COUPLING SPIRAL COMPRESSOR

Abstract

A constant-speed spiral compressor has a housing (6) with an outlet section (63) and a compression mechanism (14) arranged in the housing (6). The compression mechanism (14) has a compression chamber (12), an outlet chamber (91, 92, 93, 94, 95), and a rotating shaft section (37d, 81d, 72d, 85d, 87b) which is supported by the housing (6) via a bearing (52). The outlet chamber (91, 92, 93, 94, 95) has a larger diameter than the bearing (52). The rotating shaft section (37d, 81d, 72d, 85d, 87b) has an outlet communication section (82, 84) through which fluid is discharged into the outlet chamber (91, 92, 93, 94, 95) to flow to the outlet section (63). A change in phase between the outlet section (63) and the outlet communication section (82, 84) with rotation of the rotating shaft section (37d, 81d, 72d, 85d, 87b) changes a flow resistance for the fluid flowing from the outlet communication section (82, 84) to the outlet section (63).The outlet section (63) and the outlet communication section (82, 84) reach a phase in which the flow resistance increases, while the flow rate of the fluid discharged from the compression chamber (12) to the outlet chamber (91, 92, 93, 94, 95) approaches a maximum.

Description

Background of the invention: Technical field

[0001] The following disclosure relates to a synchronous spiral compressor. State of the art

[0002] Japanese patent application JP 2002-310073 discloses a conventional constant-speed spiral compressor (hereinafter referred to simply as a compressor). The compressor comprises a casing and a compression mechanism arranged within the casing. The casing has an outlet section through which fluid is discharged to an outside, an inlet section through which fluid is drawn in from the outside, and an inlet chamber in (fluid) communication with the inlet section.

[0003] The compression mechanism comprises a drive screw and a driven screw. The drive screw is equipped with a drive shaft. The drive shaft is rotatably mounted in the housing via a bearing. The drive screw is driven by a drive mechanism to rotate around a pivot axis. The drive screw has a drive screw end plate and a drive screw spiral body, which is integrally formed with the drive screw end plate and projects in a spiral shape towards the driven screw.

[0004] The driven screw faces the drive screw. The driven screw is equipped with a driven shaft. The driven shaft is rotatably mounted in the housing via a bearing. The driven screw is eccentrically positioned relative to the drive screw and is rotated about an output axis by the drive screw and the driven mechanism. A compression chamber is defined between the driven screw and the drive screw. The driven screw has a driven screw end plate and a driven screw spiral body, which is integrally formed with the driven screw end plate and projects in a spiral shape towards the drive screw. Additionally, an outlet chamber is formed within the driven shaft. The outlet chamber is in fluid communication with the compression chamber and also with the outlet section.

[0005] In this compressor, fluid is drawn into the inlet chamber from the outside of the casing through the inlet section. With this compression mechanism, the volume of the compression chamber changes with the rotation of the drive screw and the driven screw. Consequently, fluid is drawn from the inlet chamber into the compression chamber and compressed there, thus reducing the volume of the compression chamber. The compressed fluid is then discharged from the compression chamber to the outlet chamber and from the outlet section to the outside of the casing.

[0006] With this type of compressor, it is necessary to reduce noise caused by outlet pulsation during operation. Therefore, with the conventional compressor mentioned above, reducing outlet pulsation is considered by increasing the volume of the outlet chamber and enhancing its damping effect. However, since the outlet chamber in the conventional compressor is located within the driven shaft of the screw, the diameter of the driven shaft increases with the volume of the outlet chamber, thus increasing the diameter of the bearing supporting the driven shaft. This increases energy losses in the bearing, leading to a decrease in compressor efficiency.

[0007] The present invention, which was made in view of the conventional circumstances described above, is aimed at providing a synchronous spiral compressor that achieves high smoothness of operation and suppresses a decrease in efficiency. Summary of the invention

[0008] According to one aspect of the present invention, a synchronous spiral compressor is provided, comprising: a housing with an outlet section through which fluid is discharged to an outside; and a compression mechanism arranged in the housing. The compression mechanism has a compression chamber in which fluid is compressed while a volume of the compression chamber is reduced; an outlet chamber which is in fluid communication with the compression chamber and into which the fluid compressed in the compression chamber is discharged; and a rotating shaft section which is supported by the housing via a bearing so as to be rotatable about an axis of rotation. The compression mechanism has a drive screw and a driven screw, the drive screw being configured to be rotated by a drive mechanism.and a drive screw end plate and a drive screw spiral body, which is formed integrally with the drive screw end plate and projects in a spiral shape towards the driven screw, wherein the driven screw faces the drive screw and is configured to be rotated by the drive screw and a driven mechanism at an eccentric position with respect to the drive screw in order to form the compression chamber between the drive screw and the driven screw, wherein the driven screw has a driven screw end plate and a driven screw spiral body, which is formed integrally with the driven screw end plate and projects in a spiral shape towards the drive screw. The outlet chamber has a diameterwhich is larger than the outer diameter of the bearing. The rotating shaft section has an outlet communication section through which the fluid is discharged into the outlet chamber in order to flow to the outlet section. A phase change (or phase shift) between the outlet section and the outlet communication section, with rotation of the rotating shaft section, alters the flow resistance for the fluid flowing to / from the outlet communication section to the outlet section. The outlet section and the outlet communication section reach a phase in which the flow resistance increases, while / as the flow rate of the fluid discharged from / to the compression chamber to / from the outlet chamber approaches a maximum. Brief description of the characters

[0009] The invention, together with its subject matter and advantages, can best be understood by reference to the following description of the embodiments together with the accompanying drawings, in which: Fig. 1 a cross-sectional view of a synchronous spiral compressor of a first embodiment; Fig. 2 a partially enlarged cross-sectional view illustrating a main part of the synchronous spiral compressor of the first embodiment with an outlet communication section, a second insertion hole and an outlet channel; Fig. 3 a diagram showing a relationship between a change in the rotational phase between a drive screw and a driven screw and a change in the volume of a compression chamber in the synchronous spiral compressor of the first embodiment; Fig. 4 a diagram showing a relationship between the change in a rotational phase between the drive screw and the driven screw and a change in a pressure in the compression chamber in the synchronous spiral compressor of the first embodiment; Fig. Figure 5 shows a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line VV. Fig. 1, if the rotation phase between the drive screw and the driven screw is at phase X1; Fig. Figure 6 shows a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line VV. Fig. 1, if the rotation phase between the drive screw and the driven screw is at phase X2; Fig. Figure 7 shows a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line VV. Fig. 1, if the rotation phase between the drive screw and the driven screw is at phase X3; Fig. Figure 8 shows a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line VV. Fig. 1, if the rotation phase between the drive screw and the driven screw is at phase X4; Fig. Figure 9 shows a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line IX-IX of Fig. 1, if the rotation phase between the drive screw and the driven screw is at phase X4; Fig. 10 is a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line VV of Fig. 1, when the rotation phase between the drive screw and the driven screw is at phase X5; Fig. 11 is a cross-sectional view of the synchronous spiral compressor of the first embodiment, taken along line IX-IX of Fig. 1, when the rotation phase between the drive screw and the driven screw is at phase X5; Fig. 12 a diagram showing a waveform of an outlet pulsation and a waveform of a compensating pulsation during operation of the synchronous spiral compressor of the first embodiment; Fig. 13 a partial cross-sectional view of the constant-speed spiral compressor of the first embodiment, illustrating a condition in which lubricating oil accumulates in the outlet chamber when the compression mechanism rotates at a high speed; Fig. 14 is a cross-sectional view of a synchronous spiral compressor of a second embodiment; Fig. Figures 15A to 15D each represent a schematic view of the synchronous spiral compressor of the second embodiment, illustrating a phase change between an outlet section and an outlet communication section corresponding to / depending on (a) rotary drive of the drive screw, when the outlet section and the outlet communication section are oriented in a D1 direction. Fig. 14 are considered; in particular, they illustrate Fig. 15A a phase between the outlet section and the outlet communication section when the rotation angle of the drive screw is zero; illustrated Fig. 15B the phase between the outlet section and the outlet communication section, when the drive screw moves approximately 90 degrees out of the in Fig. 15A illustrates the state rotates; illustrates Fig. 15C the phase between the outlet section and the outlet communication section, when the drive screw moves approximately 90 degrees out of the in Fig. 15B illustrates the state rotates; and illustrates Fig. 15D the phase between the outlet section and the outlet communication section, when the drive screw moves approximately 90 degrees out of the in Fig. 15C illustrates the state rotates; Fig. 16 is an enlarged cross-sectional view illustrating a main part of a synchronous spiral compressor of a third embodiment; Fig. 17 a cross-sectional view of a synchronous spiral compressor of a fourth embodiment; and Fig. Figure 18 shows a cross-sectional view of a synchronous spiral compressor of a fifth embodiment. Detailed description of the embodiments

[0010] The first to fifth embodiments of the present invention are described below with reference to the drawings. A synchronous spiral compressor according to each of the first to fifth embodiments is mounted on a vehicle (not shown) and serves as a component of the vehicle's air conditioning system. First embodiment

[0011] As in Fig. As illustrated in Figure 1, the synchronous spiral compressor (hereinafter simply referred to as a compressor) of the first embodiment comprises a housing 6, an electric motor 10, and a compression mechanism 14. The electric motor 10 is an example of a "drive mechanism" of the present invention.

[0012] In the present embodiment, a front-back direction of the compressor is defined by a Fig. The solid arrow in Figure 1 defines the front-back directions of the compressor. Fig. 2 and thereafter correspond to the front-back direction in Fig. 1. It should be noted that the front-to-back direction is an example of the expediency of the explanation, and the position of the compressor may be changed as appropriate, depending on the vehicle on which the compressor is / will be mounted.

[0013] As in Fig. As illustrated in Figure 1, the housing 6 comprises a housing body 60 and a housing cover 62. The housing body 60 and the housing cover 62 are made of an aluminum alloy.

[0014] The housing body 60 is a flattened tubular element; and has an outer circumferential wall 60a and a rear wall 60b. The outer circumferential wall 60a has a cylindrical shape that extends around an axis of rotation O1. The axis of rotation O1 is parallel to the front-to-back direction.

[0015] Additionally, an inlet communication port 68 is formed in the outer circumferential wall 60a. The inlet communication port 68 extends radially along the housing body 60. The inlet communication port 68 is connected to an evaporator (not shown) via a pipe (not shown).

[0016] The rear wall 60b is located at a rear end of the housing body 60. The rear wall 60b extends in a substantially circular, flat plate shape, perpendicular to the axis of rotation O1. An outer circumferential edge of the rear wall 60b is connected to a rear end of the outer circumferential wall 60a. The inlet communication port 68 can be formed in the rear wall 60b.

[0017] The back wall 60b has a first bearing section 64 at / in the middle of an inner surface of the back wall 60b. The first bearing section 64 projects forward from the middle of the inner surface of the back wall 60b. The first bearing section 64 has a column shape that extends around the axis of rotation O1.

[0018] The first bearing section 64 has a pin hole 4. The pin hole 4 extends in a column shape, is open at a front end face of the first bearing section 64 and extends backwards in a straight line within the first bearing section 64. This pin hole 4 does not extend through the first bearing section 64 in the front-to-back direction.

