Scroll compressor

Abstract

This scroll compressor comprises a housing (6), a drive mechanism (10), a first screw (30), and a second screw (40). The first screw (30) and the second screw (40) form a compression chamber (12) for compressing a refrigerant. A housing component (15) is fixed to the first screw (30). A discharge chamber (16) is formed within the housing component (15). The discharge chamber (16) is connected to the compression chamber (12), and the refrigerant that has been compressed in the compression chamber (12) is discharged into it. The housing component (15) is supported by the housing (6) via a bearing (14) to allow it to rotate within the housing (6). The discharge chamber (16) has a larger diameter than the outer diameter of the bearing (14).

Description

TECHNICAL AREA

[0001] The present invention relates to a scroll compressor. TECHNICAL BACKGROUND

[0002] Patent literature 1 discloses a conventional scroll compressor (hereinafter simply referred to as a compressor). The compressor has a housing, a drive mechanism, a first screw, a second screw, and an output mechanism. The drive mechanism and the first screw are housed in the housing. The housing is provided with a hub that projects towards the first screw. A support hole is formed inside the hub.

[0003] The first worm gear has a drive shaft. The drive shaft is cylindrical and houses the hub. A bearing is located between the drive shaft and the hub, specifically between the inner circumferential surface of the drive shaft and the outer circumferential surface of the hub. The outer circumferential surface of the drive shaft is fixed to the drive mechanism. In this way, the first worm gear is fixed to the drive mechanism within the housing and supported by the hub via the bearing, allowing it to rotate around a drive axis.

[0004] The second screw is housed inside the first screw. The second screw thus forms a compression chamber with the first screw. The second screw is equipped with an output shaft that projects towards the hub. The output shaft is inserted into the support hole. Consequently, the second screw, housed inside the first screw, is rotatably supported by the hub around an output axis. A discharge chamber is formed inside the output shaft. The discharge chamber is connected to the compression chamber. The output mechanism is located between the first and second screws.

[0005] In this compressor, the first screw is driven around the drive axis by the drive mechanism, and the output screw follows, rotating around the output axis, driven by the first screw and the output mechanism. As a result, the volume of the compression chamber is changed by the rotating first screw and the rotating second screw. In this way, the compressor compresses a refrigerant in the compression chamber while the refrigerant is drawn into the chamber. The compressed refrigerant is then discharged to the discharge chamber. Citation list patent literature

[0006] Patent literature 1: Japanese patent application publication no. H02-227575 SUMMARY OF THE INVENTION Technical Problem

[0007] This type of compressor requires very low noise levels during operation. However, in the conventional compressor, because the discharge chamber is located inside the output shaft of the second screw, the volume of the discharge chamber cannot be adequately guaranteed. Consequently, it is not possible to sufficiently reduce discharge pulsation when the refrigerant is transferred from the compression chamber to the discharge chamber, and it is difficult to improve noise levels.

[0008] Therefore, in this compressor, it is conceivable to increase the diameter of the discharge chamber to ensure sufficient volume. However, in this case, it is necessary to increase the diameter of the output shaft as well. Furthermore, in this compressor, it is necessary to increase the diameter of the hub's support hole, and consequently the hub diameter, in proportion to the increased output shaft diameter. Additionally, the diameters of the bearing and the output shaft of the first screw must be increased by increasing the hub diameter. However, if the bearing diameter is increased, it may not be able to adequately support the drive shaft during high-speed rotation of the first screw. Therefore, the compressor's reliability will be compromised.

[0009] The present invention has been made in view of the aforementioned conventional circumstances, and it is an object of the present invention to provide a scroll compressor which exhibits low noise levels and excellent durability. Solution to the problem

[0010] A scroll compressor according to the present invention comprises a housing, a drive mechanism, a first screw, and a second screw. The drive mechanism, the first screw, and the second screw are housed within the housing. A compression chamber, which compresses a refrigerant, is formed by the first screw and the second screw. A housing unit or housing component is fixed to at least one of the components—the first screw, the second screw, and the drive mechanism. The housing component includes a discharge chamber that is connected to the compression chamber and from which a refrigerant, compressed in the compression chamber, is discharged. The housing component is rotatably supported within the housing by a bearing, and the discharge chamber is configured to have a diameter larger than the outer diameter of the bearing.

[0011] In the scroll compressor of the present invention, the housing component is fixed to the first screw, the second screw, or the drive mechanism. The housing component is supported by the housing via the bearing and is rotatable within the housing. The discharge chamber is formed inside the housing component. Here, the discharge chamber is designed to have a diameter larger than the outer diameter of the bearing. As a consequence, since the volume of the discharge chamber can be adequately ensured in this compressor, the discharge pulsation when the refrigerant is discharged from the compression chamber to the discharge chamber can be suitably reduced.

[0012] Furthermore, in this compressor, because the outer diameter of the bearing is smaller than that of the discharge chamber, even if the diameter of the discharge chamber is increased, the bearing diameter does not need to increase. In other words, in this compressor, the bearing does not need to have the same diameter as the discharge chamber or a larger diameter. Consequently, even if the housing component rotates at high speed within the housing, the bearing can adequately support the housing component, the first screw attached to the housing component, and the like.

[0013] Therefore, the scroll compressor of the present invention exhibits a high degree of noise reduction and excellent reliability.

[0014] Lubricating oil can be dispensed to the discharge chamber along with the refrigerant, which is compressed in the compression chamber. Furthermore, the housing component can have a return flow path that returns the lubricating oil within the housing component to a section of the housing that has a lower pressure than the discharge chamber.

[0015] Since the housing component rotates within the housing, a centrifugal force exerted by the rotating housing component acts on the refrigerant, which is discharged into the discharge chamber. Thus, in the compressor of the present invention, the refrigerant and the lubricating oil can be suitably separated in the discharge chamber. Furthermore, since the housing component has the return flow path, the first screw, the second screw, and the like can be suitably lubricated in this compressor by the lubricating oil that is returned via the return flow path.

[0016] The first worm gear can be driven in a rotary motion around a drive axis by the drive mechanism. Furthermore, the second worm gear can follow the first worm gear in a rotary motion around the output axis by the output mechanism, while being eccentric with respect to the first worm gear. The housing component is preferably fixed to the first worm gear.

[0017] In this case, since the first screw is driven by rotation and the second screw follows in a rotating manner, the compressor of the present invention is a double rotary scroll compressor in which both the first screw and the second screw are rotated.

[0018] In this compressor, the housing component is fixed to the first screw, allowing the housing component and the discharge chamber to be positioned as close as possible to the compression chamber. Consequently, the refrigerant and the lubricating oil can be adequately separated from each other in the discharge chamber of this compressor.

[0019] In this case, the drive mechanism can have a stator fixed to the housing and a rotor in a tubular form that is rotatable within the stator. The housing component is preferably located inside the rotor.

[0020] By arranging the housing component inside the rotor, it is possible in this compressor to suppress an increase in the length of the housing in the drive axis direction, while increasing the volume of the housing component and the discharge chamber, compared to a design in which the housing component is located outside the rotor.

[0021] Furthermore, the first worm gear can be driven to rotate around a drive axis by the drive mechanism. The second worm gear can follow in rotation around an output axis via the first worm gear and the output mechanism, while being eccentric with respect to the first worm gear. The drive mechanism can also include a stator fixed in the housing and a rotor, which is tubular and rotatable within the stator. The first worm gear can also be located inside the rotor. The housing component is preferably fixed to the first worm gear.

[0022] In this case, since it is not necessary to position the housing component inside the rotor, the degree of design freedom regarding the shape of the housing component can be increased. As a result, it is easy to increase the diameter of the housing component, and thus it is easy to ensure a suitable volume for the discharge chamber in this compressor.

[0023] In the compressor of the present invention, the drive mechanism can comprise a stator fixed to the housing, a rotor in a tubular form rotatable within the stator, and a drive shaft fixed to the rotor and rotatable with it. The first screw can be fixed to the housing. The second screw can be connected to one end of the drive shaft and rotate relative to the first screw by the rotation of the drive shaft. The housing can be fixed to the other end of the drive shaft. It is preferred that a shaft path extending from one end to the other, connecting the compression chamber and the discharge chamber, is formed inside the drive shaft.

