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.

Citation List

Patent Literature

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

SUMMARY OF INVENTION

Technical Problem

Here, in the co-rotating scroll compressor, a pair of bearings are disposed with the driving scroll and the driven scroll interposed therebetween. The driving scroll is rotatably supported by a driving side bearing of the bearings and the driven scroll is rotatably supported by a driven side bearing of the bearings.

However, in the above-described conventional co-rotating scroll compressor, a boss portion having a cylindrical shape is formed integrally with an outer end surface of the driven scroll end plate oppose to the compression chamber, and protrudes from the outer end surface. The driven side bearing is attached to an outer peripheral surface of such a boss portion. In addition, a discharge port through which the fluid is discharged from the compression chamber is formed in the driven scroll end plate, and a discharge vale that opens and closes the discharge port is provided inside the boss portion.

With this configuration, in the above-described conventional co-rotating scroll compressor, the discharge valve is provided inside the boss portion. However, since an inner diameter of the boss portion is greater than a length of the longest portion of the discharge valve, an increase in size of the boss portion and the bearing that is attached to the boss portion cannot be avoided. When the bearing increases in size, a sliding distance per rotation increases, which increases a required power. This causes concerns about noise, vibrations, and compression efficiency.

The present invention is made in view of the above-described circumstances, and is directed to providing a co-rotating scroll compressor in which noise, vibrations, and a decrease of compression efficiency are suppressed by preventing an increase in size of a bearing for rotatably supporting a scroll in which a discharge valve is provided, relative to a housing.

Solution to Problem

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

• • a housing having 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;
  • 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, wherein
  • the first scroll has a bearing cover body that is fixed to an end surface of the first end plate opposite to the compression chamber,
  • a discharge valve chamber that is a part of the discharge chamber is formed between the first end plate and the bearing cover body,
  • a discharge port through which the compression chamber and the discharge valve chamber communicate with each other is formed in the first end plate,
  • a discharge valve that opens and closes the discharge port is provided in the discharge valve chamber,
  • the bearing cover body has:
    • a cover portion that covers a part of the discharge valve chamber and a part of the discharge valve; and
    • a boss portion that has a cylindrical shape extending from an inner peripheral portion of the cover portion opposite to the compression chamber and has an inner space communicating with the discharge valve chamber, and
  • a bearing that rotatably supports the first scroll is provided on an outer peripheral surface of the boss portion.

In the co-rotating scroll compressor of the present invention, the bearing cover body is fixed to the end surface of the first end plate opposite to the compression chamber. In addition, the discharge valve chamber that is a part of the discharge chamber is formed between the first end plate and the bearing cover body, and the discharge port through which the compression chamber and the discharge valve chamber communicate with each other is formed in the first end plate. The discharge valve that opens and closes the discharge port is provided in the discharge valve chamber.

The bearing cover body has the cover portion and the boss portion. The cover portion covers a part of the discharge valve chamber and a part of the discharge valve. The inner space of the boss portion communicates with the discharge valve chamber. Thus, the fluid compressed in the compression chamber is discharged to the discharge chamber including the discharge valve chamber and the inner space of the boss portion through the discharge port. The bearing is provided on the outer peripheral surface of the boss portion.

Here, in the above-described conventional compressor in which the discharge valve is accommodated in the inner space of the boss portion, the inner space of the boss portion is necessarily larger than the discharge valve. In this regard, in the co-rotating scroll compressor of the present invention in which the discharge valve chamber in which the discharge valve is accommodated is formed between the bearing cover body having the boss portion and the first end plate, the inner space of the boss portion is designed regardless of a size of the discharge valve.

Accordingly, in this co-rotating scroll compressor, the boss portion may be made smaller than that of the above-described conventional compressor in which the inner space of the boss portion is necessarily larger than the discharge valve. As a result, the bearing that is provided on the outer circumferential surface of the boss portion may also be made smaller.

Therefore, in the co-rotating scroll compressor of the present invention, noise, vibrations, and a decrease of compression efficiency are suppressed by preventing an increase in size of the bearing for rotatably supporting the scroll in which the discharge valve is provided, relative to the housing.

The discharge valve is preferably a discharge reed valve having a valve distal portion that opens and closes the discharge port and a valve fixed proximal end portion at which the discharge valve is fixed to the first end plate. The valve fixed proximal end portion is preferably covered by the cover portion.

In this case, even when bolts for fixing the valve fixed proximal end portion, or the like become loose, the cover portion may suppress that the bolts fall off.

The valve distal portion is preferably located close to a center of the boss portion compared to the valve fixed proximal end portion.

In this case, since the valve distal portion is located near the center of the boss portion, the discharge port that is opened and closed by the valve distal portion is also located near the center of the boss portion. The center of the boss portion on which the bearing of the first scroll is provided is also a center of rotation of the first scroll. With this configuration, the fluid further compressed in the compression chamber is discharged through the discharge port, which is advantageous in improving the compression efficiency.

The co-rotating scroll compressor in the present invention preferably has the following configuration. At least the first end plate of the first end plate and the second end plate has: a protruding portion that protrudes toward the first end plate facing the second end plate or the second end plate facing the first end plate, a non-protruding portion that is located outside the protruding portion; and an end plate stepped portion that connects the protruding portion and the non-protruding portion, and each of the first spiral body that protrudes from the first end plate facing the second end plate and the second spiral body that protrudes from the second end plate facing the first end plate has: a spiral main body portion; a spiral short portion that protrudes shorter than the spiral main body portion so that interference of the spiral short portion with the protruding portion is avoidable; and a spiral body stepped portion that connects the spiral main body portion and the spiral short portion, and the discharge valve chamber is formed of a recess that is located in a region where the protruding portion is formed and is recessed in the end surface of the first end plate toward the compression chamber.

