JP2016160749A - Variable displacement swash plate compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable displacement swash plate compressor capable of reducing power loss while developing excellent durability and suppressing vibration and resulting noise during operation.SOLUTION: In the compressor according to this invention, each second cylinder bore 23a is formed having a smaller diameter than each first cylinder bore 21a. Between a first flange 430 and the front wall of a first recessed part 21c, a first thrust bearing 35a is held, and between a second flange 431 and the rear wall of a second recessed part 23c, a second thrust bearing 35b is held. A second spring constant K2 of the second thrust bearing 35b is set to be greater than a first spring constant K1 of the first thrust bearing 35a. Thus, with an increase in the discharge capacity to cause thrust force heading to the rear end side of a driving shaft 3 to be greater than thrust force heading to the front end side of the driving shaft 3, the compressor can sufficiently support the greater thrust force.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a variable displacement swash plate compressor.

  Patent Document 1 discloses a conventional variable displacement swash plate compressor (hereinafter simply referred to as a compressor). As shown in FIGS. 4 and 8 of Patent Document 1, this compressor includes a drive shaft, a housing, a swash plate, a link mechanism, a double-headed piston, a conversion mechanism, an actuator, And a control mechanism.

  The housing rotatably supports the drive shaft. A first cylinder bore is formed on the rear side of the housing, in other words, on one end side of the drive shaft. A second cylinder bore is formed on the front side of the housing, in other words, on the other end side of the drive shaft. The second cylinder bore is formed with a smaller diameter than the first cylinder bore. A swash plate chamber is formed between the first cylinder bore and the second cylinder bore in the housing.

  A first thrust bearing is provided between one end of the drive shaft and the housing. A second thrust bearing is provided between the other end of the drive shaft and the housing. The swash plate is provided in the swash plate chamber in a state of being inserted through the drive shaft, and is rotated by the rotation of the drive shaft. The link mechanism is provided between the drive shaft and the swash plate, and allows the inclination angle of the swash plate to be changed. Here, the inclination angle is an angle of the swash plate with respect to a direction orthogonal to the drive axis of the drive shaft.

  The double-headed pistons define a first compression chamber in the first cylinder bore and a second compression chamber in the second cylinder bore. Corresponding to the second cylinder bore having a smaller diameter than the first cylinder bore, the head of the piston on the second cylinder bore side is formed to have a smaller diameter than the head of the piston on the first cylinder bore side. The conversion mechanism reciprocates the piston in the first and second cylinder bores with a stroke corresponding to the inclination angle by the rotation of the swash plate. The actuator can change the tilt angle. The control mechanism controls the actuator.

  In this compressor, when the piston reciprocates in the first and second cylinder bores, the refrigerant is sucked into the first and second compression chambers, and the refrigerant is compressed and discharged. At this time, in this compressor, the first thrust bearing supports the thrust force toward the one end side acting on the drive shaft by the compression reaction force in the second compression chamber, and acts on the drive shaft by the compression reaction force in the first compression chamber. The second thrust bearing supports the thrust force toward the other end. Further, in this compressor, the discharge capacity of the refrigerant can be changed by the actuator changing the inclination angle of the swash plate.

Japanese Patent Laid-Open No. 4-94470

  However, in the conventional compressor, there is no difference between the first thrust bearing and the second thrust bearing. On the other hand, in this compressor, each second cylinder bore has a smaller diameter than each first cylinder bore, and the head on the second cylinder bore side of the piston has a smaller diameter than the head on the first cylinder bore side of the piston. Therefore, the pressure receiving area of the head portion on the first cylinder bore side of the piston is larger than that of the head portion on the second cylinder bore side of the piston. For this reason, in this compressor, as the discharge capacity increases, the thrust force toward the other end side of the drive shaft becomes larger than the thrust force toward the one end side of the drive shaft. If the second thrust bearing is excessively deformed in the direction of the drive shaft, there is a concern that the durability is lowered. In addition, the drive shaft may be excessively displaced toward the other end, and a gap may be generated between the drive shaft and the first thrust bearing or between the first thrust bearing and the housing. As a result, in this compressor, rattling occurs in the drive shaft, and vibration during operation and noise resulting from this increase.