[0024] In this case, by fixing the housing component to the other end of the drive shaft, the housing component can be rotated within the housing by the rotation of the drive shaft. Furthermore, since the drive shaft has a shaft path, the refrigerant can flow appropriately from the compression chamber to the discharge chamber through the shaft path. Advantageous effects of the invention

[0025] The scroll compressor of the present invention exhibits low noise levels and excellent reliability. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a cross-sectional view of a scroll compressor according to a first embodiment. Fig. Figure 2 is a cross-sectional view of a scroll compressor according to a second embodiment. Fig. Figure 3 is a cross-sectional view of a scroll compressor according to a third embodiment. DESCRIPTION OF EXAMPLES OF EXECUTION

[0026] The first to third embodiments of the present invention are described below with reference to the drawings. The compressor of the first to third embodiments is mounted on a vehicle (not shown). (First embodiment)

[0027] As in Fig. As shown in Figure 1, the compressor according to the first embodiment is specifically a twin-rotary scroll compressor. The compressor has a housing 6, a drive mechanism 10, a drive screw 30, a discharge screw 40, a discharge mechanism 20, and a housing unit or housing component 15. The drive screw 30 is an example of a "first screw" in the present invention. The discharge screw 40 is an example of a "second screw" in the present invention.

[0028] In the present embodiment, the front-back direction of the compressor is defined by a continuous arrow pointing in Fig. Figure 1 illustrates this. It should be noted that the front-to-back direction is an example of a simplified description, and the compressor can appropriately change its position according to the vehicle on which it is mounted. The same applies to the compressors shown in Fig. 2 and Fig. 3 are shown.

[0029] As in Fig. As shown in Figure 1, the housing 6 has a housing body 60 and a housing cover 61. The housing body 60 and the housing cover 61 are made of an aluminum alloy.

[0030] The housing body 60 is a cylindrical component with a base, comprising an outer circumferential wall 60a and a rear wall 60b. The outer circumferential wall 60a is cylindrical with its center point on a drive axis O1. The drive axis O1 is parallel to the front-to-back direction. The outer circumferential wall 60a has an intake connection 69. The intake connection 69 extends through the outer circumferential wall 60a in the radial direction of the housing body 60. A pipe (not shown) is connected to the intake connection 69. Consequently, the intake connection 69 is connected to the outside of the housing 6, i.e., the outside of the compressor, through the pipe.

[0031] The rear wall 60b is located at the rear end of the housing body 60. The rear wall 60b extends in the form of an essentially circular flat plate perpendicular to the drive axis O1. The outer circumferential edge of the rear wall 60b is connected to the rear end of the outer circumferential wall 60a. The rear wall 60b has a first support section 64 at the center of its inner surface. The first support section 64 has an essentially column-like shape with its center on the drive axis O1 and projects forward from the center of the inner surface of the rear wall 60b, i.e., into a worm chamber 65, which will be described later. The rear wall 60b may have an intake connection port 69.

[0032] The first support section 64 has a pin hole 54. The pin hole 54 extends straight rearward within the first support section 64, while opening toward the front end face of the first support section 64. Here, the pin hole 54 does not pass through the first support section 64 in the front-to-back direction.

[0033] The housing cover 61 is arranged in front of the housing body 60. The housing cover 61 extends essentially in the form of a circular flat plate perpendicular to the drive axis O1. The housing cover 61 is fixed to the housing body 60 by a bolt (not shown) in such a way that its outer circumferential edge is in contact with the front end of the outer circumferential wall 60a of the housing body 60. Thus, the housing cover 61 closes the housing body 60 from the front. The worm chamber 65 is formed inside the housing body 60 in this manner.

[0034] A second support section 67 is formed at the center of the inner surface of the housing cover 61. The second support section 67 has a cylindrical shape with its center point on the drive axis O1 and projects rearward from the center of the inner surface of the housing cover 61.

[0035] The second support section 67 is provided with a radial ball bearing 14. The radial ball bearing 14 is an example of a "bearing" in the present invention. The length of the outer diameter of the radial ball bearing 14 is a first length L1 and is smaller than the second support section 67. The radial ball bearing 14 is fixed to the second support section 67 by fitting an outer ring into the second support section 67. A plain bearing or the like can be used as the "bearing" in the present invention.

[0036] The housing cover 61 has a discharge connection port 68. The discharge connection port 68 is located at the center of the housing cover 61 and extends through the housing cover 61 in the direction of the drive axis O1. The discharge connection port 68 faces a discharge passage 151, which will be described later, in the direction of the drive axis O1. A pipe (not shown) is connected to the discharge connection port 68. Therefore, the discharge connection port 68 is connected to the outside of the compressor through the pipe.

[0037] The screw chamber 65 is connected to the intake port 69. As a result, the low-pressure refrigerant is drawn into the screw chamber 65 from the outside of the compressor through the pipe connected to the intake port 69. Consequently, the screw chamber 65 also functions as a refrigerant intake chamber.

[0038] Specifically, the drive mechanism 10 is an electric motor and is housed in the worm gear chamber 65. Therefore, the worm gear chamber 65 also serves as a motor chamber, accommodating the drive mechanism 10. The drive mechanism 10 has a stator 17 and a rotor 11. The stator 17 has a stator core 17a and a coil end 17b. The stator core 17a has a cylindrical shape with its center point on the drive axis O1. The coil end 17b is formed by a portion of a coil wound around the stator core 17a and has an annular shape that projects from the stator core 17a in the direction of the drive axis O1. The stator 17 is fixed to the housing body 60 by fitting the stator core 17a into the inner circumferential surface of the outer circumferential wall 60a.

[0039] The rotor 11 has a cylindrical shape around the drive axis O1 and is arranged in the stator 17. Although not shown in detail, the rotor 11 has a plurality of permanent magnets corresponding to the stator 17, a plurality of electromagnetic steel plates for fixing the permanent magnets, and the like.

[0040] The drive screw 30 is made of an aluminum alloy. The drive screw 30 is housed in the screw chamber 65. The drive screw 30 has a drive end plate 31, a drive circumferential wall 32, a drive spiral body 33, and a cover body 35.

[0041] The drive end plate 31 extends essentially in a disc shape perpendicular to the drive axis O1 and a driven axis O2. Here, the driven axis O2 extends parallel to the drive axis O1, while being eccentric with respect to the drive axis O1. That is, the driven axis O2 is parallel to the front-to-back direction.

[0042] The drive end plate 31 has a front surface 311 facing the housing component 15 and a rear surface 312 located opposite the front surface 311. The drive end plate 31 has a discharge port 38. The discharge port 38 is located essentially in the center of the drive end plate 31 and extends through the drive end plate 31 in the direction of the drive axis O1.

[0043] Furthermore, a dispensing diaphragm valve 57 and a retainer 58 are fixed to the front surface 311 of the actuator end plate 31 by fixing bolts 59. As a result, the dispensing diaphragm valve 57 can open and close the dispensing port 38, and the retainer 58 can adjust the opening degree of the dispensing diaphragm valve 57.

[0044] The drive circumferential wall 32 is formed in a cylindrical shape that extends parallel to the drive axis O1 and the output axis O2, with a center point located on the drive axis O1. The drive circumferential wall 32 has a front end that is integrated with the outer circumferential edge of the drive end plate 31 and extends rearward from the drive end plate 31 in a cylindrical shape.

[0045] The drive spiral body 33 is arranged inside the drive circumferential wall 32. The drive spiral body 33 is integrated with the drive end plate 31 and extends rearward from the rear surface 312 of the drive end plate 31, i.e., parallel to the drive axis O1 and the output axis O2, toward the output screw 40. Although not shown in detail, the drive spiral body 33 extends in a spiral shape from the spiral center to the outer circumference, with the central face of the drive end plate 31 being defined as the spiral center. The outer circumferential end of the spiral of the drive spiral body 33 is connected to the inner circumferential surface of a drive circumferential wall 32.

[0046] The cover body 35 extends essentially in a disc shape perpendicular to the drive axis O1 and the output axis O2. The cover body 35 is designed to have essentially the same diameter as the drive end plate 31 and the drive circumferential wall 32. The cover body 35 has a front surface 351 and a rear surface 352. The front surface 351 faces the rear surface 312 of the drive end plate 31. The rear surface 352 is located opposite the front surface 351 and faces the rear wall 60b of the housing body 60.

[0047] The cover body 35 is provided with a hub 36 and an intake port 35a. The hub 36 is formed integrally at the center of the cover body 35 and projects rearward from the rear surface 352. An insertion hole 350 is formed in the hub 36. The insertion hole 350 extends through the interior of the hub 36 and the interior of the cover body 35 in the direction of the drive axis O1. As a result, the hub 36 has a cylindrical shape with its center point on the drive axis O1. A plain bearing 51 is provided in the insertion hole 350. Instead of the plain bearing 51, a ball bearing or the like may be provided in the insertion hole 350.

