sucked into the compression chamber 55 through the suction port 54, and then, compressed in the compression chamber 55. The refrigerant gas that has reached a discharge pressure by the compression in the compression chamber 55 is discharged to the discharge valve chamber 36 through the discharge port 37. After that, the refrigerant gas is discharged to the second discharge portion 65A through the first discharge portion 39A, and then, discharged to the condenser through the discharge communication port 65B. Thus, air conditioning by the air conditioner for the vehicle is performed.

Here, in this compressor, the scroll compression part 80 is accommodated in the suction chamber 61A, and during the operation of the compressor, the discharge pressure in the discharge chamber is applied to the scroll compression part 80 from the other side in the thrust direction, that is, from the front side. Accordingly, a thrust load to be transferred to the housing 60 toward the one side in the thrust direction, that is, toward the rear side is applied to the scroll compression part 80.

In this regard, in the compressor of the first embodiment, the first pressure adjustment chamber 76 is located behind the compression chamber 55 in the scroll compression part 80. The refrigerant gas at the discharge pressure in the compression chamber 55 is introduced into this first pressure adjustment chamber 76 through the first communication passage 77. The discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 opposes the discharge pressure in the discharge chamber that is applied to the scroll compression part 80 from the discharge chamber on the front side. That is, the discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 is applied so as to reduce the thrust load of the scroll compression part 80, which is oriented rearward and transferred to the third shaft supporting portion 90 of the housing 60. Thus, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced.

According to the co-rotating scroll compressor of the first embodiment, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced, so that noise, vibrations, and an increase in required power are suppressed.

In this compressor, the driven scroll 40 is pushed against the driving scroll 30 toward the other side in the thrust direction, that is, forward, by the discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76. As a result, a sealing performance between a distal end of the driving scroll spiral body 33 and the front surface 411 of the driven scroll end plate 41 and between a distal end of the driven scroll spiral body 43 and the rear surface 312 of the driving scroll end plate 31 is improved. This contributes to improved compression efficiency.

In this compressor, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced behind the compression chamber 55 in the scroll compression part 80, so that there is no need to bear a large thrust load at a rear side of the scroll compression part 80. Thus, on the rear side of the scroll compression part 80, the second sliding bearing 72 as the second bearing supporting the second boss 53 of the driving scroll 30 and the third sliding bearing 73 as the third bearing supporting the recess 74 of the driven scroll 40 are used. With this configuration, it is more advantageous in suppressing noise and vibrations as compared with a case where a ball bearing is used.

Furthermore, in this compressor, in the driving scroll 30, the bearing cover body 34 having the cover portion 38 that covers a part of the discharge valve chamber 36 and a part of the discharge valve mechanism 56 is coupled to the front surface 311 of the driving scroll end plate 31 in which the discharge valve chamber 36 accommodating the discharge valve mechanism 56 is recessed. In addition, the first discharge portion 39A, which is the inner space of the first boss 39 of the bearing cover body 34, communicates with the discharge valve chamber 36.

With these configurations, in this compressor, the discharge valve mechanism 56 is not accommodated in the first discharge portion 39A, which is the inner space of the first boss 39, so that the inner diameter of the first discharge portion 39A does not need to be larger than a size of the discharge valve mechanism 56. Accordingly, in this compressor, the inner diameter of the first discharge portion 39A and the outer diameter of the first boss 39 are shorter than the length of the longest portion of the discharge valve mechanism 56. This decreases a size of the first sliding bearing 71 that is attached to an outer peripheral surface of the first boss 39.

Second Embodiment

As illustrated in FIG. 3, as for a compressor of the second embodiment, a second pressure adjustment chamber 79 is formed in the compressor of the first embodiment in addition to the first pressure adjustment chamber 76. The second pressure adjustment chamber 79 is an example of the “pressure adjustment chamber” in the present invention.

That is, in the rear surface 412 of the driven scroll end plate 41, a first annular recess 78 is formed outside the recess 74 and has an annular shape that is recessed in the rear surface 412 toward the compression chamber 55. An inner peripheral end of the first annular recess 78 is connected to a rear end of the recess 74, so that the recess 74 is continuous with the first annular recess 78.

