Co-rotating scroll 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). The fluid compressed in the compression chamber (12) is discharged to the discharge chamber (14). The housing (6) has a protruding body (64) provided therein. The protruding body (64) has a first diameter part (64a) and a second diameter part (64b) having a larger diameter than the first diameter part (64a). The drive scroll (30) has a cover body (37) that is rotatably supported by the first diameter part (64a) via a bearing (51). Inside the second diameter part (64b) is formed a first fluid passage (3) through which a specific fluid having a lower temperature and a lower pressure than the fluid in the discharge chamber (14) can flow.

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 region. The housing has a scroll chamber that houses the drive mechanism, the drive scroll, and the driven scroll. A fluid is drawn into the scroll chamber from outside the housing. In this document, the fluid is specifically a refrigerant.

[0003] The drive mechanism has a stator and a rotor. The stator is fixed to the housing. 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. This allows the drive scroll to be rotationally driven about the drive axis by rotation of the rotor. The driven scroll is eccentric with respect to the drive scroll and can be rotationally driven by the drive scroll and driven mechanism about the driven axis. The drive scroll and driven scroll form a compression chamber that compresses a fluid by rotational driving and rotational following. The discharge region is specifically a discharge port. The discharge region is formed in the driven scroll and is connected to the compression chamber.

[0004] This compressor also has a protrusion provided on the housing. The protrusion is formed in a generally cylindrical shape with a constant outer diameter and 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 bearing is provided between the inner peripheral surface of the extension portion and the outer peripheral surface of the protrusion. Thus, the protrusion rotatably supports the cover body via the bearing. A fluid passage extending in the drive axial direction is formed inside the protrusion. The fluid passage communicates with the discharge region on one side in the drive axial direction and with the outside of the housing on the other side in the drive axial direction.

[0005] In this compressor, the fluid compressed in the compression chamber is discharged to the discharge region, and the fluid discharged to the discharge region flows through a fluid passage and is then discharged to the outside of the housing, i.e., to the outside of the compressor.

[0006] Japanese Unexamined Patent Publication No. 2-227575

[0007] However, in the conventional compressor, the outer diameter of the protrusion is not large enough, and a fluid passage is formed inside the protrusion, which makes it difficult to ensure the rigidity of the protrusion, and this raises concerns about a decrease in the durability of the protrusion and, ultimately, the compressor.

[0008] To address this issue, it is conceivable to increase the outer diameter of the protrusion to ensure its rigidity. However, since the protrusion supports the cover while entering the extension portion of the cover, increasing the outer diameter of the protrusion requires correspondingly increasing the size of the bearing and the cover. This inevitably leads to an increase in the size of the compressor.

[0009] Furthermore, in this compressor, the fluid compressed in the compression chamber flows through the fluid passage. Here, the fluid compressed in the compression chamber is at high temperature and pressure, and the fluid flowing through the fluid passage increases the temperature of the protrusion and the bearing. This tends to reduce the durability of the bearing, and in this respect, there is also concern about a reduction in durability in this compressor.

[0010] The present invention has been made in view of the above-described conventional circumstances, and an object to be achieved is to provide a double-rotation scroll compressor that is excellent in durability and can be prevented from becoming large in size.

[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 region, 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 fluid by the rotational driving and the rotational driven, and the discharge region discharges the fluid compressed in the compression chambers, 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, and the protrusion has a first diameter portion and a second diameter portion that is larger in diameter than the first diameter portion, and the driving scroll or the driven scroll has a cover body that is rotatably supported on the first diameter portion via a bearing, The second diameter portion is characterized in that a fluid passage is formed inside the second diameter portion, which communicates with the outside of the second diameter portion and through which a specific fluid having a lower temperature and pressure than the fluid in the discharge area can flow.

[0012] In the double-rotary scroll compressor of the present invention, the protruding body has a first diameter portion and a second diameter portion, and the first diameter portion supports the cover body via a bearing. Meanwhile, the second diameter portion has a larger diameter than the first diameter portion. A fluid passage is formed inside the second diameter portion. Therefore, compared to a case where the protruding body is formed only with the first diameter portion and a fluid passage is formed inside the first diameter portion, in this compressor, the rigidity of the protruding body can be more easily ensured by the second diameter portion.

[0013] Furthermore, because the cover body is rotatably supported on the first diameter portion via the bearing, the bearing and cover body are unlikely to become large even if the second diameter portion has a larger diameter than the first diameter portion. Furthermore, because the second diameter portion is larger than the first diameter portion, the degree of freedom in designing the fluid passages, including their size, is increased.

[0014] The fluid passage is filled with a specific fluid that is lower in temperature and pressure than the fluid in the discharge region. Therefore, in this compressor, the specific fluid in the fluid passage is less likely to heat the protrusion, including the second diameter portion. As a result, in this compressor, the temperature rise of the bearing due to the temperature rise of the protrusion can also be suppressed.

[0015] Therefore, the double rotation scroll compressor of the present invention has excellent durability and can be prevented from becoming large in size.

[0016] In the compressor of the present invention, the housing and the protrusion may be formed separately, and the second diameter portion is preferably fixed to the housing.

[0017] In this case, the housing and the protrusion can be formed from different materials, which makes it easier to ensure the rigidity and durability of the protrusion. Furthermore, in this compressor, compared to when the housing and the protrusion are formed integrally, the formation of the fluid passages can be simplified and the degree of freedom in the design of the protrusion can be increased.

[0018] In the compressor of the present invention, the specific fluid may be a lubricating oil contained in the fluid. The fluid passage may be capable of storing the lubricating oil while allowing it to flow. The protrusion may be formed with a first passage connected to the fluid passage and allowing the lubricating oil to flow through the fluid passage, and a second passage connected to the fluid passage at a position different from the first passage and allowing the lubricating oil in the fluid passage to flow out of the fluid passage. The cover preferably is formed with a return passage communicating with the discharge region and the first passage and allowing the lubricating oil to flow from the discharge region to the first passage, and a supply passage communicating with the second passage and the compression chamber and allowing the lubricating oil to flow from the second passage to the compression chamber.

[0019] In this case, the lubricating oil in the discharge region flows to the fluid passage through the return passage formed in the cover body and the first passage formed in the protruding body, and is stored in the fluid passage. As a result, in this compressor, the fluid passage can be used as a lubricating oil storage chamber. Furthermore, the lubricating oil in the fluid passage is supplied to the compression chamber through the first passage formed in the protruding body and the supply passage formed in the cover body. In this way, in this compressor, the driving scroll, the driven scroll, etc., as well as the compression chamber can be suitably lubricated, thereby improving the durability of the compressor.

[0020] Furthermore, by using the fluid passage as a reservoir for lubricating oil, it is not necessary to provide a dedicated space for the oil reservoir in the compressor, separate from the protrusion, which also helps to prevent the compressor from becoming too large.

[0021] In this case, the drive scroll may have a cover body. The driven scroll may have an accommodating recess facing the first diameter portion in the drive axial direction. A bushing may be accommodated in the accommodating recess. The bushing may be provided with a shaft body extending in the drive axial direction and inserted into the first diameter portion, and a bushing passage may be formed in the bushing to circulate the lubricating oil from the return passage to the first passage into the accommodating recess. It is preferable that the shaft body has an axial hole formed therein that extends in the drive axial direction, communicates with the accommodating recess and the fluid passage, and circulates the lubricating oil from the accommodating recess to the fluid passage.

[0022] This allows the bushing to be suitably lubricated by the lubricating oil, thereby increasing the durability of the bushing.

[0023] In the compressor of the present invention, the housing may be formed with an intake communication port for drawing fluid into the scroll chamber from outside the housing. The specific fluid may be lubricating oil contained in the fluid. The second diameter portion may be formed with a communication passage that connects to the fluid passage and communicates with a location in the scroll chamber that is lower than the second diameter portion in the direction of gravity, and that circulates the lubricating oil in the scroll chamber toward the fluid passage. It is also preferable that the cover body be formed with an intake passage that communicates with the fluid passage and the compression chamber, and that circulates the lubricating oil that has circulated through the fluid passage toward the compression chamber.