[0048] The intake port 35a is located outside the hub 36 in the radial direction of the cover body 35. The intake port 35a passes through the cover body 35 in the direction of the drive axis O1. Furthermore, the number of intake ports 35a, the position of the intake port 35a in the cover body 35, and the like can be designed appropriately.

[0049] A plurality of rings 22 are attached to a section of the cover body 35 between the hub 36 and the intake port 35a. The rings 22 are arranged at equal intervals around the circumference of the cover body 35, facing forward, and surround the hub 36 and the insertion hole 350 from the outside. In the present embodiment, the number of rings 22 is six. Fig. 1 also represents two of the six rings 22. The same applies to Fig. 2.

[0050] The drive screw 40, which is in Fig. The component shown in Figure 1 is made of an aluminum alloy. The output screw 40 is housed in the screw chamber 65, specifically in the drive screw 30. The output screw 40 has an output end plate 41 and an output spiral body 43.

[0051] The output end plate 41 extends essentially in a disc shape perpendicular to the drive axis O1 and the output axis O2. The output end plate 41 has a front surface 411 and a rear surface 412. The front surface 411 faces the rear surface 312 of the drive end plate 31 in the drive worm 30. The rear surface 412 is located opposite the front surface 411 and faces the front surface 351 of the cover body 35.

[0052] The output end plate 41 has a housing section 41a. The housing section 41a is recessed in a column-like shape with its center point on the output axis O2, projecting forward from the rear surface 412 of the output end plate 41. A bushing 53 is provided in the housing section 41a. The bushing 53 can be mounted in the housing section 41a via a sliding bearing, a ball bearing, or the like.

[0053] An output pin 55 is inserted through the bushing 53. At this point, the output pin 55 is inserted through the bushing 53 at its center, i.e., at a position eccentric to the output axis O2. The output pin 55 is made of steel and has a cylindrical shape. The output pin 55 projects rearward from the bushing 53 and thus from the output end plate 41.

[0054] Furthermore, a plurality of anti-rotation pins 21 are fixed on the outer circumferential side of the output end plate 41 relative to the housing section 41a and project rearward from the rear surface 412. Specifically, each anti-rotation pin 21 is fixed to a section that faces the ring 22 on the outer circumferential side relative to the housing section 41a. Thus, the anti-rotation pins 21 are arranged at equal intervals in the circumferential direction of the output end plate 41 and surround the housing section 41a and the bushing 53 from the outside. In the present embodiment, the number of anti-rotation pins 21 is six, corresponding to the number of rings 22. Fig. 1 and Fig. Figure 2 shows two of the six anti-rotation pins 21.

[0055] As in Fig. As shown in Figure 1, the output spiral body 43 is integrated with the output end plate 41 and extends forward from the front surface 411 of the output end plate 41, i.e., towards the input end plate 31, parallel to the input axis O1 and output axis O2. Although not shown in detail, the output spiral body 43 extends spirally from the spiral center to the outer circumference, with the central face of the output end plate 41 being defined as the spiral center.

[0056] The output mechanism 20 has the anti-rotation pins 21 and the rings 22. The number of each of the anti-rotation pins 21 and the number of rings 22 that form the output mechanism 20 can be changed in a suitable manner, as long as the number is three or more.

[0057] The housing component 15 is a cylindrical component with a base, comprising an outer circumferential wall 15a, a front wall 15b, and a flange wall 15c. The outer circumferential wall 15a has a cylindrical shape centered on the drive shaft O1. Here, the outer diameter of the outer circumferential wall 15a is larger than the outer diameter of the radial ball bearing 14 and is designed to be substantially the same as the inner diameter of the rotor 11.

[0058] The outer circumferential wall 15a has a return flow path 150. The return flow path 150 is located at a front section of the outer circumferential wall 15a and passes through the outer circumferential wall 60a in the radial direction of the housing component 15.

[0059] The front wall 15b is located at the front end of the housing component 15. The front wall 15b extends essentially in the form of a circular flat plate perpendicular to the drive axis O1. The outer circumferential edge of the front wall 15b is connected to the front end of the outer circumferential wall 15a. The front wall 15b has a hub 15d. The hub 15d is formed integrally at the center of the front wall 15b and projects forward from the front wall 15b. The hub 15d is configured to have essentially the same diameter as the inner diameter of the radial ball bearing 14.

[0060] The discharge passage 151 is formed in the hub 15d. The discharge passage 151 extends through the hub 15d and the front wall 15b in the direction of the drive axis O1. As a result, the hub 15d has a cylindrical shape with its center point on the drive axis O1.

[0061] The flange 15c is formed integrally at the rear end of the outer circumferential wall 15a. The flange 15c projects outwards relative to the outer circumferential wall 15a in the radial direction of the housing component 15. As a consequence, the flange 15c has a larger diameter than the rotor 11 and the outer circumferential wall 15a and essentially the same diameter as the drive end plate 31 of the drive worm 30. The flange 15c can be omitted.

[0062] In this compressor, the housing component 15 is fixed to the drive screw 30. Specifically, in the drive screw 30, while the front surface 351 of the cover body 35 faces the rear surface 312 of the drive end plate 31, the cover body 35 is brought into contact with the rear end of the drive circumferential wall 32. The housing component 15 causes the flange 15c to contact the front surface 311 of the drive end plate 31, while it causes the outer circumferential wall 15a of the flange 15c to face the drive end plate 31.

[0063] In this state, the flange 15c, the drive end plate 31, the drive circumferential wall 32, and the cover body 35 are connected by a plurality of bolts from the side of the flange 15c. In this way, the drive end plate 31, the drive circumferential wall 32, and the cover body 35 are integrated into the drive worm 30, and the housing component 15 is integrated with the drive end plate 31 and the drive worm 30.

[0064] By fixing the housing component 15 to the drive worm 30 in this manner, a discharge chamber 16 is formed inside the housing component 15 by the outer circumferential wall 15a and the front wall 15b of the housing component 15 and the drive end plate 31. The inner diameter of the discharge chamber 16 has a second length L2, which is longer than the first length L1. Consequently, the discharge chamber 16 is designed to have a larger diameter than the outer diameter of the radial ball bearing 14. The length of the discharge chamber 16 in the direction of the drive axis O1 is a third length L3. Consequently, the discharge chamber 16 is longer than the stator 17 and the rotor 11 in the direction of the drive axis O1.

[0065] The discharge chamber 16 is connected to the discharge port 38, the return flow path 150, and the discharge passage 151. Here, the discharge port 38 and the discharge passage 151 are connected to the discharge chamber 16 in the direction of the drive axis O1. Conversely, the return flow path 150 is connected to the discharge chamber 16 in the radial direction of the housing component 15, i.e., in the direction perpendicular to the direction of the drive axis O1. The discharge port 38, the return flow path 150, and the discharge passage 151 all have a smaller diameter than the discharge chamber 16.

[0066] In the housing component 15, the outer circumferential wall 15a is fixed to the inner circumferential surface of the rotor 11 while it is inserted into the rotor 11. This means that the housing component 15 is fixed to both the drive screw 30 and the rotor 11 while located inside the rotor 11. At this time, the housing component 15 is fixed to the rotor 11 in such a way that the return flow path 150 to the front side of the rotor 11 is unobstructed, so that the return flow path 150 is not blocked by the rotor 11. In this manner, the housing component 15 is housed in the screw chamber 65. The return flow path 150 is connected to the discharge chamber 16 and the screw chamber 65.

[0067] By fixing the housing component 15 to the rotor 11 in this manner, the housing component 15 is rotatably connected to the rotor 11 in the worm chamber 65 around the drive axis O1. Furthermore, the housing component 15 fits the hub 15d internally onto the inner ring of the radial ball bearing 14. Consequently, the housing component 15 is rotatably supported around the drive axis O1 with respect to the second support section 67, i.e., with respect to the housing 6, via the radial ball bearing 14.

[0068] In this compressor, the output screw 40 is housed within the input screw 30, and the input spiral body 33 and the output spiral body 43 are engaged with each other. Furthermore, the anti-rotation pins 21 are inserted into the respective rings 22. Thus, the input screw 30 and the output screw 40 are assembled in a front-to-back direction, forming a screw compressor section 100. Specifically, the housing component 15, the drive end plate 31, the drive circumferential wall 32, and the cover body 35 are connected by the bolts 50a after the input spiral body 33 and the output spiral body 43 are engaged and the anti-rotation pins 21 are inserted into the rings 22.