A second sealing ring 94 is provided outside the first annular recess 78 between the driven scroll end plate 41 and the cover body 35. The second sealing ring 94 is inserted into an annular groove that is recessed in the rear surface 412 of the driven scroll end plate 41, and provides a seal between the rear surface 412 of the driven scroll end plate 41 and the front surface 521 of the bottom wall portion 52 of the cover body 35. In addition, a fourth sealing ring 99 is provided between the second boss 53 and the first bottom wall 63. The fourth sealing ring 99 is inserted into an annular groove that is recessed in a distal end surface 531 of the second boss 53 and provides a seal between the distal end surface 531 of the second boss 53 and a front surface 631 of the first bottom wall 63. As for this compressor, the first sealing ring 93 that is located in front of the third sliding bearing 73 in the compressor of the first embodiment is not provided.

With this configuration, the second pressure adjustment chamber 79 is formed between the bottom surface of the first annular recess 78, and the distal end surface 641 of the second shaft supporting portion 64 and the front surface 521 of the bottom wall portion 52 of the cover body 35, in addition to the first pressure adjustment chamber 76 formed between the bottom surface 75 of the recess 74 and the distal end surface 92 of the third shaft supporting portion 90.

In the compressor of the second embodiment, the first pressure adjustment chamber 76 and the second pressure adjustment chamber 79 are located behind the compression chamber 55 in the scroll compression part 80. The refrigerant gas at the discharge pressure in the compression chamber 55 is introduced into the first pressure adjustment chamber 76 through the first communication passage 77. In addition, the refrigerant gas at the discharge pressure introduced into the first pressure adjustment chamber 76 is introduced into the second pressure adjustment chamber 79 through a gap between the third shaft supporting portion 90 and the recess 74 and a gap in the third sliding bearing 73.

Thus, the discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 and the second pressure adjustment chamber 79 opposes the discharge pressure that is applied to the scroll compression part 80 from the discharge chamber on the front side. That is, the discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 and the second pressure adjustment chamber 79 is applied so as to reduce the thrust load of the scroll compression part 80, which is oriented rearward and transferred to the third shaft supporting portion 90 and the second shaft supporting portion 64 of the housing 60. As a result, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced.

The other components and operation of this compressor are the same as those of the compressor in the first embodiment. The identical components have the same reference numerals and may not be reiterated.

Third Embodiment

As illustrated in FIG. 4, as for a compressor of the third embodiment, the second pressure adjustment chamber 79 is formed in the compressor of the first embodiment instead of the first pressure adjustment chamber 76.

That is, similarly to the compressor of the second embodiment, the first annular recess 78 is formed in the rear surface 412 of the driven scroll end plate 41, the second sealing ring 94 is provided outside the first annular recess 78, and the fourth sealing ring 99 is provided between the second boss 53 and the first bottom wall 63. In this compressor, similarly to the compressor of the first embodiment, the first sealing ring 93 is provided in front of the third sliding bearing 73.

As for this compressor, the first communication passage 77 that is opened in the bottom surface 75 of the recess 74 in the compressor of the first embodiment is not formed. Instead of the first communication passage 77, a second communication passage 95 is formed in the driven scroll end plate 41 and extends through the driven scroll end plate 41 in a direction diagonal relative to the front-rear direction. The second communication passage 95 is, at a rear end thereof, opened in the bottom surface of the first annular recess 78, and the second communication passage 95 is, at a front end thereof, opened to the compression chamber 55. The opening end of the second communication passage 95 to the compression chamber 55 is located near the driving axis R1.

With this configuration, the second pressure adjustment chamber 79 is formed between the bottom surface of the first annular recess 78, and the distal end surface 641 of the second shaft supporting portion 64 and the front surface 521 of the bottom wall portion 52 of the cover body 35.

In the compressor of the third embodiment, the second pressure adjustment chamber 79 is located behind the compression chamber 55 in the scroll compression part 80. The refrigerant gas at the discharge pressure in the compression chamber 55 is introduced into the second pressure adjustment chamber 79 through the second communication passage 95.