[0019] A first plain bearing 51 is provided on an outer circumferential surface of the first bearing section 64. The first plain bearing 51 has a cylindrical shape with a larger diameter than that of the first bearing section 64. The first plain bearing 51 is arranged on the outer circumferential surface of the first bearing section 64. The first plain bearing 51 can be replaced by a ball bearing.

[0020] The housing cover 62 is arranged in front of the housing body 60. The housing cover 62 has a substantially disc shape that extends around the axis of rotation O1. The housing cover 62 has a front surface 62a facing forward, a rear surface 62b facing backward and opposite the front surface 62a, and an outer circumferential surface 62c that is connected to the front surface 62a and the rear surface 62b and is located between the front surface 62a and the rear surface 62b.

[0021] Furthermore, the housing cover 62 has a second bearing section 66, a second insertion hole 61 and an outlet section 63.

[0022] The second bearing section 66 is formed integrally with approximately the center of the rear surface 62b and projects rearward from the rear surface 62b. The second insertion hole 61 is formed in a column shape that extends around the axis of rotation O1 and extends in the housing cover 62 in one direction of the axis of rotation O1. A rear end of the second insertion hole 61 is open at a rear end of the second bearing section 66, that is, at the rear end of the housing cover 62. Because the second insertion hole 61 is formed in this way, the second bearing section 66 has a cylindrical shape that extends around the axis of rotation O1.

[0023] On the other hand, a front end of the second insertion hole 61 is not open at the front end of the housing cover 62. Furthermore, a second plain bearing 52 is provided in the second insertion hole 61. The second plain bearing 52 is an example of the “bearing” of the present invention. An outer diameter of the second plain bearing 52 is defined as a first length L1, which is smaller than that of the second bearing section 66. The second plain bearing 52 has a cylindrical shape and is arranged in a front section of the second insertion hole 61. It should be noted that a ball bearing can be used as the “bearing” of the present invention.

[0024] The outlet section 63 is formed from an outlet communication port 69 and an outlet channel 67. The outlet communication port 69 is formed in the outer circumferential surface 62c. The outlet communication port 69 opens to an outer surface of the outer circumferential surface 62c in the radial direction of the housing cover 62. The outlet communication port 69 is connected to a capacitor (not shown) via a tube (not shown).

[0025] The outlet channel 67 is formed within the housing cover 62. The outlet channel 67 extends within the housing cover 62 in the radial direction of the housing cover 62. The outlet channel 67 is connected at one end to the outlet communication port 69 and at the other end to the second insertion hole 61. Consequently, the outlet channel 67 is in (fluid) communication with the outlet communication port 69 and the second insertion hole 61, thereby connecting the second insertion hole 61 to the outlet communication port 69.

[0026] In the housing 6, the housing cover 62 is arranged in front of the housing body 60; and the rear surface 62b of the housing cover 62 is in contact with the front end of the outer circumferential wall 60a of the housing body 60. In this state, the housing cover 62 is fastened to the housing body 60 by a plurality of bolts (not shown) from the side of the housing cover 62. Thus, in the housing 6, the housing body 60 and the housing cover 62 are integrated together.

[0027] Additionally, in the housing 6, the front of the housing body 60 is closed by the housing cover 62 to form an inlet chamber 65 within the housing body 60. The inlet chamber 65 is in (fluid) communication with the inlet communication port 68. Cooling gas is drawn into the inlet chamber 65 through the inlet communication port 68 from the outside of the housing 6. The cooling gas is an example of the "fluid" of the present invention. The cooling gas drawn into the inlet chamber 65 contains lubricating oil 18. The inlet chamber 65 is also in (fluid) communication with an inlet port 35b, which will be described later. Therefore, cooling gas in the inlet chamber 65 is drawn into an inlet space 30a, which will be described later, through the inlet port 35b.

[0028] The electric motor 10 is housed in the inlet chamber 65. The inlet chamber 65 also serves as a motor chamber in which the electric motor 10 is housed.

[0029] The electric motor 10 has a stator 17 and a rotor 11. The stator 17 has a cylindrical shape extending around the axis of rotation O1 and has a winding 17a. The stator 17 is fitted into an inner circumferential surface of the outer circumferential wall 60a, so that the stator 17 is attached to the housing body 60, and thus to the housing 6.

[0030] The rotor 11 has a cylindrical shape that extends around the axis of rotation O1 and is arranged inside the stator 17. Although a detailed illustration is omitted, the rotor 11 is formed from a plurality of permanent magnets belonging to the stator 17 and stacked (steel) laminations for mounting the permanent magnets.

[0031] The compression mechanism 14 is arranged in the housing 6. The compression mechanism 14 comprises a drive screw 30, a driven screw 40, a driven mechanism 20, and a first cover body 37. The first cover body 37 is an example of the "cover body" of the present invention.

[0032] The drive screw 30 is made of an aluminum alloy. The drive screw 30 comprises a drive screw end plate 31, a drive screw circumferential wall 32, a drive screw spiral body 33, and a closure body 35.

[0033] The drive worm end plate 31 extends in a substantially disc-like shape, perpendicular to the axis of rotation O1 and an output axis O2. The output axis O2 is eccentric with respect to the axis of rotation O1 and extends parallel to the axis of rotation O1. That is, the output axis O2 is parallel to the front-back direction. The drive worm end plate 31 has a front surface 311 facing the first cover body 37 and a rear surface 312 located opposite the front surface 311.

[0034] Additionally, the drive screw end plate 31 has a first recess 30b and an outlet port 30c. The first recess 30b is recessed from the front surface 311 in a substantially columnar shape. An inner diameter of the first recess 30b is equal to, or substantially equal to, an inner diameter of a second recess 37e, which will be described later, provided in the first cover body 37. The outlet port 30c is formed in the drive screw end plate 31 in a section within the first recess 30b and extends through the drive screw end plate 31 in the front-to-back direction. An outlet reed valve 57 and a retainer 58 are fastened to the drive screw end plate 31 in the first recess 30b by a fastening bolt 59. The outlet reed valve 57 is an example of the “outlet valve” of the present invention.

[0035] Opening the outlet reed valve 57 by elastic deformation allows cooling gas in the compression chamber 12 to be released into an outlet chamber 91 through the outlet port 30c. Closing the outlet reed valve 57 by elastic deformation prevents the cooling gas in the compression chamber 12 from being released into the outlet chamber 91 through the outlet port 30c. Furthermore, closing the outlet reed valve 57 prevents the cooling gas in the outlet chamber 91 from flowing into the compression chamber 12 through the outlet port 30c. The retainer 58 is able to adjust the degree of opening of the outlet reed valve 57. The compression chamber 12 and the outlet chamber 91 will be described in detail later.

[0036] The drive worm's circumferential wall 32 is formed integrally with the drive worm's end plate 31 and extends backwards, i.e., in the direction of the driven worm 40, from an outer circumferential edge of the drive worm's end plate 31 in a cylindrical shape. Thus, the drive worm's circumferential wall 32 extends parallel to the axis of rotation O1 and the output axis O2.

[0037] The drive screw spiral body 33 is formed integrally with the drive screw end plate 31 and is arranged within the drive screw circumferential wall 32. The drive screw spiral body 33 extends from the rear surface 312 of the drive screw end plate 31 towards the driven screw 40, parallel to the drive screw circumferential wall 32. As shown in Fig. As illustrated in Figure 5, the drive worm spiral body 33 has a spiral shape extending from a center of the drive worm end plate 31, which forms the center of the spiral, towards an outer circumferential section. An outer circumferential end of the drive worm spiral body 33 is connected to the drive worm circumferential wall 32. Fig. For the sake of clarity, the electric motor 10 is not shown in Figure 5. The same applies to the motors described later. Fig. 6 to 8 and 10.

[0038] As in Fig. As illustrated in Figure 1, the locking body 35 extends in a substantially disc-like shape, perpendicular to the axis of rotation O1 and the output axis O2. The locking body 35 has a front surface 351 facing forward and a rear surface 352 located opposite (to) the front surface 351.

[0039] The closure body 35 further comprises a first hub 35a and the inlet port 35b. The first hub 35a is integrally formed with the rear surface 352 at its center and projects backward along the axis of rotation O1 and the output axis O2. The first hub 35a has a cylindrical shape that extends around the axis of rotation O1. The inlet port 35b extends through the closure body 35 in the direction of the axis of rotation O1.

[0040] As in Fig. As illustrated in Figure 1, the closure body 35 has four rings 22 in its front surface 351. The rings 22 are arranged at equal intervals around the circumference of the closure body 35. Fig. 1 shows two of the four rings 22.

[0041] The first cover body 37 is a flattened tubular element and has an outer circumferential wall 37a, a front wall 37b, and a flange 37c. The outer circumferential wall 37a has a cylindrical shape extending around the axis of rotation O1. The outer diameter of the outer circumferential wall 37a is larger than that of the second sliding bearing 52. In particular, the outer diameter of the outer circumferential wall 37a is smaller than the inner diameter of the rotor 11 and the outer diameter of the drive worm end plate 31 by a length of the flange 37c projecting radially outward from the outer circumferential wall 37a.

[0042] Additionally, a return channel 370 is formed in the outer circumferential wall 37a. The return channel 370 is located in a front section of the outer circumferential wall 37a and extends through the outer circumferential wall 37a in a radial direction of the first cover body 37.

[0043] The front wall 37b is located at a front end of the first cover body 37. The front wall 37b extends in a substantially circular, flat, plate-like shape, perpendicular to the axis of rotation O1. An outer circumferential edge of the front wall 37b is connected to the front end of the outer circumferential wall 37a. Thus, the first cover body 37 has a second recess 37e, defined by an inner circumferential surface of the outer circumferential wall 37a and a rear surface of the front wall 37b, and extends in a substantially columnar shape in the direction of the axis of rotation O1.

[0044] The first cover body 37 is provided with a second hub 37d. The second hub 37d is an example of the "rotating shaft section" of the present invention. The second hub 37d is formed integrally with the front wall 37b in / at its center and projects forward from the front wall 37b in the direction of the axis of rotation O1 and the output axis O2.

[0045] As in Fig. As illustrated in Figure 2, the second hub 37d has a first diameter section 371, a second diameter section 372, and a third diameter section 373. The first diameter section 371 forms a rear section of the second hub 37d. The second diameter section 372 is located between the first diameter section 371 and the third diameter section 373, and forms a middle section of the second hub 37d. The third diameter section 373 forms a front section of the second hub 37d.

[0046] The first diameter section 371 has a largest outer diameter smaller than the first diameter section 371, the second diameter section 372, and the third diameter section 373. The second diameter section 372 has an outer diameter larger than that of the third diameter section 373. Consequently, the outer diameter of the second hub 37d decreases in three stages, that is, in the order of the first diameter section 371, the second diameter section 372, and the third diameter section 373. The outer diameter of the third diameter section 373 is approximately equal to the inner diameter of the second plain bearing 52.

[0047] Furthermore, an outlet communication section 38 is formed in the second hub 37d. The outlet communication section 38 allows cooling gas discharged into the outlet chamber 91 to flow to the outlet section 63. The outlet communication section 38 is formed from a connecting channel 38a and an outlet connecting hole 38b.