In this case, in the first end plate, the discharge valve chamber is formed in the region where the protruding portion is formed. This first end plate has the non-protruding portion that is located outside of the protruding portion, and only a part of the first end plate is made thicker. Thus, it is suppressed that the first end plate increases in weight as compared with a case where the first end plate is entirely made thick in order to form the discharge valve chamber. In addition, a distance between the first end plate on which the protruding portion is formed and the second end plate on which the protruding portion is formed is shorter than a distance between the first end plate on which the protruding portion is not formed and the second end plate on which the protruding portion is not formed, so that a volume of the compression chamber defined between the first end plate and the second end plate may be decreased as much as only a difference of these distances and the compression efficiency may be improved.

The co-rotating scroll compressor in the present invention preferably further includes an oil returning passage that is opened in an inner peripheral surface of the discharge valve chamber and extends outward from the inner peripheral surface of the discharge valve chamber and through which the discharge valve chamber and the suction chamber or the compression chamber communicate with each other.

In this case, since the discharge valve chamber rotates during operation of the compressor, a centrifugal force acts on the fluid discharged to the discharge valve chamber through the discharge port. This separates oil from the fluid. Then, the oil separated from the fluid is subjected to the centrifugal force in the discharge valve chamber to flow outward. In addition, a part of the discharge valve chamber is covered by the cover portion, so that the cover portion blocks most of the oil flowing out from the discharge valve chamber toward the inner space of the boss portion.

Accordingly, the oil in the discharge valve chamber is easily introduced into the oil returning passage that is opened in the inner peripheral surface of the discharge valve chamber. The oil introduced into the oil returning passage is subjected to the centrifugal force to flow outward, and then, flows into the suction chamber. The oil that has flowed into the suction chamber contributes to oil lubrication and oil sealing at portions where lubrication and sealing properties are required.

Advantageous Effects of Invention

In the co-rotating scroll compressor according to the present invention, noise, vibrations, and a decrease of compression efficiency are suppressed by preventing an increase in size of the bearing for rotatably supporting the scroll in which the discharge valve is provided, relative to the housing.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view of a co-rotating scroll compressor according to 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 a partial cross-sectional view illustrating a second boss of a bearing cover body according to the co-rotating scroll compressor of the first embodiment.

FIG. 4 is an exploded perspective view illustrating a driven scroll main body, a gasket, and the bearing cover body as viewed from a front side thereof, according to the co-rotating scroll compressor of the first embodiment.

FIG. 5 is a perspective view illustrating the driven scroll main body as viewed from the front side thereof, according to the co-rotating scroll compressor of the first embodiment.

FIG. 6 is a partial front view illustrating a discharge valve chamber in the driven scroll main body as viewed from a front side of the discharge valve chamber, according to the co-rotating scroll compressor of the first embodiment.

FIG. 7 is a view for explanation of a driving scroll end plate and a driving scroll spiral body as viewed from a front side of a driving scroll, according to the co-rotating scroll compressor of the first embodiment.

FIG. 8 is a view for explanation of a driven scroll end plate and a driven scroll spiral body as viewed from a front side of a driven scroll, according to the co-rotating scroll compressor of the first embodiment.

FIG. 9 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. 10 is a partial front view illustrating a discharge valve chamber in a driven scroll main body as viewed from a front side of the discharge valve chamber, according to the co-rotating scroll compressor of the second embodiment.

DESCRIPTION OF EMBODIMENTS

The following will describe a first embodiment and a second 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, an electric motor 10, an inverter circuit 70, 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 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 “first scroll”, the “first end plate”, the “first spiral body” in the present invention, respectively. Furthermore, 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 “second scroll”, the “second end plate”, and the “second spiral body” in the present invention, respectively.

The housing 60 is formed of a housing main body 61, a cover 65, and an inverter case 67. The housing main body 61 is a bottomed tubular member having a first outer peripheral wall 62 and a first bottom wall 63. 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 main 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 shaft supporting portion 64 having a columnar shape protrudes forward from a center of an inner surface of the first bottom wall 63. The shaft supporting portion 64 is fitted into an inner ring of the bearing 71.

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

A shaft supporting portion 66 having a cylindrical shape extending around a driven axis R2 protrudes from a center of an inner surface of the cover 65. 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 in parallel to the front-rear direction. An outer ring of a needle bearing 72 is fitted into the shaft supporting portion 66. The needle bearing 72 is an example of the “bearing” in the present invention.

The cover 65 has a suction communicating port 65A, a discharge communicating port 65B, and a discharge portion 65C. The suction communicating port 65A is located between the outer peripheral edge of the cover 65 and the shaft supporting portion 66 and extends through the cover 65 in parallel to the driving axis R1. The suction chamber 61A and an outside of the compressor communicate with each other through the suction communicating port 65A. A tube is connected to the suction communicating port 65A. 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.

The discharge portion 65C is recessed in a rear surface 651 of the cover 65 at a center thereof. The discharge communicating port 65B extends through the cover 65 in parallel to the driving axis R1 so as to communicate with the discharge portion 65C. A tube, which is not illustrated, is connected to the discharge communicating port 65B, and the refrigerant gas discharged to the discharge portion 65C flows toward a condenser through the discharge communicating port 65B and the tube. Note that illustrations of the tubes, the evaporator, and the condenser are omitted.

The inverter case 67 is disposed behind the housing main body 61. The inverter case 67 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 rear end of the inverter case 67. The second bottom wall 69 is formed in 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 rear end of the second outer peripheral wall 68.

The inverter case 67 is fastened to the first bottom wall 63 by bolts, which are not illustrated, with a front end of the second outer peripheral wall 68 in contact with a rear surface of the first bottom wall 63. With this configuration, the inverter case 67 cooperates with the first bottom wall 63 to form an inverter chamber 67A therebetween. The inverter chamber 67A is located adjacent to and behind the suction chamber 61A. In addition, the inverter chamber 67A is separated from the suction chamber 61A by the first bottom wall 63. Note that a connector portion is formed in the inverter case 67 although not illustrated.