[0069] The drive screw 30 and the output screw 40 are assembled to form a suction section 30a through the drive screw 30 and the output screw 40. That is, the drive spiral body 33 and the output spiral body 43 are located within the suction section 30a. The suction section 30a is separated from the screw chamber 65 by the drive end plate 31, the drive circumferential wall 32, and the cover body 35, and is separated from the discharge chamber 16 by the drive end plate 31. The suction section 30a is connected to the suction port 35a.

[0070] In the drive screw 30, the first support section 64 is inserted into the sliding bearing 51, i.e., the hub 36. Thus, the cover body 35 is rotatably supported by the first support section 64 via the sliding bearing 51. As described above, the cover body 35 is supported by the first support section 64, with the suction port 35a facing the screw chamber 65. In this way, the suction port 35a allows the screw chamber 65 and the suction section 35a to be in communication with each other.

[0071] As described above, in this compressor, the housing component 15 is rotatably supported by the second support section 67. Thus, the drive screw 30 is rotatably supported by the housing component 15 through the second support section 67. Consequently, the drive screw 30 is rotatably supported around the drive axis O1 by both the first support section 64 and the second support section 67 within the housing 6.

[0072] On the other hand, in the output screw 40, the output pin 55 is inserted into the pin hole 54 of the first support section 64. Consequently, the output screw 40 is rotatably supported around the output axis O2 by the output pin 55 through the first support section 64. This means that, unlike the drive screw 30, the output screw 40 is rotatably supported around the output axis O2 by the housing 6 only through the first support section 64.

[0073] Here, the output axis O2 is eccentric with respect to the input axis O1. Thus, the output screw 40 is housed in the input screw 30 in an eccentric state with respect to the input screw 30, by being rotatably supported around the output axis O2 by the housing 6.

[0074] In this compressor, designed as described above, the rotation of the rotor 11 drives the drive mechanism 10 and rotates the housing component 15 around the drive axis O1 in the screw chamber 65. The rotation of the housing component 15 also drives and rotates the drive screw 30 around the drive axis O1 in the screw chamber 65. That is to say, in this compressor, although the rotor 11 and the drive screw 30 are not in contact with each other, the rotation of the rotor 11 is transmitted to the drive screw 30 via the housing component 15.

[0075] When the housing component 15 and the drive worm 30 rotate, the anti-rotation pins 21 in the output mechanism 20 rotate relative to the rings 22 around their centers, while making sliding contact with the inner circumferential surfaces of the rings 22. Thus, the output mechanism 20 transmits the torque of the drive worm 30 to the output worm 40.

[0076] As a consequence, the output screw 40 rotates around the output axis O2 through the drive screw 30 and the output mechanism 20. At this time, the output mechanism 20 restricts the rotation of the output screw 40. Consequently, the output screw 40 orbits relative to the drive screw 30 around the output axis O2. When the drive spiral body 33 and the output spiral body 43 rotate in the intake section 30a, they come into contact with each other. Thus, the drive spiral body 33 and the output spiral body 43 form a compression chamber 12 between them.

[0077] When the drive screw 30 and the output screw 40 rotate, the low-pressure refrigerant is drawn into the screw chamber 65 from the outside of the compressor through the pipe and the suction connection port 69, as indicated by an arrow with a dashed line in Fig. The refrigerant, which is drawn into the screw chamber 65, contains lubricating oil 18.

[0078] The refrigerant in the screw chamber 65 is drawn into the compression chamber 12 from the intake port 35a via the intake section 30a. The compression chamber 12 then compresses the refrigerant by reducing its own volume, while confining the refrigerant within itself by rotating the drive screw 30 and the output screw 40. The high-pressure refrigerant, now compressed to the discharge pressure, is discharged from the discharge port 38 to the discharge chamber 16. The refrigerant discharged into the discharge chamber 16 flows through the discharge passage 151 and is discharged to the outside of the compressor via the pipe connected to the discharge connection port 68.

[0079] As described above, since the high-pressure refrigerant is discharged into the discharge chamber 16, the discharge chamber 16 has a higher pressure than the screw chamber 65 and the intake section 30a. In other words, the screw chamber 65 and the intake section 30a have a lower intake atmosphere than the discharge chamber 16.

[0080] In this compressor, the discharge chamber 16 is formed inside the housing component 15. The inner diameter of the discharge chamber 16 is the second length L2, such that the inner diameter is larger than the outer diameter of the radial ball bearing 14. Furthermore, the length of the discharge chamber 16 in the direction of the drive axis O1 is the third length L3. As a result, the volume of the discharge chamber 16 can be adequately ensured in this compressor. Therefore, discharge pulsation when the refrigerant is discharged from the compression chamber 12 to the discharge chamber 16 can be effectively reduced in this compressor. This mode of operation is described in detail below.

[0081] As described above, the refrigerant that has been compressed in the compression chamber 12 is discharged to the discharge chamber 16 through the discharge port 38. Since the discharge port 38 has a smaller diameter than the discharge chamber 16, the refrigerant that has been compressed in the compression chamber 12 flows through the discharge port 38 and is then discharged to the discharge chamber 16, which is a space with a larger volume than the discharge port 38.

[0082] Furthermore, the refrigerant in the discharge chamber 16 is discharged to the outside of the discharge chamber 16, i.e., to the outside of the compressor, by flowing through the discharge passage 151. The hub 15d of the housing component 15 is inserted into the inner ring of the radial ball bearing 14 and supported by the radial ball bearing 14. Therefore, the hub 15d and, consequently, the discharge passage 151 formed in the hub 15d have a smaller diameter than the radial ball bearing 14. That is to say, in this compressor, since the inner diameter of the discharge chamber 16 is larger than the outer diameter of the radial ball bearing 14, the difference between the inner diameter of the discharge chamber 16 and the inner diameter of the discharge passage 151 is sufficiently large.

[0083] Therefore, the refrigerant, which has been compressed in the compression chamber 12, flows through the discharge port 38, the discharge chamber 16, and the discharge passage 151 in that sequence, thus flowing through the narrow space to reach the wide space and then back through the narrow space to be discharged to the outside of the compressor. In this way, the damping effect in the discharge chamber 16 is sufficiently demonstrated in this compressor.

[0084] Furthermore, since the length of the discharge chamber 16 in the direction of the drive axis O1 is the third length L3, the length of the discharge chamber 16 in the direction of the drive axis O1 can be appropriately ensured in this compressor. As a consequence, a low-frequency wavelength of the refrigerant that has been compressed in the compression chamber 12 can be appropriately absorbed in the discharge chamber 16 of the compressor.

[0085] Therefore, in this compressor, a discharge pulsation when the refrigerant is discharged from the compression chamber 12 to the discharge chamber 16 can be appropriately reduced in the discharge chamber 16.

[0086] Furthermore, in this compressor, since the outer diameter of the radial ball bearing 14 is smaller than that of the discharge chamber 16, it is possible to suppress an increase in the diameter of the radial ball bearing 14, even if the diameter of the discharge chamber 16 is increased as described above. In other words, in this compressor, the radial ball bearing 14 does not have the same diameter as the discharge chamber 16, nor does it have a larger diameter. As a consequence, in this compressor, even if the housing component 15 rotates at high speed, the radial ball bearing 14 can adequately support the housing component 15 and, furthermore, the drive screw 30 via the housing component 15.

[0087] Therefore, the compressor of the first embodiment exhibits very low noise levels and excellent reliability.

[0088] Specifically, in this compressor, since the housing component 15 rotates in the screw chamber 65 due to the rotation of the rotor 11, the centrifugal force of the rotating housing component 15 acts on the refrigerant, which is discharged to the discharge chamber 16. As a result, the refrigerant and the lubricating oil 18 can be adequately separated in the discharge chamber 16. The lubricating oil 18, which has been separated from the refrigerant, readily adheres to the inner circumferential surface of the discharge chamber 16 due to the centrifugal force of the housing component 15 and remains readily in the discharge chamber 16 outside the housing component 15 in the radial direction. Therefore, it is less likely that the refrigerant, which is discharged from the discharge port 151 to the outside of the compressor through the pipe of the discharge connection 68, contains the lubricating oil 18.