[0048] The connecting channel 38a extends through the second hub 37d and the front wall 37b in the direction of the axis of rotation O1. The connecting channel 38a has a columnar shape that extends around the axis of rotation O1. Consequently, the second hub 37d has a cylindrical shape that extends around the axis of rotation O1.

[0049] The outlet connection hole 38b is connected to the connection channel 38a and extends in the radial direction of the second hub 37d. The outlet connection hole 38b is open on an outer circumferential surface of the second hub 37d, in particular on an outer circumferential surface of the second diameter section 372.

[0050] The flange 37c is formed integrally with the outer circumferential wall 37a at its rear end. The flange 37c projects outwards in the radial direction of the first cover body 37 beyond the outer circumferential wall 37a. Consequently, the diameter of the flange 37c is larger than that of the outer circumferential wall 37a and is essentially the same as that of the drive screw end plate 31 of the drive screw 30. It should be noted that the flange 37c can be omitted.

[0051] In this compressor, the first cover body 37 is attached to the drive screw 30. Specifically, on the drive screw 30, the closure body 35 is in contact with the rear end of the drive screw's circumferential wall 32, with the front surface 351 of the closure body 35 facing the rear surface 312 of the drive screw's end plate 31. On the first cover body 37, the flange 37c is in contact with the outer circumferential wall 37a of the front surface 311, with the drive screw's end plate 31 and the flange 37c facing the drive screw's end plate 31.

[0052] In this state, the flange 37c of the first cover body 37, the drive screw end plate 31, the drive screw circumferential wall 32, and the closure body 35 are connected by a plurality of bolts 50 from the flange 37c side. Thus, in the case of the drive screw 30, the drive screw end plate 31, the drive screw circumferential wall 32, and the closure body 35 are integrated with one another. The first cover body 37 is integrated with the drive screw end plate 31 and thus with the drive screw 30. Fig. Figure 1 shows two of the multitude (of) bolts 50.

[0053] In this way, the first cover body 37 is attached to the drive screw 30, whereby the outlet chamber 91 defined by the first recess 30b and the second recess 37e is formed between the outer circumferential wall 37a and the front wall 37b of the first cover body 37 and the drive screw end plate 31.

[0054] The outlet chamber 91 is in (fluid) communication with the outlet port 30c, the return channel 370, and the connecting channel 38a. The outlet port 30c and the connecting channel 38a are in (fluid) communication with the outlet chamber 91 in the direction of the axis of rotation O1. Conversely, the return channel 370 is in (fluid) communication with the outlet chamber 91 in the radial direction of the first cover body 37, that is, in a direction perpendicular to the direction of the axis of rotation O1. The outlet port 30c, the return channel 370, and the connecting channel 38a each have a smaller diameter than that of the outlet chamber 91. The return channel 370 provides fluid communication between the outlet chamber 91 and the inlet chamber 65.

[0055] In this way, the first cover body 37 is received in the inlet chamber 65 and is rotatable as a single unit with the drive worm 30 about the axis of rotation O1. Furthermore, the first cover body 37 has the second hub 37d, which is fitted into the second plain bearing 52. Consequently, the first cover body 37 is supported by the second bearing section 66, i.e., the housing 6, via the second plain bearing 52 in such a way as to be rotatable about the axis of rotation O1.

[0056] Additionally, the drive screw 30 has the drive screw circumferential wall 32, which is inserted into and attached to the rotor 11. Consequently, the drive screw 30 is attached to and integrated with the rotor 11.

[0057] The driven screw 40 is also made of an aluminum alloy. The driven screw 40 is housed within the drive screw 30. The driven screw 40 has a driven screw end plate 41 and a driven screw spiral body 43.

[0058] The driven screw end plate 41 extends in a substantially disc-like shape, perpendicular to the axis of rotation O1 and the output axis O2. The driven screw 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 screw end plate 31 in the drive screw 30. The rear surface 412 is located opposite the front surface 411 and faces the front surface 351 of the closure body 35.

[0059] Furthermore, the driven worm end plate 41 has a receiving section 71. The receiving section 71 is recessed forward in a column shape from the rear surface 412 of the driven worm end plate 41. A bushing 53 is received in the receiving section 71. A driven pin 55 is inserted into the bushing 53. In particular, the driven pin 55 is inserted into the bushing 53 at a position that is eccentric to the center of the bushing 53. The driven pin 55 has a column shape and projects backward from the bushing 53 and thus from the driven worm end plate 41 in the direction of the first bearing section 64. The bushing 53 can be received in the receiving section 71 via a bearing such as a plain bearing.

[0060] Additionally, four anti-rotation pins 21 are attached to the rear surface 412. The anti-rotation pins 21 are each attached at a position facing outwards relative to the receiving section 71 and towards the ring 22 in the rear surface 412. The anti-rotation pins 21 each protrude backwards from the rear surface 412. Fig. Figure 1 shows two of the four anti-rotation pins 21.

[0061] The driven screw spiral body 43 is integrated with the driven screw end plate 41 and extends forward from the front surface 411 of the driven screw end plate 41 parallel to the axis of rotation O1 and the output axis O2. As shown in Fig. As illustrated in Figure 5, the driven worm spiral body 43 has a spiral shape extending from a center of the driven worm end plate 41 as a center of the spiral in the direction of an outer circumferential section.

[0062] The in Fig. Figure 1 illustrates the driven mechanism 20, which consists of four anti-rotation pins 21 and four rings 22. The number of anti-rotation pins 21 and the number of rings 22 can be as appropriate, as long as there are three or more of each.

[0063] In the compression mechanism 14, the drive screw spiral body 33 of the drive screw 30 and the driven screw spiral body 43 of the driven screw 40 are engaged with each other, with the driven screw 40 being received in the drive screw 30. Additionally, the anti-rotation pins 21 are inserted into their corresponding rings 22. Thus, the drive screw 30 and the driven screw 40 are assembled in a front-to-back direction. In particular, after the drive worm spiral body 33 and the driven worm spiral body 43 have engaged with each other and the anti-rotation pins 21 have been inserted into their associated rings 22, the first cover body 37, the drive worm end plate 31, the drive worm circumferential wall 32 and the locking body 35 are connected by the bolts 50 in the drive worm 30 and the first cover body 37.

[0064] After the drive worm 30 and the driven worm 40 are assembled, the first sliding bearing 51 is inserted into a first insertion hole 35d of the closure body 35 of the drive worm 30. Accordingly, the first hub 35a and thus the closure body 35 are rotatably mounted by the first bearing section 64 through / over the first sliding bearing 51.

[0065] Furthermore, in the first cover body 37, the second hub 37d of the first cover body 37 is inserted into the second insertion hole 61. Consequently, the third diameter section 373 of the second hub 37d is inserted into the second sliding bearing 52, as shown in Fig. Figure 2 illustrates this. The second plain bearing 52 is held by the second insertion hole 61, with the second plain bearing 52 being placed in contact with a step between the third diameter section 373 and the second diameter section 372, which is formed by the difference in the outer diameter. As a result, the second hub 37d, and thus the first cover body 37, are rotatably mounted by the second bearing section 66 through the second plain bearing 52. Accordingly, as shown in Fig. As illustrated in Figure 1, the drive worm 30 and the first cover body 37 are mounted by / from the housing 6 via both the first bearing section 64 and the second bearing section 66 in such a way as to be rotatable about the axis of rotation O1.

[0066] As a result, the second hub 37d is rotatable around the axis of rotation O1 within the second insertion hole 61.

[0067] As in Fig. As illustrated in Figure 2, the second diameter section 372 of the second hub 37d has a smaller diameter than that of the second insertion hole 61. Therefore, when the second hub 37d is supported by the second bearing section 66, the second diameter section 372 is spaced radially from an inner circumferential surface of the second insertion hole 61. Thus, the inner circumferential surface of the second insertion hole 61 and the second diameter section 372 are not in contact with each other. The second hub 37d is supported by the second bearing section 66 such that the outlet connection hole 38b faces an inner surface of the second insertion hole 61. Consequently, the outlet connection hole 38b is in fluid communication with the outlet channel 67 of the outlet section 63 through the second insertion hole 61.Accordingly, in this compressor, the outlet channel 67 and the outlet connection hole 38b, and thus the outlet section 63 and the outlet connection hole 38b, are in (fluid) communication with each other in the radial direction of the housing 6.

[0068] As in Fig. As illustrated in Figure 1, in the case of the driven worm 40, the driven pin 55 is inserted into the pin hole 4 of the first bearing section 64. Thus, the driven worm 40 is supported by the first bearing section 64 via the driven pin 55 in such a way that it can rotate about the output axis O2. That is to say, unlike the drive worm 30, the driven worm 40 is supported only by the first bearing section 64 of the housing 6 in such a way that it can rotate about the output axis O2.

[0069] In the compression mechanism 14, in which the drive screw 30 and the driven screw 40 are assembled in the front-back direction, two compression chambers 12 are formed between the drive screw spiral body 33 of the drive screw 30 and the driven screw spiral body 43 of the driven screw 40, as shown in Fig. 5 illustrates this. Additionally, as in Fig. Figure 1 illustrates that the drive screw 30 and the driven screw 40 are assembled in a front-to-back direction, with an inlet chamber 30a formed within the drive screw's circumferential wall 32. The inlet chamber 30a is capable of (fluid) communication with the inlet port 35b and with the compression chambers 12 when the compressor is / is being operated. The compression chambers 12 and the inlet chamber 30a are separated from the inlet chamber 65 by the drive screw 30 and the driven screw 40.

[0070] In the compressor with the configuration described above, low-temperature, low-pressure refrigerant gas, after passing through the evaporator, is drawn into the inlet chamber 65 through the inlet communication port 68, as indicated by a dashed arrow in Fig. 1 is displayed. When the electric motor 10 is / is operated to rotate the rotor 11, the drive worm 30 and the first cover body 37 rotate around the axis of rotation O1 in the inlet chamber 65. That is, the drive worm 30 and the first cover body 37 rotate integrally / together with the rotor 11. At this point, in the driven mechanism 20, the anti-rotation pins 21 slide on inner circumferential surfaces of their associated rings 22 to rotate the rings 22 around their centers relative to the anti-rotation pins 21. Thus, the driven mechanism 20 transmits a torque from the drive worm 30 to the driven worm 40.

[0071] As a result, the driven screw 40 is driven by the drive screw 30 and the driven mechanism 20 to rotate around the output axis O2. At this point, the driven mechanism 20 prevents the driven screw 40 from rotating. Accordingly, the driven screw 40 makes a revolution relative to the drive screw 30 around the output axis O2. In this compressor, the drive screw 30 and the driven screw 40 rotate in a direction of rotation R1, as shown in Fig. 5 and other drawings.

[0072] Furthermore, when the drive screw 30 is driven to rotate around the axis of rotation O1, the outlet connection hole 38b rotates relative to the outlet channel 67 in the direction of rotation R1, as shown in Fig. 9 and Fig. 11 illustrated.

[0073] A phase difference between the drive screw 30, which is driven to rotate around the axis of rotation O1, and the driven screw 40, which is driven to rotate around the output axis O2, is hereinafter referred to as a rotational phase between the drive screw 30 and the driven screw 40. As the rotational phase changes, the volume of each of the compression chambers 12 varies accordingly. As a result, as indicated by the dashed arrows in Fig. 1 is shown, the cooling gas in the inlet chamber 65 is drawn into the inlet space 30a through / over the inlet connection 35b and then into the compression chambers 12.