The electric motor 10 is accommodated in the suction chamber 61A. Accordingly, the suction chamber 61A also serves as a motor chamber in which the electric motor 10 is accommodated. The electric motor 10 includes a 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 main body 61, so that the stator 17 is fixed to the housing main 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 inverter circuit 70 is accommodated in the inverter chamber 67A. The inverter circuit 70 is formed of a circuit board 70A, and switching elements 70B or the like mounted on the circuit board 70A. In the inverter circuit 70, the circuit board 70A is fixed to the rear surface of the first bottom wall 63 by bolts which are not illustrated. The inverter circuit 70 is electrically connected to a battery, which is not illustrated, of the vehicle through a connector provided in the inverter case. Furthermore, the inverter circuit 70 is electrically connected to the stator 17 through a hermetic passage, which is not illustrated, formed in the first bottom wall 63. With the connection, the inverter circuit 70 converts DC current supplied from the battery to AC current and supplies its power to the stator 17.

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

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 first boss 34 that protrudes toward the first bottom wall 63 is formed in a center of the rear surface 312. The first boss 34 is formed in a cylindrical shape extending around the driving axis R1.

The driving scroll end plate 31 has a suction port 35. The suction port 35 is disposed outside the first boss 34. The suction port 35 is located far away from the driving axis R1 compared to the first boss 34 in a radial direction of the driving scroll end plate 31. The suction port 35 is formed in a substantially elliptical shape extending in a circumferential direction of the driving scroll end plate 31. As illustrated in FIG. 1, the suction port 35 extends through the driving scroll end plate 31 in a direction in which the driving axis R1 extends, that is, in the front-rear direction. Note that the shape of the suction port 35 and the number of the suction ports 35 may be designed as appropriate.

The driving scroll peripheral wall 32 is formed integrally with the driving scroll end plate 31 and extends in parallel to the driving axis R1 from an outer peripheral edge of the driving scroll end plate 31 forward, that is, toward the driven scroll 40. As illustrated in FIG. 7, the driving scroll peripheral wall 32 is formed in a substantially cylindrical shape extending around the driving axis R1. Four fixing holes 32A are formed in a front end of the driving scroll peripheral wall 32. Note that two of the four fixing holes 32A are illustrated in FIG. 1.

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. As illustrated in FIG. 1, the driving scroll spiral body 33 extends forward in parallel to the driving axis R1 from the front surface 311 of the driving scroll end plate 31. As illustrated in FIG. 7, 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.

As illustrated in FIG. 4, the driven scroll 40 is formed of a driven scroll main body 40A, a bearing cover body 40B, and a gasket 40C. The driven scroll main body 40A 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 the driven axis R2. The driven scroll end plate 41 has a front surface 411 and a rear surface 412 located opposite the front surface 411. The front surface 411 corresponds to the “end surface of the first end plate oppose to the compression chamber”.

A discharge valve chamber 44 is formed in the driven scroll end plate 41 and opened in the front surface 411 of the driven scroll end plate 41. The discharge valve chamber 44 is formed of a recess 50 that is partially recessed in the front surface 411 toward a compression chamber 55, which will be described later, and defined by a recess bottom surface 50A and a recess inner peripheral surface 50B. As illustrated in FIGS. 2 and 5, the recess 50 is formed of a first recess 51, a second recess 52, and a third recess 53. The first recess 51, the second recess 52, and the third recess 53 are deeper in this order. That is, the first recess 51 is shallowest, and the third recess 53 is deepest.

As illustrated in FIGS. 2 and 6, the recess bottom surface 50A of the recess 50 has a first recess bottom surface 51A, a second recess bottom surface 52A, and a third recess bottom surface 53A. The recess inner peripheral surface 50B of the recess 50 has a first recess inner peripheral surface 51B, a second recess inner peripheral surface 52B, and a third recess inner peripheral surface 53B. The first recess 51 is defined by the first recess bottom surface 51A and the first recess inner peripheral surface 51B. The second recess 52 is defined by the second recess bottom surface 52A and the second recess inner peripheral surface 52B. The third recess 53 is defined by the third recess bottom surface 53A and the third recess inner peripheral surface 53B.

The first recess inner peripheral surface 51B is formed in a circular shape, and the first recess 51 has a circular outer shape extending around the driven axis R2. An outer shape of the third recess 53 substantially corresponds to an outer shape of a discharge valve mechanism 56, and a depth of the third recess 53 is slightly greater than a thickness of the discharge valve mechanism 56. That is, the third recess 53 is designed so as to have a size that accommodates the discharge valve mechanism 56. In the first recess 51 having the circular shape, the third recess 53 is located at a position on one side relative to the driven axis R2, and the second recess 52 extends from an outer edge of the third recess 53 toward the other side relative to the driven axis R2.

A discharge port 45 is formed in the driven scroll end plate 41 and extends through the driven scroll end plate 41 in the front-rear direction. The discharge port 45 is, at one end thereof, opened to the compression chamber 55, which will be described later. The discharge port 45 is, at the other end thereof, opened in the third recess bottom surface 53A. That is, the compression chamber 55 and the discharge valve chamber 44 communicate with each other through the discharge port 45.

As illustrated in FIGS. 2 and 6, or the like, the discharge valve mechanism 56 is disposed in the discharge valve chamber 44. In detail, the discharge valve mechanism 56 is disposed in the third recess 53 of the recess 50 that forms the discharge valve chamber 44. Note that the discharge valve mechanism 56 is illustrated by a long dashed double dotted line in FIG. 6.

The discharge valve mechanism 56 has a discharge reed valve 57, a retainer 58, and bolts 59. The discharge reed valve 57 is an example of the “discharge valve” in the present invention. The discharge reed valve 57 and the retainer 58 are fixed to the third recess bottom surface 53A by the bolts 59. The discharge reed valve 57 is capable of opening and closing the discharge port 45. Furthermore, an opening degree of the discharge reed valve 57 is adjustable by the retainer 58.

As illustrated in FIG. 6, the discharge reed valve 57 has a valve distal portion 57A and a valve fixed proximal end portion 57B. The valve distal portion 57A is disposed near the driven axis R2, and opens and closes the discharge port 45. More specifically, in the front-rear direction, the driven axis R2 is located inside an outer edge of the valve distal portion 57A. The valve fixed proximal end portion 57B is fixed to the third recess bottom surface 53A by the bolts 59. As illustrated in FIGS. 2 and 6, the discharge port 45 is located near the driven axis R2, and the valve fixed proximal end portion 57B is located at a predetermined distance away from the driven axis R2. That is, the valve distal portion 57A that opens and closes the discharge port 45 is located close to the driven axis R2 compared to the valve fixed proximal end portion 57B. In other words, the valve distal portion 57A is located close to a center of a second boss 48, which will be described later, compared to the valve fixed proximal end portion 57B.