[0024] Because lubricating oil is a liquid, it tends to accumulate in the scroll chamber at a lower position in the direction of gravity. In this compressor, a communication passage is formed in the second diameter portion, and this communication passage communicates with a location in the scroll chamber that is lower in the direction of gravity than the second diameter portion. This allows the communication passage to efficiently circulate the lubricating oil in the scroll chamber to the fluid passage. Furthermore, in this compressor, the suction passage formed in the cover body allows the lubricating oil that has circulated through the fluid passage to circulate toward the compression chamber. This allows the lubricating oil to efficiently lubricate the compression chamber, as well as the driving scroll, driven scroll, etc.

[0025] In this case, the cover body may be formed with an extension portion that is cylindrical and extends in the drive shaft direction and that covers the second diameter portion from the outside. A gap may be provided between the extension portion and the second diameter portion that communicates with the scroll chamber and allows fluid to flow through the scroll chamber. The suction passage preferably allows the fluid that has flowed through the gap to flow toward the compression chamber together with the lubricating oil.

[0026] This makes it possible to suitably suck the fluid that has flowed through the gap between the extension portion and the second diameter portion, i.e., the fluid inside the scroll chamber, into the compression chamber through the suction passage without forming a dedicated passage for sucking the fluid inside the scroll chamber into the compression chamber.

[0027] In the compressor of the present invention, the housing may be formed with a connecting passage connecting the fluid passage to the outside of the housing. The specific fluid may be an intake refrigerant drawn into the fluid passage through the connecting passage. The fluid passage may separate the intake refrigerant into a gas phase refrigerant and a liquid phase refrigerant and may be capable of storing the liquid refrigerant. The connecting passage may open into the housing at a location above the fluid passage in the direction of gravity. The second diameter portion may be formed with a first refrigerant passage that circulates the gas refrigerant in the fluid passage into the scroll chamber. It is also preferable that the cover body be formed with a second refrigerant passage that communicates with the scroll chamber and the compression chamber and circulates the gas refrigerant in the scroll chamber toward the compression chamber.

[0028] In this case, the fluid passage can be used as a gas-liquid separation chamber for the suction refrigerant. By storing the liquid refrigerant in the fluid passage, the liquid refrigerant can be effectively prevented from being drawn into the compression chamber. Furthermore, by using the fluid passage as a gas-liquid separation chamber for the suction refrigerant, this compressor does not need to provide a dedicated space for the gas-liquid separation chamber in addition to the protruding body. This prevents the compressor from becoming larger. Furthermore, in this compressor, the connecting passage opens into the housing at a location higher than the fluid passage in the direction of gravity, thereby effectively preventing the liquid refrigerant stored in the fluid passage from flowing back through the connecting passage.

[0029] In the compressor of the present invention, the drive scroll may have a cover body. The cover body may have a cylindrical extension extending in the drive shaft direction and covering the second diameter portion from the outside. The drive mechanism preferably has a stator fixed to the housing and disposed within the scroll chamber, and a rotor fixed to the extension and disposed within the stator.

[0030] In this case, by disposing the drive mechanism in the scroll chamber, it is not necessary to provide a dedicated space for the drive mechanism in the housing separate from the scroll chamber. Also, by fixing the rotor to the extension of the cover body, the cover body and the rotor can be easily fixed together. Therefore, in this compressor, the rotation of the rotor can be suitably driven to rotate the drive scroll.

[0031] In the compressor of the present invention, the drive scroll may have a cover body, and the drive mechanism preferably has a stator fixed to the second diameter portion and disposed within the scroll chamber, and a rotor fixed to the cover body within the scroll chamber and covering the stator from the outside.

[0032] In this case, there is no need to provide a dedicated space for the drive mechanism in the housing, separate from the scroll chamber. Also, since the second diameter portion has a larger diameter than the first diameter portion, the stator can be suitably fixed to the second diameter portion.

[0033] The double-rotation scroll compressor of the present invention is excellent in durability and can be prevented from becoming large in size.

[0034] Fig. 1 is a cross-sectional view of a compressor according to a first embodiment. Fig. 2 is a cross-sectional view of a compressor according to a second embodiment. Fig. 3 is a cross-sectional view of a compressor according to a third embodiment. Fig. 4 is a cross-sectional view of a compressor according to a fourth embodiment.

[0035] Hereinafter, first to fourth embodiments of the present invention will be described with reference to the drawings. The double rotary scroll compressors of the first to fourth embodiments are mounted in a vehicle (not shown) and form an air conditioning system for the vehicle.

[0036] As shown in Figure 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" in the present invention. The discharge chamber 14 is an example of the "discharge region" in the present invention.

[0037] In this embodiment, the front-rear direction and the up-down direction of the compressor are defined by solid arrows shown in FIG. 1 . In FIG. 2 and subsequent figures, the front-rear direction and the up-down direction of the compressor are defined corresponding to FIG. 1 . The front-rear direction and the up-down direction are perpendicular to each other. The direction from top to bottom corresponds to the direction of gravity in the present invention. Therefore, when this compressor is mounted on a vehicle, gravity acts from top to bottom on the paper of FIG. 1 . Note that these front-rear directions and the like are merely examples for the sake of convenience, and the compressor's posture can be changed as appropriate depending on the vehicle in which it is mounted.

[0038] 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.

[0039] 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.

[0040] 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).

[0041] 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.

[0042] A 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.

[0043] 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 the insertion hole 37d (described later). The first diameter portion 64a is formed with a pin hole 4 and a first passage 5. The pin hole 4 and the first passage 5 are disposed apart from each other and each penetrate the first diameter portion 64a in the drive shaft O1 direction. As a result, the pin hole 4 and the first passage 5 each open to the front end surface of the first diameter portion 64a. The pin hole 4 is formed with a larger diameter than the first passage 5. The pin hole 4 and the first passage 5 may be formed with the same diameter, or the first passage 5 may be formed with a larger diameter than the pin hole 4.

[0044] 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" in the present invention. Note that instead of the first plain bearing 51, a ball bearing may be provided on the outer peripheral surface of the first diameter portion 64a.

[0045] 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.

[0046] 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 is connected to the first diameter portion 64a. The flange portion 642 has a larger diameter than the main body portion 641 and extends outward from the main body portion 641 in the radial direction of the second diameter portion 64b.

[0047] The second diameter portion 64b is formed with the first fluid passage 3, the second fluid passage 7, the second passage 8, and the communication passage 9. The first fluid passage 3 and the second fluid passage 7 are examples of the "fluid passage" in the present invention.

[0048] The first fluid passage 3 has a larger diameter than the pin hole 4 and the first passage 5, extends inside the main body portion 641 and the flange portion 642 in the direction of the drive axis O1, and opens at the rear end surface of the flange portion 642. The first fluid passage 3 is recessed forward from the rear end of the flange portion 642, i.e., the rear end of the second diameter portion 64b, and does not pass through the second diameter portion 64b. The first fluid passage 3 is in communication with the pin hole 4 and the first passage 5, respectively.

[0049] The second fluid passage 7 has a smaller diameter than the first fluid passage 3, extends inside the main body portion 641 and the flange portion 642 in the direction of the drive axis O1, and opens at the front end surface of the main body portion 641. Here, the second fluid passage 7 is disposed radially outward of the second diameter portion 64b relative to the first fluid passage 3, and is not in communication with the first fluid passage 3. The second fluid passage 7 is recessed rearward from the front end of the second diameter portion 64b and does not penetrate the flange portion 642. In other words, the first fluid passage 3 and the second fluid passage 7 are recessed in opposite directions relative to the second diameter portion 64b in the direction of the drive axis O1.

[0050] The second passage 8 is formed in the main body portion 641 and is disposed at a location radially inward of the second diameter portion 64b relative to the second fluid passage 7. The second passage 8 penetrates the main body portion 641 in the direction of the drive axis O1. As a result, the front end of the second passage 8 opens at the front end surface of the main body portion 641 and the rear end thereof communicates with the first fluid passage 3.

[0051] The communication passage 9 is formed in the flange portion 642. The communication passage 9 extends inside the flange portion 642 in the radial direction of the second diameter portion 64b. As a result, one end of the communication passage 9 is connected to the rear portion of the second fluid passage 7, and the other end opens to the outer circumferential surface of the flange portion 642. The communication passage 9 may also be formed in the main body portion 641.

[0052] The protrusion 64 is fixed to the rear wall 60b by fitting the flange portion 642 into the mounting recess 60c. Thus, in the protrusion 64, the rear end of the first fluid passage 3 is closed by the rear wall 60b.

[0053] 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.

[0054] 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 shaft seal member 63 is disposed inside the support portion 66 at a position forward of the ball bearing 52. The shaft seal member 63 is formed in an annular shape. Note that a sliding bearing may be provided inside the support portion 66 instead of the ball bearing 52.