Thus, the discharge pressure of the refrigerant gas introduced into the second pressure adjustment chamber 79 opposes the discharge pressure that is applied to the scroll compression part 80 from the discharge chamber on the front side. That is, the discharge pressure of the refrigerant gas introduced into the second pressure adjustment chamber 79 is applied so as to reduce the thrust load of the scroll compression part 80, which is oriented rearward and transferred to the second shaft supporting portion 64 of the housing 60. As a result, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced.

The other components and operation of this compressor are the same as those of the compressor in the first embodiment. The identical components have the same reference numerals and may not be reiterated.

Fourth Embodiment

As illustrated in FIG. 5, as for a compressor of the fourth embodiment, a third pressure adjustment chamber 96 is formed in the compressor of the first embodiment in addition to the first pressure adjustment chamber 76. The third pressure adjustment chamber 96 is an example of the “pressure adjustment chamber” in the present invention.

That is, a second annular recess 97 is formed in an inner peripheral portion of the distal end surface 531 of the second boss 53 and has an annular shape that is recessed in the distal end surface 531 toward the compression chamber 55. In addition, a third sealing ring 98 is provided behind the second sliding bearing 72, and the fourth sealing ring 99 is provided outside the second annular recess 97.

The third sealing ring 98 is inserted into an annular groove that is recessed in an outer peripheral surface of the second shaft supporting portion 64 behind the second sliding bearing 72, and provides a seal between the outer peripheral surface of the second shaft supporting portion 64 and an inner peripheral surface of the second boss 53. The fourth sealing ring 99 is inserted into an annular groove that is recessed in the distal end surface 531 of the second boss 53 outside the second annular recess 97, and provides a seal between the distal end surface 531 of the second boss 53 and the front surface 631 of the first bottom wall 63. In this compressor, similarly to the compressor of the first embodiment, the first sealing ring 93 is provided in front of the third sliding bearing 73.

Furthermore, a third communication passage 81 is formed in the eccentric shaft 91 and extends through the eccentric shaft 91 in the front-rear direction, and a fourth communication passage 82 is formed in the second shaft supporting portion 64. The fourth communication passage 82 is, at one end thereof, connected to a rear end of the third communication passage 81, and the fourth communication passage 82 is, at the other end thereof, opened to the outer peripheral surface of the second shaft supporting portion 64 near its rear end. The first pressure adjustment chamber 76 and the third pressure adjustment chamber 96 communicate with each other through the third communication passage 81 and the fourth communication passage 82.

With this configuration, the third pressure adjustment chamber 96 is formed also between the distal end surface 531 of the second boss 53 of the cover body 35 and the front surface 631 of the first bottom wall 63 in addition to the first pressure adjustment chamber 76 formed between the bottom surface 75 of the recess 74 and the distal end surface 92 of the third shaft supporting portion 90. The third pressure adjustment chamber 96 is an example of the “pressure adjustment chamber” in the present invention.

In the compressor of the fourth embodiment, the first pressure adjustment chamber 76 and the third pressure adjustment chamber 96 are located behind the compression chamber 55 in the scroll compression part 80. The refrigerant gas at the discharge pressure in the compression chamber 55 is introduced into the first pressure adjustment chamber 76 through the first communication passage 77. The discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 is introduced into the third pressure adjustment chamber 96 through the third communication passage 81 and the fourth communication passage 82.

Thus, the discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 and the third pressure adjustment chamber 96 opposes the discharge pressure that is applied to the scroll compression part 80 from the discharge chamber on the front side. That is, the discharge pressure of the refrigerant gas introduced into the first pressure adjustment chamber 76 and the third pressure adjustment chamber 96 is applied so as to reduce the thrust load of the scroll compression part 80, which is oriented rearward and transferred to the third shaft supporting portion 90 and the first bottom wall 63 of the housing 60. As a result, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced.

In this compressor, the driven scroll 40 is not pushed against the driving scroll 30 forward by the discharge pressure of the refrigerant gas introduced into the third pressure adjustment chamber 96. Thus, damages to the distal end of the driving scroll spiral body 33 and the distal end of the driven scroll spiral body 43 are suppressed.

The other components and operation of this compressor are the same as those of the compressor in the first embodiment. The identical components have the same reference numerals and may not be reiterated.