  Therefore, it is conceivable to set both the spring constants of the first and second thrust bearings large so that a large thrust force can be supported. In this case, although the above-described decrease in durability and rattling of the drive shaft can be suppressed, the drag resistance acting on the drive shaft from the first and second thrust bearings increases when the discharge capacity is reduced. . As a result, in this compressor, power loss becomes large.

  The present invention has been made in view of the above-described conventional situation, and exhibits excellent durability, and can reduce power loss while suppressing vibration during operation and noise resulting therefrom. Providing a variable swash plate compressor is a problem to be solved.

The variable displacement swash plate compressor according to the present invention rotatably supports a drive shaft and the drive shaft, a first cylinder bore is formed on one end side of the drive shaft, and a second cylinder is formed on the other end side of the drive shaft. A housing in which a cylinder bore is formed and a swash plate chamber is formed between the first cylinder bore and the second cylinder bore; a swash plate rotatable in the swash plate chamber by rotation of the drive shaft; the drive shaft; A link mechanism provided between the swash plate and allowing a change in the inclination angle of the swash plate with respect to a direction orthogonal to the drive axis of the drive shaft; and a first compression chamber defined in the first cylinder bore; A double-headed piston partitioning the second compression chamber in the second cylinder bore and the swash plate rotate to move the piston in the first cylinder bore and the second cylinder bore with a stroke corresponding to the inclination angle. Comprising a conversion mechanism for moving an actuator capable of changing the inclination angle, and a control mechanism for controlling said actuator,
The second cylinder bore has a smaller diameter than the first cylinder bore;
Between the one end side of the drive shaft and the housing, a first thrust bearing that supports a thrust force directed to the one end side acting on the drive shaft is provided,
Between the other end side of the drive shaft and the housing, a second thrust bearing that supports a thrust force directed to the other end side acting on the drive shaft is provided,
The second spring constant of the second thrust bearing is set to be larger than the first spring constant of the first thrust bearing.

  In the compressor of the present invention, the second spring constant of the second thrust bearing is set larger than the first spring constant of the first thrust bearing. Thereby, in this compressor, even if the discharge capacity increases and the thrust force toward the other end side of the drive shaft becomes larger than the thrust force toward the one end side of the drive shaft, the second thrust bearing moves in the direction of the drive axis. Therefore, the large thrust force can be sufficiently supported. For this reason, this compressor can exhibit high durability. Moreover, in this compressor, since it can suppress that a drive shaft displaces excessively to the other end side, it is hard to produce a clearance gap between a drive shaft and a 1st thrust bearing, or between a 1st thrust bearing and a housing, As a result, rattling is unlikely to occur on the drive shaft.

  In this compressor, it is not necessary to set the first spring constant of the first thrust bearing so large. For this reason, in this compressor, when the discharge capacity is reduced, the drag resistance acting on the drive shaft from the first and second thrust bearings is not excessively increased.

  Therefore, according to the compressor of the present invention, it is possible to reduce power loss while exhibiting excellent durability and suppressing vibration during operation and noise resulting therefrom.

  The second spring constant is preferably set such that the second thrust bearing can be deformed in the direction of the drive shaft. In this case, both the first and second thrust bearings can be deformed in the direction of the drive shaft. As a result, even if the drive shaft is displaced in the direction of the drive shaft, the first and second thrust bearings can preferably follow the displacement, and the first and second thrust bearings preferably support the drive shaft. be able to. Further, by setting a tightening margin for the first and second thrust bearings when the compressor is assembled, it is possible to avoid variations in the first and second spring constants due to the assembly.