[0055] 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).

[0056] 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.

[0057] 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 the suction port 68. As a result, refrigerant is drawn into the scroll chamber 65 from outside the housing 6 through the suction port 68. The refrigerant is an example of the "fluid" in the present invention. The refrigerant contains lubricating oil 18.

[0058] 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. In the protrusion 64, the second diameter portion 64b separates the scroll chamber 65 from the first fluid passage 3.

[0059] In addition, in the protrusion 64, the other end of the communication passage 9 communicates with the scroll chamber 65. In this case, the other end of the communication passage 9 faces downward from the scroll chamber 65. As a result, the other end of the communication passage 9 communicates with a location in the scroll chamber 65 that is lower in the direction of gravity than the second diameter portion 64b.

[0060] 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.

[0061] 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.

[0062] 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 is composed of a plurality of permanent magnets corresponding to the stator 17 and laminated steel plates that secure the permanent magnets.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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 on the central side of the drive end plate 31 and protrudes in a spiral shape from the spiral center toward the outer periphery.

[0067] 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.

[0068] A first oil passage 35a is formed in the drive end plate 31 and the drive peripheral wall 35. The first oil 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 oil passage 35a opens at the first front surface 311 of the drive end plate 31. The rear end of the first oil passage 35a opens at the rear end surface of the drive peripheral wall 35.

[0069] The cover body 37 is composed of 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. As shown in FIG. 1 , 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.

[0070] The cover body 37a is formed with a recess 37c, an insertion hole 37d, an intake passage 37e, a return passage 37f, and a first bolt hole 37g. The intake passage 37e is an example of the "supply passage" according to the present invention.

[0071] The recess 37c is located approximately in the center of the second front surface 371 and is recessed rearward from the second front surface 371. 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 communicates with the recess 37c at its front end. The insertion hole 37d is formed to have approximately the same diameter as the outer diameter of the first plain bearing 51.

[0072] The suction passage 37e is disposed at a location radially outward of the cover body 37 relative to the recess 37c. The suction passage 37e penetrates the cover main body 37a in the front-rear direction, with its front end opening to the second front surface 371 and its rear end opening to the second rear surface 372. The suction passage 37e is inclined radially inward of the cover body 37 from the front to the rear. The rear end of the suction passage 37e opens to the second rear surface 372 at a location radially inward of the cover body 37 relative to the extension portion 37b.

[0073] One end of the return passage 37f opens to the second front surface 371 at a location different from the suction passage 37e. The return passage 37f extends inside the cover body 37a and has the other end opening into the recess 37c. As a result, the return passage 37f is not in communication with the suction passage 37e but is in communication with the recess 37c. The first bolt hole 37g is located at a location radially outward of the cover body 37 relative to the suction passage 37e. The first bolt hole 37g penetrates the cover body 37a in the direction of the drive axis O1. Note that multiple first bolt holes 37g are formed in the cover body 37a.

[0074] Additionally, multiple rings 22 are attached to the cover main body 37a between the recess 37c and the suction passage 37e. Although not shown in detail, the rings 22 are arranged at equal intervals around the circumferential direction of the recess 37c while facing forward, and surround the recess 37c from the outside. In this embodiment, there are six rings 22. Also, FIGS. 1 to 4 show one each of each ring 22 and the first bolt hole 37g.

[0075] 1, the extension portion 37b is formed integrally with the cover main body portion 37a and extends cylindrically rearward from the second rear surface 372 in the direction of the drive axis O1. 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.

[0076] The cover body 37 has the second front surface 371 of the cover main body portion 37a abutting against the rear end surface of the drive peripheral wall 35. In this state, the first bolts 34a are inserted into the first bolt holes 37g, respectively, and the first bolts 34a are 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 return passage 37f is aligned with the rear end of the first oil passage 35a, and the return passage 37f and the first oil passage 35a are in communication with each other.

[0077] The case 39 is a cylindrical member with a bottom and includes an outer peripheral wall 39 a and a front wall 39 b. The outer peripheral wall 39 a is cylindrical and has its center on the drive axis O1. The outer diameter of the outer peripheral wall 39 a is approximately the same as the diameter of the drive end plate 31.

[0078] A second oil passage 39c is formed in the outer peripheral wall 39a. One end of the second oil passage 39c opens to the inner peripheral surface of the outer peripheral wall 39a. The second oil passage 39c extends inside the outer peripheral wall 39a and the other end opens to the rear end surface of the outer peripheral wall 39a.

[0079] 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. A boss 39d is formed on the front wall 39b. 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 a diameter generally equal to the inner diameters of the ball bearing 52 and 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.

[0080] 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 oil passage 39c. A plurality of second bolt holes 39e are formed in the outer peripheral wall 39a and the front wall 39b. FIGS. 1 to 4 show only one of the plurality of second bolt holes 39e.

[0081] 1 , the rear end surface 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.

[0082] 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 communicates with the discharge port 32 and also with the discharge passage 390. Furthermore, one end of a second oil passage 39c communicates with the discharge chamber 14.

[0083] Furthermore, by fixing the case 39 to the drive end plate 31, the other end of the second oil passage 39c is aligned with the front end of the first oil passage 35a. This allows the second oil passage 39c to communicate with the first oil passage 35a. As a result, in the drive scroll 30, the return passage 37f communicates with the discharge chamber 14 through the first oil passage 35a and the second oil passage 39c.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] A bushing 53 is accommodated in the accommodation recess 15 via the second plain bearing 13. A bushing passage 54 is formed in the bushing 53. The bushing passage 54 passes through the bushing 53 in the direction of the drive axis O1 and communicates with the inside of the accommodation recess 15.

[0088] A driven pin 55 is inserted into the bushing 53 at a position different from the bushing passage 54. More specifically, the driven pin 55 is inserted into the bushing 53 at a position eccentric to the center of the bushing 53, i.e., the driven axis O2. The driven pin 55 is an example of a "shaft" in the present invention. The driven pin 55 protrudes rearward from the bushing 53 and, by extension, from the driven end plate 41. The driven pin 55 also has a shaft hole 55a formed therein. The shaft hole 55a passes through the driven pin 55 in the direction of the drive axis O1. As a result, the front end of the driven pin 55 communicates with the inside of the accommodating recess 15.

[0089] Furthermore, a rotation-preventing pin 21 is fixed to the driven end plate 41 at a position facing the ring 22. The rotation-preventing pin 21 protrudes rearward from the third rear surface 412. Six rotation-preventing pins 21 are fixed to the driven end plate 41, the same number as the number of rings 22. Also, only one of the rotation-preventing pins 21 is shown in FIGS. 1 to 4.

[0090] 1, the rotation-preventing pins 21 and the rings 22 constitute a 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.

[0091] 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 central side of the driven end plate 41 and extends spirally from the spiral center toward the outer periphery.

[0092] In this compressor, the driven scroll 40 is housed within the driving scroll 30, and the driving scroll 33 of the driving scroll 30 and the driven scroll 43 of the driven scroll 40 are meshed together. As a result, the driving scroll 33 and the driven scroll 43 face each other to form a compression chamber 12.

[0093] 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.

[0094] 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.

[0095] Furthermore, by assembling the driving scroll 30 and the driven scroll 40, the accommodating recess 15 of the driven end plate 41 and the bushing 53 face the recess 37c of the cover body 37. As a result, the bushing passage 54 communicates with the inside of the recess 37c.

[0096] 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.

[0097] 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. Here, since the extension portion 37b is formed with a larger diameter than the main body portion 641, a gap S is formed between the inner circumferential surface of the extension portion 37b and the main body portion 641. The gap S is in communication with the scroll chamber 65.

[0098] 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 by the first diameter portion 64a via the first plain bearing 51. The pin hole 4 and the first passage 5 each face the bushing 53 in the front-rear direction through the recess 37c. In this way, the pin hole 4 and the first passage 5 communicate with the recess 37c. As a result, the first fluid passage 3 and the return passage 37f communicate with each other through the recess 37c, the pin hole 4, and the first passage 5.

[0099] Furthermore, in the driving scroll 30, the second passage 8 faces into the gap S. As a result, the first fluid passage 3 and the gap S communicate with each other through the second passage 8. Also, in the driving scroll 30, the front end of the second fluid passage 7 faces into the gap S, so that the second fluid passage 7 communicates with the gap S.