[0089] The outer circumferential wall 15a of the housing component 15 has the return flow path 150. Therefore, in this compressor, the lubricating oil 18 in the discharge chamber 16 can flow into the screw chamber 65 together with part of the refrigerant through the return flow path 150 due to the centrifugal force acting on the housing component 15, and specifically due to a pressure difference between the inside of the discharge chamber 16 and the inside of the screw chamber 65, in addition to the centrifugal force acting on the housing component 15. The lubricating oil 18 that has flowed from the discharge chamber 16 into the screw chamber 65 is returned to the intake section 30a and the compression chamber 12 together with the refrigerant that is drawn into the intake port 35a.As a consequence, in this compressor, since the interior of the compression chamber 12 can be lubricated by the lubricating oil 18, it is less likely that the drive end plate 31, the drive spiral body 33, the output end plate 41 and the output spiral body 43 will wear out.

[0090] Furthermore, in this compressor the rotor 11, the radial ball bearing 14 and the like can be lubricated by the lubricating oil 18 which flows from the discharge chamber 16 to the screw chamber 65.

[0091] Furthermore, in this compressor, the housing component 15 is fixed to the drive end plate 31 of the drive screw 30, is located inside the rotor 11, and is fixed to the inner circumferential surface of the rotor 11. In this way, by fixing the housing component 15 to the drive end plate 31, the housing component 15 and the discharge chamber 16 can be arranged in front of the compression chamber 12, with the drive end plate 31 positioned between them. This means that in this compressor, the discharge chamber 16 can be arranged close to the compression chamber 12. Therefore, in this compressor, the refrigerant and the lubricating oil 18 can be sufficiently separated in the discharge chamber 16.

[0092] Furthermore, in this compressor, the entire housing component 15 is not located outside the rotor 11. In this way, the length of the discharge chamber 16 in the direction of the drive axis O1 is fixed to the third length L3 in this compressor, and, since the discharge chamber 16 is designed to be long in the direction of the drive axis O1, and its volume is increased accordingly, it is possible to suppress excessive elongation of the housing 6 as a whole.

[0093] Furthermore, in this compressor, since the power of the rotor 11 can be transmitted to the drive screw 30 via the housing component 15, it is not necessary to directly connect the rotor 11 and the drive screw 30 for power transmission. Consequently, the design freedom of the drive screw 30 can be increased in this compressor. As a result, the volume of the compression chamber 12 can be appropriately ensured in this compressor by increasing the diameters of the drive screw 30 and the output screw 40, while minimizing the increase in the diameter of the housing 6. (Second example)

[0094] As in Fig. As shown in Figure 2, the compressor according to the second embodiment is a twin rotary scroll compressor like the compressor according to the first embodiment. The compressor has a housing component 25 instead of the housing component 15. Furthermore, in this compressor, the outer circumferential wall 60a of the housing body 60 is designed to be shorter in the direction of the drive axis O1 than that in the compressor of the first embodiment.

[0095] In this compressor, the cover body 35 has a plurality of recesses 353. Bolts 50c are located in the respective recesses 353. In the drive screw 30, the front surface 351 of the cover body 35 is in contact with the rear end of the drive circumferential wall 32, and the drive end plate 31, the drive circumferential wall 32, and the cover body 35 are connected by the bolts 50c. That is, the bolts 50c do not fix the drive screw 30 to the housing component 25.

[0096] The housing component 25 is a cylindrical component with a base, comprising an outer circumferential wall 25a and a front wall 25b. The outer circumferential wall 25a has a cylindrical shape with its center point on the drive axis O1. Here, the outer diameter of the outer circumferential wall 25a is designed to be larger than that of the outer circumferential wall 15a of the housing component 15 in the compressor of the first embodiment, and is designed to be substantially the same diameter as that of the drive end plate 31. The length of the outer circumferential wall 25a in the direction of the drive axis O1 is shorter than that of the outer circumferential wall 15a of the housing component 15. Furthermore, the outer circumferential wall 25a has a return flow path 250. The return flow path 250 passes through the outer circumferential wall 25a in the radial direction of the housing component 25.

[0097] The front wall 25b is located at the front end of the housing component 25 and extends essentially in the form of a circular, flat plate perpendicular to the drive axis O1. The outer circumferential edge of the front wall 25b is connected to the front end of the outer circumferential wall 25a. The front wall 25b has a hub 25c. The hub 25c is formed integrally at the center of the front wall 25b and projects forward from the front wall 25b. A discharge passage 251 is formed in the hub 25c. The hub 25c and the discharge passage 251 have the same configuration as the hub 15d and the discharge passage 151 in the compressor of the first embodiment.

[0098] In the housing component 25, the rear end of the outer circumferential wall 25a contacts the front surface 311 of the drive end plate 31, while the outer circumferential wall 25a faces the drive end plate 31. In this state, the housing component 25 is connected to the drive end plate 31 by a plurality of bolts 50d. In this way, the housing component 25 is fixed to and integrated with the drive worm 30. The housing component 25, the drive end plate 31, the drive circumferential wall 32, and the cover body 35 can be connected by the bolts 50d or the bolts 50c.

[0099] By fixing the housing component 25 to the drive worm 30 in this manner, a discharge chamber 26 is formed inside the housing component 25 by the outer circumferential wall 25a and the front wall 25b of the housing component 25 and the drive end plate 31. Since the outer diameter of the outer circumferential wall 25a is larger than the outer circumferential wall 15a of the housing component 15, the length of the inner diameter of the discharge chamber 26 is a fourth length L4, which is longer than the second length L2. Consequently, the discharge chamber 26 is designed to have a larger diameter than the outer diameter of the radial ball bearing 14. The length of the discharge chamber 26 in the direction of the drive axis O1 is a fifth length L5, which is shorter than the length of the discharge chamber 16 in the direction of the drive axis O1. The length of the discharge chamber 26 in the direction of the drive axis O1 can be set to the third length L3 or can be longer than the third length L3.

[0100] The discharge chamber 26 is connected to the discharge port 38, the return flow path 215, and the discharge passage 251. The discharge port 38, the return flow path 250, and the discharge passage 251 have a smaller diameter than the discharge chamber 26. The discharge chamber 26 is separated from the intake section 30a by the drive end plate 31.

[0101] The housing component 25 is housed in the worm gear chamber 65. The housing component 25 fits the hub 25c internally onto the inner ring of the radial ball bearing 14. Consequently, the housing component 25 is rotatably supported around the drive axis O1 with respect to the second support section 67 and the housing 6 via the radial ball bearing 14. The return flow path 250 is connected to the discharge chamber 26 and the worm gear chamber 65. The discharge passage 251 faces the discharge connection port 68 in the direction of the drive axis O1.

[0102] The housing component 25 is supported in this manner by the second support section 67, whereby the drive screw 30 is rotatably supported in this compressor by the second support section 67 via the housing component 25. Therefore, in this compressor as well, the drive screw 30 is rotatably supported around the drive axis O1 by the housing 6 through both the first support section 64 and the second support section 67.

[0103] In this compressor, the drive mechanism 10 is arranged behind the housing component 25 in the screw chamber 65. The drive circumferential wall 32 of the drive screw 30 is fixed to the inner circumferential surface of the rotor 11 while it is inserted into the rotor 11. The housing component 25, on the other hand, is not fixed to the rotor 11. Other configurations of this compressor are identical to those of the compressor of the first embodiment, and these configurations are designated with the same reference numerals; a detailed description of the configurations is omitted.

[0104] As indicated by an arrow with a dashed line in Fig. As indicated in the first embodiment, in this compressor, the refrigerant is also drawn into the compression chamber 12 in the screw chamber 65 and compressed. In this compressor, the high-pressure refrigerant, which has been compressed in the compression chamber 12, is discharged from the discharge port 38 to the discharge chamber 26. The refrigerant that has been discharged into the discharge chamber 26 flows through the discharge passage 251 and is discharged to the outside of the compressor through the pipe that is connected to the discharge connection port 68.

[0105] Here, since the inner diameter of the discharge chamber 26 is the fourth length L4, the inner diameter is larger than the outer diameter of the radial ball bearing 14. The length of the discharge chamber 26 in the direction of the drive axis O1 is the fifth length L5. Thus, the compressor can adequately ensure the volume of the discharge chamber 26. Furthermore, since the discharge passage 251 has a smaller diameter than the radial ball bearing 14, the difference between the inner diameter of the discharge chamber 26 and the inner diameter of the discharge passage 251 is sufficiently large.

[0106] In this compressor, the lubricating oil 18, which has been separated from the refrigerant in the discharge chamber 26, can flow into the screw chamber 65 through the return flow path 250. As a result, the compressor can operate in the same way as the compressor of the first embodiment.