As illustrated in FIGS. 2 and 6, an oil returning passage 54 is formed in the driven scroll end plate 41. The oil returning passage 54 has a groove portion 541 that is recessed in the front surface 411 of the driven scroll end plate 41 and a hole portion 542 that extends through the driven scroll end plate 41 in the front-rear direction.

The groove portion 541 is, at one end on an inner peripheral side of the groove portion 541, opened in the first recess inner peripheral surface 51B. The groove portion 541 extends straight from the one end on the inner peripheral side of the groove portion 541 outward. The groove portion 541 is, at the other end on an outer peripheral side thereof, connected to a front end of the hole portion 542. The hole portion 542 extends straight in the front-rear direction. The hole portion 542 whose front end is connected to the other end of the groove portion 541 is, at a rear end of the hole portion 542, opened in the rear surface 412 of the driven scroll end plate 41. This position at which the hole portion 542 is opened is located within the suction chamber 61A. More specifically, the hole portion 542 is opened at a position outside the driven scroll spiral body 43 and just outside a starting portion of the compression chamber 55 from which the compression chamber 55, which will be described later, starts to be closed for the compression. Thus, the discharge valve chamber 44 and the suction chamber 61A communicate with each other through the oil returning passage 54. The first recess inner peripheral surface 51B in which the oil returning passage 54 described below is opened is an example of the “inner peripheral surface of the discharge valve chamber” in the present invention.

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 rear surface 412 of the driven scroll end plate 41 rearward, that is, toward the driving scroll 30. As illustrated in FIG. 8, 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 side of the driven scroll spiral body 43.

As illustrated in FIG. 1, 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 fixing holes 32A formed in the driving scroll peripheral wall 32. Thus, the anti-rotation pins 21 are fixed to the driving scroll peripheral wall 32 so that the anti-rotation pins 21 extend out forward over the driving scroll peripheral wall 32.

The rings 22 are formed in the driven scroll end plate 41 so as to face the corresponding anti-rotation pins 21. The rings 22 are fitted into bottomed circular holes which are recessed in the rear surface 412 of the driven scroll end plate 41.

The gasket 40C is formed in a circular plate shape and has a communication port 46 at a center of the gasket 40C. A diameter of the communication port 46 is set to the same diameter as an inner diameter d of the second boss 48, which will be described later. The gasket 40C is held between the front surface 411 of the driven scroll end plate 41 and a rear surface 472 of a cover portion 47, which will described later, to provide a seal between the driven scroll end plate 41 and the cover portion 47.

The bearing cover body 40B has the cover portion 47 and the second boss 48 formed integrally with the cover portion 47. The second boss 48 corresponds to the “boss portion” in the present invention.

The cover portion 47 is formed in a substantially circular plate shape extending perpendicularly to the driven axis R2. The cover portion 47 has a front surface 471 and the rear surface 472 located opposite the front surface 471. The cover portion 47 has, at a center thereof, a through hole 47A. The second boss 48 protrudes forward from an inner peripheral edge of the cover portion 47, that is, a center of the front surface 471 of the cover portion 47. The second boss 48 is formed in a cylindrical shape extending in a direction in which the driven axis R2 extends, around the driven axis R2. The inner diameter d of a columnar inner space 48A of the second boss 48 and an outer diameter D of the second boss 48 are each less than a length L (see FIGS. 3 and 6) of the longest portion of the discharge reed valve 57. Note that in a plan view as viewed in the front-rear direction, an outer edge of the inner space 48A of the second boss 48 is located inside the outer edge of the third recess 53, that is, inside the third recess inner peripheral surface 53B. In addition, in this compressor, a discharge chamber is formed of the discharge valve chamber 44, the inner space 48A, and the discharge portion 65C.

As illustrated in FIG. 4, four bolt insertion holes 49 are formed in outer peripheral edge portions of the driven scroll end plate 41 of the driven scroll main body 40A, the gasket 40C, and the cover portion 47 of the bearing cover body 40B. The driven scroll main body 40A and the bearing cover body 40B are integrally coupled to each other by bolts that are inserted through the bolt insertion holes 49 and not illustrated with the gasket 40C interposed therebetween. Note that the driven scroll main body 40A and the bearing cover body 40B are coupled to each other after the discharge valve mechanism 56 is disposed in the discharge valve chamber 44, and subsequently, the discharge reed valve 57 and the retainer 58 are fixed to the third recess bottom surface 53A by the bolts 59.

In a state where the bearing cover body 40B is coupled to the driven scroll main body 40A, a large part of the discharge valve chamber 44 and a large part of the discharge valve mechanism 56 are covered by the cover portion 47 of the bearing cover body 40B. More specifically, in the recess 50 that forms the discharge valve chamber 44, the entire first recess 51, the entire second recess 52, and a part of the third recess 53 are covered by the cover portion 47.

In this compressor, the driving scroll 30 and the driven scroll 40 are both disposed in the suction chamber 61A. The driving scroll peripheral wall 32 is fixed to an inner peripheral surface of the rotor 11, so that the driving scroll 30 is integrated with the rotor 11. In addition, an outer ring of a bearing 71 is fitted into the first boss 34 in the driving scroll 30. With this configuration, the driving scroll 30 is supported by the housing main body 61 so as to be rotatable around the driving axis R1. Here, in this compressor, the driving scroll 30 is supported at a so-called only one end of the driving scroll 30 by the housing main body 61, and by extension, the housing 60.