[0074] The cooling gas drawn into the compression chambers 12 is compressed within the compression chambers 12 as it flows from the outer circumferential sections of the drive screw spiral body 33 and the driven screw spiral body 43 towards their respective centers. The cooling gas, compressed to the outlet pressure in the compression chambers 12, is then discharged into the outlet chamber 91 from the outlet port 30c.

[0075] The refrigerant gas discharged into the outlet chamber 91 flows through / over the connecting channel 38a, the outlet connecting hole 38b, the second insertion hole 61, and the outlet channel 67; and is discharged through / over the outlet communication port 69 in the direction of the condenser. In this way, air conditioning is carried out by the vehicle's air conditioning system.

[0076] In this way, cooling gas is / is released into the outlet chamber 91 at / under high pressure, so that the pressure in the outlet chamber 91 is higher than that in the inlet chamber 65 and the inlet space 30a. In other words, the inlet chamber 65 and the inlet space 30a correspond to an intake pressure range, which is a section in the housing where the pressure is lower than in the outlet chamber 91.

[0077] In the compressor of the present invention, outlet pulsation inevitably occurs due to the discharge of the cooling gas from the compression chambers 12 into the outlet chamber 91. The compressor can effectively reduce outlet pulsation through a damping effect and a pulsation compensation function in the outlet chamber 91. In this description, the term "pulsation compensation function" refers to a function in which pulsations generated by the flow resistance of the fluid flowing from the outlet communication section to the outlet section serve to compensate for the outlet pulsations. These are explained in more detail below.

[0078] In the compressor of the present invention, the outlet chamber 91 is formed between the drive screw end plate 31 and the first cover body 37. An inner diameter of the outlet chamber 91 is defined as a second length L2 and is larger than the outer diameter of the second sliding bearing 52. A length of the outlet chamber 91 in the direction of the axis of rotation O1 is defined as a third length L3. Consequently, in this compressor, the volume of the outlet chamber 91 can be adequately controlled, and the damping effect in the outlet chamber 91 can be effectively exerted.

[0079] As described above, the cooling gas compressed in the compression chamber 12 flows through / over the outlet port 30c and is released into the outlet chamber 91. Since the outlet port 30c has a smaller diameter than that of the outlet chamber 91, the cooling gas compressed in the compression chamber 12 flows through / over the outlet port 30c and is then released into the outlet chamber 91, which is a space with a larger volume than that of the outlet port 30c.

[0080] Furthermore, the cooling gas flows through / over the connecting channel 38a and the like in the outlet chamber 91 and is discharged onto an outer surface of the outlet chamber 91, that is, onto the outer surface of the compressor. Here, the second hub 37d of the first cover body 37 is inserted into the second sliding bearing 52 and is supported by the second sliding bearing 52. Therefore, the second hub 37d, and thus the connecting channel 38a formed in the second hub 37d, has a smaller diameter than that of the second sliding bearing 52. That is, in this compressor, the inner diameter of the outlet chamber 91 is larger than the outer diameter of the second sliding bearing 52, so that the difference between the inner diameter of the outlet chamber 91 and the inner diameter of the connecting channel 38a is sufficiently large.

[0081] Therefore, the cooling gas compressed in the compression chamber 12 flows through / over the outlet port 30c, the outlet chamber 91, and the connecting channel 38a in that order. Thus, the cooling gas flows through a narrow space, a wide space, and another narrow space to be discharged onto the outside of the compressor. Accordingly, this compressor is designed to exert a sufficient damping effect in the outlet chamber 91.

[0082] Furthermore, since the length of the outlet chamber 91 in the direction of the axis of rotation O1 is the third length L3, the length of the outlet chamber 91 in the direction of the axis of rotation O1 can be suitably secured in this compressor. As a result, a low-frequency wavelength of the cooling gas compressed in the compression chamber 12 is suitably canceled out in the outlet chamber 91 of the compressor.

[0083] Accordingly, in this compressor, outlet pulsation, which occurs when cooling gas from the compression chamber 12 is released into the outlet chamber 91, can be suitably reduced by the damping effect in the outlet chamber 91.

[0084] The effect of a reduction of exhaust pulsation by the pulsation compensation function is described in more detail below, with reference to one of the two compression chambers 12.

[0085] As in Fig. As shown in Figure 3, the volume of the compression chamber 12 gradually increases from a minimum with a change in the rotation phase between the drive screw 30 and the driven screw 40. After the volume of the compression chamber 12 reaches a maximum, it gradually decreases with a change in the rotation phase between the drive screw 30 and the driven screw 40. During the process in which the volume of the compression chamber 12 increases from the minimum to the maximum, cooling gas is drawn into the compression chamber 12. That is, as described above, the cooling gas in the inlet chamber 65 is drawn into the compression chamber 12 from the inlet port 35b through the inlet space 30a.

[0086] In this compressor, when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X1, the drive screw 30, the driven screw 40 and the compression chamber 12 are in a Fig. The condition is illustrated in Figure 5. Furthermore, during the process in which the volume of the compression chamber 12 increases from minimum to maximum, the flow rate of the cooling gas drawn into the compression chamber 12 changes. When the rotation phase between the drive screw 30 and the driven screw 40 is at phase X1, the flow rate of the cooling gas drawn into the compression chamber 12 reaches its maximum. When the rotation phase between the drive screw 30 and the driven screw 40 is at phase X1, it is during the process in which the volume of the compression chamber 12 increases from minimum to maximum that the volume of the compression chamber 12 has not yet reached its maximum.

[0087] As in Fig. 3 shown, is achieved when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X2, which is larger than phase X1, the volume of the compression chamber 12 reaches its maximum (see Fig. 6) When the volume of the compression chamber 12 is at its maximum, the drive screw spiral body 33 and the driven screw spiral body 43 cause the compression chamber 12 and the inlet chamber 30a to no longer be in (fluid) communication with each other. Therefore, when the volume of the compression chamber 12 is at its maximum, the cooling gas is not drawn into the compression chamber 12; and the cooling gas is / will be trapped within the compression chamber 12.

[0088] As in Fig. As shown in Figure 3, when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X3, which is larger than phase X2, the volume of the compression chamber 12 is smaller than the maximum (see Figure 3). Fig. 7) Thus, the cooling gas in the compression chamber 12 begins to be / become compressed when the volume of the compression chamber 12 becomes smaller than the maximum.

[0089] As in Fig. As shown in Figure 4, when the rotation phase between the drive screw 30 and the driven screw 40 becomes greater than phase X3, the compression of the cooling gas in the compression chamber 12 progresses; and the pressure in the compression chamber 12 increases. Then, when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X4, as shown in Figure 4, the process begins. Fig. Figure 8 illustrates fluid communication between the compression chamber 12 and the outlet port 30c. However, at this point, the outlet reed valve 57 is still in a closed state.

[0090] Then, as in Fig. As shown in Figure 4, the rotation phase between the drive screw 30 and the driven screw 40 is at phase X5, and the compression of the cooling gas in the compression chamber 12 continues. As a result, the pressure in the compression chamber 12 exceeds the pressure in the outlet chamber 91; and thus the outlet reed valve 57 opens. Accordingly, the cooling gas from the compression chamber 12 begins to be released into the outlet chamber 91.

[0091] In this compressor, the outlet connection hole 38b is formed in the second hub 37d of the first cover body 37. Therefore, rotation of the first cover body 37 together with the rotation of the drive screw 30 causes the outlet connection hole 38b to rotate in the direction of rotation R1 about the axis of rotation O1 in the second insertion hole 61, as shown in Fig. 9 and Fig. Figure 11 illustrates this. Thus, the rotation of the first cover body 37 together with the rotation of the drive screw 30 changes a phase between the outlet channel 67 and the outlet connection hole 38b.

[0092] As a result of the phase change between the outlet channel 67 and the outlet connection hole 38b, the flow resistance (outlet-side flow resistance) of the refrigerant flowing from the outlet connection hole 38b to the outlet channel 67 changes in this compressor. Additionally, in this compressor, a pulsation occurs that differs from the outlet pulsation due to the flow resistance (hereinafter referred to as the "compensating pulsation"). If the flow resistance changes, the magnitude of the compensating pulsation also changes.

[0093] When the rotation phase between the drive screw 30 and the driven screw 40 is at phase X4, the outlet connection hole 38b is located in a position substantially directly facing the outlet channel 67, as shown in Fig. 9 illustrates this. Therefore, as shown by the dashed arrow in Fig. Figure 9 indicates that the cooling gas discharged from / into the connecting channel 38a from / into the outlet channel 67 flows essentially directly through / over the outlet connecting hole 38b. That is, if the phase between the outlet channel 67 and the outlet connecting hole 38b is in a Fig. In the state illustrated in Figure 9, the flow resistance is at a minimum. In other words, in this compressor, the outlet connection hole 38b is formed in the second hub 37d such that the flow resistance is at its minimum when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X4. As described above, when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X4, the outlet reed valve 57 is in the closed state. Therefore, the flow rate of the cooling gas discharged from the compression chamber 12 to the outlet chamber 91 is at its minimum, that is, zero. Consequently, in this compressor, when the flow rate of the cooling gas discharged from the compression chamber 12 to the outlet chamber 91 is at its minimum, the outlet channel 67 and the outlet connection hole 38b are in a phase that minimizes the flow resistance.It should be noted that the term "the flow rate of the fluid discharged from the compression chamber to the exhaust chamber is at its minimum" does not only include a case in which a small amount of fluid is discharged from the compression chamber to the exhaust chamber, but also a case in which the flow rate is zero.

[0094] If then, as in Fig. As shown in Figure 4, when the rotation phase between the drive screw 30 and the driven screw 40 is at phase X5, which is greater than phase X4, the pressure in the compression chamber 12 reaches the outlet pressure, thereby opening the outlet reed valve 57. As a result, cooling gas is discharged from the compression chamber 12 into the outlet chamber 91. At this point, the flow rate of the cooling gas discharged from the compression chamber 12 to the outlet chamber 91 reaches a maximum. When the rotation phase between the drive screw 30 and the driven screw 40 is at phase X5, the two compression chambers 12 are merged, as shown in Figure 4. Fig. 10 illustrated.

[0095] In this case, if the rotation phase between the drive screw 30 and the driven screw 40 is at phase X5, the outlet connection hole 38b is located at a position approximately opposite (from) the outlet channel 67 with respect to the direction of rotation R1 and transverse to the axis of rotation O1, as shown in Fig. 11 illustrates this. Therefore, as shown by the dashed arrow in Fig. Figure 11 illustrates that the cooling gas discharged from the outlet chamber 91 to the connecting channel 38a makes approximately half a turn in the direction of rotation R1 within the second insertion hole 61 of the outlet connecting hole 38b; and then flows through / over the outlet channel 67.

[0096] That is, if the phase between the outlet channel 67 and the outlet connection hole 38b is in a Fig. In the state illustrated in Figure 11, the flow resistance is at a maximum. Consequently, in this compressor, when the flow rate of the cooling gas to be discharged from the compression chamber 12 to the outlet chamber 91 is at its maximum, the outlet channel 67 and the outlet connection hole 38b are in a phase that maximizes the flow resistance.

