Bidirectional rotary scroll-type compressor

Abstract

This compressor comprises: a housing (6); a drive mechanism (10); a drive scroll (30); a driven scroll (40); a driven mechanism (20); and a discharge chamber (14). The drive scroll (30) and the driven scroll (40) form a compression chamber (12). A refrigerant compressed in the compression chamber (12) is discharged to the discharge chamber (14). A protruding body (64) is provided in the housing (6). The protruding body (64) has a first diameter section (64a) and a second diameter section (64b). The drive scroll (30) has a cover body (37) that is rotatably supported by the first diameter section (64a) via a shaft support part (51). In the cover body (37), formed is a recirculation passage (37c) that communicates with the discharge chamber (14) and causes a lubricating oil (18) in the discharge chamber (14) to flow toward the protruding body (64). A connection passage (5) is formed in the second diameter section (64b). The recirculation passage (37c) and the connection passage (5) communicate on the outside of the shaft support part (51) in the radial direction of the cover body (37).

Description

Double-rotating scroll compressor

[0001] The present invention relates to a double-rotating scroll compressor.

[0002] Patent Document 1 discloses a conventional double-rotating scroll compressor (hereinafter simply referred to as a compressor). This compressor includes a housing, a drive mechanism, a drive scroll, a driven scroll, a driven mechanism, and a discharge chamber. The housing has a scroll chamber that houses the drive mechanism, the drive scroll, and the driven scroll. Refrigerant is drawn into the scroll chamber from outside the housing.

[0003] The drive mechanism has a stator and a rotor. The stator is fixed within the scroll chamber. The drive scroll has a cover body. The cover body has a cylindrical extension portion. The rotor is fixed to the outer peripheral surface of the extension portion. The driven scroll is eccentric with respect to the drive scroll and can be rotated by the drive scroll and driven mechanism around the driven axis. The drive scroll and driven scroll form a compression chamber that compresses the refrigerant by rotational driving and rotational following. A discharge chamber is formed in the driven scroll. The discharge chamber is in communication with the compression chamber.

[0004] In this compressor, a protrusion is provided on the housing. The protrusion protrudes into the scroll chamber in the drive axial direction toward the drive scroll and the driven scroll. The protrusion extends into the extension portion. A journal is provided between the inner peripheral surface of the extension portion and the outer peripheral surface of the protrusion. Thus, the drive scroll is rotatably supported by the protrusion via the journal.

[0005] A discharge passage is formed inside the protrusion and extends in the drive shaft direction. The discharge passage communicates with the discharge chamber on one side in the drive shaft direction and with the outside of the housing on the other side in the drive shaft direction.

[0006] In this compressor, as the rotor rotates in the drive mechanism, the drive scroll rotates integrally with the rotor about the drive axis. As a result, the driven scroll is rotated about the driven axis by the drive scroll and the driven mechanism. The volume of the compression chamber changes depending on the rotationally driven drive scroll and the rotationally driven driven scroll. As a result, in this compressor, refrigerant is drawn into the compression chamber and compressed. The refrigerant compressed in the compression chamber is discharged into the discharge chamber, and then flows from the discharge chamber through a discharge passage and is discharged to the outside of the housing, i.e., the outside of the compressor.

[0007] Japanese Unexamined Patent Publication No. 2-227575

[0008] The refrigerant drawn into the compression chamber contains lubricating oil, which is discharged from the compression chamber to the discharge chamber together with the compressed refrigerant. Therefore, it is conceivable to use such lubricating oil to lubricate the drive scroll, the driven scroll, the journal, etc.

[0009] However, in the conventional compressor, most of the lubricating oil discharged into the discharge chamber flows through the discharge passage together with the refrigerant and is discharged to the outside of the compressor. As a result, in this compressor, the lubricating oil discharged into the discharge chamber cannot be used sufficiently to lubricate the drive scroll, the driven scroll, the journal support, etc. Therefore, there is a concern that the durability of such a compressor will be reduced due to insufficient lubrication of the drive scroll, the driven scroll, the journal support, etc.

[0010] The present invention has been made in view of the above-mentioned conventional circumstances, and an object to be achieved is to provide a double-rotation scroll compressor having excellent durability.

[0011] The double-rotating scroll compressor of the present invention comprises a housing, a drive mechanism, a driving scroll, a driven scroll, a driven mechanism, and a discharge chamber, wherein the housing has a scroll chamber in which the driving scroll and the driven scroll are accommodated, the driving scroll is rotationally driven about a drive axis by the drive mechanism, and the driven scroll is rotationally driven by the driving scroll and the driven mechanism about a driven axis while being eccentric with respect to the driving scroll, the driving scroll and the driven scroll form compression chambers that compress a refrigerant by the rotational driving and the rotational driven, and the refrigerant compressed in the compression chambers is discharged into the discharge chamber, wherein the housing is provided with a protrusion that protrudes into the scroll chamber in the drive axis direction toward the driving scroll and the driven scroll, the protrusion has a first diameter portion and a second diameter portion having a diameter larger than the first diameter portion, and the driving scroll has a cover body rotatably supported on the first diameter portion via a journal portion, The cover body is formed with a return passage that communicates with the discharge chamber and allows the lubricating oil in the discharge chamber to flow toward the protrusion; a lubricating oil passage is formed within the housing, located radially inside the drive mechanism and through which the lubricating oil can flow; a connecting passage is formed in the second diameter portion, which communicates the outside of the second diameter portion with the lubricating oil passage and through which the lubricating oil can flow toward the lubricating oil passage; and the return passage and the connecting passage are connected radially outside the cover body relative to the support portion.

[0012] In the double-rotating scroll compressor of the present invention, the drive scroll has a cover body, and the cover body is rotatably supported by the first diameter portion of the protruding body via a journal portion. In this compressor, refrigerant compressed in the compression chamber is discharged to the discharge chamber. Here, the refrigerant discharged to the discharge chamber contains lubricating oil.

[0013] Furthermore, a lubricating oil passage is formed within the housing radially inward of the drive mechanism. A connecting passage is formed in the second diameter portion of the protrusion, and the connecting passage connects the outside of the second diameter portion to the lubricating oil passage. In this compressor, the return passage and the connecting passage communicate with each other, allowing lubricating oil from the discharge chamber to circulate through the return passage and the connecting passage. This prevents lubricating oil from the discharge chamber from being discharged from the discharge chamber to the outside of the compressor along with the refrigerant.

[0014] In this compressor, the lubricating oil flowing from the return passage to the connecting passage can lubricate the bearing part, and the lubricating oil that reaches the lubricating oil passage can be used to lubricate the driving scroll, driven scroll, etc.

[0015] In this compressor, a gap exists between the journal support and the first diameter portion or between the journal support and the cover body, allowing the journal support to slide when the drive scroll rotates. Therefore, if the return passage and the connecting passage are configured to communicate with each other radially inward of the cover body relative to the journal support, the lubricating oil in the return passage will easily flow into the scroll chamber through the gap as the drive scroll rotates. This reduces the amount of lubricating oil that reaches the lubricating oil passage, raising concerns that the lubricating oil may not be able to sufficiently lubricate the drive scroll, driven scroll, etc.