Fifth Embodiment

As illustrated in FIG. 6, as for a compressor of the fifth embodiment, a thrust bearing 83 is provided between the housing 60 and the scroll compression part 80 in the compressor of the fourth embodiment.

That is, the thrust bearing 83 is provided between the distal end surface 531 of the second boss 53 and the front surface 631 of the first bottom wall 63. The thrust bearing 83 is located outside the fourth sealing ring 99.

Thus, the thrust bearing 83 may bear the thrust load that is transferred from the scroll compression part 80 to the first bottom wall 63. In this compressor, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced due to operation of the first pressure adjustment chamber 76 and the third pressure adjustment chamber 96, that is, the thrust load to which the thrust bearing 83 is subjected is reduced, which suppresses an increase in required power by providing the thrust bearing 83.

The other components and operation of this compressor are the same as those of the compressor in the fourth embodiment. The identical components have the same reference numerals and may not be reiterated.

Sixth Embodiment

As illustrated in FIG. 7, as for a compressor of the sixth embodiment, a separation wall 84 having a circular plate shape is fixed at a distal end of the first boss 39 in the compressor of the first embodiment by bolts, which are not illustrated, and an opening end of the first discharge portion 39A on a front side thereof is closed by the separation wall 84. Note that in this embodiment, the second discharge portion 65A in the compressor of the first embodiment is not formed, and the discharge valve chamber 36 and the first discharge portion 39A form the discharge chamber. In addition, the front side corresponds to the “one side in the thrust direction” in the present invention.

In this compressor, a plate cover 86 is used instead of the cover 65 and the bearing housing 67 in the compressor of the first embodiment. The housing 60 is formed of the housing body 61 and the plate cover 86. The plate cover 86 is an example of the “first separation wall” in the present invention.

The plate cover 86 is a member having a substantially circular thick plate shape. The plate cover 86 is fastened to the first outer peripheral wall 62 by bolts, which are not illustrated, with an outer peripheral edge of the plate cover 86 in contact with the front end of the first outer peripheral wall 62 of the housing body 61. With this configuration, the plate cover 86 closes the housing body 61 at the front thereof. Thus, the suction chamber 61A is formed in the housing body 61. In this compressor, the suction chamber 61A is separated from the outside of the housing 60 by the plate cover 86 as the first separation wall.

A discharge communication port 86A is formed in the outer peripheral edge of the plate cover 86. The discharge communication port 86A is opened in a direction perpendicular to the driving axis R1. Furthermore, the plate cover 86 has a sixth communication passage 86B extending in the direction perpendicular to the driving axis R1. The sixth communication passage 86B is, at one end thereof, connected to the discharge communication port 86A, and the sixth communication passage 86B is, at the other end thereof, connected to a cylindrical recess 87, which will be described later.

The cylindrical recess 87 is formed at a center of a rear surface 861 of the plate cover 86 in a region corresponding to the separation wall 84 and recessed in the rear surface 861 forward. An increased diameter recess 87A with an increased inner diameter compared to an inner diameter of the cylindrical recess 87 is formed in a rear end of the cylindrical recess 87. The increased diameter recess 87A is an example of the “first shaft supporting portion” in the present invention. The first sliding bearing 71 as the first bearing is fitted into the increased diameter recess 87A. The first sliding bearing 71 is an example of the “bearing” in the present invention.

A fourth pressure adjustment chamber 88 is formed between a front surface 841 of the separation wall 84 and a bottom surface 871 of the cylindrical recess 87, which faces this front surface 841 in the front-rear direction. The fourth pressure adjustment chamber 88 is an example of the “pressure adjustment chamber” in the present invention. The front surface 841 of the separation wall 84 is an example of the “end surface of the separation wall opposite to the discharge chamber” in the present invention. The bottom surface 871 of the cylindrical recess 87 is an example of the “housing facing surface that faces the end surface” in the present invention.

A fifth communication passage 85 is formed in a peripheral wall of the first boss 39 at a distal end side thereof and extends through the peripheral wall in the direction perpendicular to the driving axis R1. This fifth communication passage 85 communicates with the sixth communication passage 86B formed in the plate cover 86. With this configuration, the first discharge portion 39A and the outside of the housing 60 communicate with each other through the fifth communication passage 85 and the sixth communication passage 86B. The fifth communication passage 85 and the sixth communication passage 86B are examples of the “discharge passage” in the present invention.