On the other hand, the driven scroll 40 is disposed in front of the driving scroll 30 with the driven scroll spiral body 43 facing the driving scroll 30. With this configuration, the front surface 311 of the driving scroll end plate 31 faces the rear surface 412 of the driven scroll end plate 41 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 driving scroll 30 and the driven scroll 40 are assembled to 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 second boss 48 is fitted into an inner ring of the needle bearing 72 so that an outer peripheral surface of the second boss 48 is in contact with the inner ring of the needle bearing 72. With this configuration, the driven scroll 40 is supported by the cover 65 so as to be rotatable around the driven axis R2. Here, in this compressor, the driven scroll 40 is also supported at a so-called only one end of the driven scroll 40 by the cover 65, and by extension, the housing 60.

The driven scroll 40 is supported by the cover 65, so that the inner space 48A of the second boss 48 faces the discharge portion 65C in the front-rear direction. Furthermore, the discharge port 45 and the valve distal portion 57A of the discharge reed valve 57 are located near the driven axis R2.

In this compressor, as illustrated in FIG. 7, the driving scroll end plate 31 of the driving scroll 30 has a driving scroll protruding portion 31A, a driving scroll non-protruding portion 31B, and a driving scroll end plate stepped portion 31C. The driving scroll protruding portion 31A, the driving scroll non-protruding portion 31B, and the driving scroll end plate stepped portion 31C correspond to the “protruding portion”, the “non-protruding portion”, and the “end plate stepped portion” in the present invention, respectively. In addition, the driving scroll spiral body 33 of the driving scroll 30 has a driving scroll spiral short portion 33A, a driving scroll spiral main body portion 33B, and a driving scroll spiral body stepped portion 33C. The driving scroll spiral short portion 33A, the driving scroll spiral main body portion 33B, and the driving scroll spiral body stepped portion 33C correspond to the “spiral short portion”, the “spiral main body portion”, and the “spiral body stepped portion” in the present invention, respectively.

Similarly, as illustrated in FIG. 8, the driven scroll end plate 41 of the driven scroll 40 has a driven scroll protruding portion 41A, a driven scroll non-protruding portion 41B, and a driven scroll end plate stepped portion 41C. The driven scroll protruding portion 41A, the driven scroll non-protruding portion 41B, and the driven scroll end plate stepped portion 41C correspond to the “protruding portion”, the “non-protruding portion”, and the “end plate stepped portion” in the present invention, respectively. In addition, the driven scroll spiral body 43 of the driven scroll 40 has a driven scroll spiral short portion 43A, a driven scroll spiral main body portion 43B, and a driven scroll spiral body stepped portion 43C. The driven scroll spiral short portion 43A, the driven scroll spiral main body portion 43B, and the driven scroll spiral body stepped portion 43C correspond to the “spiral short portion”, the “spiral main body portion”, and the “spiral body stepped portion” in the present invention, respectively.

As illustrated in FIG. 7, the driving scroll protruding portion 31A is formed on the front surface 311 of the driving scroll end plate 31. The driving scroll protruding portion 31A extends in a right-handed spiral manner, starting from a center portion of the front surface 311, that is, a portion of the front surface 311 close to the driving axis R1 and a portion of the front surface 311 close to the center of the spiral of the driving scroll spiral body 33, toward an outer periphery of the front surface 311 along the driving scroll spiral body 33. As illustrated in FIG. 1, the driving scroll protruding portion 31A further protrudes toward the driven scroll spiral body 43 compared to the driving scroll non-protruding portion 31B, which is a portion excluding the driving scroll protruding portion 31A in the driving scroll end plate 31. That is, the driving scroll protruding portion 31A is formed to be thicker than the driving scroll non-protruding portion 31B. The driving scroll non-protruding portion 31B is located outside the driving scroll protruding portion 31A in the driving scroll end plate 31.

As illustrated in FIG. 7, the driving scroll end plate stepped portion 31C is formed at a boundary between the driving scroll protruding portion 31A and the driving scroll non-protruding portion 31B and connected to the driving scroll protruding portion 31A and the driving scroll non-protruding portion 31B. Note that a length of the driving scroll protruding portion 31A extending toward the outer periphery of the front surface 311, that is, a position at which the driving scroll end plate stepped portion 31C is formed, may be designed as appropriate.

On the other hand, as illustrated in FIG. 1, the driven scroll protruding portion 41A is formed on the rear surface 412 of the driven scroll end plate 41. As illustrated in FIG. 8, the driven scroll protruding portion 41A extends in a right-handed spiral manner, starting from a center portion of the rear surface 412, that is, a portion of the rear surface 412 close to the driven axis R2 and a portion of the rear surface 412 close to the center of the spiral of the driven scroll spiral body 43, toward an outer periphery of the rear surface 412 along the driven scroll spiral body 43. As illustrated in FIG. 1, the driven scroll protruding portion 41A further protrudes toward the driving scroll spiral body 33 compared to the driven scroll non-protruding portion 41B, which is a portion excluding the driven scroll protruding portion 41A in the driven scroll end plate 41. That is, the driven scroll protruding portion 41A is formed to be thicker than the driven scroll non-protruding portion 41B. The driven scroll non-protruding portion 41B is located outside the driven scroll protruding portion 41A in the driven scroll end plate 41.

As illustrated in FIG. 8, the driven scroll end plate stepped portion 41C is formed at a boundary between the driven scroll protruding portion 41A and the driven scroll non-protruding portion 41B and connected to the driven scroll protruding portion 41A and the driven scroll non-protruding portion 41B. Note that a length of the driven scroll protruding portion 41A extending toward the outer periphery of the rear surface 412, that is, a position at which the driven scroll end plate stepped portion 41C is formed may be designed as appropriate.

The discharge port 45 is opened in the driven scroll protruding portion 41A. As illustrated in FIG. 2, the driven scroll protruding portion 41A and the discharge valve mechanism 56 are overlapped with each other in the front-rear direction, that is, in the direction in which the driven axis R2 extends. That is, the second recess 52 and the third recess 53 of the recess 50 that forms the discharge valve chamber 44 are disposed in a region corresponding to the driven scroll protruding portion 41A. More specifically, in the plan view as viewed in the front-rear direction, an outer edge of the second recess 52 and the outer edge of the third recess 53 are located inside an outer edge of the driven scroll protruding portion 41A.