[0016] In this compressor, the return passage and the connecting passage communicate with each other radially outward of the cover body relative to the support portion. This prevents excessive leakage of lubricating oil from the return passage into the scroll chamber through the gap. As a result, the compressor allows sufficient lubricating oil to flow through the lubricating oil passage, which can be used effectively to lubricate the drive scroll, driven scroll, etc.

[0017] Therefore, the double-rotating scroll compressor of the present invention has excellent durability.

[0018] In addition, in this compressor, since the second diameter portion of the protrusion is larger than the first diameter portion, the rigidity of the protrusion can be ensured by the second diameter portion, and the formation of a lubricating oil passage for the second diameter portion can be facilitated. Furthermore, since the first diameter portion is smaller than the second diameter portion, the compressor can prevent the bearing portion from becoming large.

[0019] In the compressor of the present invention, the return passage may have a first passage communicating with the discharge chamber and a second passage communicating with the first passage and the connecting passage. The second diameter portion may have a first end face facing the cover body in the drive shaft direction and having an opening to the connecting passage. The cover body may have a second end face facing the first end face in the drive shaft direction and having an opening to the second passage. An outer sealing member is preferably provided between the first end face and the second end face, extending annularly and positioned radially outward of the connecting passage and the second passage, to seal the gap between the first end face and the second end face.

[0020] In this compressor, because the drive scroll is driven to rotate, a gap also exists in the drive shaft direction between the first end face of the second diameter portion and the second end face of the cover body. In this regard, in this compressor, the gap between the first end face and the second end face is sealed by the outer sealing member, so that lubricating oil flowing from the second passage toward the connecting passage can be effectively prevented from leaking into the scroll chamber through the gap between the first end face and the second end face.

[0021] In this case, an inner circumferential sealing member is preferably provided between the first end face and the second end face, extending annularly and positioned radially inward of the second passage and the connecting passage, and sealing the gap between the first end face and the second end face. This allows the inner circumferential sealing member to also seal the gap between the first end face and the second end face, making it possible to more effectively prevent lubricating oil flowing from the second passage toward the connecting passage from leaking into the scroll chamber through the gap between the first end face and the second end face.

[0022] In the compressor of the present invention, the return passage may have a first passage communicating with the discharge chamber and a second passage communicating with the first passage and the connecting passage. Furthermore, the second diameter portion may have a first end face facing the cover body in the drive shaft direction and having an opening for the connecting passage. Furthermore, the cover body may have a second end face facing the first end face in the drive shaft direction and having an opening for the second passage. Preferably, an annular passage extending annularly and communicating with the connecting passage and the second passage is formed between the first end face and the second end face.

[0023] In this case, even if the relative positions of the connecting passage and the second passage change as the drive scroll rotates, the connecting passage and the second passage can be preferably communicated with each other through the annular passage, and therefore, in this compressor, the lubricating oil in the discharge chamber can be preferably circulated to the lubricating oil passage.

[0024] The lubricating oil passage is preferably capable of storing lubricating oil therein, so that the lubricating oil in the lubricating oil passage can be more easily utilized for lubricating the driving scroll, the driven scroll, and the like.

[0025] The double-rotating scroll compressor of the present invention is excellent in durability.

[0026] Fig. 1 is a cross-sectional view of a compressor according to an embodiment of the present invention, and Fig. 2 is an enlarged cross-sectional view of a main part of the compressor according to the embodiment, showing a return passage, a connecting passage, a lubricating oil passage, etc.

[0027] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A double rotary scroll compressor according to an embodiment of the present invention is mounted in a vehicle (not shown) and forms an air conditioning system for the vehicle.

[0028] 1, the compressor of the first embodiment includes a housing 6, an electric motor 10, a driving scroll 30, a driven scroll 40, a driven mechanism 20, and a discharge chamber 14. The electric motor 10 is an example of the "drive mechanism" of the present invention.

[0029] In this embodiment, the front-rear direction and the up-down direction of the compressor are defined by solid arrows shown in Fig. 1. The front-rear direction and the up-down direction of the compressor are defined in Fig. 2 in accordance with Fig. 1. The front-rear direction and the up-down direction are perpendicular to each other. Note that these front-rear directions are merely examples for the sake of convenience, and the compressor's position can be changed as appropriate depending on the vehicle in which it is installed.

[0030] 1, the housing 6 is made up of a housing body 60 and a housing cover 62. The housing body 60 and the housing cover 62 are made of an aluminum alloy.

[0031] The housing body 60 is a cylindrical member having an outer peripheral wall 60a and a rear wall 60b. The outer peripheral wall 60a is cylindrical and has a drive axis O1 as its center. The drive axis O1 is parallel to the front-rear direction.

[0032] An intake communication port 68 is formed in the outer peripheral wall 60a. The intake communication port 68 extends in the radial direction of the housing body 60. The intake communication port 68 is connected to an evaporator (not shown) through a pipe (not shown).

[0033] The rear wall 60b is located at the rear end of the housing main body 60. The rear wall 60b extends in a generally circular, flat plate shape perpendicular to the drive axis O1. The outer peripheral edge of the rear wall 60b is connected to the rear end of the outer peripheral wall 60a. The rear wall 60b also has a mounting recess 60c formed therein. The mounting recess 60c is recessed from the front to the rear on the inner surface of the rear wall 60b.

[0034] A protrusion 64 is provided inside the housing 6. More specifically, the protrusion 64 is provided inside the housing main body 60. The protrusion 64 is made of steel. The protrusion 64 has a first diameter portion 64a and a second diameter portion 64b. The first diameter portion 64a and the second diameter portion 64b are integrally formed. The protrusion 64 may also be made of an aluminum alloy.

[0035] The first diameter portion 64a constitutes the front portion of the protrusion 64. The first diameter portion 64a is formed in a generally cylindrical shape extending in the drive shaft direction. The first diameter portion 64a is formed to have a smaller diameter than an insertion hole 37d, which will be described later. A pin hole 4 is formed in the first diameter portion 64a. As shown in FIG. 2 , the pin hole 4 is recessed from a front end surface 81 of the first diameter portion 64a toward the rear within the first diameter portion 64a. As a result, the pin hole 4 does not penetrate the first diameter portion 64a in the drive shaft O1 direction.

[0036] Additionally, a first plain bearing 51 is provided on the outer peripheral surface of the first diameter portion 64a. The first plain bearing 51 is an example of the "bearing portion" in the present invention.

[0037] The second diameter portion 64b is located rearward of the first diameter portion 64a and constitutes the rear portion of the protrusion 64. The second diameter portion 64b is formed to have a larger diameter than the first diameter portion 64a. The second diameter portion 64b is made up of a main body portion 641 and a flange portion 642. The main body portion 641 constitutes the front portion of the second diameter portion 64b, and the flange portion 642 constitutes the rear portion of the second diameter portion 64b.

[0038] The main body portion 641 is coaxial with the first diameter portion 64a and extends in the direction of the drive axis O1. The main body portion 641 has a connecting end surface 82 at the first diameter portion 64a. The connecting end surface 82 is an example of the "second end surface" of the present invention. The connecting end surface 82 is located at the front end of the second diameter portion 64b and faces forward. The connecting end surface 82 extends radially of the protrusion 64 and connects to the first diameter portion 64a.

[0039] The flange portion 642 is formed to have a larger diameter than the main body portion 641, and extends outward beyond the main body portion 641 in the radial direction of the second diameter portion 64b.