[0097] In this compressor, when the outlet channel 67 and the outlet connection hole 38b are rotated in the direction of rotation R1 from their positions, in which the outlet channel 67 and the outlet connection hole 38b are generally directly opposite each other (see Fig. 9), are / become displaced, making it difficult for the cooling gas to flow from the outlet connection hole 38b into the outlet channel 67. Therefore, the flow resistance becomes greater than the minimum. Thus, in this compressor, the outlet channel 67 and the outlet connection hole 38b enter a phase in which the flow resistance increases as the flow rate of the cooling gas to be discharged from the compression chamber 12 to the outlet chamber 91 approaches a maximum. In particular, as the rotation phase between the drive screw 30 and the driven screw 40 approaches the rotation phase at which the flow rate of the cooling gas to be discharged into the outlet chamber 91 is at its maximum, the outlet channel 67 of the outlet section 63 and the outlet connection hole 38b enter a phase in which the flow resistance increases.

[0098] As described above, in this compressor, the phase change between the outlet channel 67 and the outlet connection hole 38b, and thus the phase change between the outlet section 63 and the outlet connection hole 38b, changes the flow resistance, and this change in flow resistance changes the magnitude of the compensating pulsation. As in Fig. As illustrated in Figure 12, in this compressor, the compensating pulsation has a waveform that is in the opposite phase to the waveform of the exhaust pulsation. Consequently, although exhaust pulsation inevitably occurs due to the discharge of the cooling gas from / into the exhaust chamber 91 from the compression chambers 12, the compensating pulsation acts to counteract the exhaust pulsation, thereby reducing the exhaust pulsation.

[0099] When the rotor 11 rotates at a low speed, that is, when the compression mechanism 14 operates at a low speed, the volumetric flow rate of the cooling gas flowing from / to the outlet connection hole 38b to the outlet channel 67 decreases. Consequently, the change in flow velocity resulting from the change in flow resistance is reduced; and thus, the pressure fluctuation caused by the change in flow velocity is also reduced. Therefore, when the compression mechanism 14 operates at a low speed, the pulsation reduction effect of the pulsation compensation function is small.

[0100] In this respect, even if the compression mechanism 14 operates at a low speed in the compressor, the exhaust pulsation can be adequately reduced in the exhaust chamber 91, where a sufficient volume is ensured. That is, if the compression mechanism 14 operates at a low speed, the amount of lubricating oil 18 that accumulates in the exhaust chamber 91 is small, as shown in Fig. Figure 1 illustrates that a large volume can be ensured in the outlet chamber 91 to reduce pulsation through damping action. Therefore, with this compressor, even when the compression mechanism 14 operates at a low speed, the damping effect effectively exerted in the outlet chamber 91 can adequately reduce the outlet pulsation.

[0101] On the other hand, if the compression mechanism 14 operates at a high speed, that is, if the rotor 11 rotates at a high speed, as in Fig. As illustrated in Figure 13, the amount of lubricating oil 18 that accumulates in the exhaust chamber 91 increases. This reduces the volume to decrease the pulsation caused by the damping effect in the exhaust chamber 91. Therefore, when the compression mechanism 14 operates at a high speed, the pulsation-reducing effect caused by the damping in the exhaust chamber 91 becomes smaller.

[0102] In this respect, when the compression mechanism 14 operates at a high speed, the pulsation compensation effect in this compressor is exerted more effectively. Therefore, even when the compression mechanism 14 operates at a high speed, the outlet pulsation can be adequately reduced by the pulsation compensation function in this compressor.

[0103] Furthermore, in this compressor, the outer diameter of the second plain bearing 52 is smaller than that of the outlet chamber 91. Even if the diameter of the outlet chamber 91 is increased, the diameter of the second plain bearing 52 remains the same. In other words, the second plain bearing 52 is designed so that its diameter does not exceed, and is equal to, the diameter of the outlet chamber 91. Consequently, any increase in energy losses in the second plain bearing 52 in this compressor can be suppressed. This can prevent a decrease in compressor efficiency. Moreover, even if the first cover body 37 rotates at a high speed in conjunction with the high-speed rotating rotor 11, the second plain bearing 52 can adequately support the first cover body 37, and subsequently the drive screw 30, above the first cover body 37.

[0104] Thus, the compressor of the first embodiment can achieve a high degree of smooth running while simultaneously suppressing a drop in efficiency.

[0105] In this compressor, the first cover body 37 is attached to the drive screw 30, and the outlet chamber 91 is formed between the drive screw end plate 31 and the first cover body 37. Therefore, when the drive screw 30 and the first cover body 37 rotate during operation of the compression mechanism 14, the centrifugal force generated by the rotation of the first cover body 37 acts on the fluid discharged into the outlet chamber 91. As a result, the cooling gas and the lubricating oil 18 can be suitably separated in the outlet chamber 91. The lubricating oil 18, separated from the cooling gas, tends to adhere to the inner circumferential surface of the outlet chamber 91 due to the centrifugal force of the first cover body 37 and the like, and also tends to remain in the outlet chamber 91 in a section extending outwards in the radial direction of the first cover body 37.Therefore, the lubricating oil 18 is less likely to be contained in the cooling gas to be discharged to the outside of the compressor via the outlet communication section 38 and the outlet section 63.

[0106] Additionally, the outlet chamber 91 is located in front of the compression chamber 12 transversely to the drive screw end plate 31; and the outlet chamber 91 is / is located close to / near the compression chamber 12, which allows the cooling gas and the lubricating oil 18 to be sufficiently separated in the outlet chamber 91.

[0107] The return channel 370 is formed in the outer circumferential wall 37a of the first cover body 37. Therefore, in this compressor, the centrifugal force acting on the first cover body 37 and the like, in particular the pressure difference between the outlet chamber 91 and the inlet chamber 65, in addition to the centrifugal force acting on the first cover body 37, causes the lubricating oil 18, together with a portion of the cooling gas, to flow from the outlet chamber 91 into the inlet chamber 65 through / via the return channel 370. In this way, the lubricating oil 18, which has flowed from the outlet chamber 91 into the inlet chamber 65, is recirculated into the inlet chamber 30a and thus into the compression chamber 12, together with the cooling gas drawn into the inlet port 35b.Accordingly, the inner surfaces of the compression chambers 12 can be lubricated with the lubricating oil 18 in the compressor, so that the drive screw end plate 31, the drive screw spiral body 33, the driven screw end plate 41, and the driven screw spiral body 43 are less susceptible to wear. Furthermore, the lubricating oil 18, which has flowed from the outlet chamber 91 into the inlet chamber 65, also lubricates the rotor 11, the first plain bearing 51, the second plain bearing 52, and the like.

[0108] Furthermore, the outlet chamber 91 is formed by the first recess 30b provided in the drive screw end plate 31 and the second recess 37e provided in the first cover body 37. This configuration makes it possible to easily change the size, shape, and position of the outlet chamber 91 by modifying the size, shape, and position of the first recess 30b and the second recess 37e according to their purpose. As a result, one degree of freedom in the design of the outlet chamber 91 in the compression mechanism 14 is increased.

[0109] Since the second hub 37d with the outlet communication section 38 is provided in the first cover body 37 attached to the drive screw 30, the outlet communication section 38 is designed in a simple way in the drive screw 30.

[0110] Additionally, the compressor features the outlet reed valve 57 provided in the drive screw 30; and the outlet reed valve 57 allows the cooling gas to be discharged from the compression chambers 12 into the outlet chamber 91, while preventing the cooling gas from flowing from the outlet chamber 91 into the compression chambers 12. Thus, the occurrence of pulsation in the compressor due to cooling gas flowing back from the outlet chamber 91 into the compression chambers 12 is effectively prevented. Furthermore, since the outlet connection hole 38b is formed in the second hub 37d, the outlet connection hole 38b is located downstream of the outlet reed valve 57 in a flow direction in which the cooling gas flows. Thus, in the compressor, the pressure fluctuation that occurs when the cooling gas flows from the outlet connection hole 38b to the outlet channel 67 facilitates the opening of the outlet lamellar valve 57.As a result, the outlet lamellar valve 57 can be opened and closed appropriately on this compressor.

[0111] In this compressor, the outlet section 63 has the outlet channel 67 and the outlet communication port 69; and the outlet channel 67 and the outlet connection port 38b are in (fluid) communication with each other in the radial direction of the housing 6. According to this configuration, the entire compressor, including the housing 6, can be reduced in size in the direction of the axis of rotation O1 compared to a configuration in which the outlet channel 67 and the outlet connection port 38b are in (fluid) communication with each other in the direction of the axis of rotation O1. Thus, in this compressor, the length of the outlet chamber 91 in the direction of the axis of rotation O1 is set to the third length L3; and the outlet chamber 91 is designed to be long in the direction of the axis of rotation O1, thereby increasing its volume. This configuration prevents excessive enlargement of the housing 6 as a whole in any axial direction. Second embodiment

[0112] As in Fig. As illustrated in Figure 14, a compressor of the second embodiment has a housing 6 formed from a housing body 60 and a housing cover 70. Additionally, in the compressor of the second embodiment, the compression mechanism 14 has a second cover body 81 instead of the first cover body 37. The second cover body 81 is an example of the “cover body” of the present invention.

[0113] The housing cover 70 is also made of an aluminum alloy. The housing cover 70 is arranged in front of the housing body 60. The housing cover 70 has a substantially disc shape that extends around the axis of rotation O1. The housing cover 70 has a front surface 70a facing forward, a rear surface 70b facing backward and opposite the front surface 70a, and an outer circumferential surface 70c that is connected to the front surface 70a and the rear surface 70b and is located between the front surface 70a and the rear surface 70b. The housing cover 70 is attached to the outer circumferential wall 60a of the housing body 60 in the same way as the housing cover 62 of the compressor of the first embodiment.

[0114] The housing cover 70 has a second insertion hole 72 and an outlet communication port 73. The outlet communication port 73 is an example of the "outlet section" of the present invention.

[0115] The second insertion hole 72 extends in a column shape with the axis of rotation O1 in the center; and extends in the housing cover 70 in the direction of the axis of rotation O1. A rear end of the second insertion hole 72 is open at the rear surface 70b. The second sliding bearing 52 is provided in the second insertion hole 72, similar to the compressor of the first embodiment.

[0116] The outlet communication port 73 extends through the housing cover 70 in the direction of the axis of rotation O1. Thus, the outlet communication port 73 has a front end that is open at the front surface 70a, and a rear end that is in (fluid) communication with the second insertion hole 72. As shown in Fig. As illustrated in Figures 15A to 15D, the outlet communication port 73 is formed in a column shape and is eccentric with respect to the axis of rotation O1. That is, the outlet communication port 73 is formed in the housing cover 70 at a position eccentric with respect to the axis of rotation O1. The outlet communication port 73 is connected to a capacitor (not shown) via a tube (not shown).

[0117] As in Fig. As illustrated in Figure 14, the second cover body 81 has the same configuration as the first cover body 37 of the compressor of the first embodiment, except that the second cover body 81 has a second hub 81d instead of the second hub 37d of the compressor of the first embodiment. The second hub 81d is an example of the “rotary shaft section” of the present invention.