  The housing includes a first cylinder block disposed on one end side of the drive shaft and having a first cylinder bore, and a second cylinder block disposed on the other end side of the drive shaft and having a second cylinder bore formed. It is preferable. It is preferable that a first annular portion having an annular shape around the drive shaft center is formed on one end side of the drive shaft. It is preferable that a second annular portion having an annular shape around the drive axis is formed on the other end side of the drive shaft. The first thrust bearing is preferably disposed between the first cylinder block and the first annular portion. The range in which the first annular portion supports the first thrust bearing and the range in which the first cylinder block supports the first thrust bearing are preferably shifted in the radial direction. The second thrust bearing is preferably disposed between the second cylinder block and the second annular portion. The range in which the second annular portion supports the second thrust bearing and the range in which the second cylinder block supports the second thrust bearing are preferably shifted in the radial direction.

  In this case, the first and second thrust bearings are easily elastically deformed in a disc spring shape in the direction of the drive shaft. Moreover, the setting which makes a 2nd spring constant larger than a 1st spring constant is easily realizable.

  The housing includes a first cylinder block disposed on one end side of the drive shaft and having a first cylinder bore, and a second cylinder block disposed on the other end side of the drive shaft and having a second cylinder bore formed. It is preferable. It is preferable that a first annular portion having an annular shape around the drive shaft center is formed on one end side of the drive shaft. It is preferable that a second annular portion having an annular shape around the drive axis is formed on the other end side of the drive shaft. The first thrust bearing is preferably disposed between the first cylinder block and the first annular portion. The second thrust bearing is preferably disposed between the second cylinder block and the second annular portion. The first thrust bearing is sandwiched between one end side first race provided on the first cylinder block side, one end side second race provided on the first annular portion side, one end side first race, and one end side second race. It is preferable to have a plurality of first rolling elements. The second thrust bearing includes a first race on the other end side provided on the second cylinder block side, a second race on the other end side provided on the second annular portion side, a first race on the other end side, and a second end on the other end side. It is preferable to have a plurality of second rolling elements sandwiched between the races. And it is preferable that at least one of the other end side first race and the other end side second race is formed thicker than the one end side first race and the one end side second race.

  Also in this case, the setting for making the second spring constant larger than the first spring constant can be easily realized.

  The outer diameter of the second thrust bearing is preferably set smaller than the outer diameter of the first thrust bearing. Also in this case, the setting for making the second spring constant larger than the first spring constant can be easily realized.

  The actuator is provided with a partition provided on the drive shaft, a connecting portion connected to the swash plate, a movable body movable in the direction of the drive axis in the swash plate chamber, and a partition and the movable body. It is preferable to have a control pressure chamber that moves the moving body so that the inclination angle is increased by introducing the refrigerant from the discharge chamber. The actuator is preferably located on the second cylinder bore side with respect to the swash plate in the swash plate chamber. Since the second cylinder bore has a smaller diameter than the first cylinder bore, it is easy to secure a space for arranging the actuator on the second cylinder bore side. Thereby, in this compressor, it becomes possible to exhibit high controllability by enlarging the actuator while suppressing the enlargement of the compressor itself.

  According to the compressor of the present invention, power loss can be reduced while suppressing vibration during operation and noise resulting therefrom.

FIG. 1 is a cross-sectional view of the compressor of the first embodiment when the capacity is minimum. FIG. 2 is a cross-sectional view of the compressor of the first embodiment at the maximum capacity. FIG. 3 is a schematic diagram illustrating a control mechanism according to the compressor of the first embodiment. FIG. 4 is an enlarged cross-sectional view of a main part illustrating the first cylinder bore, the first thrust bearing, and the like, according to the compressor of the first embodiment. FIG. 5 is an enlarged cross-sectional view of a main part illustrating a second cylinder bore, a second thrust bearing, and the like, according to the compressor of the first embodiment. FIG. 6 is a schematic diagram illustrating a driving shaft supported by first and second thrust bearings in a compressor of a comparative example. (A) shows the support state of the drive shaft by the first and second thrust bearings when the thrust force acting on the drive shaft is small. (B) shows the drive shaft supported by the first and second thrust bearings when the thrust force acting toward the other end of the drive shaft is large with respect to the drive shaft. FIG. 7 is a schematic diagram illustrating the driving shaft supported by the first and second thrust bearings in the compressor of the first embodiment. (A) shows the support state of the drive shaft by the first and second thrust bearings when the thrust force acting on the drive shaft is small. (B) shows the drive shaft supported by the first and second thrust bearings when the thrust force acting toward the other end of the drive shaft is large with respect to the drive shaft. FIG. 8 is an enlarged cross-sectional view of a main part showing a second cylinder bore, a second thrust bearing, and the like, according to the compressor of the second embodiment. FIG. 9 is an enlarged cross-sectional view of a main part illustrating a second cylinder bore, a second thrust bearing, and the like, according to the compressor of the third embodiment. FIG. 10 is an enlarged cross-sectional view of a main part illustrating a second cylinder bore, a second thrust bearing, and the like according to the compressor of the fourth embodiment.