As illustrated in FIG. 7, the driving scroll spiral short portion 33A extends from the center of the spiral of the driving scroll spiral body 33 toward an outer periphery of the spiral. As illustrated in FIG. 1, when the driving scroll 30 is assembled to the driven scroll 40 in the front-rear direction, the driving scroll spiral short portion 33A faces the driven scroll protruding portion 41A. Here, a length of the driving scroll spiral short portion 33A extending toward the driven scroll end plate 41, that is, the length in the direction in which the driving axis R1 extends, is less than a length of the driving scroll spiral main body portion 33B in the direction in which the driving axis R1 extends, which is a portion excluding the driving scroll spiral short portion 33A in the driving scroll spiral body 33.

In other words, the driving scroll spiral main body portion 33B is a portion having the longest length in the driving scroll spiral body 33 extending toward the driven scroll end plate 41. Accordingly, the driving scroll spiral short portion 33A is shorter in the direction in which the driving axis R1 extends than the portion having the longest length in the driving scroll spiral body 33 extending toward the driven scroll end plate 41. This prevents the driving scroll spiral short portion 33A from interfering with the driven scroll protruding portion 41A.

As illustrated in FIG. 7, the driving scroll spiral body stepped portion 33C is formed at a boundary between the driving scroll spiral short portion 33A and the driving scroll spiral main body portion 33B and connected to the driving scroll spiral short portion 33A and the driving scroll spiral main body portion 33B.

As illustrated in FIG. 8, the driven scroll spiral short portion 43A extends from the center of the spiral of the driven scroll spiral body 43 toward an outer periphery of the spiral. As illustrated in FIG. 1, when the driving scroll 30 is assembled to the driven scroll 40 in the front-rear direction, the driven scroll spiral short portion 43A faces the driving scroll protruding portion 31A. Here, a length of the driven scroll spiral short portion 43A extending toward the driving scroll end plate 31, that is, the length in the direction in which the driven axis R2 extends, is less than a length of the driven scroll spiral main body portion 43B in the direction in which the driven axis R2 extends, which is a portion excluding the driven scroll spiral short portion 43A in the driven scroll spiral body 43.

In other words, the driven scroll spiral main body portion 43B is a portion having the longest length in the driven scroll spiral body 43 extending toward the driving scroll end plate 31. Accordingly, the driven scroll spiral short portion 43A is shorter in the direction in which the driven axis R2 extends than the portion having the longest length in the driven scroll spiral body 43 extending toward the driving scroll end plate 31. This prevents the driven scroll spiral short portion 43A from interfering with the driving scroll protruding portion 31A.

As illustrated in FIG. 8, the driven scroll spiral body stepped portion 43C is formed at a boundary between the driven scroll spiral short portion 43A and the driven scroll spiral main body portion 43B and connected to the driven scroll spiral short portion 43A and the driven scroll spiral main body portion 43B.

In this compressor having the configuration described above, while the inverter circuit 70 supplies power to the stator 17, the inverter circuit 70 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 and the rotor 11 rotate integrally with each other. 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.

As a result, the refrigerant gas in the suction chamber 61A is sucked into the compression chamber 55 through the suction port 35, 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 44 through the discharge port 45. After that, the refrigerant gas is discharged to the discharge portion 65C through the inner space 48A of the second boss 48, and then, discharged to the condenser through the discharge communicating port 65B. Thus, an air conditioning by the air conditioner for the vehicle is performed.

Here, in this compressor, the driven scroll 40 has the driven scroll main body 40A and the bearing cover body 40B. The discharge valve chamber 44 in which the discharge valve mechanism 56 is accommodated is formed in the driven scroll end plate 41 of the driven scroll main body 40A. The bearing cover body 40B has the cover portion 47 that covers a large part of the discharge valve chamber 44 and a large part of the discharge valve mechanism 56 and the second boss 48 to which the needle bearing 72 is attached, and the discharge valve chamber 44 and the discharge portion 65C communicate with each other through the inner space 48A of this second boss 48.

With this configuration, in this compressor, the discharge valve mechanism 56 is not accommodated in the inner space 48A of the second boss 48, so that there is no need to make the inner space 48A of the second boss 48 larger than the discharge valve mechanism 56. Accordingly, this compressor has the boss that is formed integrally with the driven scroll end plate and to which the driven scroll side bearing for rotatably supporting the driven scroll relative to the housing is attached. In addition, in this compressor, the inner space 48A of the second boss 48 may be decreased in size, compared to the above-described conventional compressor in which the discharge valve is accommodated in this boss. As a result, the inner diameter d of the inner space 48A of the second boss 48 and the outer diameter D of the second boss 48 are less than the length L of the longest portion of the discharge reed valve 57. Thus, the needle bearing 72 that is attached to the outer peripheral surface of the second boss 48 may be decreased in size, compared to a needle bearing used in the conventional compressor.

Therefore, in the compressor of the embodiment, the needle bearing 72, which is a bearing for rotatably supporting the driven scroll 40 in which the discharge valve mechanism 56 is provided relative to the housing 60, is prevented from increasing in size, so that noise, vibrations, and a decrease in compression efficiency are suppressed.

In this compressor, the valve fixed proximal end portion 57B of the discharge reed valve 57 is covered by the cover portion 47. With this configuration, even when the bolts 59 become loose, the cover portion 47 may suppress that the bolts 59 fall off. In addition, the valve distal portion 57A of the discharge reed valve 57 is located near the driven axis R2, and the discharge port 45 that is opened and closed by the valve distal portion 57A is also located near the driven axis R2. With this configuration, the fluid further compressed in the compression chamber 55 is discharged through the discharge port 45, which is advantageous in improving the compression efficiency.

In this compressor, the driving scroll protruding portion 31A is formed on the driving scroll end plate 31 of the driving scroll 30, and the driven scroll protruding portion 41A and the driven scroll non-protruding portion 41B, which is thinner than the driven scroll protruding portion 41A, are formed on the driven scroll end plate 41 of the driven scroll 40. The second recess 52 and the third recess 53 of the recess 50 that forms the discharge valve chamber 44 are disposed in the region corresponding to the driven scroll protruding portion 41A of the driven scroll end plate 41, and the outer edges of the second recess 52 and the third recess 53 are located inside the outer edge of the driven scroll protruding portion 41A.