[0118] That is, the second cover body 81 is a flattened tube element; and has an outer circumferential wall 81a, a front wall 81b, and a flange 81c, similar to the first cover body 37 of the compressor of the first embodiment. Additionally, a return channel 810 similar to the return channel 370 of the compressor of the first embodiment is formed in the outer circumferential wall 81a. Thus, the second cover body 81 has a second recess 81e, which is defined by an inner circumferential surface of the outer circumferential wall 81a and a rear surface of the front wall 81b, and extends in a substantially columnar shape in the direction of the axis of rotation O1.

[0119] The drive screw end plate 31 of the second embodiment has the same configuration as that of the drive screw end plate 31 of the compressor of the first embodiment. In other words, the drive screw end plate 31 has a first recess 30b, which extends backwards in a substantially columnar shape from the front surface 311 of the drive screw end plate 31; and the outlet vane valve 57 and the like are mounted in the first recess 30b.

[0120] An outlet chamber 92, defined by the first recess 30b and the second recess 81e, is formed between the drive screw end plate 31 and the second cover body 81. The second length L2 and the third length L3 of the outlet chamber 92 are set to be the same as those of the outlet chamber 91 of the compressor of the first embodiment.

[0121] The second hub 81d is formed integrally with the front wall 81b at its center; and projects forward from the front wall 81b in the direction of the axis of rotation O1 and the output axis O2. Consequently, the center of the second hub 81d is coaxial with the axis of rotation O1.

[0122] Additionally, the second cover body 81 has a connecting channel 82. The connecting channel 82 is an example of the "outlet communication section" of the present invention. The connecting channel 82 extends through the front wall 81b of the second cover body 81, including the inside of the second hub 81d, in the direction of the axis of rotation O1. As shown in Fig. As illustrated in Figures 14 and 15A to 15D, the connecting channel 82 is columnar in shape and eccentric with respect to the axis of rotation O1. That is, the connecting channel 82 is formed in the second cover body 81 at a position eccentric with respect to the axis of rotation O1. The connecting channel 82 has a smaller diameter than that of the outlet communication port 73. Fig. For the sake of simplicity, figures 15A to 15D illustrate the outlet communication port 73 and the connection channel 82 in a simplified form; and the second hub 81d and the like are not illustrated.

[0123] As in Fig. As illustrated in Figure 14, in this compressor, similar to the compressor of the first embodiment, the second cover body 81, the drive screw end plate 31, the drive screw circumferential wall 32, and the closure body 35 are connected by a plurality of bolts 50. Accordingly, the second cover body 81 covers the drive screw end plate 31 from the front. In this way, the connecting channel 82 is in (fluid) communication with the outlet chamber 92 from the front. Furthermore, the connecting channel 82 is located downstream of the outlet reed valve 57 in the direction of flow of the cooling gas.

[0124] In this compressor, the second hub 81d is inserted into the second insertion hole 72. Thus, the second hub 81d is rotatably mounted within the second insertion hole 72 by the second sliding bearing 52. The outlet communication port 73 and the connecting channel 82 are in (fluid) communication with each other in the direction of the axis of rotation O1. It should be noted that other components of the compressor of the second embodiment are the same as those of the compressor of the first embodiment; and components of the second embodiment that correspond to those of the first embodiment are designated with the same reference numerals, and a detailed description of the configurations is omitted.

[0125] In this compressor, the cooling gas compressed in the compression chambers 12 is / is released into the outlet chamber 92 through / via the outlet port 30c.

[0126] The cooling gas released into the outlet chamber 92 flows through the connecting channel 82; and is / is released from the outlet communication port 73 in the direction of the condenser.

[0127] In this compressor, both the outlet communication port 73 and the connecting channel 82 are eccentric with respect to the axis of rotation O1, as shown in Fig. Figures 15A to 15D illustrate this. Therefore, in this compressor, a phase changes between the outlet communication port 73 and the connection channel 82 while the drive screw 30 completes one revolution in the direction of rotation R1, as shown in Fig. Illustrated in sections 15A to 15D.

[0128] This means that in this compressor, when the rotation angle of the drive screw is 30 zero degrees, the outlet communication port 73 and the connection channel 82 are connected to a Fig. Phase 15A illustrated. When the drive screw 30 rotates approximately 90 degrees in the direction of rotation R1 from the in Fig. In the position illustrated in 15A, the outlet communication port 73 and the connection channel 82 reach a position that is Fig. Phase 15B illustrated. When the drive screw 30 rotates approximately 90 degrees in the direction of rotation R1 from the position shown in Figure 15B, the following occurs: Fig. 15B illustrated position rotates (when the drive screw 30 rotates approximately 180° in the direction of rotation R1 from the position shown in Fig. (15A illustrated position rotates), the outlet communication port 73 and the connection channel 82 reach a point in Fig. Phase 15C illustrated. When the drive screw 30 rotates approximately 90 degrees in the direction of rotation R1 from the position shown in Fig. 15C illustrated position rotates (when the drive screw 30 rotates approximately 270° in the direction of rotation R1 from the position shown in Fig. (15A illustrated position rotates), the outlet communication port 73 and the connection channel 82 reach a point in Fig. 15D illustrated phase.

[0129] Accordingly, if a communication surface between the outlet communication port 73 and the connecting channel 82 changes during one revolution of the drive screw 30, the flow resistance of the cooling gas flowing from the connecting channel 82 to the outlet communication port 73 in the compressor changes.

[0130] In particular, if the (fluid) communication area / connection area between the outlet communication port 73 and the connection channel 82 is / becomes increased, the flow resistance is / will be reduced; and if the communication area between the outlet communication port 73 and the connection channel 82 is / will be reduced, the flow resistance is / will be increased. Therefore, in the compressor, if the phase between the outlet communication port 73 and the connection channel 82 in the Fig. In the state illustrated in Figure 15A, the communication area between the outlet communication port 73 and the connection channel 82 is maximized; and the flow resistance is minimized. On the other hand, if the phase between the outlet communication port 73 and the connection channel 82 is in the state illustrated in Figure 15A, the communication area between the outlet communication port 73 and the connection channel 82 is maximized; and the flow resistance is minimized. Fig. In the illustrated state of 15C, the communication area between the outlet communication port 73 and the connection channel 82 is minimized; and the flow resistance is maximized.

[0131] In this compressor, when the flow rate of the cooling gas discharged from the compression chamber 12 into the outlet chamber 92 is at a minimum, the outlet communication port 73 and the connecting channel 82 are in a phase that minimizes the flow resistance (see Fig. 15A). Then, when the flow rate of the cooling gas discharged from the compression chamber 12 into the outlet chamber 92 is at a maximum, the outlet communication port 73 and the connecting channel 82 are in a phase that maximizes the flow resistance (see Fig. 15C).

[0132] As a result, in the compressor of the second embodiment, although outlet pulsation inevitably occurs due to the release of the cooling gas from the compression chambers 12 to / into the outlet chamber 92, the outlet pulsation is reduced by the compensating pulsation effect, similar to the compressor of the first embodiment.

[0133] Additionally, since the outlet communication port 73 and the connecting channel 82 are in (fluid) communication with each other in the direction of the axis of rotation O1, the entire compressor, including the housing 6, can be reduced in size radially compared to a configuration in which the outlet communication port 73 and the connecting channel 82 are in (fluid) communication with each other radially along the housing 6. The remaining operating processes of the compressor of the second embodiment are the same as those of the compressor of the first embodiment. Third embodiment

[0134] As in Fig. As illustrated in Figure 16, a compressor of the third embodiment has a housing 6 formed from a housing body 60 and a housing cover 75. Additionally, in the compressor of the third embodiment, the compression mechanism 14 has a third cover body 83 instead of the first cover body 37 of the first embodiment. The third cover body 83 is an example of the “cover body” of the present invention.

[0135] The housing cover 75 is formed from a body element 75a and a retaining element 75b. The body element 75a is made of an aluminum alloy. The body element 75a has a substantially disc-like shape extending around the axis of rotation O1, similar to the housing cover 70 of the compressor of the second embodiment. The body element 75a has a front surface 751 facing forward, a rear surface 752 facing backward and located opposite the front surface 751, and an outer circumferential surface 753 connected to the front surface 751 and the rear surface 752 and located between the front surface 751 and the rear surface 752.

[0136] The body element 75a is attached to the outer circumferential wall 60a of the housing body 60 in the same manner as the housing cover 62 of the compressor of the first embodiment. Accordingly, the housing body 60 and the housing cover 75 are attached to each other in the compressor of the third embodiment.

[0137] The body element 75a has a second insertion hole 76 and a first communication port 77a. The second insertion hole 76 is formed in a column shape that extends around the axis of rotation O1 and into the body element 75a in the direction of the axis of rotation O1. A rear end of the second insertion hole 76 is open at the rear surface 752. The second insertion hole 76 has a larger diameter than the second insertion hole 72 of the compressor of the second embodiment.

[0138] The first communication port 77a extends through the body element 75a in the direction of the axis of rotation O1. Thus, the first communication port 77a has a front end that is open at the front surface 751 and a rear end that is in (fluid) communication with the second insertion hole 76. Although a detailed description is omitted, the first communication port 77a is columnar in shape and eccentric with respect to the axis of rotation O1, similar to the outlet communication port 73 of the compressor of the second embodiment. That is, the first communication port 77a is formed in the body element 75a at a position eccentric with respect to the axis of rotation O1.

[0139] The retaining element 75b is made of plastic. The retaining element 75b has a generally flattened, tubular shape. A second communication port 77b is formed in a front section of the retaining element 75b. The second communication port 77b extends through the front section of the retaining element 75b in the direction of the axis of rotation O1. The second communication port 77b extends in a columnar shape that is coaxial with the first communication port 77a and has the same diameter. That is, the second communication port 77b is formed in the front section of the retaining element 75b at a position eccentric with respect to the axis of rotation O1.

[0140] The retaining element 75b is received in the second insertion hole 76. The retaining element 75b is received in the second insertion hole 76 in a non-rotatable state. Thus, neither the body element 75a nor the retaining element 75b can rotate within the housing cover 75. Furthermore, with the retaining element 75b received in the second insertion hole 76, the second communication port 77b is located behind the first communication port 77a and is in (fluid) communication with the first communication port 77a. In this way, the first communication port 77a and the second communication port 77b form the outlet communication port 77. That is, the outlet communication port 77 is formed in the housing cover 75 at an eccentric position with respect to the axis of rotation O1. The outlet communication port 77 is an example of the "outlet section" of the present invention.

[0141] Furthermore, a radial ball bearing 78 is provided within the retaining element 75b. The radial ball bearing 78 is an example of the "bearing" of the present invention. The retaining element 75b holds the radial ball bearing 78 while it is received in the second insertion hole 76. An outer diameter of the radial ball bearing 78 is defined as a fourth length L4. The fourth length L4 of the radial ball bearing 78 is longer than the first length L1 of the second plain bearing 52 of the compressor of the second embodiment. In addition, sealing rings 79a, 79b are provided on the outer circumferential surface of the retaining element 75b. The sealing rings 79a, 79b seal a gap between the outer circumferential surface of the retaining element 75b and an inner circumferential surface of the second insertion hole 76. Instead of the radial ball bearing 78, a plain bearing can be provided within the retaining element 75b.Furthermore, the retaining element 75b can be made of synthetic rubber or metal or the like with less stiffness than the body element 75a (manufactured).