In addition, a seventh communication passage 89 that extends in the direction diagonal to the front-rear direction is formed in the plate cover 86, and the fourth pressure adjustment chamber 88 and the suction chamber 61A communicate with each other through the seventh communication passage 89.

In this compressor, in the scroll compression part 80 that is accommodated in the suction chamber 61A, the discharge valve chamber 36 and the first discharge portion 39A to which the refrigerant gas is discharged from the compression chamber 55 are located in front of the compression chamber 55. With this configuration, when the first discharge portion 39A is open at the front side thereof and a space in front of the first discharge portion 39A is at the discharge pressure, the thrust load is applied to the scroll compression part 80 by the discharge pressure that is applied to the scroll compression part 80 from the front thereof.

In this regard, in this compressor, an opening of the first discharge portion 39A on the front side thereof is closed by the separation wall 84, and the fourth pressure adjustment chamber 88 is located in front of the separation wall 84. The refrigerant gas at the suction pressure is introduced into this fourth pressure adjustment chamber 88 from the suction chamber 61A through the seventh communication passage 89. The refrigerant gas discharged to the first discharge portion 39A is further discharged to the outside of the housing 60 through the fifth communication passage 85 and the sixth communication passage 86B that extend in the direction intersecting with the thrust direction. With this configuration, the suction pressure is applied to the scroll compression part 80 from the front side and the rear side in the front-rear direction, which is the thrust direction.

Accordingly, even when the refrigerant gas is discharged to the discharge valve chamber 36 and the first discharge portion 39A that are located in front of the compression chamber 55, the thrust load is not applied to the scroll compression part 80 by the discharge pressure in the first discharge portion 39A. As a result, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced.

The present invention has been described above based on the first embodiment to the sixth embodiment. However, the present invention is not limited to the above-described first embodiment to the sixth embodiment, and may be modified as appropriate within the gist of the present invention.

For example, in the compressors of the first embodiment to the sixth embodiment, the scroll compression part 80 is accommodated in the suction chamber 61A, and the suction chamber 61A is used as the scroll accommodating chamber. However, the present invention is not limited thereto, the suction pressure may be applied from the other side in the thrust direction to the scroll compression part that is accommodated in the discharge chamber as the scroll accommodating chamber, and the fluid at the suction pressure may be introduced into the pressure adjustment chamber that is located on the one side in the thrust direction.

In addition, in the compressors of the first embodiment to the sixth embodiment, the driving scroll 30 is supported relative to the housing 60 in the doubly supported manner, and the driven scroll 40 is supported relative to the housing 60 in the cantilever manner. However, the present invention is not limited thereto, both the driving scroll 30 and the driven scroll 40 may be supported relative to the housing 60 in the cantilever manner. When both the driving scroll 30 and the driven scroll 40 are supported relative to the housing 60 in the cantilever manner, the discharge valve mechanism 56 may be provided not in the driving scroll 30 but in the driven scroll 40, and the pressure adjustment chamber may be formed between the driving scroll 30 and the housing 60.

In the compressors of the first embodiment to the fifth embodiment, the fluid at the discharge pressure is introduced into the pressure adjustment chamber from the compression chamber 55; however, the present invention is not limited thereto. A fluid at an intermediate pressure between the suction pressure and the discharge pressure in the middle of compression may be introduced into the pressure adjustment chamber. In addition, the fluid at the discharge pressure or the intermediate pressure may be discharged into the outside of the housing 60 from the compression chamber 55 through the discharge chamber, return to the housing 60 through a tube that is separately provided, and be introduced into the pressure adjustment chamber.

In the compressors of the first embodiment to the fifth embodiment, the suction chamber 61A is separated from the second discharge portion 65A as the discharge chamber by the bearing housing 67 as the first separation wall; however, the present invention is not limited thereto. For example, in the compressors of the first embodiment to the fifth embodiment, the second discharge portion 65A is omitted, and the first discharge portion 39A is directly connected to the discharge communication port 65B, so that the suction chamber 61A may be separated from the outside of the housing 60 by the first separation wall.