[0100] Furthermore, 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 around the drive axis O1.

[0101] 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. As a result, the discharge chamber 14 and the discharge communication port 69 communicate with each other through the discharge passage 390. The shaft seal member 63 seals the discharge passage 390 and the discharge communication port 69 from the scroll chamber 65.

[0102] 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 about the driven axis O2 with respect to the first diameter portion 64a of the protruding body 64. In other words, unlike the driving scroll 30, the driven scroll 40 is supported in the housing 6 by the protruding body 64 alone so as to be rotatable about the driven axis O2.

[0103] Furthermore, by inserting the driven pin 55 into the pin hole 4 , the first fluid passage 3 and the accommodation recess 15 communicate with each other through the shaft hole 55 a and the pin hole 4 .

[0104] In the compressor configured as described above, as shown by the dashed arrow in FIG. 1 , 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.

[0105] 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.

[0106] The refrigerant drawn into the scroll chamber 65 flows through the suction passage 37e via the gap S. The refrigerant drawn into the scroll chamber 65 contains lubricating oil 18. Therefore, some of the lubricating oil 18 contained in the refrigerant is accumulated in the lower part of the scroll chamber 65 due to gravity. As a result, the lubricating oil 18 lubricates the electric motor 10.

[0107] Here, the protrusion 64 is fixed to the housing main body 60 and therefore does not rotate. Therefore, when the drive scroll 30 is driven to rotate about the drive axis O1, the extension portion 37b rotates relative to the second diameter portion 64b of the protrusion 64 about the drive axis O1. As a result, of the refrigerant flowing through the gap S toward the suction passage 37e, liquid refrigerant, which is in liquid phase, is vaporized by shear force while flowing through the gap S. Therefore, the refrigerant that reaches the suction passage 37e becomes gas refrigerant, which is in almost gas phase. In other words, the liquid refrigerant has difficulty reaching the suction passage 37e and therefore has difficulty flowing through the suction passage 37e.

[0108] Meanwhile, the refrigerant that reaches the suction passage 37e from the gap S is drawn from the suction passage 37e through the suction section 30a into the compression chamber 12. The compression chamber 12 then 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 the discharge pressure is then discharged from the discharge port 32 into the discharge chamber 14.

[0109] Here, the lubricating oil 18 that is not stored in the scroll chamber 65 and that is drawn into the compression chamber 12 together with the refrigerant is discharged from the discharge port 32 into the discharge chamber 14 together with the high-pressure refrigerant. Furthermore, because the drive scroll 30 is driven to rotate about the drive axis O1, the lubricating oil 18 discharged into the discharge chamber 14 is centrifuged from the refrigerant. At this time, the centrifugal force causes the lubricating oil 18 in the discharge chamber 14 to splash outward within the discharge chamber 14, that is, toward the outer periphery wall 39a of the case 39.

[0110] 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.

[0111] 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 then flows from the second oil passage 39c through the first oil passage 35a toward the return passage 37f, as shown by the solid arrow in FIG. 1 . The lubricating oil 18 flowing through the return passage 37f reaches the recess 37c. As a result, some of the lubricating oil 18 in the recess 37c flows through the first passage 5 and into the first fluid passage 3 while lubricating the gap between the first plain bearing 51 and the first diameter portion 64a of the protrusion 64, the gap between the cover main body 37a and the driven end plate 41, the gap between the bushing 53 and the second plain bearing 13, and the gap between the rotation-preventing pin 21 and the ring 22, among other areas.

[0112] Furthermore, the lubricating oil 18 in the recess 37c flows through the bushing passage 54, and thereby reaches the space between the bushing 53 and the installation recess 15. As a result, the lubricating oil 18 flows from the shaft hole 55a through the pin hole 4 and into the first fluid passage 3, while lubricating the space between the second sliding bearing 13 and the bushing 53.

[0113] In this way, the lubricating oil 18 that has reached the first fluid passage 3 through the pin hole 4 and the first passage 5 is stored in the first fluid passage 3. As a result, the first fluid passage 3 functions as an oil storage chamber for the lubricating oil 18.

[0114] Here, the temperature of the lubricating oil 18 in the first fluid passage 3 drops and the pressure thereof decreases as it flows from the discharge chamber 14 through the second oil passage 39c, the first oil passage 35a, the return passage 37f, the recess 37c, etc. Therefore, the temperature and pressure of the lubricating oil 18 in the first fluid passage 3 are lower than those of the lubricating oil 18 in the discharge chamber 14. The atmosphere in the first fluid passage 3 is also lower in temperature and pressure than those in the discharge chamber 14.

[0115] However, the first fluid passage 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 first fluid passage 3 flows through the second passage 8 and reaches the gap S, that is, the outside of the first fluid passage 3.

[0116] 1, the lubricating oil 18 stored in the scroll chamber 65 flows from the communication passage 9 through the second fluid passage 7 and into the gap S. Here, the lubricating oil 18 in the scroll chamber 65 is also at a lower temperature and pressure than the lubricating oil 18 in the discharge chamber 14.

[0117] As a result, the lubricating oil 18 that has flowed through the first fluid passage 3 and the second fluid passage 7 reaches the suction passage 37e together with the refrigerant flowing through the gap S toward the suction passage 37e, and is sucked into the compression chamber 12 together with the refrigerant. In this manner, 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.

[0118] As described above, 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. Furthermore, the first fluid passage 3, the second fluid passage 7, and the communication passage 9 are formed inside the second diameter portion 64b. Therefore, compared to a case where the protruding body 64 is formed only with the first diameter portion 64a and the first fluid passage 3, the second fluid passage 7, and the communication passage 9 are formed inside the first diameter portion 64a, in this compressor, even though the first fluid passage 3, the second fluid passage 7, and the communication passage 9 are formed, the rigidity of the protruding body 64 is more easily ensured by the second diameter portion 64b.

[0119] Furthermore, because the cover body 37 is rotatably supported on the first diameter portion 64a via the first plain bearing 51, the size of the first plain bearing 51 is not affected by the size of the second diameter portion 64b, even if the second diameter portion 64b is larger than the first diameter portion 64a. Furthermore, the extension portion 37b has a smaller diameter than the cover main body portion 37a. For these reasons, the first plain bearing 51 and the cover body 37 are less likely to be large in this compressor. Furthermore, because the second diameter portion 64b is larger than the first diameter portion 64a, this compressor offers greater design freedom for the first fluid passage 3, the second fluid passage 7, and the communication passage 9, including the sizes of the first fluid passage 3 and the second fluid passage 7. As a result, this compressor is able to store a sufficient amount of lubricating oil 18 in the first fluid passage 3, and is able to smoothly circulate the lubricating oil 18 through the second fluid passage 7 and the communication passage 9.

[0120] Lubricating oil 18 that is at a lower temperature and pressure than lubricating oil 18 in the discharge chamber 14 flows through these first fluid passage 3, second fluid passage 7, and communication passage 9. For this reason, in this compressor, the protruding body 64, including the second diameter portion 64b, is less likely to be heated by the lubricating oil 18 that flows through the first fluid passage 3, second fluid passage 7, and communication passage 9. As a result, in this compressor, a temperature rise in the first sliding bearing 51 caused by a temperature rise in the protruding body 64 is also suppressed.

[0121] Therefore, the compressor of the first embodiment has excellent durability and can be prevented from becoming large in size.

[0122] In particular, in this compressor, the lubricating oil 18 in the first fluid passage 3 can be drawn into the compression chamber 12 together with the refrigerant flowing through the suction passage 37e. As a result, the suction passage 37e not only draws the refrigerant into the compression chamber 12, but also functions as a supply passage that supplies the lubricating oil 18 to the compression chamber 12. Therefore, in this compressor, the lubricating oil 18 can be used to suitably lubricate the compression chamber 12 without forming a dedicated supply passage in the cover body 37.

[0123] Furthermore, in this compressor, the lubricating oil 18 that reaches the recess 37c from the return passage 37f can also suitably lubricate the gap between the first plain bearing 51 and the first diameter portion 64a of the protrusion 64, and the gap between the cover main body 37a and the driven end plate 41. In addition, in this compressor, the lubricating oil 18 that reaches the recess 37c from the return passage 37f flows through the bush passage 54 and reaches the gap between the bush 53 and the accommodating recess 15, thereby suitably lubricating the gap between the second plain bearing 13 and the bush 53. In this respect as well, the durability of this compressor is high.