[0142] The third cover body 83 has the same configuration as the second cover body 81 of the compressor of the second embodiment. That is, the third cover body 83 is a flattened tube element, has an outer circumferential wall 83a, a front wall 83b and a flange (not shown), similar to the second cover body 81 of the compressor of the second embodiment, and has a return channel 830 formed in the outer circumferential wall 83a. In addition, the third cover body 83 has a second recess 83e, which is defined by an inner circumferential surface of the outer circumferential wall 83a and a rear surface of the front wall 83b, and extends in an essentially columnar shape in the direction of the axis of rotation O1.

[0143] An outlet chamber 93, defined by the first recess (not shown) and the second recess 83e, is formed between the drive screw end plate (not shown) and the third cover body 83. The second length L2 and the third length L3 of the outlet chamber 93 are set to be the same as those of the outlet chamber 92 of the compressor of the second embodiment. The second length L2, which is the length of the inner diameter of the outlet chamber 93, is longer than the fourth length L4, which is a length of the outer diameter of the radial ball bearing 78.

[0144] Furthermore, the third cover body 83 has a second hub 83d, similar to the second cover body 81 of the compressor of the second embodiment. The second hub 83d is an example of the "rotating shaft section" of the present invention. The second hub 83d is formed integrally with the front wall 83b at its center and projects forward from the front wall 83b in the direction of the axis of rotation O1 and the output axis O2. Consequently, the center of the second hub 83d is coaxial with the axis of rotation O1. The forward projection of the second hub 83d is smaller than that of the second hub 81d of the compressor of the second embodiment.

[0145] The third cover body 83 has a connecting channel 84, similar to the second cover body 81 of the compressor of the second embodiment. The connecting channel 84 is an example of the "outlet communication section" of the present invention. The connecting channel 84 extends through the front wall 83b of the third cover body 83, including the inside of the second hub 83d, in the direction of the axis of rotation O1. The connecting channel 84 is formed in a column shape and is eccentric with respect to the axis of rotation O1, similar to the connecting channel 82 of the compressor of the second embodiment. That is, the connecting channel 84 is formed in the third cover body 83 at a position eccentric with respect to the axis of rotation O1. In addition, the connecting channel 84 has a smaller diameter than that of the outlet communication port 77.

[0146] The third cover body 83 is connected to the drive screw end plate (not shown) by a plurality of bolts (not shown), similar to the second cover body 81 of the compressor of the second embodiment. Thus, the connecting channel 84 is in (fluid) communication with the outlet chamber 93 from the front. Furthermore, the connecting channel 84 is located downstream of the outlet reed valve (not shown) in the direction of flow of the cooling gas.

[0147] In this compressor, the second hub 83d is inserted through an inner surface of the radial ball bearing 78. Consequently, the second hub 83d is rotatably mounted within the retaining element 75b and further within the second insertion hole 76 of the body element 75a. The outlet communication port 77 and the connecting channel 84 are in (fluid) communication with each other in the direction of the axis of rotation O1. Other configurations of this compressor are the same as those of the compressor of the second embodiment.

[0148] In this compressor, both the outlet communication port 77 and the connecting channel 84 are eccentric with respect to the axis of rotation O1. Therefore, similar to the compressor of the second embodiment, a phase changes between the outlet communication port 77 and the connecting channel 84 while the drive screw 30 completes one revolution in the direction of rotation R1 (see Fig. 15A to 15D). In this way, with this compressor, similar to the compressor of the second embodiment, the outlet pulsation can be reduced by the pulsation compensation function.

[0149] In this compressor, when the refrigerant gas is compressed in the compression chamber (not shown), vibrations inevitably occur in the drive screw 30 and other components. In this regard, the retaining element 75b, which is made of resin and provided in the second insertion hole 76, holds the radial ball bearing 78. Consequently, the retaining element 75b can suppress the transmission of vibrations from the drive screw 30 to the body element 75a via the second hub 83d and the radial ball bearing 78. This allows vibrations of the housing cover 75, and thus of the housing 6, to be largely suppressed during operation of the compressor. The remaining operating procedures of the compressor of the third embodiment are the same as those of the compressor of the second embodiment. Fourth embodiment

[0150] As in Fig. As illustrated in Figure 17, in a compressor of the fourth embodiment, the compression mechanism 14 has a fourth cover body 85 instead of the first cover body 37 of the compressor of the first embodiment. The fourth cover body 85 is an example of the “cover body” of the present invention. In the compressor of the fourth embodiment, the drive screw 30 has a drive screw end plate 310 instead of the drive screw end plate 31 of the compressor of the first embodiment.

[0151] The length of the drive screw end plate 310 in the direction of the axis of rotation O1 is shorter than that of the drive screw end plate 31 of the compressor of the first embodiment. Furthermore, a front surface 311 of the drive screw end plate 310 does not have a recess corresponding to the first recess 30b of the drive screw end plate 31. Otherwise, the drive screw end plate 310 has the same configuration as the drive screw end plate 31 of the compressor of the first embodiment.

[0152] The fourth cover body 85 has the same configuration as the first cover body 37 of the compressor of the first embodiment, except that the fourth cover body 85 has an outer circumferential wall 85a instead of the outer circumferential wall 37a of the compressor of the first embodiment. The outer circumferential wall 85a of the fourth cover body 85 is longer than the outer circumferential wall 37a of the compressor of the first embodiment in the direction of the axis of rotation O1.

[0153] That is, the fourth cover body 85 is a flattened tubular element; and has an outer circumferential wall 85a, a front wall 85b, and a flange 85c, similar to the first cover body 37 of the compressor of the first embodiment. Additionally, a return channel 850 similar to the return channel 370 of the compressor of the first embodiment is formed in the outer circumferential wall 85a. Thus, the fourth cover body 85 has a second recess 85e, defined by an inner circumferential surface of the outer circumferential wall 85a and a rear surface of the front wall 85b, and extends in a substantially columnar shape in the direction of the axis of rotation O1.

[0154] An outlet chamber 94, defined by the front surface 311 of the drive screw end plate 310 and the second recess 85e, is formed between the drive screw end plate 310 and the fourth cover body 85. The second length L2 and the third length L3 of the outlet chamber 94 are set to be the same as those of the outlet chamber 91 of the compressor of the first embodiment.

[0155] Furthermore, the fourth cover body 85 has a second hub 85d, similar to the first cover body 37 of the compressor of the first embodiment. The second hub 85d is an example of the "rotating shaft section" of the present invention. The fourth cover body 85 has an outlet communication section 86, which is formed from a connecting channel 86a and an outlet connecting hole 86b, similar to the first cover body 37 of the compressor of the first embodiment.

[0156] In the compressor of the fourth embodiment, the front surface 311 of the drive screw end plate 310 is designed as a flat surface, which allows for easy manufacturing of the drive screw 30.

[0157] Other configurations and effects of this compressor are the same as those of the compressor of the first embodiment. Fifth embodiment

[0158] As in Fig. As illustrated in Figure 18, in a compressor of the fifth embodiment, the compression mechanism 14 has a fifth cover body 87 instead of the first cover body 37 of the compressor of the first embodiment. The fifth cover body 87 is an example of the “cover body” of the present invention. In the compressor of the fifth embodiment, the drive screw 30 has a drive screw end plate 320 instead of the drive screw end plate 31 of the compressor of the first embodiment.

[0159] The length of the drive screw end plate 320 in the direction of the axis of rotation O1 is longer than that of the drive screw end plate 31 of the compressor of the first embodiment. Furthermore, a first recess 30d formed in the front surface 311 of the drive screw end plate 320 in the direction of the axis of rotation O1 is longer than that of the first recess 30b of the compressor of the first embodiment. Otherwise, the drive screw end plate 320 of the fifth embodiment has the same configuration as the drive screw end plate 31 of the compressor of the first embodiment.

[0160] The fifth cover body 87 has a cover main body 87a and a second hub 87b. The second hub 87b is an example of the "rotating shaft section" of the present invention. The cover main body 87a extends in a substantially disc shape, perpendicular to the axis of rotation O1 and the output axis O2. The diameter of the cover main body 87a is substantially the same as that of the drive screw end plate 320. The second hub 87b is formed integrally with the cover main body 87a and projects forward from the cover main body 87a in the direction of the axis of rotation O1 and the output axis O2. Other configurations of the second hub 87b are the same as those of the second hub 37d of the compressor of the first embodiment.

[0161] The fifth cover body 87 has an outlet communication section 88, which is formed from a connecting channel 88a and an outlet connecting hole 88b, similar to the first cover body 37 of the compressor of the first embodiment.

[0162] In the drive screw 30, the fifth cover body 87, the drive screw end plate 320, the drive screw circumferential wall 32, and the closure body 35 are connected by a plurality of bolts (or screws) 50, with the main cover body 87a of the fifth cover body 87 being in contact with the front surface 311 of the drive screw end plate 320. Accordingly, the drive screw end plate 320, the drive screw circumferential wall 32, the closure body 35, and the fifth cover body 87 are jointly integrated into the drive screw 30.

[0163] In this way, an outlet chamber 95, defined by the first recess 30d and the rear surface of the main cover body 87a, is formed between the drive screw end plate 320 and the fifth cover body 87. A fifth length L5, which is the length of the inner diameter of this outlet chamber 95, is longer than the second length L2, which is the length of the inner diameter of the outlet chamber 91 of the compressor of the first embodiment; and a sixth length L6, which is the length of the outlet chamber 95 in the direction of the axis of rotation O1, is shorter than the third length L3 of the outlet chamber 91 of the compressor of the first embodiment. It is noted that the fifth length L5, which is the length of the inner diameter of the outlet chamber 95, may be equal to or shorter than the second length L2.Furthermore, the sixth length L6, which is the length of the outlet chamber 95 in the direction of the axis of rotation O1, can be set to the third length L3 or can be longer than the third length L3.

[0164] In the fifth cover body 87, the main cover body 87a covers the first recess 30d of the drive screw end plate 320 from the front. Thus, the outlet communication section 88 is in (fluid) communication from the front with the outlet chamber 95 defined by the first recess 30d.

[0165] In the compressor, the main cover body 87a does not have an outer circumferential wall or a flange, so the fifth cover body 87 can be easily manufactured. Furthermore, since the sixth length L6 of the outlet chamber 95 is shorter, the length of the housing 6 along the axis can be made shorter than that of the compressor in the first embodiment.

[0166] Other configurations and effects of this compressor are the same as those of the compressor of the first embodiment.

[0167] Although the present invention has been described above on the basis of the first to fifth embodiments, the present invention is not limited to the first to fifth embodiments described above and can be modified as appropriate within the scope of the present invention.

[0168] In the compressor of the first embodiment, the drive screw 30 and the driven screw 40 are assembled, with the driven screw 40 being housed within the drive screw 30. However, the present invention is not limited to this; the drive screw 30 and the driven screw 40 can also be assembled with the driven screw 40 located outside the drive screw 30. In this case, the driven screw end plate 41 and the "cover body" of the present invention can be attached to one another. The same applies to the compressors according to the second to fifth embodiments.