[0107] Specifically, in this compressor, the drive circumferential wall 32 is fixed to the inner circumferential surface of the rotor 11, while it is located inside the rotor 11, and the housing component 25 is fixed to the drive end plate 31 of the drive screw 30. Consequently, in this compressor as well, since the discharge chamber 26 can be arranged close to the compression chamber 12, the refrigerant and the lubricating oil 18 can be sufficiently separated in the discharge chamber 26.

[0108] Furthermore, in this compressor it is not necessary to arrange the housing component 25 inside the rotor 11, and thus the degree of freedom in the design of the housing component 25 is correspondingly increased. As a consequence, the diameter of the discharge chamber 26 in this compressor can be increased to the fourth length L4 by setting the inner diameter of the discharge chamber 26. In this way, discharge pulsation in the discharge chamber 26, when the refrigerant is discharged from the compression chamber 12 to the discharge chamber 26, can be appropriately reduced.

[0109] In this compressor, by setting the length of the discharge chamber 26 in the direction of the drive axis O1 to the fifth length L5, it is possible to reduce the size of the housing component 25 in the direction of the drive axis O1, while the discharge pulsation in the discharge chamber 26 is suitably reduced, as described above. As a consequence, it is possible in this compressor to shorten the axis of the housing 6 compared to the compressor of the first embodiment.

[0110] Furthermore, in this compressor, since the power of the rotor 11 can be transmitted to the housing component 25 via the drive screw 30, it is not necessary to directly connect the rotor 11 and the housing component 25 for power transmission. In this respect as well, the compressor offers a high degree of freedom in the design of the housing component 25. (Third embodiment)

[0111] As in Fig. As shown in Figure 3, the compressor according to the third embodiment has a housing 7, a drive mechanism 80, a fixed screw 90, a movable screw 110, and a housing component 27. The fixed screw 90 is an example of a "first screw" according to the present invention. The movable screw 110 is an example of a "second screw" in the present invention.

[0112] The housing 7 has a motor housing 71, a compressor housing 72 and a fixing block 73. The motor housing 71 forms a rear section of the housing 7, and the compressor housing 72 forms a front section of the housing 7.

[0113] The motor housing 71 has a rear wall 71a and a first circumferential wall 71b. The rear wall 71a is located at the rear end of the motor housing 71 and extends radially along the motor housing 71. The first circumferential wall 71b is connected to the rear wall 71a and extends forward from the rear wall 71a in a substantially cylindrical shape. Together with the rear wall 71a and the first circumferential wall 71b, the motor housing 71 has a cylindrical shape with a bottom and a front opening. A motor chamber 75 is formed in the motor housing 71.

[0114] The motor housing 71 is provided with an intake connection 71c, a support section 71d, and a discharge connection 71e. The first circumferential wall 71b has the intake connection 71c. The intake connection 71c extends through the first circumferential wall 71b in the radial direction of the motor housing 71. As with the intake connection 69 of the compressor in the first embodiment, a pipe (not shown) is connected to the intake connection 71c. Consequently, the intake connection 71c is connected to the outside of the compressor through the pipe. The intake connection 71c is in communication with the motor chamber 75. The rear wall 71a can also have the intake connection 71c.

[0115] The support section 71d has a cylindrical shape with its center on a drive axis O3 and projects from the center of the rear wall 71a into the interior of the motor chamber 75. Here, the drive axis O3 is parallel to the front-to-back direction. The support section 71d is provided with a radial ball bearing 39. The radial ball bearing 39 is an example of a "bearing" in the present invention. The length of the outer diameter of the radial ball bearing 39 is a sixth length L6 and is smaller than the support section 71d. The radial ball bearing 39 is fixed to the support section 71d by fitting an outer ring into the support section 71d.

[0116] The discharge connection port 71e is located in the support section 71d of the rear wall 71a. The discharge connection port 71e has a smaller diameter than a discharge chamber 28, which will be described later, and extends through the rear wall 71a in the direction of the drive axis O3. As with the discharge connection port 68 in the compressor of the first embodiment, a pipe (not shown) is connected to the discharge connection port 71e. Therefore, the discharge connection port 71e is connected to the outside of the compressor through the pipe.

[0117] The compressor housing 72 has a front wall 72a and a second circumferential wall 72b. The front wall 72a is located at the front end of the compressor housing 72 and extends radially along the housing. The second circumferential wall 72b is connected to the front wall 72a and extends rearward from the front wall 72a in a cylindrical shape. Together with the front wall 72a and the second circumferential wall 72b, the compressor housing 72 has a cylindrical shape with a bottom and a rear opening.

[0118] The fixing block 73 is provided between the motor housing 71 and the compressor housing 72. The motor housing 71, the compressor housing 72, and the fixing block 73 are fastened to each other by a plurality of bolts 78 from the side of the compressor housing 72. In this way, the fixing block 73 is fixed to the motor housing 71 and the compressor housing 72, while being sandwiched between them. Consequently, the fixing block 73 is located between the motor chamber 75 and the movable screw 110 in the front-to-back direction. Fig. Figure 3 shows only one of the multiple bolts 78. A method for fixing the motor housing 71, the compressor housing 72 and the fixing block 73 can be designed appropriately.

[0119] The fixing block 73 has a hub 73a that projects rearward. An insertion hole 73b is formed at the distal end of the hub 73a. A radial ball bearing 45 and a shaft seal component 29 are provided in the hub 73a. Furthermore, the fixing block 73 has a connecting passage 73c. ​​The connecting passage 73c is located outside the hub 73a within the fixing block 73 and extends through the fixing block 73 in the direction of the drive axis O3. The number of connecting passages 73c can be configured as appropriate.

[0120] Furthermore, six anti-rotation pins 47 are fixed to the fixing block 73 in a forward-protruding position. The anti-rotation pins 47 are arranged at equal intervals around the circumference of the fixing block 73. Fig. Figure 3 shows one of the six anti-rotation pins 47.

[0121] The drive mechanism 80 is housed in the motor chamber 75. The drive mechanism 80 has a stator 81, a rotor 82, and a drive shaft 83. The stator 81 has a stator core 81a and a coil end 81b. The inner circumference of a rear end of the coil end 81b is inclined to prevent engagement with a counterweight 86, which will be described later. It should be noted that the stator core 81a and the coil end 81b have essentially the same design as the stator core 17a and the coil end 81b in the compressor of the first embodiment, except for the shape of the coil end 17b, which has been described above, and thus a detailed description of it is omitted. The stator 81 is fixed to the motor housing 71 by fitting the stator core 81a into the inner circumferential surface of the first circumferential wall 71b.

[0122] The rotor 82 has a cylindrical shape around the drive shaft O3 and is arranged in the stator 81. Although not shown in detail, the rotor 82 also has a multitude of permanent magnets and a multitude of electromagnetic steel plates for fixing the permanent magnets.

[0123] The drive shaft 83 is fixed to the rotor 82 in such a way that it projects forward and backward from the rotor 82 in the direction of the drive axis O3. The front end of the drive shaft 83 corresponds to "one end of the drive shaft" in the present invention, and the rear end of the drive shaft 83 corresponds to the "other end of the drive shaft" in the present invention.

[0124] The front section of the drive shaft 83, including its front end, is inserted into the insertion hole 73b of the fixing block 73 and enters the hub 73a. The front end section of the drive shaft 83 is rotatably supported in the hub 73a by the radial ball bearing 45. Thus, the drive shaft 83 is rotatable about the drive axis O3 within the housing 7. A space between the fixing block 73 and the drive shaft 83 is sealed by the shaft seal component 29.

[0125] A wave path 84 is formed inside the drive shaft 83. The wave path 84 passes through the interior of the drive shaft 83 in the direction of the drive axis O3. As a result, the front end of the wave path 84 is open to a front end surface 83a of the drive shaft 83, and the rear end of the wave path 84 is open to a rear end surface 83b of the drive shaft 83.

[0126] An eccentric pin 85 is fixed to the front end face 83a of the drive shaft 83. The eccentric pin 85 is positioned eccentrically from the drive axis O3 relative to the front end face 83a. The eccentric pin 85 engages the hub 73a when the drive shaft 83 is inserted into the insertion hole 73b. The eccentric pin 85 fits a bushing 49 in the hub 73a. The bushing 49 has a connecting hole 49a. The connecting hole 49a extends through the bushing 49 in the direction of the drive axis O3.