In the compressors of the second embodiment and the third embodiment, the second pressure adjustment chamber 79 is formed between the bottom surface of the first annular recess 78, and the distal end surface 641 of the second shaft supporting portion 64 and the front surface 521 of the bottom wall portion 52 of the cover body 35; however, the present invention is not limited thereto, and the second pressure adjustment chamber 79 may be formed only between the bottom surface of the first annular recess 78 and the distal end surface 641 of the second shaft supporting portion 64.

In the compressors of the first embodiment to the sixth embodiment, the suction port 54 is formed in the cover body 35 of the driving scroll 30. However, the present invention is not limited thereto, and the suction port 54 may be formed in the driving scroll end plate 31 of the driving scroll. In the compressor in which the driving scroll 30 and the driven scroll 40 are each supported in the cantilever manner by the housing 60, the suction port may be formed in either the driving scroll end plate 31 or the driven scroll end plate 41.

In the compressors of the first embodiment to the sixth embodiment, in the driving scroll 30, the bearing cover body 34 having the cover portion 38 that covers a part of the discharge valve chamber 36 and a part of the discharge valve mechanism 56 is coupled to the front surface 311 of the driving scroll end plate 31 in which the discharge valve chamber 36 accommodating the discharge valve mechanism 56 is recessed. In addition, the first discharge portion 39A, which is the inner space of the first boss 39 of the bearing cover body 34, communicates with the discharge valve chamber 36. However, the present invention is not limited thereto. The bearing cover body may be omitted, the discharge valve mechanism may be accommodated in the boss protruding integrally from the driving scroll end plate or the driven scroll end plate, and the bearing may be attached to the boss.

In the compressors of the first embodiment to the sixth embodiment, all of the first to third bearings are the sliding bearings; however, the present invention is not limited thereto, and at least one of the first to third bearings may be a rolling bearing.

In the compressor of the fifth embodiment, the thrust bearing 83 is provided between the distal end surface 531 of the second boss 53 and the front surface 631 of the first bottom wall 63; however, the present invention is not limited thereto, for example, the thrust bearing may be provided at the other position to which the thrust load is applied, such as between the distal end surface 92 of the third shaft supporting portion 90 and the bottom surface 75 of the recess 74 and between the bearing cover body 34 of the driving scroll 30 and the first shaft supporting portion 66.

In the compressors of the first embodiment to the sixth embodiment, the driven mechanism 20 is formed of the anti-rotation pins 21 and the rings 22. However, the present invention is not limited thereto, and the driven mechanism 20 may be formed by a pin-ring-pin mechanism in which two pins slides on an inner peripheral surface of one free ring, a pin-and-pin mechanism in which outer peripheral surfaces of two pins slides on each other, a mechanism using an Oldham coupling, or the like.

In the compressors of the first embodiment to the sixth embodiment, the driving scroll 30 is integrated with the rotor 11 by integrating the rotor 11 with the driving scroll peripheral wall 32. However, the present invention is not limited thereto, and the compressor may have a configuration in which the driving scroll 30 is disposed apart from the rotor 11 in the direction where the driving axis R1 extends by connecting the driving scroll 30 to the rotor 11 via a driving shaft so that motive power is transmitted therebetween.

Reference Example

FIG. 8 illustrates a compressor of a reference example. As for the compressor of the reference example, the fourth pressure adjustment chamber 88 that is located in front of the separation wall 84 in the compressor of the sixth embodiment is not formed. Along with this, the seventh communication passage 89 in the compressor of the sixth embodiment is also not formed.

In this compressor, similarly to the compressor of the sixth embodiment, the opening of the first discharge portion 39A on the front side thereof is closed by the separation wall 84, and the first discharge portion 39A and the outside of the housing 60 communicate with each other through the fifth communication passage 85 and the sixth communication passage 86B. The front surface 841 of the separation wall 84 is in contact with the bottom surface 871 of the cylindrical recess 87. Note that the separation wall 84 may be omitted, and the opening of the first discharge portion 39A on the front side thereof may be closed by the bottom surface 871 of the cylindrical recess 87.

In this compressor, the refrigerant gas discharged from the compression chamber 55 to the discharge valve chamber 36 and the first discharge portion 39A is discharged to the outside of the housing 60 through the fifth communication passage 85 and the sixth communication passage 86B.