[0040] The second diameter portion 64b is formed with an oil reservoir 3, a connecting passage 5, and a discharge passage 8. The oil reservoir 3 is an example of a "lubricating oil passage" in the present invention. As described above, the protrusion 64 is provided inside the housing 6. Therefore, the oil reservoir 3 is formed in the second diameter portion 64b, and thus the oil reservoir 3 is formed inside the housing 6. Inside the housing 6, the oil reservoir 3 is located radially inward of the electric motor 10.

[0041] The oil reservoir 3 opens at the rear end surface of the flange portion 642, i.e., at the rear end of the second diameter portion 64b. The oil reservoir 3 is recessed from the rear end surface of the flange portion 642 toward the inside of the main body portion 641 in the direction of the drive axis O1. The oil reservoir 3 has a diameter larger than the pin hole 4 and the connecting passage 5. The oil reservoir 3 does not communicate with the pin hole 4.

[0042] The connecting passage 5 is formed in the main body portion 641 and penetrates the main body portion 641 in the direction of the drive axis O1. As a result, the rear end of the connecting passage 5 communicates with the oil reservoir chamber 3. The front end of the connecting passage 5 opens to the connecting end face 82. As a result, the connecting passage 5 communicates the oil reservoir chamber 3 with the outside of the protruding body 64 at a position radially outward of the protruding body 64 relative to the first diameter portion 64a.

[0043] As shown in FIG. 1 , the discharge passage 8 is formed in the main body portion 641 at a position rearward of an extension portion 37b of the cover body 37, which will be described later, in the direction of the drive axis O1. The discharge passage 8 is also formed at a position on the lower side of the main body portion 641 when the protrusion 64 is fixed to the rear wall 60b. As a result, the discharge passage 8 is located rearward and lower than the connecting passage 5. The discharge passage 8 penetrates the main body portion 641 in the radial direction of the protrusion 64. As a result, the discharge passage 8 connects the oil reservoir chamber 3 downward to the outside of the protrusion 64. The discharge passage 8 may also be formed in the flange portion 642.

[0044] The protrusion 64 is fixed to the rear wall 60b by fitting the flange portion 642 into the mounting recess 60c. Thus, the rear end of the oil reservoir 3 of the protrusion 64 is closed by the rear wall 60b.

[0045] The housing cover 62 is disposed in front of the housing main body 60. The housing cover 62 is generally disk-shaped and centered on the drive axis O1. The housing cover 62 has a front surface 62a facing forward and a rear surface 62b facing rearward and located on the opposite side of the front surface 62a.

[0046] The housing cover 62 also has a support portion 66 and a discharge communication port 69. The support portion 66 is integrally formed approximately at the center of the rear surface 62b and protrudes rearward from the rear surface 62b. The support portion 66 is formed in a cylindrical shape centered on the drive axis O1, and is provided with a ball bearing 52 and a shaft seal member 63 inside. The ball bearing 52 is an example of the "bearing" in the present invention. Note that a sliding bearing may be provided inside the support portion 66 instead of the ball bearing 52.

[0047] The shaft seal member 63 is disposed inside the support portion 66 and forward of the ball bearing 52. The shaft seal member 63 is formed in an annular shape.

[0048] The discharge communication port 69 penetrates the housing cover 62 in the direction of the drive axis O1 and communicates with the inside of the support portion 66. The discharge communication port 69 is also connected to a condenser (not shown) through piping (not shown).

[0049] In the housing 6, the rear surface 62b of the housing cover 62 abuts against the front end of the outer peripheral wall 60a of the housing main body 60. In this state, the housing cover 62 is fixed to the housing main body 60 with a plurality of bolts (not shown) from the housing cover 62 side. In this way, in the housing 6, the housing main body 60 and the housing cover 62 are integrated.

[0050] In the housing 6, the front of the housing body 60 is closed by the housing cover 62, thereby forming a scroll chamber 65 inside the housing body 60. The scroll chamber 65 communicates with an intake communication port 68. As a result, refrigerant is drawn into the scroll chamber 65 from outside the housing 6 through the intake communication port 68.

[0051] Furthermore, the above-mentioned protrusion 64 is fixed to the rear wall 60b, and thereby protrudes from the rear wall 60b into the scroll chamber 65 in the direction of the drive axis O1. More specifically, the protrusion 64 protrudes forward from the rear wall 60b toward the driving scroll 30 and the driven scroll 40. The second diameter portion 64b of the protrusion 64 separates the scroll chamber 65 from the oil storage chamber 3. The discharge passage 8 connects the oil storage chamber 3 to the scroll chamber 65.

[0052] The electric motor 10 is housed in the scroll chamber 65. As a result, the scroll chamber 65 also serves as a motor chamber that houses the electric motor 10.

[0053] The electric motor 10 is composed of a stator 17 and a rotor 11. The stator 17 is cylindrical and has a drive shaft O1 as its center, and has windings 17a. The stator 17 is fixed to the housing main body 60 and, by extension, the housing 6, by fitting into the inner peripheral surface of the outer peripheral wall 60a.

[0054] The rotor 11 is cylindrical around the drive axis O1 and is disposed inside the stator 17. Although not shown in detail, the rotor 11 has a plurality of permanent magnets corresponding to the stator 17 and laminated steel plates that secure the permanent magnets.

[0055] The driving scroll 30 is made of a metal such as an aluminum alloy and is housed in a scroll chamber 65. The driving scroll 30 includes a driving end plate 31, a driving scroll 33, a driving peripheral wall 35, a cover body 37, and a case 39.

[0056] The drive end plate 31 extends in a generally disk-like shape, perpendicular to the drive axis O1 and the driven axis O2. The driven axis O2 extends parallel to the drive axis O1 while being eccentric with respect to the drive axis O1. In other words, the driven axis O2 is also parallel to the front-to-rear direction. The drive end plate 31 has a first front surface 311 facing forward and a first rear surface 312 located opposite the first front surface 311 and facing rearward.

[0057] A discharge port 32 is formed in the drive end plate 31. The discharge port 32 penetrates the drive end plate 31 in the direction of the drive axis O1. A discharge reed valve 57 and a retainer 58 are fixed to the first front surface 311 of the drive end plate 31 with fixing bolts 59. This allows the discharge reed valve 57 to open and close the discharge port 32. The retainer 58 can adjust the opening degree of the discharge reed valve 57.

[0058] The drive scroll 33 is integral with the drive end plate 31 and protrudes rearward from the first rear surface 312, i.e., parallel to the drive axis O1 and the driven axis O2, toward the driven scroll 40. Although not shown in detail, the drive scroll 33 has a spiral center located on the central side of the drive end plate 31 and protrudes outward from the spiral center in a spiral shape.

[0059] The drive circumferential wall 35 is formed in a cylindrical shape centered on the drive axis O1 and extending parallel to the drive axis O1 and the driven axis O2. The front end of the drive circumferential wall 35 is integral with the outer periphery of the drive end plate 31. As a result, the drive circumferential wall 35 surrounds the drive scroll 33 from the outside and protrudes cylindrically rearward from the first rear surface 312. Although not shown, the outer periphery of the drive scroll 33 is connected to the inner periphery of the drive circumferential wall 35.

[0060] A first supply passage 35a is formed in the drive end plate 31 and the drive peripheral wall 35. The first supply passage 35a penetrates the drive end plate 31 and the drive peripheral wall 35 in the direction of the drive axis O1. As a result, the front end of the first supply passage 35a opens at the first front surface 311 of the drive end plate 31. The rear end of the first supply passage 35a opens at the rear end of the drive peripheral wall 35.