[0169] In the compressor of the first embodiment, the second hub 37d is defined as the "rotating shaft section" of the present invention. The second hub 37d is rotatably mounted by the second bearing section 66, the second hub 37d being inserted through the second insertion hole 61. However, the present invention is not limited to this. The second hub 37d is rotatably mounted by the second bearing section 66, the second bearing section 66 being inserted into an interior of the second hub 37d. The same applies to the compressors according to the second to fifth embodiments.

[0170] In the compressor of the second embodiment, the outlet communication port 73 is designed in a column shape and is eccentric with respect to the axis of rotation O1. However, the shape of the outlet communication port 73 is not limited to this; it can also have a different shape. The same applies to the outlet communication port 77 of the compressor of the third embodiment.

[0171] Furthermore, in the compressor of the first embodiment, the drive screw 30 is integrated with the rotor 11 by attaching the drive screw circumferential wall 32 to the rotor 11, although the configuration is not limited to this. The first cover body 37 and the rotor 11 can be integrated with each other by attaching the rotor 11 to the outer circumferential wall 37a. The same applies to the compressors of the second to fourth embodiments; and the rotor 11 can be attached to the "cover body" of the present invention.

[0172] The compressor of the first embodiment can have a configuration in which the drive screw 30 is spaced apart from the rotor 11 in the direction of the axis of rotation O1 by connecting the drive screw 30 to the rotor 11 via a shaft, so that drive energy is / is transmitted. The same applies to the compressors according to the second to fifth embodiments.

[0173] In the compressor of the first embodiment, the driven mechanism 20 is formed from the anti-rotation pins 21 and the rings 22. However, the configuration is not limited to this, and the driven mechanism 20 can be formed by a pin-ring-pin mechanism in which two pins slide onto an inner circumferential surface of a free ring, a pin-and-pin mechanism in which the outer circumferential surfaces of two pins slide against each other, a mechanism using an Oldham coupling, or the like. The same applies to the compressors according to the second to fifth embodiments. This description contains the following invention. (Additional Note 1)

[0174] A synchronous spiral compressor with: a housing with an outlet section through which fluid is / is discharged to an outside; and a compression mechanism located in the housing; where the compression mechanism has / features: a compression chamber in which fluid is / is compressed while a volume of the compression chamber is / is reduced; an outlet chamber that is in (fluid) communication with the compression chamber and into which the fluid compressed in the compression chamber is / is released; and a rotating shaft section which is supported by the housing via a bearing in such a way as to be rotatable around an axis of rotation; wherein the compression mechanism comprises a drive screw and a driven screw, wherein the drive worm is configured to be rotated by a drive mechanism, wherein the drive worm has a drive worm end plate and a drive worm spiral body which is integrally formed with the drive worm end plate and projects in a spiral shape towards the driven worm; and wherein the driven screw faces the drive screw and is arranged to be rotated by the drive screw and a driven mechanism at an eccentric position with respect to the drive screw in order to form the compression chamber between the drive screw and the driven screw, wherein the driven worm has a driven worm end plate and a driven worm spiral body which is formed integrally with the driven worm end plate and projects in a spiral shape towards the drive worm; wherein characterized in that the outlet chamber has a larger diameter than the outer diameter of the bearing, The rotating shaft section has an outlet communication section through which the fluid released into the outlet chamber flows to the outlet section; a phase change (or phase shift) between the outlet section and the outlet communication section, with rotation of the rotating shaft section, changes the flow resistance for the fluid flowing from / to the outlet communication section; and The outlet section and the outlet communication section reach a phase in which the flow resistance increases while / as the flow rate of the fluid to be discharged from the compression chamber to the outlet chamber approaches a maximum. (Additional note 2)

[0175] The synchronous spiral compressor according to supplementary note 1, wherein the compression mechanism comprises a cover body that is attached to the drive screw or the driven screw and is provided with the rotating shaft section; and the outlet chamber is formed between the cover body and the drive screw end plate of the drive screw, to which the cover body is attached, or between the cover body and the driven screw end plate of the driven screw, to which the cover body is attached. (Additional note 3)

[0176] The synchronous spiral compressor according to supplementary note 1 or 2, wherein Lubricating oil is / is released into the exhaust chamber together with the fluid compressed in the compression chamber; and the outlet chamber and a section in the housing where the pressure is lower than in the outlet chamber are connected via a return channel through which the lubricating oil is recirculated in the outlet chamber. (Additional note 4)

[0177] The synchronous spiral compressor according to one of the supplementary notes 1 to 3, wherein The outlet section and the outlet communication section are in (fluid) communication with each other in a radial direction of the housing. (Additional note 5)

[0178] The synchronous spiral compressor according to one of the supplementary notes 1 to 3, wherein The outlet section and the outlet communication section are in (fluid) communication with each other in one direction of the axis of rotation. (Additional note 6)

[0179] The synchronous spiral compressor according to claim 5, wherein the outlet section in the housing is formed in an eccentric position with respect to the axis of rotation; and The outlet communication section in the rotating shaft section is formed at a position eccentric with respect to the axis of rotation. (Additional note 7)

[0180] The synchronous spiral compressor according to one of the supplementary notes 1 to 6, wherein, when the flow rate of the fluid to be discharged from / to the compression chamber to / into the outlet chamber is at a minimum, the outlet section and the outlet communication section are in a phase in which the flow resistance is minimized. (Additional note 8)

[0181] The synchronous spiral compressor according to one of the supplementary notes 1 to 7, wherein, when the flow rate of the fluid to be discharged from / to the compression chamber to / into the outlet chamber is at a maximum, the outlet section and the outlet communication section are in a phase in which the flow resistance is maximized. (Additional note 9)

[0182] The synchronous spiral compressor according to one of the supplementary notes 1 to 8, wherein The compression mechanism includes an outlet valve that allows the fluid to be released from the compression chamber into the outlet chamber and prevents the fluid from flowing from the outlet chamber into the compression chamber; and The outlet communication section is positioned downstream of the outlet valve in the direction of flow of the fluid. Commercial applicability

[0183] The present invention is applicable to an air conditioning system for a vehicle or the like. 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 2002-310073

[0002]

Claims

[1] Synchronous spiral compressor with: a housing (6) with an outlet section (63) through which fluid is discharged to an outside; and a compression mechanism (14) which is arranged in the housing (6); wherein the compression mechanism (14) has: a compression chamber (12) in which fluid is compressed while a volume of the compression chamber (12) is reduced; an outlet chamber (91, 92, 93, 94, 95) which communicates with the compression chamber (12) and to which the fluid compressed in the compression chamber (12) is discharged; and a rotating shaft section (37d, 81d, 72d, 85d, 87b) which is supported by the housing (6) via a bearing (52) in such a way as to be rotatable about an axis of rotation (O1); wherein the compression mechanism (14) comprises a drive screw (30) and a driven screw (40), wherein the drive worm (30) is arranged to be rotated by a drive mechanism (10), and has a drive worm end plate (31) and a drive worm spiral body (33) which is formed integrally with the drive worm end plate (31) and projects in a spiral shape in the direction of the driven worm (40), wherein the driven screw (40) faces the drive screw (30) and is arranged to be rotated by the drive screw (30) and a driven mechanism (20) at an eccentric position with respect to the drive screw (30) in order to form the compression chamber (12) between the drive screw (30) and the driven screw (40), wherein the driven worm (40) has a driven worm end plate (41) and a driven worm spiral body (43) which is formed integrally with the driven worm end plate (41) and projects in a spiral shape towards the drive worm (30), characterized by , that the outlet chamber (91, 92, 93, 94, 95) has a diameter that is larger than the outer diameter of the bearing (52); the rotating shaft section (37d, 81d, 72d, 85d, 87b) has an outlet communication section (82, 84) through which the fluid discharged into the outlet chamber (91, 92, 93, 94, 95) flows to the outlet section (63); a phase change between the outlet section (63) and the outlet communication section (82, 84) with rotation of the rotating shaft section (37d, 81d, 72d, 85d, 87b) changes a flow resistance for the fluid flowing from the outlet communication section (82, 84) to the outlet section (63); and The outlet section (63) and the outlet communication section (82, 84) reach a phase in which the flow resistance increases, while the flow rate of the fluid to be discharged from the compression chamber (12) to the outlet chamber (91, 92, 93, 94, 95) approaches a maximum. [2] Synchronous spiral compressor according to claim 1, characterized by , that the compression mechanism (14) has a cover body (37, 81, 83, 85, 87) which is attached to the drive screw (30) or the driven screw (40) and is provided with the rotating shaft section (37d, 81d, 72d, 85d, 87b), and the outlet chamber (91, 92, 93, 94, 95) is formed between the cover body (37, 81, 83, 85, 87) and the drive screw end plate (31) of the drive screw (30) to which the cover body (37, 81, 83, 85, 87) is attached, or between the cover body (37, 81, 83, 85, 87) and the driven screw end plate (41) of the driven screw (40) to which the cover body (37, 81, 83, 85, 87) is attached. [3] Synchronous spiral compressor according to claim 1 or 2, characterized by , that Lubricating oil is discharged into the outlet chamber (91, 92, 93, 94, 95) together with the fluid compressed in the compression chamber (12), and the outlet chamber (91, 92, 93, 94, 95) and a section in the housing (6) where the pressure is lower than that in the outlet chamber (91, 92, 93, 94, 95) are connected via a return channel through which the lubricating oil in the outlet chamber (91, 92, 93, 94, 95) is recirculated. [4] Synchronous spiral compressor according to any one of claims 1 to 3, characterized by , that the outlet section (63) and the outlet communication section (82, 84) are in communication with each other in a radial direction of the housing (6). [5] Synchronous spiral compressor according to any one of claims 1 to 3, characterized by , that the outlet section (63) and the outlet communication section (82, 84) are in communication with each other in one direction of the axis of rotation (O1). [6] Synchronous spiral compressor according to claim 5, characterized by , that the outlet section (63) is formed in the housing (6) at an eccentric position with respect to the axis of rotation (O1); and the outlet communication section (82, 84) in the rotating shaft section (37d, 81d, 72d, 85d, 87b) is formed at an eccentric position with respect to the axis of rotation (O1). [7] Synchronous spiral compressor according to any one of claims 1 to 6, characterized by , that when the flow rate of the fluid to be discharged from the compression chamber (12) to the outlet chamber (91, 92, 93, 94, 95) is at a minimum, the outlet section (63) and the outlet communication section (82, 84) are in a phase in which the flow resistance is minimized. [8] Synchronous spiral compressor according to any one of claims 1 to 7, characterized by , that when the flow rate of the fluid to be discharged from the compression chamber (12) to the outlet chamber (91, 92, 93, 94, 95) is at a maximum, the outlet section (63) and the outlet communication section (82, 84) are in a phase in which the flow resistance is maximized. [9] Synchronous spiral compressor according to any one of claims 1 to 8, characterized by , that the compression mechanism (14) has an outlet valve (57) that allows the fluid to be discharged from the compression chamber (12) into the outlet chamber (91, 92, 93, 94, 95) and prevents the fluid from flowing from the outlet chamber (91, 92, 93, 94, 95) into the compression chamber (12); and the outlet communication section (82, 84) is positioned downstream of the outlet valve (57) in a flow direction in which the fluid flows.

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