With this configuration, in this compressor, only a part of the driven scroll end plate 41 is made thick, so that it is suppressed that the driven scroll end plate 41 increases in weight as compared with a case where the driven scroll end plate 41 is entirely made thick in order to form the discharge valve chamber 44. A distance between the driven scroll protruding portion 41A and the driving scroll protruding portion 31A is shorter than a distance between the driven scroll end plate on which the driven scroll protruding portion 41A is not formed and the driving scroll end plate on which the driving scroll protruding portion 31A is not formed, so that the volume of the compression chamber 55 defined between the driven scroll protruding portion 41A and the driving scroll protruding portion 31A may be decreased as much as only a difference of these distances and the compression efficiency may be improved.

In this compressor, the discharge port 45 is opened in the third recess bottom surface 53A of the third recess 53, which is the deepest of the recess 50 that forms the discharge valve chamber 44. The oil returning passage 54 is, at the one end on the inner circumferential side thereof, opened in the first recess inner peripheral surface 51B having the circular shape of the first recess 51, which is the shallowest of the recess 50. This oil returning passage 54 extends outward and is, at the other end on the outer peripheral side thereof, opened in the suction chamber 61A. That is, the discharge valve chamber 44 and the suction chamber 61A communicate with each other through the oil returning passage 54.

In this case, a centrifugal force acts on the fluid discharged to the rotating discharge valve chamber 44 through the discharge port 45, so that oil is separated from the fluid by the centrifugal force. Then, the oil separated from the fluid is subjected to the centrifugal force in the discharge valve chamber 44 to flow outward. In addition, a large part of an opening of the recess 50 that forms the discharge valve chamber 44, that is, the entire first recess 51, the entire second recess 52, and a large part of the third recess 53 are covered by the cover portion 47. With this configuration, the cover portion 47 blocks most of the oil flowing out from the discharge valve chamber 44 toward the inner space 48A of the second boss 48 in the direction in which the driven axis R2 extends. In addition, in the discharge valve chamber 44, the oil may be stored in the second recess 52 that is separately provided from the third recess 53 in which the discharge valve mechanism 56 is accommodated and that is deeper than the first recess 51. Furthermore, the oil in the first recess 51 flows along the first recess inner peripheral surface 51B having the circular shape and is guided to the oil returning passage 54.

With these configurations, the oil in the discharge valve chamber 44 is easily introduced into the oil returning passage 54 that is opened in the first recess inner peripheral surface 51B. The oil introduced into the oil returning passage 54 is subjected to the centrifugal force to flow outward, and then, flows into the suction chamber 61A. The oil that has flowed into the suction chamber 61A contributes to oil lubrication and oil sealing at portions where lubrication and sealing properties are required.

Second Embodiment

As illustrated in FIG. 9 and FIG. 10, in a compressor of the second embodiment, the first recess 51 is excluded from the recess 50 that forms the discharge valve chamber 44. Furthermore, the one end on the inner peripheral side of the groove portion 541 of the oil returning passage 54 is opened in the second recess inner peripheral surface 52B of the second recess 52. The second recess inner peripheral surface 52B in which the oil returning passage 54 is opened is an example of the “inner peripheral surface of the discharge valve chamber” in the present invention.

In this compressor, the oil is separated from the fluid discharged into the rotating discharge valve chamber 44 by the centrifugal force, and the separated oil is subjected to the centrifugal force in the discharge valve chamber 44 to flow outward. In addition, a large part of an opening of the recess 50 that forms the discharge valve chamber 44, that is, the entire second recess 52 and a large part of the third recess 53 are covered by the cover portion 47. With this configuration, the cover portion 47 blocks most of the oil flowing out from the discharge valve chamber 44 toward the inner space 48A of the second boss 48 in the direction in which the driven axis R2 extends. In addition, in the discharge valve chamber 44, the oil may be stored in the second recess 52 that is separately provided from the third recess 53 in which the discharge valve mechanism 56 is accommodated.

With this configuration, the oil in the discharge valve chamber 44 is easily introduced into the oil returning passage 54 that is opened in the second recess inner peripheral surface 52B. The oil introduced into the oil returning passage 54 is subjected to the centrifugal force to flow outward, and then, flows into the suction chamber 61A. The oil that has flowed into the suction chamber 61A contributes to oil lubrication and oil sealing at portions where lubrication and sealing properties are required.

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.

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

For example, in the compressors of the first embodiment and the second embodiment, the driven scroll 40 is defined as the first scroll; however, the present invention is not limited thereto, and the driving scroll 30 may be defined as the first scroll.

In the compressors of the first embodiment and second embodiment, the suction port 35 is formed in the driving scroll 30 as the second scroll; however, the present invention is not limited thereto, and the suction port 35 may be formed in the driven scroll 40 as the first scroll.

In the compressors of the first embodiment and the second embodiment, the driving scroll protruding portion 31A is formed on the driving scroll end plate 31 of the driving scroll 30 as the second scroll, and the driven scroll spiral short portion 43A is formed in the driven scroll spiral body 43 of the driven scroll 40 as the first scroll; however, the driving scroll protruding portion 31A formed on the driving scroll end plate 31 and the driven scroll spiral short portion 43A formed in the driven scroll spiral body 43 may be omitted. In addition, the driven scroll protruding portion 41A formed on the driven scroll end plate 41 of the driven scroll 40 as the first scroll and the driving scroll spiral short portion 33A formed in the driving scroll spiral body 33 of the driving scroll 30 as the second scroll may be omitted.

In the first embodiment and the second embodiment, the groove portion 541 that is recessed in the front surface 411 of the driven scroll end plate 41 and the hole portion 542 that extends through the driven scroll end plate 41 in a thickness direction thereof form the oil returning passage 54; however, the present invention is not limited thereto, and a groove and a through hole that are formed in the gasket 40C or the cover portion 47 of the bearing cover body 40B may form an oil returning passage.