[0061] The cover body 37 comprises a cover main body portion 37a and an extension portion 37b. The cover main body portion 37a extends in a generally disk-like shape, perpendicular to the drive axis O1 and the driven axis O2. The cover main body portion 37a is formed to have generally the same diameter as the drive end plate 31 and the drive peripheral wall 35. The cover main body portion 37a has a second front surface 371 facing forward and a second rear surface 372 facing rearward, located on the opposite side of the second front surface 371. The second rear surface 372 is an example of the "first end surface" in the present invention.

[0062] The cover body 37a is formed with a return passage 37c, an insertion hole 37d, a suction passage 37e, a first bolt hole 37f, and an annular passage 37g.

[0063] The return passage 37c is composed of a recess 373, a first passage 374, and a second passage 375. As shown in FIG. 2 , the recess 373 is located approximately in the center of the second front surface 371 and is recessed rearward from the second front surface 371. One end of the first passage 374 opens to the second front surface 371. The first passage 374 extends inside the cover main body 37a and has the other end opening into the recess 373.

[0064] The second passage 375 is located at a position radially outward of the cover body 37 with respect to the insertion hole 37d and the first plain bearing 51. The second passage 375 extends inside the cover main body 37a in the direction of the drive axis O1. As a result, the front end of the second passage 375 communicates with the recess 373. The second passage 375 also communicates with the first passage 374 through the recess 373. The rear end of the second passage 375 also communicates with the annular passage 37g.

[0065] The insertion hole 37d penetrates the cover main body 37a in the direction of the drive axis O1. The insertion hole 37d is formed in a cylindrical shape centered on the drive axis O1, and its front end communicates with the recess 373, i.e., the return passage 37c. The insertion hole 37d is formed with approximately the same diameter as the outer diameter of the first plain bearing 51.

[0066] The suction passage 37e is disposed radially outward of the cover body 37 relative to the recess 373 and the second passage 375 and at a location different from the first passage 374. As a result, the suction passage 37e is not in communication with the return passage 37c. The suction passage 37e penetrates the cover main body 37a in the direction of the drive axis O1, and its front end opens to the second front surface 371 at a location different from the first passage 374. Meanwhile, the rear end of the suction passage 37e opens to the second rear surface 372 at a location radially outward of the cover body 37 relative to the extension portion 37b. Note that the rear end of the suction passage 37e may also open to the second rear surface 372 at a location radially inward of the cover body 37 relative to the extension portion 37b.

[0067] The first bolt holes 37f are disposed radially outward of the cover body 37 relative to the suction passages 37e. The first bolt holes 37f penetrate the cover main body 37a in the direction of the drive axis O1. A plurality of first bolt holes 37f are formed in the cover main body 37a.

[0068] The annular passage 37g is located at a position radially outward of the cover body 37 relative to the insertion hole 37d and the first plain bearing 51, and radially inward of the cover body 37 relative to the extension portion 37b. The annular passage 37g is recessed forward from the second rear surface 372 and surrounds the drive axis O1. As a result, the annular passage 37g is formed in an annular shape that is centered on the drive axis O1 and has a diameter larger than the insertion hole 37d and the first plain bearing 51. As described above, the rear end of the second passage 375 is in communication with the annular passage 37g. As a result, the annular passage 37g functions as part of the return passage 37c.

[0069] In addition, in the cover main body portion 37a, an outer peripheral sealing member 71 and an inner peripheral sealing member 72 are provided on the second rear surface 372. More specifically, the outer peripheral sealing member 71 and the inner peripheral sealing member 72 are provided on the second rear surface 372 at a location that is radially inward of the cover body 37 relative to the extending portion 37b.

[0070] The outer sealing member 71 and the inner sealing member 72 are both made of PTFE (polytetrafluoroethylene) and formed in an annular shape. The outer sealing member 71 has a larger diameter than the inner sealing member 72. The outer sealing member 71 is disposed radially outward of the cover body 37 relative to the second passage 375, the annular passage 37g, and the connecting passage 5. On the other hand, the inner sealing member 72 is disposed radially inward of the cover body 37 relative to the second passage 375, the annular passage 37g, and the connecting passage 5. Although not shown in detail, in this compressor, two accommodation grooves capable of accommodating the outer sealing member 71 and the inner sealing member 72, respectively, are formed in the second rear surface 372. The outer sealing member 71 and the inner sealing member 72 are accommodated in the respective accommodation grooves, thereby providing the outer sealing member 71 and the inner sealing member 72 at the above-mentioned locations on the second rear surface 372.

[0071] Additionally, a plurality of rings 22 are attached to the cover main body 37a between the recess 373 and the suction passage 37e. Although not shown in detail, the rings 22 are disposed at equal intervals around the circumferential direction of the recess 373 while facing forward, and surround the recess 373 from the outside. In this embodiment, there are six rings 22. Also, one each of the rings 22 and the first bolt hole 37f is shown in Figures 1 and 2.

[0072] The extension portion 37b is formed integrally with the cover main body portion 37a and extends cylindrically rearward in the direction of the drive axis O1 from the second rear surface 372. The extension portion 37b has an inner diameter larger than that of the second diameter portion 64b of the protrusion 64, more specifically, the main body portion 641 of the second diameter portion 64b. On the other hand, the extension portion 37b has an outer diameter smaller than that of the rotor 11.

[0073] The cover body 37 has the second front surface 371 of the cover main body portion 37a abutting against the rear end of the drive peripheral wall 35. In this state, the first bolts 34a are inserted into the first bolt holes 37f and screwed into the drive peripheral wall 35. In this manner, the cover body 37 is fixed to the drive peripheral wall 35 of the driving scroll 30. As a result, one end of the first passage 374 is aligned with the rear end of the first supply passage 35a. This allows the first passage 374, and therefore the return passage 37c, to communicate with the first supply passage 35a.

[0074] 1, the case 39 is a cylindrical member with a bottom and an outer peripheral wall 39a and a front wall 39b. The outer peripheral wall 39a is cylindrical and has its center on the drive axis O1. The outer diameter of the outer peripheral wall 39a is larger than that of the ball bearing 52 and is approximately the same diameter as that of the drive end plate 31.

[0075] A second supply passage 39c is formed in the outer peripheral wall 39a. One end of the second supply passage 39c opens to the inner peripheral surface of the outer peripheral wall 39a. The second supply passage 39c extends inside the outer peripheral wall 39a and the other end opens to the rear end of the outer peripheral wall 39a.

[0076] The front wall 39b is located at the front end of the case 39. The front wall 39b extends in a generally disk-like shape, perpendicular to the drive axis O1 and the driven axis O2. The outer peripheral edge of the front wall 39b is connected to the front end of the outer peripheral wall 39a.

[0077] A boss 39d is formed on the front wall 39b. The boss 39d is an example of the "supported member" of the present invention. The boss 39d is integrally formed at the center of the front wall 39b and protrudes forward from the front wall 39b in the direction of the drive axis O1. The boss 39d has approximately the same diameter as the inner diameter of the ball bearing 52 and the inner diameter of the shaft seal member 63. A discharge passage 390 is formed in the boss 39d. The discharge passage 390 penetrates the boss 39d in the direction of the drive axis O1.