[0124] In addition, in this compressor, the first fluid passage 3 functions as an oil reservoir for the lubricating oil 18, so there is no need to form a dedicated oil reservoir within the housing 6. Furthermore, in this compressor, the second fluid passage 7 and the communication passage 9 are formed in the second diameter portion 64b, so that the second fluid passage 7 and the communication passage 9 can be easily formed.

[0125] Here, the second diameter portion 64b has a flange portion 642, which is formed with a larger diameter than the main body portion 641. The communication passage 9 is formed in the flange portion 642 and opens to the outer peripheral surface of the flange portion 642. Therefore, the communication passage 9 communicates with the scroll chamber 65 at a position close to the lower part of the scroll chamber 65, making it easier for the lubricating oil 18 in the scroll chamber 65 to flow suitably through the communication passage 9. As a result, in this compressor, the lubricating oil 18 in the scroll chamber 65 can be suitably sucked into the compression chamber 12.

[0126] In addition, in this compressor, the housing body 60 and the protruding body 64 are formed as separate bodies. Therefore, in this compressor, by making the housing body 60 from an aluminum alloy and the protruding body 64 from steel, it is possible to suitably ensure the rigidity and heat resistance of the protruding body 64.

[0127] Furthermore, since the housing main body 60 and the protrusion 64 are separate bodies, this compressor makes it easy to form the first fluid passage 3 for the second diameter portion 64b, and when the protrusion 64 is fixed to the housing main body 60, the rear end of the first fluid passage 3 can be suitably closed by the rear wall 60b of the housing main body 60.

[0128] 2 , the compressor of the second embodiment differs from the compressor of the first embodiment in that a protrusion 71 is provided on the housing body 60 instead of the protrusion 64. Also, in this compressor, unlike the compressor of the first embodiment, the driving scroll 30 has a cover body 75 instead of the cover body 37.

[0129] The protrusion 71 is also made of steel and has a first diameter portion 71a and a second diameter portion 71b. The first diameter portion 71a has a configuration similar to that of the first diameter portion 64a in the compressor of Example 1. As a result, the first diameter portion 71a also has a pin hole 4 and a first passage 5 formed therein. In addition, a first plain bearing 51 is also provided on the outer peripheral surface of the first diameter portion 71a.

[0130] The second diameter portion 71b is constituted by a main body portion 711 and a flange portion 712. The main body portion 711 and the flange portion 712 are formed to have the same dimensions as the main body portion 711 and the flange portion 712 in the compressor of the first embodiment, respectively.

[0131] The second diameter portion 71b is formed with a fluid passage 72 and a second passage 73. The fluid passage 72 has a configuration similar to that of the first fluid passage 3 in the compressor of the first embodiment, and is in communication with the pin hole 4 and the first passage 5, respectively.

[0132] The second passage 73 is formed in the main body portion 711. In this case, the second passage 73 is formed on the rear side of the main body portion 711, in the vicinity of the flange portion 712. The second passage 73 penetrates the main body portion 711 in the radial direction of the second diameter portion 71b. As a result, the second passage 73 communicates with the fluid passage 72 and opens to the outer circumferential surface of the main body portion 711.

[0133] Similar to the protrusion 64 in the compressor of the first embodiment, the protrusion 71 is fixed to the rear wall 60b by fitting the flange portion 712 into the mounting recess 60c, so that the rear end of the fluid passage 72 is closed by the rear wall 60b.

[0134] The cover body 75 is fixed to the drive peripheral wall 35 by the first bolts 34a, similar to the cover body 37 in the compressor of the first embodiment. The cover body 75 is composed of a cover main body portion 75a and an extension portion 75b. Similar to the cover main body portion 37a in the compressor of the first embodiment, the cover main body portion 75a is formed with a recess 37c, an insertion hole 37d, a return passage 37f, and a first bolt hole 37g. The extension portion 75b has the same configuration as the extension portion 37b in the compressor of the first embodiment and is formed integrally with the cover main body portion 75a.

[0135] Furthermore, in the cover body 75, an inlet passage 75c is formed in the cover main body 75a. The inlet passage 75c is also an example of a "supply passage" according to the present invention. The inlet passage 75c penetrates the cover main body 75a in the direction of the drive axis O1. As a result, the front end of the inlet passage 75c opens to a second front surface 751 of the cover main body 75a and communicates with the inlet section 30a. Meanwhile, the rear end of the inlet passage 75c opens to a second rear surface 752 of the cover main body 75a. In this case, the rear end of the inlet passage 75c opens to the second rear surface 752 at a location radially outward of the cover body 75 relative to the extension portion 75b. Thus, the rear end of the inlet passage 75c communicates with the scroll chamber 65.

[0136] In this compressor, the rotor 11 is fixed to the outer peripheral surface of the extension portion 75b. The first diameter portion 71a and the main body portion 711 of the second diameter portion 71b of the protrusion 71 are inserted into the extension portion 75b. As a result, a gap S is formed between the inner peripheral surface of the extension portion 75b and the main body portion 711, similar to the compressor of the first embodiment.

[0137] In this compressor, the first plain bearing 51 is also inserted into the insertion hole 37d. As a result, the cover body 75 is rotatably supported on the first diameter portion 71a via the first plain bearing 51. The fluid passage 72 and the recess 37c, and therefore the fluid passage 72 and the return passage 37f, are connected via the pin hole 4 and the first passage 5, respectively.

[0138] Furthermore, in this compressor, with the cover body 75 rotatably supported on the first diameter portion 71a, the second passage 73 is located rearward of the extension portion 75b. As a result, the second passage 73 faces the scroll chamber 65 rearward of the gap S and communicates with the scroll chamber 65. As a result, the second passage 73 communicates with the suction passage 75c through the scroll chamber 65. The other configurations of this compressor are similar to those of the compressor of the first embodiment, and the same components are designated by the same reference numerals, and detailed description of the configurations will be omitted.

[0139] In this compressor, similarly to the compressor of the first embodiment, the lubricating oil 18 discharged into the discharge chamber 14 flows through the return passage 37f and the like (see the solid arrow in FIG. 2 ). As a result, in this compressor, the lubricating oil 18 discharged into the discharge chamber 14 flows into the fluid passage 72 and is stored in the fluid passage 72. In this compressor, the fluid passage 72 also functions as a reservoir for the lubricating oil 18. The lubricating oil 18 in the fluid passage 72 flows through the second passage 73 and then flows into the scroll chamber 65.

[0140] 2, in this compressor, the refrigerant in the scroll chamber 65 flows between the stator 17 and the rotor 11 and reaches the suction passage 75c. Therefore, in this compressor, the refrigerant can suitably cool the electric motor 10. Furthermore, when the refrigerant flows between the stator 17 and the rotor 11, the lubricating oil 18 that has flowed into the scroll chamber 65 from the second passage 73 also flows between the stator 17 and the rotor 11 together with the refrigerant and reaches the suction passage 75c. In this manner, in this compressor, the refrigerant and the lubricating oil 18 flow through the suction passage 75c and are drawn into the compression chamber 12 from the suction section 30a.

[0141] In this manner, in this compressor, the lubricating oil 18 can suitably lubricate the driving scroll 30 and the driven scroll 40, including the inside of the compression chamber 12. Furthermore, since the lubricating oil in the scroll chamber 65 flows between the stator 17 and the rotor 11 together with the refrigerant and reaches the suction passage 75c, in this compressor, the lubricating oil 18 can suitably lubricate the electric motor 10.

[0142] Furthermore, in this compressor, unlike the compressor of Example 1, the second fluid passage 7 and the communication passage 9 are not formed in the second diameter portion 71b. Therefore, in this compressor, it is easy to form the protrusion 71, including the second diameter portion 71b. Other functions of this compressor are the same as those of the compressor of Example 1.

[0143] As shown in Fig. 3, the compressor of the third embodiment differs from the compressor of the first embodiment in that the housing 6 has a housing body 61 instead of the housing body 60. Also, in this compressor, unlike the compressor of the first embodiment, the driving scroll 30 has a cover body 77 instead of the cover body 37.

[0144] The housing body 61 is made of an aluminum alloy. The housing body 61 is a bottomed, cylindrical member having an outer peripheral wall 61a and a rear wall 61b. The outer peripheral wall 61a is cylindrical and has a drive shaft center O1 as its center. As with the compressor of the first embodiment, a housing cover 62 is fixed to the housing body 61. This forms a scroll chamber 65 within the housing body 61.