In the first embodiment and the second embodiment, the discharge valve chamber 44 and the suction chamber 61A communicate with each other through the oil returning passage 54; however, the present invention is not limited thereto, and the discharge valve chamber 44 and the compression chamber 55 may communicate with each other through the oil returning passage 54.

In the first embodiment and the second embodiment, the recess 50 for forming the discharge valve chamber 44 is formed in the driven scroll end plate 41 as the first end plate; however, the present invention is not limited thereto, and the recess 50 may be formed in the cover portion 47 of the bearing cover body 40B instead of in the driven scroll end plate 41 or the recess 50 may be formed in both the first end plate and the cover portion 47.

In the first embodiment and the second embodiment, the entire discharge valve mechanism 56 is disposed in the region corresponding to the driven scroll protruding portion 41A of the driven scroll end plate 41 as the first end plate; however, the present invention is not limited thereto. For example, the valve fixed proximal end portion 57B may be disposed in the region corresponding to the protruding portion of the first end plate, and the valve distal portion 57A may be disposed in a region corresponding to the non-protruding portion of the first end plate, or vice versa, the valve distal portion 57A may be disposed in the region corresponding to the protruding portion of the first end plate, and the valve fixed proximal end portion 57B may be disposed in the region corresponding to the non-protruding portion of the first end plate. Furthermore, in these cases, the recess 50 may be formed in both the first end plate and the cover portion 47.

In the compressors of the first embodiment and the second 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 slide on an inner peripheral surface of one free ring, a pin-and-pin mechanism in which outer peripheral surfaces of two pins slide on each other, a mechanism using an Oldham coupling, or the like.

In the compressors of the first embodiment and the second embodiment, the driving scroll 30 is integrated with the rotor 11 by fixing the driving scroll peripheral wall 32 to the inner peripheral surface of the rotor 11. 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.

Supplementary Note 1

A co-rotating scroll compressor comprising:

• • a housing having 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;
  • 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, wherein
  • the first scroll has a bearing cover body that is fixed to an end surface of the first end plate opposite to the compression chamber,
  • a discharge valve chamber that is a part of the discharge chamber is formed between the first end plate and the bearing cover body,
  • a discharge port through which the compression chamber and the discharge valve chamber communicate with each other is formed in the first end plate,
  • a discharge valve that opens and closes the discharge port is provided in the discharge valve chamber,
  • the bearing cover body has:
    • a cover portion that covers a part of the discharge valve chamber and a part of the discharge valve; and
    • a boss portion that has a cylindrical shape extending from an inner peripheral portion of the cover portion opposite to the compression chamber and has an inner space communicating with the discharge valve chamber, and
  • a bearing that rotatably supports the first scroll is provided on an outer peripheral surface of the boss portion.

Supplementary Note 2

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

• • the discharge valve is a discharge reed valve having a valve distal portion that opens and closes the discharge port and a valve fixed proximal end portion at which the discharge valve is fixed to the first end plate, and
  • the valve fixed proximal end portion is covered by the cover portion.

Supplementary Note 3

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

• • the valve distal portion is located close to a center of the boss portion compared to the valve fixed proximal end portion.

Supplementary Note 4

The co-rotating scroll compressor according to any one of supplementary notes 1 to 3, characterized in that

• • at least the first end plate of the first end plate and the second end plate has: a protruding portion that protrudes toward the first end plate facing the second end plate or the second end plate facing the first end plate, a non-protruding portion that is located outside the protruding portion; and an end plate stepped portion that connects the protruding portion and the non-protruding portion, and each of the first spiral body that protrudes from the first end plate facing the second end plate and the second spiral body that protrudes from the second end plate facing the first end plate has: a spiral main body portion; a spiral short portion that protrudes shorter than the spiral main body portion so that interference of the spiral short portion with the protruding portion is avoidable; and a spiral body stepped portion that connects the spiral main body portion and the spiral short portion, and
  • the discharge valve chamber is formed of a recess that is located in a region where the protruding portion is formed and is recessed in the end surface of the first end plate toward the compression chamber.

Supplementary Note 5

The co-rotating scroll compressor according to any one of supplementary notes 1 to 4, characterized in that

• • an oil returning passage that is opened in an inner peripheral surface of the discharge valve chamber and extends outward from the inner peripheral surface of the discharge valve chamber and through which the discharge valve chamber and the suction chamber or the compression chamber communicate with each other.

Industrial Applicability

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

Reference Signs List

• • 30 driving scroll (second scroll)
  • 31 driving scroll end plate (second end plate)
  • 31A driving scroll protruding portion (protruding portion)
  • 31B driving scroll non-protruding portion (non-protruding portion)
  • 31C driving scroll end plate stepped portion (end plate stepped portion)
  • 33 driving scroll spiral body (second spiral body)
  • 33A driving scroll spiral short portion (spiral short portion)
  • 33B driving scroll spiral main body portion (spiral main body portion)
  • 33C driving scroll spiral body stepped portion (spiral body stepped portion)
  • 40 driven scroll (first scroll)
  • 40B bearing cover body
  • 41 driven scroll end plate (first end plate)
  • 411 front surface (end surface)
  • 41A driven scroll protruding portion (protruding portion)
  • 41B driven scroll non-protruding portion (non-protruding portion)
  • 41C driven scroll end plate stepped portion (end plate stepped portion)
  • 43 driven scroll spiral body (first spiral body)
  • 43A driven scroll spiral short portion (spiral short portion)
  • 43B driven scroll spiral main body portion (spiral main body portion)
  • 43C driven scroll spiral body stepped portion (spiral body stepped portion)
  • 44 discharge valve chamber (discharge chamber)
  • 45 discharge port
  • 47 cover portion
  • 48 second boss (boss portion)
  • 48A inner space (discharge chamber)
  • 50 recess
  • 51B first recess inner peripheral surface (inner peripheral surface)
  • 52B second recess inner peripheral surface (inner peripheral surface)
  • 54 oil returning passage
  • 55 compression chamber
  • 57 discharge reed valve (discharge valve)
  • 57A valve distal portion
  • 57B valve fixed proximal end portion
  • 60 housing
  • 61A suction chamber
  • 65C discharge portion (discharge chamber)
  • 72 needle bearing (bearing)