[0078] Furthermore, second bolt holes 39e are formed in the outer peripheral wall 39a and the front wall 39b. The second bolt holes 39e penetrate the outer peripheral wall 39a and the front wall 39b in the direction of the drive axis O1. The second bolt holes 39e do not communicate with the second supply passage 39c. A plurality of second bolt holes 39e are formed in the outer peripheral wall 39a and the front wall 39b. FIG. 1 illustrates one of the plurality of second bolt holes 39e.

[0079] The rear end of the outer peripheral wall 39a of the case 39 abuts against the first front surface 311 of the driving end plate 31. In this state, the second bolts 34b are inserted into the second bolt holes 39e, respectively, and the second bolts 34b are screwed into the driving end plate 31. In this way, the case 39 of the driving scroll 30 is fixed to the driving end plate 31.

[0080] By fixing the case 39 to the drive end plate 31 in this manner, a discharge chamber 14 is formed inside the outer peripheral wall 39a, between the front wall 39b of the case 39 and the drive end plate 31. The discharge chamber 14 is formed with a diameter larger than that of the ball bearing 52. The discharge chamber 14 is also in communication with the discharge port 32 and the discharge passage 390. Furthermore, one end of the second supply passage 39c is in communication with the discharge chamber 14.

[0081] Furthermore, by fixing the case 39 to the drive end plate 31, the other end of the second supply passage 39c is aligned with the front end of the first supply passage 35a. This allows the second supply passage 39c to communicate with the first supply passage 35a. As a result, in the drive scroll 30, the first passage 374, and therefore the return passage 37c, communicate with the discharge chamber 14 via the first supply passage 35a and the second supply passage 39c.

[0082] The driven scroll 40 is also made of an aluminum alloy. The driven scroll 40 has a driven end plate 41 and a driven scroll 43.

[0083] The driven end plate 41 has a generally disk-like shape and extends perpendicular to the drive axis O1 and the driven axis O2. The driven end plate 41 has a third front surface 411 facing forward and a third rear surface 412 located on the opposite side of the third front surface 411 and facing rearward.

[0084] An accommodating recess 15 is formed in the driven end plate 41. The accommodating recess 15 is located in the center of the driven end plate 41. The accommodating recess 15 is recessed in a cylindrical shape centered on the driven axis O2 and extends forward from the third rear surface 412 of the driven end plate 41. As a result, the accommodating recess 15 faces the rear of the driven end plate 41, and ultimately faces the first diameter portion 64a of the protrusion 64.

[0085] A driven shaft portion 16 is provided in the accommodation recess 15. The driven shaft portion 16 has a bushing 53 and a driven pin 55. The bushing 53 is accommodated in the accommodation recess 15 via the second plain bearing 13. The driven pin 55 is inserted through the bushing 53. More specifically, the driven pin 55 is inserted through the bushing 53 at a position eccentric to the center of the bushing 53, i.e., the driven axis O2. The driven pin 55 protrudes rearward from the bushing 53 and, therefore, from the driven end plate 41.

[0086] Furthermore, a rotation prevention pin 21 is fixed to the driven end plate 41 at a position facing the ring 22. The rotation prevention pin 21 protrudes rearward from the third rear surface 412. Six rotation prevention pins 21 are fixed to the driven end plate 41, the same number as the number of rings 22. Also, one of the rotation prevention pins 21 is shown in FIG. 1.

[0087] These rotation-preventing pins 21 and rings 22 constitute the driven mechanism 20. The number of rotation-preventing pins 21 and rings 22 can be appropriately designed as long as there are three or more of each.

[0088] The driven spiral body 43 is integral with the driven end plate 41 and extends forward from the third front surface 411 of the driven end plate 41 in parallel with the drive axis O1 and the driven axis O2. The driven spiral body 43 has a spiral center on the center side of the driven end plate 41 and extends spirally outward from the spiral center.

[0089] In this compressor, the driven scroll 40 is housed within the driving scroll 30, more specifically, in a location in the driving scroll 30 between the driving scroll 33 and the driving peripheral wall 35 and the cover body 37. The driving scroll 30 and the driven scroll 40 are arranged such that the driving scroll 33 and the driven scroll 43 are meshed with each other. As a result, the driving scroll 33 and the driven scroll 43 face each other to form a compression chamber 12.

[0090] Furthermore, an intake section 30a is formed between the driving peripheral wall 35 and the driven scroll 40. That is, the driving scroll 33 and the driven scroll 43 are located within the intake section 30a. The intake section 30a is separated from the scroll chamber 65 by the driving end plate 31, the driving peripheral wall 35, and the cover body 37, and is also separated from the discharge chamber 14 by the driving end plate 31. The intake section 30a also communicates with an intake passage 37e.

[0091] Furthermore, by accommodating the driven scroll 40 within the driving scroll 30, each of the rotation-preventing pins 21 enters each of the rings 22. In this manner, the driving scroll 30 and the driven scroll 40 are assembled in the front-to-rear direction, and the driving scroll 30 and the driven scroll 40 form a scroll compression section 100. Strictly speaking, after the driving scroll 33 and the driven scroll 43 are engaged with each other and the rotation-preventing pins 21 enter each of the rings 22, the cover body 37 of the driving scroll 30 is fixed to the driving peripheral wall 35.

[0092] Furthermore, by assembling the driving scroll 30 and the driven scroll 40, the accommodation recess 15 of the driven end plate 41 and the bushing 53 face the recess 373, that is, the return passage 37c.

[0093] The driving scroll 30 is disposed in the scroll chamber 65 forward of the electric motor 10. In addition, the driving scroll 30 fixes the rotor 11 to the extending portion 37b of the cover body 37. More specifically, the extending portion 37b is inserted into the rotor 11, and the outer peripheral surface of the extending portion 37b is fixed to the rotor 11. In this way, the driving scroll 30 is fixed to the rotor 11 via the extending portion 37b.

[0094] 2, in the driving scroll 30, the first diameter portion 64a of the protrusion 64 and the main body portion 641 of the second diameter portion 64b are inserted into the extension portion 37b. Furthermore, in the driving scroll 30, the first plain bearing 51 is inserted into the insertion hole 37d of the cover body 37. As a result, the cover body 37 is rotatably supported on the first diameter portion 64a via the first plain bearing 51. Furthermore, by inserting the first plain bearing 51 into the insertion hole 37d, the front portion of the first plain bearing 51 faces the recess 373. Furthermore, the pin hole 4 faces the bushing 53 in the direction of the drive axis O1.

[0095] Furthermore, because the cover body 37 is rotatably supported on the first diameter portion 64a via the first plain bearing 51 in this manner, the second rear surface 372 of the cover main body portion 37a and the connecting end surface 82 of the protrusion 64 face each other in the direction of the drive axis O1. Thus, the annular passage 37g, the outer peripheral sealing member 71, and the inner peripheral sealing member 72 are located between the second rear surface 372 and the connecting end surface 82.

[0096] In the protrusion 64, the connecting passage 5 faces the annular passage 37g and communicates with the annular passage 37g. In other words, the connecting passage 5 is formed on the connecting end surface 82 at a position that allows communication with the annular passage 37g. This allows communication between the second passage 375 of the return passage 37c and the connecting passage 5 through the annular passage 37g.