Thus, a thrust load is not applied to the scroll compression part 80 because of the discharge pressure in the first discharge portion 39A. As a result, the thrust load that is transferred from the scroll compression part 80 to the housing 60 is reduced.

Supplementary Note 1

A co-rotating scroll compressor including:

• • a housing having a suction chamber into which a fluid is sucked from an outside of the co-rotating scroll compressor and a discharge chamber from which the fluid is discharged to the outside of the co-rotating scroll compressor;
  • a first scroll provided in the housing; and
  • a second scroll provided in the housing and facing the first scroll, the second scroll forming, together with the first scroll, a compression chamber in which the fluid is compressed, between the second scroll and the first scroll,
  • the first scroll having a first end plate and a first spiral body that is formed integrally with the first end plate and has a spiral shape protruding toward the second scroll, and
  • the second scroll having a second end plate and a second spiral body that is formed integrally with the second end plate and has a spiral shape protruding toward the first scroll, characterized in that
  • a scroll compression part is formed of the first scroll and the second scroll,
  • a pressure adjustment chamber is formed on one side in a thrust direction of the scroll compression part, and when the fluid at a suction pressure in the suction chamber, a discharge pressure in the discharge chamber, or an intermediate pressure between the suction pressure and the discharge pressure is introduced into the pressure adjustment chamber, the pressure adjustment chamber reduces a thrust load that is applied to the scroll compression part in the thrust direction.

Supplementary Note 2

The co-rotating scroll compressor according to supplementary note 2, characterized in that

• • the suction chamber is a scroll accommodating chamber in which the scroll compression part is accommodated,
  • the discharge pressure is applied to the scroll compression part from the other side in the thrust direction, and
  • the fluid at the discharge pressure or the intermediate pressure is introduced into the pressure adjustment chamber.

Supplementary Note 3

The co-rotating scroll compressor according to supplementary note 2, characterized in that

• • the first scroll has a first shaft supported portion that extends from the first end plate away from the compression chamber, a cover body that faces the first end plate in the thrust direction and is coupled to the first end plate with the second scroll interposed between the first end plate and the cover body, and a second shaft supported portion that extends from the cover body away from the compression chamber,
  • the second scroll has a third shaft supported portion that is formed in the second end plate opposite to the compression chamber,
  • the housing has:
    • a first separation wall that faces the first end plate in the thrust direction and by which the scroll accommodating chamber is defined and a first shaft supporting portion that is formed in the first separation wall; and
    • a second separation wall that faces the cover body in the thrust direction and by which the scroll accommodating chamber is defined and a second shaft supporting portion that is formed in the second separation wall,
  • the housing further has a third shaft supporting portion that is eccentric to the second shaft supporting portion,
  • the first shaft supported portion, the second shaft supported portion, and the third shaft supported portion are supported by the first shaft supporting portion, the second shaft supporting portion, and the third shaft supporting portion via bearings, respectively, and
  • the pressure adjustment chamber is formed between the second end plate and the third shaft supporting portion.

Supplementary Note 4

The co-rotating scroll compressor according to supplementary note 2 or 3, characterized in that

• • the first scroll has a first shaft supported portion that extends from the first end plate away from the compression chamber, a cover body that faces the first end plate in the thrust direction and is coupled to the first end plate with the second scroll interposed between the first end plate and the cover body, and a second shaft supported portion that extends from the cover body away from the compression chamber,
  • the second scroll has a third shaft supported portion that is formed in the second end plate opposite to the compression chamber,
  • the housing has:
    • a first separation wall that faces the first end plate in the thrust direction and by which the scroll accommodating chamber is defined and a first shaft supporting portion that is formed in the first separation wall; and
    • a second separation wall that faces the cover body in the thrust direction and by which the scroll accommodating chamber is defined and a second shaft supporting portion that is formed in the second separation wall,
  • the housing further has a third shaft supporting portion that is eccentric to the second shaft supporting portion,
  • the first shaft supported portion, the second shaft supported portion, and the third shaft supported portion are supported by the first shaft supporting portion, the second shaft supporting portion, and the third shaft supporting portion via bearings, respectively, and
  • the pressure adjustment chamber is formed between the second end plate and the second shaft supporting portion.