[0145] The rear wall 61b is located at the rear end of the housing main body 61. The rear wall 61b extends in a generally circular, flat plate shape perpendicular to the drive axis O1. The outer peripheral edge of the rear wall 61b is connected to the rear end of the outer peripheral wall 61a. The rear wall 61b also has a mounting recess 61c. The mounting recess 61c is recessed from the front to the rear on the inner surface of the rear wall 61b.

[0146] Furthermore, a connection passage 81 is formed in the rear wall 61b. The connection passage 81 is composed of a first connection passage 81a and a second connection passage 81b. The first connection passage 81a extends radially inside the rear wall 61b of the housing main body 61 and opens onto the outer circumferential surface of the rear wall 61b. The portion of the first connection passage 81a that opens onto the outer circumferential surface of the rear wall 61b is an intake communication port 810, which is connected to an evaporator (not shown) via piping (not shown).

[0147] The second connection passage 81b is disposed forward of the first connection passage 81a in the rear wall 61b and penetrates the rear wall 61b in the direction of the drive axis O1. As a result, the rear end of the second connection passage 81b is connected to the first connection passage 81a. Meanwhile, the front end of the second connection passage 81b opens into the mounting recess 61c.

[0148] A protrusion 79 is provided inside the housing main body 61. The protrusion 79 is made of steel. The protrusion 79 has a first diameter portion 79a and a second diameter portion 79b. The first diameter portion 79a forms the front portion of the protrusion 79 and is formed in a generally cylindrical shape having the same size as the first diameter portion 64a in the compressor of the first embodiment. A pin hole 4a is formed in the first diameter portion 64a. The pin hole 4a is recessed rearward from the front end surface of the first diameter portion 79a. Therefore, the pin hole 4a does not penetrate the first diameter portion 79a in the direction of the drive axis O1. A first plain bearing 51 is also provided on the outer circumferential surface of the first diameter portion 79a.

[0149] The second diameter portion 79b is located rearward of the first diameter portion 79a and constitutes the rear portion of the protrusion 79. The second diameter portion 79b is formed to have a larger diameter than the first diameter portion 79a. The second diameter portion 79b is composed of a main body portion 791 and a flange portion 792. The main body portion 791 constitutes the front portion of the second diameter portion 79b, and the flange portion 792 constitutes the rear portion of the second diameter portion 79b.

[0150] The main body portion 791 is formed to have the same size as the main body portion 641 in the compressor of Example 1, and is connected to the first diameter portion 79a. The flange portion 792 is formed to have a larger diameter than the main body portion 791. Here, the flange portion 792 is formed to have a smaller diameter than the flange portion 642 in the compressor of Example 1. Note that the flange portion 792 may be formed to have the same size as the flange portion 642.

[0151] The second diameter portion 79b is formed with a fluid passage 83 and a first refrigerant passage 85. The fluid passage 83 has a diameter larger than that of the pin hole 4a, extends inside the main body portion 791 and the flange portion 792 in the direction of the drive axis O1, and opens at the rear end surface of the flange portion 792. The fluid passage 83 is not in communication with the pin hole 4a.

[0152] The first refrigerant passage 85 is formed in the main body portion 791 and penetrates the main body portion 791 in the radial direction of the second diameter portion 79b. As a result, the first refrigerant passage 85 communicates with the fluid passage 83 and opens to the outer circumferential surface of the main body portion 791.

[0153] The protrusion 79 is fixed to the rear wall 61b by fitting the flange portion 792 into the mounting recess 61c. As a result, the rear end of the fluid passage 83 communicates with the second connection passage 81b. Thus, the fluid passage 83 communicates with the first connection passage 81a through the second connection passage 81b. The rear end of the fluid passage 83 is closed by the rear wall 61b except for the portion communicating with the second connection passage 81b.

[0154] The cover body 77 is fixed to the drive peripheral wall 35 by the first bolts 34a, similar to the cover body 37 in the compressor of the first embodiment. The cover body 77 is composed of a cover main body portion 77a and an extension portion 77b. Similar to the cover main body portion 37a in the compressor of the first embodiment, the cover main body portion 77a is formed with a recess 37c, an insertion hole 37d, a return passage 37f, and a first bolt hole 37g. The extension portion 77b has the same configuration as the extension portion 37b in the compressor of the first embodiment and is formed integrally with the cover main body portion 77a.

[0155] Furthermore, a second refrigerant passage 77c is formed in the cover main body 77a of the cover body 77. The second refrigerant passage 77c penetrates the cover main body 77a in the front-to-rear direction, with its front end opening to a second front surface 771 of the cover main body 77a and its rear end opening to a second rear surface 772 of the cover main body 77a. The second refrigerant passage 77c is inclined radially inward of the cover body 77 from the front to the rear. As a result, the rear end of the second refrigerant passage 77c opens to the second rear surface 772 at a location radially inward of the cover body 77 relative to the extension portion 77b.

[0156] In addition, in this compressor, a bush passage 54 is not formed for the bush 53. A driven pin 56 is inserted through the bush 53. The driven pin 56 is formed in the shape of a solid shaft.

[0157] In this compressor, the rotor 11 is fixed to the outer peripheral surface of the extension portion 77b. Furthermore, the first diameter portion 79a of the protrusion 79 and the main body portion 791 of the second diameter portion 79b are inserted into the extension portion 77b. As a result, in this compressor as well, a gap S is formed between the inner peripheral surface of the extension portion 77b and the main body portion 791. As a result, the rear end of the second refrigerant passage 77c communicates with the gap S, and the suction section 30a and the scroll chamber 65 communicate with each other through the second refrigerant passage 77c.

[0158] Furthermore, by inserting the main body portion 791 into the extension portion 77 b, the first refrigerant passage 85 is positioned inside the extension portion 77 b. As a result, the fluid passage 83 communicates with the gap S through the first refrigerant passage 85.

[0159] In this compressor, too, the first plain bearing 51 is inserted into the insertion hole 37d. As a result, the cover body 77 is rotatably supported on the first diameter portion 79a via the first plain bearing 51. Furthermore, the driven pin 56 is inserted into the pin hole 4a, so that the driven scroll 40 is rotatably supported around the driven axis O2 relative to the first diameter portion 79a. The other configurations of this compressor are similar to those of the compressor of the first embodiment.

[0160] This compressor is mounted on the vehicle with the suction communication port 810 facing upward of the compressor. Therefore, in this compressor, the first connection passage 81 a opens into the housing main body 61 at a position higher in the direction of gravity than the fluid passage 83.

[0161] 3, low-temperature, low-pressure refrigerant that has passed through the evaporator is drawn into the suction port 810, i.e., the first connection passage 81a, as suction refrigerant. The suction refrigerant in the first connection passage 81a flows into the fluid passage 83 via the second connection passage 81b. As a result, the suction refrigerant is separated into gas refrigerant, which is a gas phase refrigerant, and liquid refrigerant 88, which is a liquid phase refrigerant, in the fluid passage 83. That is, in this compressor, the fluid passage 83 functions as a gas-liquid separation chamber for the suction refrigerant.

[0162] Thus, liquid refrigerant 88 is stored in the fluid passage 83. Meanwhile, gaseous refrigerant flows from the fluid passage 83 through the first refrigerant passage 85 and the gap S to the second refrigerant passage 77c. As a result, the gaseous refrigerant flows through the second refrigerant passage 77c and is drawn into the compression chambers 12 from the suction section 30a. Strictly speaking, the suctioned refrigerant drawn into the first connecting passage 81a also contains lubricating oil 18. Therefore, the lubricating oil 18 contained in the suctioned refrigerant flows together with the gaseous refrigerant from the first refrigerant passage 85 through the gap S to the second refrigerant passage 77c, and then flows through the second refrigerant passage 77c to be drawn into the compression chambers 12. Furthermore, some of the lubricating oil 18 contained in the suctioned refrigerant is stored in the fluid passage 83 together with the liquid refrigerant 88.

[0163] 3, in this compressor, the lubricating oil 18 in the discharge chamber 14 flows through the return passage 37f and reaches the recess 37c. As a result, in this compressor, the bushing 53 and other components are lubricated by the lubricating oil 18 in the recess 37c. The lubricating oil 18 in the recess 37c flows through the gap between the cover body 77 and the driven end plate 41 and is drawn into the compression chamber 12 from the suction port 30a together with the gaseous refrigerant. In this compressor, the driving scroll 30 and the driven scroll 40 are lubricated by the lubricating oil 18.