[0097] In this way, the second passage 375 and the connecting passage 5 communicate with each other through the annular passage 37g, and thus the oil reservoir chamber 3 and the return passage 37c communicate with each other.

[0098] Furthermore, the connection end surface 82 abuts against the outer-periphery sealing member 71 and the inner-periphery sealing member 72. As a result, the outer-periphery sealing member 71 seals the gap between the second rear surface 372 and the connection end surface 82, and further outward from the annular passage 37g and the connection passage 5 in the radial direction of the cover body 37. The inner-periphery sealing member 72 seals the gap between the second rear surface 372 and the connection end surface 82, and further inward from the annular passage 37g in the radial direction of the cover body 37. More specifically, the inner-periphery sealing member 72 seals the gap between the second rear surface 372 and the connection end surface 82, further inward from the annular passage 37g and the connection passage 5 in the radial direction of the cover body 37.

[0099] 1 , in the driving scroll 30, the boss 39d of the case 39 is inserted into the ball bearing 52 and the shaft seal member 63. As a result, the case 39 is rotatably supported by the support portion 66 via the ball bearing 52. In this way, the driving scroll 30 is disposed in the scroll chamber 65 and is supported by the housing 6 by both the protrusion 64 and the support portion 66 so as to be rotatable about the drive axis O1.

[0100] Furthermore, since the case 39 is supported by the support portion 66, the discharge passage 390 faces the discharge communication port 69 from the rear. This allows the discharge chamber 14 to communicate with the discharge communication port 69 through the discharge passage 390. Here, in the driving scroll 30, the shaft seal member 63 seals the space between the discharge passage 390 and the scroll chamber 65.

[0101] On the other hand, in the driven scroll 40, the driven pin 55 is inserted into the pin hole 4. As a result, the driven scroll 40 is disposed in the scroll chamber 65 and is supported rotatably around the driven axis O2 with respect to the first diameter portion 64a of the protruding body 64.

[0102] In the compressor configured as described above, as indicated by the dashed arrows in Figures 1 and 2, low-temperature, low-pressure refrigerant that has passed through the evaporator is drawn into the scroll chamber 65 through the suction port 68. When the electric motor 10 is operated and the rotor 11 rotates, the rotation of the rotor 11 is transmitted to the driving scroll 30, causing the driving scroll 30 to rotate about the drive axis O1 within the scroll chamber 65. In other words, the driving scroll 30 and the rotor 11 rotate integrally. At this time, in the driven mechanism 20, each rotation-preventing pin 21 slides against the inner circumferential surface of each ring 22, causing the rings 22 to rotate relatively about the center of the rotation-preventing pin 21. In this way, the driven mechanism 20 transmits the torque of the driving scroll 30 to the driven scroll 40.

[0103] As a result, the driven scroll 40 is rotated around the driven axis O2 by the driving scroll 30 and the driven mechanism 20. At this time, the driven mechanism 20 restricts the rotation of the driven scroll 40. As a result, the driven scroll 40 revolves around the driven axis O2 relative to the driving scroll 30. Then, as the driving scroll 33 and the driven scroll 43 each rotate within the suction section 30a, the driving scroll 33 and the driven scroll 43 change the volume of the compression chamber 12.

[0104] The refrigerant drawn into the scroll chamber 65 flows toward the suction passage 37e. The refrigerant drawn into the scroll chamber 65 contains lubricating oil 18. The refrigerant that reaches the suction passage 37e is then drawn from the suction passage 37e through the suction section 30a into the compression chamber 12. The compression chamber 12 compresses the refrigerant by reducing its volume while trapping the refrigerant therein due to the rotational driving of the drive scroll 30 and the rotational driven movement of the driven scroll 40. The high-pressure refrigerant compressed to discharge pressure is then discharged from the discharge port 32 into the discharge chamber 14. At this time, the lubricating oil 18 drawn into the compression chamber 12 together with the refrigerant is also discharged from the discharge port 32 into the discharge chamber 14 together with the high-pressure refrigerant.

[0105] Here, because the driving scroll 30 is driven to rotate about the drive axis O1, the centrifugal force of the rotating driving scroll 30 acts on the refrigerant discharged into the discharge chamber 14. As a result, the lubricating oil 18 contained in the refrigerant is separated from the refrigerant by centrifugal force. Then, the centrifugal force causes the lubricating oil 18 to splash outward within the discharge chamber 14, that is, toward the outer periphery wall 39a of the case 39.

[0106] In this way, the refrigerant discharged into the discharge chamber 14 flows through the discharge passage 390 and is discharged to the outside of the compressor through a pipe connected to the discharge communication port 69. At this time, in this compressor, the shaft seal member 63 seals the space between the discharge passage 390 and the scroll chamber 65, preventing the refrigerant flowing from the discharge passage 390 toward the discharge communication port 69 from circulating inside the scroll chamber 65.

[0107] Meanwhile, the lubricating oil 18 discharged from the discharge port 32 into the discharge chamber 14 together with the refrigerant is stored in the discharge chamber 14. The lubricating oil 18 in the discharge chamber 14 flows from the second supply passage 39c through the first supply passage 35a toward the return passage 37c, as shown by the solid arrows in Figures 1 and 2. In the return passage 37c, the lubricating oil 18 passes through the first passage 374 and reaches the recess 373.

[0108] Here, in this compressor, the front part of the first plain bearing 51 inserted into the insertion hole 37d faces the recess 373. For this reason, the first plain bearing 51 is suitably lubricated by the lubricating oil 18 in the recess 373. The lubricating oil 18 can also suitably lubricate the space between the first plain bearing 51 and the inner circumferential surface of the insertion hole 37d. As a result, insufficient lubrication of the first plain bearing 51 can be suitably prevented in this compressor.

[0109] Furthermore, in this compressor, the lubricating oil 18 in the recess 373 also effectively lubricates the second sliding bearing 13, the driven shaft 16, the rotation prevention pin 21, the ring 22, etc., and therefore, insufficient lubrication of the driven shaft 16, etc. can also be effectively prevented.

[0110] The lubricating oil 18 in the recess 373 flows from the second passage 375 to the annular passage 37g and the connecting passage 5. In this way, the lubricating oil 18 flows from the connecting passage 5 to the oil reservoir 3 and is stored in the oil reservoir 3.

[0111] Here, in this compressor, a gap (not shown) exists between the first plain bearing 51 and the inner circumferential surface of the insertion hole 37d, allowing the first plain bearing 51 to slide on the inner circumferential surface of the insertion hole 37d as the drive scroll 30 rotates. In this regard, in this compressor, the second passage 375 is located at a position that is radially outward of the cover body 37 with respect to the insertion hole 37d and the first plain bearing 51. Therefore, by flowing through the second passage 375, the lubricating oil 18 flows from within the recess 373 radially outward of the cover body 37 with respect to the insertion hole 37d and the first plain bearing 51, toward the connecting passage 5 and ultimately toward the oil reservoir chamber 3.

[0112] As a result, in this compressor, the lubricating oil 18 in the recess 373 lubricates the gap between the first plain bearing 51 and the inner circumferential surface of the insertion hole 37d, while preventing the lubricating oil 18 from leaking excessively into the scroll chamber 65 from the gap between the first plain bearing 51 and the inner circumferential surface of the insertion hole 37d. In this way, in this compressor, it is possible to sufficiently circulate the lubricating oil 18 from the return passage 37c to the oil storage chamber 3.