Supplementary Note 5

The co-rotating scroll compressor according to supplementary note 2 or 3, characterized in that

• • the first scroll has a first shaft supported portion that extends from the first end plate away from the compression chamber, a cover body that faces the first end plate in the thrust direction and is coupled to the first end plate with the second scroll interposed between the first end plate and the cover body, and a second shaft supported portion that extends from the cover body away from the compression chamber,
  • the second scroll has a third shaft supported portion that is formed in the second end plate opposite to the compression chamber,
  • the housing has:
    • a first separation wall that faces the first end plate in the thrust direction and by which the scroll accommodating chamber is defined and a first shaft supporting portion that is formed in the first separation wall; and
    • a second separation wall that faces the cover body in the thrust direction and by which the scroll accommodating chamber is defined and a second shaft supporting portion that is formed in the second separation wall,
  • the housing further has a third shaft supporting portion that is eccentric to the second shaft supporting portion,
  • the first shaft supported portion, the second shaft supported portion, and the third shaft supported portion are supported by the first shaft supporting portion, the second shaft supporting portion, and the third shaft supporting portion via bearings, respectively, and
  • the pressure adjustment chamber is formed between the cover body and the second separation wall.

Supplementary Note 6

The co-rotating scroll compressor according to supplementary note 1, characterized in that

• • the suction chamber is a scroll accommodating chamber in which the scroll compression part is accommodated,
  • on the one side in the thrust direction of the scroll compression part, the discharge chamber to which the fluid compressed in the compression chamber is discharged is formed and a separation wall that closes an opening of the discharge chamber on the one side is provided,
  • the discharge chamber and the outside of the housing communicate with each other through a discharge passage that extends in a direction intersecting with the thrust direction,
  • the pressure adjustment chamber is formed between an end surface of the separation wall opposite to the discharge chamber and a housing facing surface that faces the end surface, and
  • the fluid at the suction pressure is introduced into the pressure adjustment chamber.

Supplementary Note 7

The co-rotating scroll compressor according to any one of supplementary notes 1 to 6, characterized in that

• • a thrust bearing is provided between the housing and the scroll compression part.

Supplementary Note 8

The co-rotating scroll compressor according to any one of supplementary notes 1 to 7, characterized in that

• • at least one of the bearings is a sliding bearing.

INDUSTRIAL APPLICABILITY

The present invention is applicable to an air conditioner for a vehicle, or the like.

REFERENCE SIGNS LIST

• • 30 driving scroll (first scroll)
  • 31 driving scroll end plate (first end plate)
  • 33 driving scroll spiral body (first spiral body)
  • 35 cover body
  • 36 discharge valve chamber (discharge chamber)
  • 39 first boss (first shaft supported portion)
  • 39A first discharge portion (discharge chamber)
  • 40 driven scroll (second scroll)
  • 41 driven scroll end plate (second end plate)
  • 43 driven scroll spiral body (second spiral body)
  • 53 second boss (second shaft supported portion)
  • 55 compression chamber
  • 60 housing
  • 61A suction chamber (scroll accommodating chamber)
  • 63 first bottom wall (second separation wall)
  • 64 second shaft supporting portion
  • 66 first shaft supporting portion
  • 67 bearing housing (first separation wall)
  • 71 first sliding bearing (bearing, sliding bearing)
  • 72 second sliding bearing (bearing, sliding bearing)
  • 73 third sliding bearing (bearing, sliding bearing)
  • 74 recess (third shaft supported portion)
  • 76 first pressure adjustment chamber (pressure adjustment chamber)
  • 79 second pressure adjustment chamber (pressure adjustment chamber)
  • 80 scroll compression part
  • 83 thrust bearing
  • 84 separation wall
  • 841 front surface (end surface)
  • 85 fifth communication passage (discharge passage)
  • 86 plate cover (first separation wall)
  • 86B sixth communication passage (discharge passage)
  • 871 bottom surface (housing facing surface)
  • 87A increased diameter recess (first shaft supporting portion)
  • 88 fourth pressure adjustment chamber (pressure adjustment chamber)
  • 90 third shaft supporting portion
  • 96 third pressure adjustment chamber (pressure adjustment chamber)