[0127] The counterweight 86 is formed integrally with the drive shaft 83. The counterweight 86 is positioned eccentrically to the drive shaft O3. Specifically, the counterweight 86 is positioned opposite the eccentric pin 85, with the drive shaft O3 located between them.

[0128] The counterweight 86 is positioned between the fixing block 73 and the rotor 82 in the motor chamber 75 by inserting the drive shaft 83 into the insertion hole 73b. Although not shown in detail, the counterweight 86 essentially has a fan-shaped plate form and extends away from the drive shaft 83 in the radial direction of the drive shaft 83. It should be noted that the shape of the counterweight 86 can be designed as is suitable.

[0129] The fixed screw 90 is fixed to and located within the compressor housing 72. The fixed screw 90 has a fixed end plate 90a, a fixed circumferential wall 90b, and a fixed spiral body 90c. The fixed end plate 90a is located at the front end of the fixed screw 90 and has a disc shape extending perpendicular to the drive axis O3.

[0130] The fixed circumferential wall 90b is formed integrally with the fixed end plate 90a. The fixed circumferential wall 90b is connected to the fixed end plate 90a at the outer circumference of the fixed end plate 90a and extends rearward in a cylindrical shape, i.e., towards the movable screw 110. The fixed circumferential wall 90b has an intake port 90f. The intake port 90f passes radially through the fixed circumferential wall 90b. Consequently, the intake port 90f opens into the compressor housing 72 and is connected to it. The fixed spiral body 90c is formed integrally with the fixed end plate 90a inside the fixed circumferential wall 90b. The fixed spiral body 90c projects in a spiral shape towards the movable screw 110 in the direction of the drive axis O3.

[0131] The movable screw 110 is provided in the compressor housing 72 and is located between the fixed screw 90 and the fixing block 73. The movable screw 110 has a movable end plate 110a and a movable spiral body 110b.

[0132] The movable end plate 110a is located at the rear end of the movable screw 110 and has a disc shape that extends perpendicular to the drive axis O3. The movable end plate 110a has a housing section 46 and a discharge port 44.

[0133] The housing section 46 is recessed forward from the rear end face of the movable end plate 110a in a substantially column-like shape. The output port 44 is located in the housing section 46 at a position relative to the movable end plate 110a and passes through the movable end plate 110a in the direction of the drive axis O3. Therefore, the output port 44 is in contact with the interior of the housing section 46.

[0134] The dispensing diaphragm valve 57 and the retainer 58 are fixed to the movable end plate 110a by fixing bolts 59. The dispensing diaphragm valve 57, the retainer 58, and the fixing bolt 59 are arranged in the housing section 46. As a result, the dispensing diaphragm valve 57 can open and close the dispensing port 44.

[0135] Furthermore, the bushing 49 is rotatably mounted in the housing section 46 behind the discharge diaphragm valve 57, the retainer 58, and the locking bolt 59. Here, the bushing 49 is not in contact with the locking bolt 59 or similar components. By mounting the bushing 49 in the housing section 46 in this manner, the movable worm gear 110 is connected to the front end of the drive shaft 83 at a position that is eccentric to the drive axis O3 through the bushing 49 and the eccentric pin 85. The connecting hole 49a of the bushing 49 is connected to the interior of the housing section 46 at its front end. The rear end of the connecting hole 49a faces the shaft path 84 of the drive shaft 83. The bushing 49 can be mounted in the housing section 46 via a plain bearing, a ball bearing, or the like.

[0136] The movable end plate 110a is provided with the same number of rings 48 as the anti-rotation pins 47. Each ring 48 is designed to receive the distal end of the anti-rotation pin 47 in a clearance fit. The anti-rotation pins 47 and the rings 48 form an anti-rotation mechanism. Fig. Figure 3 is one of the six rings 48 shown. The number of anti-rotation pins 47 and the number of rings 48 forming the anti-rotation mechanism can be changed as appropriate, as long as the number is three or more.

[0137] The movable spiral body 110b is formed integrally with the movable end plate 110a and extends towards the fixed end plate 90a.

[0138] The fixed screw 90 and the movable screw 110 are assembled in a front-to-back direction to form a screw compression section 100a. When the fixed spiral body 90c and the movable spiral body 110b are engaged, a compression chamber 12a is formed between the fixed screw 90 and the movable screw 110 by the fixed end plate 90a, the fixed spiral body 90c, the movable end plate 110a, and the movable spiral body 110b. The compression chamber 12a changes volume by a rotation of the movable screw 110. As a consequence, the compression chamber 12a is connected to the intake port 90f and the discharge port 44.

[0139] A pressure plate 92 is provided between the movable screw 110 and the fixing block 73. The pressure plate 92 is formed from a thin metal plate and is in contact with the movable screw 110 and the fixing block 73. The pressure plate 92 can push the movable screw 110 forward, i.e., towards the fixed screw 90, by means of a restoring force generated as a result of elastic deformation. Furthermore, a counter-pressure chamber 93 is formed in the hub 73a of the fixing block 73 by the movable end plate 110a and the pressure plate 92. The counter-pressure chamber 93 is connected to the connecting hole 49a and the shaft path 84 between the connecting hole 49a and the shaft path 84.

[0140] The housing component 27 has a main body 27a and a cover 27b. The main body 27a has an outer circumferential wall 271 and a front wall 272 and is cylindrical with a base. The outer circumferential wall 271 is cylindrical with its center point on the drive shaft O3. The outer diameter of the outer circumferential wall 271 is larger than the outer diameter of the radial ball bearing 39. The outer circumferential wall 271 has a return flow path 270. The return flow path 270 passes through the outer circumferential wall 271 in the radial direction of the main body 27a.

[0141] The front wall 272 is located at the front end of the main body 27a and thus at the front end of the housing component 27. The front wall 272 extends essentially in the form of a circular flat plate perpendicular to the drive axis O3. The outer circumferential edge of the front wall 272 is connected to the front end of the outer circumferential wall 271. The front wall 272 has a mounting hole 27c. The mounting hole 27c is formed integrally at the center of the front wall 272 and extends through the front wall 272 in the direction of the drive axis O3. The mounting hole 27c is designed to have essentially the same diameter as the drive shaft 83.

[0142] The cover 27b is configured to have substantially the same diameter as the outer diameter of the outer circumferential wall 271 and extends substantially in the form of a circular flat plate perpendicular to the drive axis O3. The cover 27b has a hub 27d. The hub 27d is formed in one piece at the center of the cover 27b and projects rearward from the cover 27b. The hub 27d has a smaller diameter than the outer diameter of the radial ball bearing 39 and is configured to have substantially the same diameter as the inner ring of the radial ball bearing 39.

[0143] A discharge passage 273 is formed in the hub 27d. The discharge passage 273 extends through the interior of the hub 27d and the interior of the cover 27b in the direction of the drive axis O3. As a result, the hub 27d has a cylindrical shape with its center point on the drive axis O3.

[0144] In the housing component 27, the outer circumferential wall 271 and the cover 27b are connected by a plurality of bolts 50e, with the cover 27b being in contact with the rear end of the outer circumferential wall 271. Thus, the main body 27a and the cover 27b are fixed and integrated. In this way, the discharge chamber 28 is formed in the housing component 27 by the outer circumferential wall 271, the front wall 272, and the cover 27b. Here, the length of the inner diameter of the discharge chamber 28 is a seventh length L7, which is longer than the sixth length L6. Consequently, the discharge chamber 28 is designed to have a larger diameter than the outer diameter of the radial ball bearing 39. The length of the discharge chamber 28 in the direction of the drive axis O3 is an eighth length L8.

[0145] The discharge chamber 28 is connected to the recirculation flow path 270 and the discharge passage 273. Both the recirculation flow path 270 and the discharge passage 273 have a smaller diameter than the discharge chamber 28. The housing component 27 is fixed to the drive shaft 83, with the rear end of the drive shaft 83 inserted into the mounting hole 27c. Consequently, the housing component 27 is located in the motor chamber 75 and is rotatable around the drive axis O3 as a single unit with the drive shaft 83. The shaft path 84 of the drive shaft 83 faces the interior of the discharge chamber 28. Consequently, the discharge chamber 28 is connected to the shaft path 84. As a consequence, the discharge chamber 28 is connected to the compression chamber 12a by the wave path 84, the counter-pressure chamber 93, the connecting hole 49a, the accommodation section 46 and the discharge port 44.