[0164] In this way, in this compressor, by using the inside of the fluid passage 83 as a gas-liquid separation chamber, there is no need to provide a separate space dedicated to this purpose within the housing 6. Furthermore, the intake refrigerant that flows from the connecting path 81 into the fluid passage 83 has a lower temperature and pressure than the refrigerant discharged from the compression chamber 12 to the discharge chamber 14. For this reason, in this compressor, the protruding body 79 is unlikely to reach a high temperature due to the intake refrigerant that flows through the fluid passage 83, including the liquid refrigerant 88, and therefore the first sliding bearing 51 is unlikely to reach a high temperature. Furthermore, in this compressor, because the liquid refrigerant 88 is stored in the fluid passage 83, it is possible to effectively prevent the liquid refrigerant 88 from being drawn into the compression chamber 12.

[0165] Furthermore, in this compression, the suction communication port 810 opens into the housing body 61 at a location higher in the direction of gravity than the fluid passage 83, so the first connecting passage 81a, including the suction communication port 810, is located higher in the direction of gravity than the fluid passage 83. This effectively prevents the liquid refrigerant 88 in the fluid passage 83 from flowing back through the connecting passage 81 and out of the compressor through the suction communication port 810. Other operations of this compressor are similar to those of the compressor of the first embodiment.

[0166] As shown in Fig. 4, the compressor of the fourth embodiment includes an electric motor 10a instead of the electric motor 10 in the compressor of the first embodiment. The electric motor 10a is also an example of the "drive mechanism" of the present invention. Also, unlike the compressor of the first embodiment, the drive scroll 30 of this compressor includes a cover body 90 instead of the cover body 37.

[0167] The electric motor 10a is housed in the scroll chamber 65. The electric motor 10a is composed of a stator 16 and a rotor 19. The stator 16 is cylindrical and has a drive shaft center O1, and has windings 16a. The stator 16 has a smaller diameter than the stator 17 in the compressor of the first embodiment. The stator 16 is fixed to the second diameter portion 64b by fitting onto the outer peripheral surface of the main body portion 641 of the second diameter portion 64b.

[0168] The rotor 19 is cylindrical and surrounds the drive axis O1. The rotor 19 has a larger diameter than the stator 16 and is formed to have approximately the same diameter as the cover body 90. The rotor 19 is disposed in the scroll chamber 65, thereby covering the stator 17 from the outside. The rotor 19 also has a plurality of third bolt holes 19a formed therein. Each of the third bolt holes 19a penetrates the rotor 19 in the direction of the drive axis O1.

[0169] The cover body 90 is composed of a cover main body portion 90a and a wall portion 90b. The cover main body portion 90a extends in a generally disk-like shape perpendicular to the drive axis O1 and the driven axis O2, and 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 90a has a second front surface 901 facing forward and a second rear surface 902 facing rearward and located on the opposite side of the second front surface 901. The cover main body portion 90a is formed with a recess 37c, an insertion hole 37d, and a return passage 37f, similar to the cover main body portion 37a in the compressor of the first embodiment.

[0170] The wall portion 90b is formed in a cylindrical shape having the same diameter as the cover main body portion 90a. The wall portion 90b is formed integrally with the cover main body portion 90a and extends rearward from the second rear surface 902 in the direction of the drive axis O1.

[0171] The cover body 90 also has an intake passage 90c and a plurality of fourth bolt holes 90d. The intake passage 90c is an example of a "supply passage" according to the present invention. The intake passage 90c is formed in the cover main body 90a and penetrates the cover main body 90a in the direction of the drive axis O1. As a result, the front end of the intake passage 90c opens to the second front surface 901, and the rear end of the intake passage 90c opens to the second rear surface 902. Here, the rear end of the intake passage 90c opens to the second rear surface 902 at a location radially inward of the cover body 90 from the wall portion 90b.

[0172] Each fourth bolt hole 90d is formed across the cover body 90a and the wall 90b, penetrating the cover body 90a and the wall 90b in the direction of the drive axis O1. Note that Fig. 4 illustrates only one of the multiple fourth bolt holes 90d. The same applies to the third bolt holes 19a.

[0173] In this compressor, a cover body 90 is disposed between the drive circumferential wall 35 and the rotor 19, and third bolts 91 are inserted through the third and fourth bolt holes 19a, 90d to secure the drive circumferential wall 35, cover body 90, and rotor 19 together. As a result, in this compressor, the drive scroll 30 can rotate about the drive axis O1 when the rotor 19 rotates. In addition, in this compressor, the scroll chamber 65 and the suction section 30a are connected by a suction passage 90c. The remaining configuration of this compressor is the same as that of the compressor of the first embodiment.

[0174] In this compressor, the refrigerant in the scroll chamber 65 flows between the stator 16 and the rotor 19 and reaches the suction passage 90c. Therefore, in this compressor, the refrigerant can suitably cool the electric motor 10a.

[0175] Furthermore, in this compressor, the lubricating oil 18 that has flowed through the second fluid passage 7 and the second passage 8 also flows inside the wall portion 90b and reaches the suction passage 90c. The refrigerant and lubricating oil 18 flow through the suction passage 90c and are drawn into the compression chamber 12 from the suction portion 30a. In this way, the suction passage 90c not only draws the refrigerant into the compression chamber 12, but also functions as a supply passage that supplies the lubricating oil 18 to the compression chamber 12. In this way, this compressor can achieve the same functions as the compressor of the first embodiment.

[0176] Although the present invention has been described above in accordance with Examples 1 to 4, it goes without saying that the present invention is not limited to the above Examples 1 to 4, and can be appropriately modified and applied within the scope of the invention.

[0177] For example, a compressor may be formed by appropriately combining the configurations of the compressors of the first to fourth embodiments.

[0178] In the compressors of the first and fourth embodiments, the second fluid passage 7 and the communication passage 9 may be omitted.

[0179] In the compressor of Example 1, the first diameter portion 64a of the protrusion 64 may be made of steel, while the second diameter portion 64b may be made of an aluminum alloy. The material of the protrusion 64, including the first diameter portion 64a, can be designed appropriately as long as it has enough strength to support the cover body 37. The same applies to the compressors of Examples 2 to 4.

[0180] In addition, in the compressor of the first embodiment, the driving scroll 30 has the cover body 37, but this is not limiting, and the driven scroll 40 may have the cover body 37. The same applies to the compressors of the second to fourth embodiments.

[0181] In addition, in the compressor of Example 1, the housing main body 60 and the protruding body 64 are formed as separate bodies, but this is not limiting, and the protruding body 64 may be formed integrally with the housing main body 60. The same applies to the compressors of Examples 2 to 4.

[0182] In the compressor of the third embodiment, a plate or the like may be provided in the fluid passage 83 to promote gas-liquid separation of the suctioned refrigerant.