[0113] The lubricating oil 18 in the oil reservoir 3 is cooled and decompressed as it flows from the discharge chamber 14 through the second supply passage 39c, the first supply passage 35a, the return passage 37c, the annular passage 37g, and the connecting passage 5. Therefore, the lubricating oil 18 in the oil reservoir 3 is at a lower temperature and pressure than the lubricating oil 18 in the discharge chamber 14. The atmosphere in the oil reservoir 3 is also at a lower temperature and pressure than the atmosphere in the discharge chamber 14.

[0114] However, the oil reservoir 3 has a higher pressure atmosphere than the scroll chamber 65. Therefore, as shown by the solid arrow in Figure 1, the lubricating oil 18 in the oil reservoir 3 flows through the discharge passage 8 and flows into the scroll chamber 65. In this case, in this compressor, the flow rate of the lubricating oil 18 flowing from the oil reservoir 3 into the scroll chamber 65 is suitably adjusted depending on the size of the discharge passage 8.

[0115] In this manner, in this compressor, the electric motor 10 is lubricated by the lubricating oil 18 that flows from the oil reservoir 3 into the scroll chamber 65. The lubricating oil 18 in the scroll chamber 65 flows toward the suction passage 37e together with the refrigerant, and is then sucked back into the compression chamber 12 together with the refrigerant.

[0116] Thus, in this compressor, the driving scroll 30 and the driven scroll 40, including the inside of the compression chamber 12, are suitably lubricated by the lubricating oil 18. In this manner, in this compressor, the lubricating oil 18 flowing from the connecting passage 5 to the oil reservoir chamber 3 can be used to lubricate the electric motor 10, the driving scroll 30, and the driven scroll 40. Therefore, in this compressor, insufficient lubrication of the electric motor 10, the driving scroll 30, and the driven scroll 40 can also be suitably prevented.

[0117] Therefore, the compressor of the embodiment has excellent durability.

[0118] In particular, in this compressor, the second passage 375 of the return passage 37c and the connecting passage 5 are communicated with each other through the annular passage 37g. As a result, in this compressor, although the relative positions of the second passage 375 and the connecting passage 5 can change as the driving scroll 30 rotates, the connecting passage 5 and the second passage 375 can always be communicated with each other through the annular passage 37g regardless of such changes in relative positions.

[0119] Furthermore, in this compressor, the outer-circumferential sealing member 71 and the inner-circumferential sealing member 72 seal the gap between the second rear surface 372 of the cover main body 37a and the connecting end surface 82 of the second diameter portion 64b. This effectively prevents the lubricating oil 18 flowing from the annular passage 37g to the connecting passage 5 from leaking into the scroll chamber 65 from between the second rear surface 372 and the connecting end surface 82. This also allows the lubricating oil 18 to flow sufficiently from the return passage 37c to the oil storage chamber 3 in this compressor.

[0120] Here, because the outer-circumferential sealing member 71 and the inner-circumferential sealing member 72 are made of PTFE, the sliding properties between the outer-circumferential sealing member 71 and the inner-circumferential sealing member 72 and the connecting end surface 82 are ensured favorably. Therefore, in this compressor, the driving scroll 30 can be rotated favorably. Furthermore, because the outer-circumferential sealing member 71 and the inner-circumferential sealing member 72 are made of PTFE, the outer-circumferential sealing member 71 and the inner-circumferential sealing member 72 are less likely to wear even if the outer-circumferential sealing member 71 and the inner-circumferential sealing member 72 slide against the connecting end surface 82.

[0121] Furthermore, in this compressor, the lubricating oil 18 that has reached the oil reservoir 3 can be stored in the oil reservoir 3. This allows the lubricating oil 18 stored in the oil reservoir 3 to be suitably used to lubricate the electric motor 10, the driving scroll 30, the driven scroll 40, etc.

[0122] Furthermore, in this compressor, the protruding body 64 has a first diameter portion 64a and a second diameter portion 64b, and the second diameter portion 64b has a larger diameter than the first diameter portion 64a. Therefore, while the oil reservoir 3, the connecting passage 5, and the discharge passage 8 are formed in the second diameter portion 64b, the rigidity of the protruding body 64 is ensured by the second diameter portion 64b.

[0123] Furthermore, because the second diameter portion 64b is larger than the first diameter portion 64a, it is possible to easily form the oil reservoir 3 and the like, and it is also possible to increase the degree of freedom in designing the oil reservoir 3 and the like. Furthermore, because the second diameter portion 64b is larger than the first diameter portion 64a, it is possible to ensure that the connecting passage 5 opening at the connecting end face 82 is in good communication with the annular passage 37g and, by extension, the return passage 37c. On the other hand, because the first diameter portion 64a is smaller than the second diameter portion 64b, it is possible to prevent the first plain bearing 51 from becoming large in size in this compressor.

[0124] Furthermore, in this compressor, the discharge passage 390 is formed within the boss 39d, which makes it possible to easily form the discharge passage 390. Furthermore, in this compressor, the boss 39d is supported by the ball bearing 52, which allows the discharge passage 390 and the discharge communication port 69 to be suitably close to each other. Furthermore, in this compressor, the boss 39d is inserted into the shaft seal 63, which seals the discharge passage 390 and the discharge communication port 69 from the scroll chamber 65. For these reasons, in this compressor, it is possible to suitably prevent refrigerant flowing through the discharge passage 390 toward the discharge communication port 69 from leaking into the scroll chamber 65.

[0125] Furthermore, since the discharge chamber 14 is formed with a diameter larger than that of the ball bearing 52, the compressor can preferably secure a volume for the discharge chamber 14. As a result, the discharge chamber 14 preferably exerts a muffler effect on the refrigerant, thereby preferably reducing discharge pulsation when the refrigerant is discharged from the discharge communication port 69.

[0126] Although the present invention has been described above with reference to the examples, it goes without saying that the present invention is not limited to the above examples and can be modified and applied as appropriate within the scope of the invention.

[0127] For example, in the compressor of the embodiment, the first sliding bearing 51 provided on the outer peripheral surface of the first diameter portion 64a is the "bearing portion" of the present invention. However, instead, a ball bearing may be used as the "bearing portion" of the present invention. If a ball bearing is used, gaps may exist between the outer ring of the ball bearing and the inner peripheral surface of the insertion hole 37d, and between the inner ring of the ball bearing and the outer peripheral surface of the first diameter portion 64a, allowing the ball bearing to slide. In addition, relatively large gaps may exist between the outer ring and the bearing balls, and between the inner ring and the bearing balls. However, even if a ball bearing is used in this compressor, the lubricating oil 18 in the recess 373 can be effectively prevented from leaking into the scroll chamber 65 through these gaps.

[0128] Furthermore, as the "axial support portion" in the present invention, a coating layer that imparts slidability to the outer peripheral surface of the first diameter portion 64a or the inner peripheral surface of the insertion hole 37d may be provided, or a plating layer may be provided on the outer peripheral surface of the first diameter portion 64a or the inner peripheral surface of the insertion hole 37d.

[0129] In the compressor of the embodiment, the annular passage 37g is formed in the second rear surface 372 of the cover body portion 37a. However, this is not limiting, and the annular passage 37g may be formed in the connecting end surface 82 of the second diameter portion 64b.