[0146] In the housing component 27, the hub 27d fits into the inner ring of the radial ball bearing 39. Thus, the housing component 27 is supported by the support section 71d via the radial ball bearing 39. Since the housing component 27 is supported in this way by the support section 71d, the discharge passage 273 faces the discharge connection port 71e. When the housing component 27 is supported by the support section 71d, the drive shaft 83 is supported by the support section 71d via the housing component 27 and the radial ball bearing 39. In this way, the housing component 27 and the drive shaft 83 are rotatable about the drive axis O3 with respect to the support section 71d.

[0147] In this compressor, as indicated by an arrow with a dashed line in Fig.As indicated in Figure 3, the low-pressure refrigerant is drawn into the motor chamber 75 from the outside of the compressor through the intake connection 71c. Furthermore, in this compressor, the drive shaft 83 rotates around the drive axis O3 due to the rotation of the rotor 82. As a consequence, the movable screw 110 rotates, the movable end plate 110a slides on the distal end of the fixed spiral body 90c, and the fixed spiral body 90c and the movable spiral body 110b slide against each other. At this time, the anti-rotation mechanism restricts the rotation of the movable screw 110, and the movable screw 110 only rotates relative to the fixed screw 90.

[0148] The refrigerant in the motor chamber 75 flows through the connecting passage 73c and the intake port 90f and is drawn into the compression chamber 12a. The compression chamber 12a compresses the internal refrigerant while reducing its volume through the rotation of the movable screw 110. The high-pressure refrigerant, thus compressed in the compression chamber 12a, is discharged from the discharge port 44 to the outside of the compression chamber 12a, i.e., into the housing section 46. The high-pressure refrigerant, having been discharged into the housing section 46 in this manner, flows through the connecting hole 49a, the back pressure chamber 93, and the shaft path 84 in that order and is discharged into the discharge chamber 28.

[0149] As described above, in this compressor the low-pressure refrigerant is drawn into the motor chamber 75 from the outside of the compressor, and the high-pressure refrigerant is discharged into the discharge chamber 28. Therefore, the motor chamber 75 has a lower pressure than the discharge chamber 28 and has a different intake atmosphere.

[0150] The refrigerant in the discharge chamber 28 flows through the discharge passage 273 and is discharged to the outside of the compressor through the pipe connected to the discharge connection port 71e. Since the inner diameter of the discharge chamber 28 is the seventh length L7, it is larger than the outer diameter of the radial ball bearing 39. Furthermore, the length of the discharge chamber 28 in the direction of the drive axis O3 is the eighth length L8. Thus, the compressor can adequately maintain the volume of the discharge chamber 28. Moreover, since the discharge passage 273 has a smaller diameter than the radial ball bearing 39, the difference between the inner diameter of the discharge chamber 28 and the inner diameter of the discharge passage 273 is sufficiently large.

[0151] Furthermore, in this compressor, since the housing component 27 rotates in the motor chamber 75 due to the rotation of the drive shaft 83, the centrifugal force of the rotating housing component 27 acts on the refrigerant, which is discharged to the discharge chamber 28. Consequently, in this compressor as well, the refrigerant and the lubricating oil 18 can be adequately separated in the discharge chamber 28. The lubricating oil 18, which has been separated from the refrigerant in the discharge chamber 28, can flow out of the return flow path 270 into the motor chamber 75 in an appropriate manner due to the centrifugal force acting on the housing component 27 and the pressure difference between the interior of the discharge chamber 28 and the interior of the motor chamber 75. As a result, the drive shaft 83, the radial ball bearing 39, and the like can be adequately lubricated in this compressor by the lubricating oil 18 in the motor chamber 75.Furthermore, the lubricating oil 18 in the motor chamber 75 is returned to the compression chamber 12a together with the refrigerant that flows through the motor chamber 75 towards the compression chamber 12a. As a result, the compressor can operate in the same way as the compressor of the first embodiment.

[0152] The present invention is described in the foregoing according to the first to third embodiments, but the present invention is not limited to the first to third embodiments described above, and it need not be said that the present invention can be modified and applied in a suitable manner without departing from its core.

[0153] For example, in the compressor according to the first embodiment, the drive screw 30 and the output screw 40 are assembled in a state in which the output screw 40 is housed within the drive screw 30. However, the present invention is not limited to this, and the drive screw 30 and the output screw 40 can be assembled with the output screw 40 arranged on the outside of the drive screw 30. In this case, the output end plate 41 and the housing component 15 can be fixed to one another. The same applies to the compressor of the second embodiment.

[0154] In the compressor according to the third embodiment, the housing component 27 is fixed to the drive shaft 83. However, the present invention is not limited thereto, and the housing component 27 can be designed to rotate in the motor chamber 75 by the rotation of the rotor 82 by fixing the housing component 27 to the rotor 82.

[0155] In the compressor according to the first embodiment, the drive screw 30, the housing component 15, and the rotor 11 can be arranged remotely from one another in the direction of the drive axis O1 by connecting the drive screw 30 and the rotor 11 in order to be able to transmit power through the shaft body. The same applies to the compressor of the second embodiment.

[0156] In the compressors of the first and second embodiments, the output mechanism 20 has the anti-rotation pin 21 and the ring 22. However, the present invention is not limited thereto, and the output mechanism 20 can be designed by a pin-ring-pin method in which two pins with an inner circumferential surface of a free ring are in sliding contact, a pin-pin method in which outer circumferential surfaces of two pins are in sliding contact with each other, a method that uses an Oldham coupling, or the like. The same applies to the anti-rotation mechanism in the compressor of the third embodiment. COMMERCIAL APPLICABILITY

[0157] The present invention is applicable to an air conditioning system of a vehicle. REFERENCE MARK LIST 6, 7 Housing 10.80 Drive mechanism 11, 82 Rotor 12, 12a Compression chamber 14, 39 radial ball bearings (bearings) 15, 25, 27 Housing component 16, 26, 28 Collection Chamber 17, 81 Stator 18 Lubricating oil 20 Output mechanism 30 Drive screw (first screw) 40 discharge screw (second screw) 83 Drive shaft 84 Wave path 90 fixed snail (first snail) 110 movable worms (second worm) 150, 250, 270 Recirculation path O1, O3 drive axle O2 output shaft QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 02-227575

[0006]

Claims

[1] Scroll compressor with: a housing, a drive mechanism, a first screw and a second screw, wherein the drive mechanism, the first worm and the second worm are housed in the casing, a compression chamber that compresses a refrigerant and is formed by the first screw and the second screw, wherein a housing component is fixed to at least one component of the components first screw, second screw and drive mechanism, wherein the housing component is provided with a discharge chamber which is connected to the compression chamber and from which a refrigerant which has been compressed in the compression chamber is discharged, the housing component is supported in the housing by a bearing in a rotatable manner, and The discharge chamber is designed to have a diameter larger than the outer diameter of the bearing. [2] Scroll compressor according to claim 1, wherein Lubricating oil is delivered to the delivery chamber together with the refrigerant that has been compressed in the compression chamber, and the housing component has a return flow path that returns the lubricating oil in the housing component to a section in the housing that has a lower pressure than the delivery chamber. [3] Scroll compressor according to claim 1 or 2, wherein the first worm is driven around a drive axis by the drive mechanism, the second screw follows the first screw and a drive mechanism in a rotating manner around a drive axis, while being eccentric with respect to the first screw, and the housing component is fixed to the first screw. [4] Scroll compressor according to claim 3, wherein The drive mechanism has a stator that is fixed in the housing and a rotor that is tubular and rotatable within the stator, and the housing component is located inside the rotor. [5] Scroll compressor according to claim 1 or 2, wherein the first worm is driven around a drive axis by the drive mechanism, The second screw follows the first screw and the output mechanism in a rotating manner around an output axis, while being eccentric with respect to the first screw. The drive mechanism has a stator that is fixed in the housing and a rotor that is designed in a tubular shape and is rotatable in the stator. the first screw is located inside the rotor, and the housing component is fixed to the first screw. [6] Scroll compressor according to claim 1 or 2, wherein The drive mechanism has a stator that is fixed to the housing, a rotor that is formed in a raw shape and is rotatable in the stator, and a drive shaft that is fixed to the rotor and is rotatable together with the rotor. the first snail is fixed to the shell, and the second worm is connected to one end of the drive shaft and rotates relative to the first worm by a rotation of the drive shaft, the housing component is fixed to the other end of the drive shaft, and A wave path extending from one end to the other, allowing the compression chamber and the discharge chamber to be interconnected, is formed inside the drive shaft.

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