[0183] The present specification also includes the following inventions: (Supplementary Note 1) A double rotary scroll compressor comprising a housing, a drive mechanism, a driving scroll, a driven scroll, a driven mechanism, and a discharge region, 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 a fluid by the rotational driving and the rotational driven, and the discharge region discharges the fluid compressed in the compression chamber, wherein the housing is provided with a protrusion 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 or the driven scroll has a cover body rotatably supported on the first diameter portion via a bearing, The scroll compressor according to claim 1, wherein the second diameter portion is fixed to the housing, and ... (Supplementary Note 3) A double-rotary scroll compressor according to Supplementary Note 1 or 2, wherein the specific fluid is a lubricating oil contained in the fluid, the fluid passage is capable of storing the lubricating oil while circulating it, the protruding body is formed with a first passage connected to the fluid passage and circulating the lubricating oil through the fluid passage, and a second passage connected to the fluid passage at a position different from the first passage and circulating the lubricating oil in the fluid passage toward the outside of the fluid passage, and the cover body is formed with a return passage communicating with the discharge region and the first passage and circulating the lubricating oil from the discharge region toward the first passage, and a supply passage communicating with the second passage and the compression chamber and circulating the lubricating oil from the second passage toward the compression chamber.(Appendix 4) A double-rotary scroll compressor according to appendix 3, wherein the drive scroll has the cover body, the driven scroll is formed with an accommodating recess facing the first diameter portion in the drive shaft center direction, a bush is accommodated in the accommodating recess, the bush is provided with a shaft body extending in the drive shaft center direction and inserted into the first diameter portion, and a bushing passage is formed to circulate the lubricating oil from the return passage toward the first passage into the accommodating recess, and an axial hole is formed inside the shaft body, extending in the drive shaft center direction and communicating with the accommodating recess and the fluid passage, and circulating the lubricating oil from the accommodating recess toward the fluid passage. (Appendix 5) A double-rotary scroll compressor according to appendix 1 or 2, wherein the housing is formed with an intake communication port for sucking fluid into the scroll chamber from outside the housing, the specific fluid is lubricating oil contained in the fluid, the second diameter portion is formed with a communication passage that is connected to the fluid passage and communicates with a location in the scroll chamber that is lower in the direction of gravity than the second diameter portion, and that circulates the lubricating oil in the scroll chamber toward the fluid passage, and the cover body is formed with an intake passage that is communicated with the fluid passage and the compression chamber, and that circulates the lubricating oil that has circulated through the fluid passage toward the compression chamber. (Appendix 6) The cover body has an extension portion formed thereon that is cylindrical and extends in the direction of the drive shaft center and that covers the second diameter portion from the outside, and a gap is provided between the extension portion and the second diameter portion that communicates with the scroll chamber and allows fluid within the scroll chamber to flow, and the suction passage causes the fluid that has flowed through the gap to flow toward the compression chamber together with the lubricating oil.(Supplementary Note 7) A double-rotating scroll compressor according to Supplementary Note 1 or 2, wherein a connection passage is formed in the housing, connecting the fluid passage to the outside of the housing, the specific fluid is an intake refrigerant drawn into the fluid passage by the connection passage, the fluid passage separates the intake refrigerant into a gas phase refrigerant and a liquid phase refrigerant, and is capable of storing the liquid refrigerant, the connection passage opens into the housing at a location above the fluid passage in the direction of gravity, the second diameter portion is formed with a first refrigerant passage that circulates the gas refrigerant in the fluid passage into the scroll chamber, and the cover body is formed with a second refrigerant passage that communicates with the scroll chamber and the compression chamber, and circulates the gas refrigerant in the scroll chamber toward the compression chamber. (Supplementary Note 8) The double-rotating scroll compressor according to any one of Supplementary Notes 1 to 7, wherein the driving scroll has the cover body, the cover body has a cylindrical shape extending in the drive shaft direction and is formed with an extension portion covering the second diameter portion from the outside, and the driving mechanism has a stator fixed to the housing and disposed within the scroll chamber, and a rotor fixed to the extension portion and disposed within the stator. (Supplementary Note 9) The double-rotating scroll compressor according to any one of Supplementary Notes 1 to 7, wherein the driving scroll has the cover body, and the driving mechanism has a stator fixed to the second diameter portion and disposed within the scroll chamber, and a rotor fixed to the cover body and covering the stator from the outside within the scroll chamber.

[0184] The present invention can be used in vehicle air conditioning systems and the like.

[0185] 3 First fluid passage (fluid passage) 5 First passage 6 Housing 7 Second fluid passage (fluid passage) 8 Second passage 10, 10a Electric motor (drive mechanism) 11, 19 Rotor 12 Compression chamber 14 Discharge chamber (discharge area) 15 Accommodating recess 16, 17 Stator 18 Lubricating oil (specific fluid) 20 Follower mechanism 30 Driving scroll 37, 75, 77, 90 Cover body 37b, 77b Extension portion 37e, 75c, 90c Suction passage (supply passage) 37f Return passage 40 Follower scroll 51 First plain bearing (bearing) 53 Bush 54 Bush passage 55 Follower pin (shaft body) 55a Shaft hole 64, 71, 79 Protrusion 64a, 71a, 79a First diameter portion 64b, 71b, 79b Second diameter portion 65 Scroll chamber 68 Suction communication port 72, 83 Fluid passage 77c Second refrigerant passage 81 Connection passage 85 First refrigerant passage 88 Liquid refrigerant O1 Drive shaft center O2 Driven shaft center S Clearance

Claims

1. A double rotary scroll compressor comprising a housing, a drive mechanism, a driving scroll, a driven scroll, a driven mechanism, and a discharge region, 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 compression chambers that compress a fluid by the rotational driving and the rotational driven, and the discharge region discharges the fluid compressed in the compression chamber, wherein the housing is provided with a protrusion 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 that is larger in diameter than the first diameter portion, and the driving scroll or the driven scroll has a cover body that is rotatably supported on the first diameter portion via a bearing, a fluid passage formed inside the second diameter portion, the fluid passage communicating with the outside of the second diameter portion and through which a specific fluid having a lower temperature and pressure than the fluid in the discharge region can flow; 2. A double-rotating scroll compressor according to claim 1, wherein the housing and the protrusion are formed as separate bodies, and the second diameter portion is fixed to the housing.

3. A double rotary scroll compressor according to claim 1 or 2, wherein the specific fluid is a lubricating oil contained in the fluid, the fluid passage is capable of storing the lubricating oil while allowing it to circulate, the protrusion is formed with a first passage connected to the fluid passage and allowing the lubricating oil to circulate through the fluid passage, and a second passage connected to the fluid passage at a position different from the first passage and allowing the lubricating oil in the fluid passage to circulate toward the outside of the fluid passage, and the cover is formed with a return passage communicating with the discharge area and the first passage and allowing the lubricating oil to circulate from the discharge area toward the first passage, and a supply passage communicating with the second passage and the compression chamber and allowing the lubricating oil to circulate from the second passage toward the compression chamber.

4. A double-rotating scroll compressor as claimed in claim 3, wherein the drive scroll has the cover body, the driven scroll is formed with a accommodating recess facing the first diameter portion in the direction of the drive shaft center, a bush is accommodated in the accommodating recess, the bush is provided with a shaft body extending in the direction of the drive shaft center and inserted into the first diameter portion, and a bushing passage is formed in the bush to circulate the lubricating oil from the return passage toward the first passage into the accommodating recess, and an axial hole is formed inside the shaft body extending in the direction of the drive shaft center and communicating with the accommodating recess and the fluid passage, and to circulate the lubricating oil from the accommodating recess toward the fluid passage.

5. A double rotary scroll compressor according to claim 1 or 2, wherein the housing is formed with an intake communication port for drawing fluid into the scroll chamber from outside the housing, the specific fluid being lubricating oil contained in the fluid, the second diameter portion is formed with a communication passage that is connected to the fluid passage and communicates with a location in the scroll chamber that is lower in the direction of gravity than the second diameter portion, and that circulates the lubricating oil in the scroll chamber toward the fluid passage, and the cover body is formed with an intake passage that is communicated with the fluid passage and the compression chamber, and that circulates the lubricating oil that has circulated through the fluid passage toward the compression chamber.

6. A double-rotating scroll compressor as claimed in claim 5, wherein the cover body has an extension portion formed thereon that is cylindrical and extends in the direction of the drive shaft center and that covers the second diameter portion from the outside, and between the extension portion and the second diameter portion there is provided a gap that communicates with the scroll chamber and allows fluid within the scroll chamber to flow, and the suction passage allows the fluid that has flowed through the gap to flow towards the compression chamber together with the lubricating oil.

7. A double-rotating scroll compressor according to claim 1 or 2, wherein a connecting passage is formed in the housing, connecting the fluid passage to the outside of the housing, the specific fluid is an intake refrigerant drawn into the fluid passage by the connecting passage, the fluid passage separates the intake refrigerant into a gas phase refrigerant and a liquid phase refrigerant, and is capable of storing the liquid refrigerant, the connecting passage opens into the housing at a location above the fluid passage in the direction of gravity, the second diameter portion is formed with a first refrigerant passage that circulates the gas refrigerant in the fluid passage into the scroll chamber, and the cover body is formed with a second refrigerant passage that communicates with the scroll chamber and the compression chamber, and circulates the gas refrigerant in the scroll chamber toward the compression chamber.

8. A double-rotating scroll compressor according to claim 1 or 2, wherein the drive scroll has the cover body, the cover body has a cylindrical extension extending in the direction of the drive axis and covering the second diameter portion from the outside, and the drive mechanism has a stator fixed to the housing and arranged within the scroll chamber, and a rotor fixed to the extension and arranged within the stator.

9. A double-rotating scroll compressor according to claim 1 or 2, wherein the drive scroll has the cover body, and the drive mechanism has a stator fixed to the second diameter portion and arranged within the scroll chamber, and a rotor fixed to the cover body while covering the stator from the outside within the scroll chamber.

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