[0130] Furthermore, the annular passage 37g may be omitted, and the second passage 375 and the connecting passage 5 may be intermittently connected to each other as the driving scroll 30 rotates.

[0131] Alternatively, the stator 17 may be fixed to the outer peripheral surface of the second diameter portion 64b, and the rotor 11 may be fixed to the extension portion 37b of the cover body 37 while surrounding the stator 17 from the outside.

[0132] In the compressor of the embodiment, the housing body 60 and the protruding body 64 are formed separately, and the protruding body 64 is fitted into the mounting recess 60c of the rear wall 60b. However, this is not limiting, and the protruding body 64 may be formed integrally with the rear wall 60b.

[0133] The present specification also includes the following inventions: (Supplementary Note 1) A double-rotating scroll compressor includes a housing, a drive mechanism, a driving scroll, a driven scroll, a driven mechanism, and a discharge chamber, wherein the housing has a scroll chamber in which the driving scroll and the driven scroll are housed, the driving scroll is rotationally driven about a drive axis by the drive mechanism, the driven scroll is rotationally driven by the drive scroll and the driven mechanism about a driven axis while being eccentric with respect to the driving scroll, the driving scroll and the driven scroll form compression chambers that compress refrigerant by the rotational driving and the rotational driven, and the refrigerant compressed in the compression chambers is discharged into the discharge chamber, wherein a protrusion is provided within the housing that protrudes into the scroll chamber in the direction of the drive axis toward the driving scroll and the driven scroll, the protrusion has a first diameter portion and a second diameter portion having a diameter larger than the first diameter portion, and the driving scroll has a cover body rotatably supported on the first diameter portion via a journal portion, a return passage formed in the cover body that communicates with the discharge chamber and allows the lubricating oil in the discharge chamber to flow toward the protruding body; a lubricating oil passage formed in the housing that is located radially inward of the drive mechanism and through which the lubricating oil can flow; a connecting passage formed in the second diameter portion that communicates between the outside of the second diameter portion and the lubricating oil passage and through which the lubricating oil can flow toward the lubricating oil passage; and the return passage and the connecting passage communicate with each other radially outside of the cover body relative to the support portion. (Supplementary Note 2) The double-rotary scroll compressor according to Supplementary Note 1, wherein the return passage has a first passage communicating with the discharge chamber and a second passage communicating with the first passage and the connecting passage, the second diameter portion has a first end surface facing the cover body in the drive shaft direction and having an opening for the connecting passage, the cover body has a second end surface facing the first end surface in the drive shaft direction and having an opening for the second passage, and an outer circumferential sealing member is provided between the first end surface and the second end surface, the outer circumferential sealing member extending in an annular shape and positioned radially outward of the connecting passage and the second passage, and sealing the gap between the first end surface and the second end surface.(Supplementary Note 3) The double-rotary scroll compressor according to Supplementary Note 2, wherein an inner circumferential sealing member is provided between the first end face and the second end face, the inner circumferential sealing member being located radially inward of the second passage and the connecting passage, extending in an annular shape and sealing the gap between the first end face and the second end face. (Supplementary Note 4) The double-rotary scroll compressor according to any one of Supplementary Notes 1 to 3, wherein the return passage has a first passage communicating with the discharge chamber and a second passage communicating with the first passage and the connecting passage, the second diameter portion has a first end face facing the cover body in the drive shaft direction and at which the connecting passage opens, the cover body has a second end face facing the first end face in the drive shaft direction and at which the second passage opens, and an annular passage extending in an annular shape and communicating with the connecting passage and the second passage is formed between the first end face and the second end face. (Supplementary Note 5) The double rotary scroll compressor according to any one of Supplementary Notes 1 to 4, wherein the lubricating oil passage is capable of storing the lubricating oil therein.

[0134] The present invention can be used in vehicle air conditioning systems and the like.

[0135] 3 Oil storage chamber (lubricating oil passage) 5 Connecting passage 6 Housing 10 Electric motor (driving mechanism) 12 Compression chamber 14 Discharge chamber 18 Lubricating oil 20 Driven mechanism 30 Drive scroll 37 Cover body 37c Circulation passage 37g Annular passage 39d Boss (supported member) 40 Driven scroll 51 First plain bearing (bearing portion) 52 Ball bearing (bearing) 64 Projecting body 64a First diameter portion 64b Second diameter portion 65 Scroll chamber 82 Connecting end surface (second end surface) 71 Outer peripheral side sealing member 72 Inner peripheral side sealing member 372 Second rear surface (first end surface) 374 First passage 375 Second passage O1 Drive axis O2 Driven axis

Claims

1. A double-rotating scroll compressor comprising a housing, a drive mechanism, a driving scroll, a driven scroll, a driven mechanism, and a discharge chamber, wherein the housing has a scroll chamber in which the driving scroll and the driven scroll are housed, the driving scroll is rotationally driven about the drive axis by the drive mechanism, the driven scroll is rotationally driven by the drive scroll and the driven mechanism about the driven axis while being eccentric with respect to the driving scroll, the driving scroll and the driven scroll form a compression chamber that compresses a refrigerant by the rotational driving and the rotational driven, and the refrigerant compressed in the compression chamber is discharged into the discharge chamber, wherein a protrusion is provided within the housing that protrudes into the scroll chamber in the direction of the drive axis toward the driving scroll and the driven scroll, the protrusion has a first diameter portion and a second diameter portion having a diameter larger than the first diameter portion, and the driving scroll has a cover body rotatably supported on the first diameter portion via a journal portion, a return passage formed in the cover body that communicates with the discharge chamber and allows the lubricating oil in the discharge chamber to flow toward the protruding body; a lubricating oil passage formed in the housing that is located radially inward of the drive mechanism and through which the lubricating oil can flow; a connecting passage formed in the second diameter portion that communicates between the outside of the second diameter portion and the lubricating oil passage and through which the lubricating oil can flow toward the lubricating oil passage; and the return passage and the connecting passage communicate with each other radially outside of the cover body relative to the support portion.

2. A double-rotating scroll compressor according to claim 1, wherein the return passage has a first passage communicating with the discharge chamber and a second passage communicating with the first passage and the connecting passage, the second diameter portion has a first end face facing the cover body in the direction of the drive shaft and into which the connecting passage opens, the cover body has a second end face facing the first end face in the direction of the drive shaft and into which the second passage opens, and an outer peripheral sealing member is provided between the first end face and the second end face, extending in an annular shape and positioned radially outward of the connecting passage and the second passage, and sealing the gap between the first end face and the second end face.

3. A double-rotating scroll compressor as described in claim 2, wherein an inner sealing member is provided between the first end face and the second end face, extending in an annular shape and positioned radially inward of the second passage and the connecting passage, and sealing the gap between the first end face and the second end face.

4. A double-rotating scroll compressor according to claim 1 or 2, wherein the return passage has a first passage communicating with the discharge chamber and a second passage communicating with the first passage and the connecting passage, the second diameter portion has a first end face facing the cover body in the direction of the drive shaft and into which the connecting passage opens, the cover body has a second end face facing the first end face in the direction of the drive shaft and into which the second passage opens, and an annular passage extending annularly and communicating with the connecting passage and the second passage is formed between the first end face and the second end face.

5. A double rotary scroll compressor according to claim 1 or 2, wherein said lubricating oil passage is capable of storing said lubricating oil therein.

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