  Embodiments 1 to 4 embodying the present invention will be described below with reference to the drawings. All of these compressors are mounted on a vehicle, and constitute a refrigeration circuit of a vehicle air conditioner.

Example 1
As shown in FIGS. 1 and 2, the double-headed piston swash plate compressor of the first embodiment includes a housing 1, a drive shaft 3, a swash plate 5, a link mechanism 7, a plurality of double-headed pistons 9, and a plurality of pistons. A pair of shoes 11a and 11b and an actuator 13 are provided. Moreover, this compressor is provided with the control mechanism 15 as shown in FIG.

  As shown in FIGS. 1 and 2, the housing 1 includes a first housing 17, a second housing 19, a first cylinder block 21, a second cylinder block 23, a first valve forming plate 39, and a second housing. And an annuloplasty plate 41. In the present embodiment, the front-rear direction of the compressor is defined with the side where the first housing 17 is located as the front side of the compressor and the side where the second housing 19 is located as the rear side of the compressor. The front side of the compressor corresponds to “one end side of the drive shaft” in the present invention, and the rear side of the compressor corresponds to “the other end side of the drive shaft” in the present invention.

  The first housing 17 is formed with a boss 17a protruding forward. A shaft seal device 25 is provided in the boss 17a. A first suction chamber 27a and a first discharge chamber 29a are formed in the first housing 17. The first suction chamber 27 a is formed in an annular shape and is located on the inner peripheral side of the first housing 17. The first discharge chamber 29 a is also formed in an annular shape, and is positioned on the outer peripheral side of the first suction chamber 27 a in the first housing 17.

  Further, the first housing 17 is formed with a first front communication path 18a. The first front communication path 18 a has a front end communicating with the first discharge chamber 29 a and a rear end opening on the rear end surface of the first housing 17.

  The second housing 19 is provided with part of the control mechanism 15 described above. The second housing 19 includes a second suction chamber 27b, a second discharge chamber 29b, and a pressure adjustment chamber 31. The pressure adjustment chamber 31 is located in the central portion of the second housing 19. The second suction chamber 27 b is formed in an annular shape, and is located on the outer peripheral side of the pressure adjustment chamber 31 in the second housing 19. The second discharge chamber 29 b is also formed in an annular shape, and is positioned on the outer peripheral side of the second suction chamber 27 b in the second housing 19.

  Further, a first rear side communication passage 20 a is formed in the second housing 19. The first rear communication path 20 a has a rear end side communicating with the second discharge chamber 29 b and a front end side opening on the front end surface of the second housing 19.

  The first cylinder block 21 is provided on the front side of the compressor and between the first housing 17 and the second cylinder block 23. The first cylinder block 21 is formed with a plurality of first cylinder bores 21a extending in the direction of the drive axis O, and is disposed at equiangular intervals in the circumferential direction. As shown in FIG. 4, each of the first cylinder bores 21 has a bore diameter set to a length L1.

  The first cylinder block 21 is formed with a first shaft hole 21b through which the drive shaft 3 is inserted. A first sliding bearing 22a is provided in the first shaft hole 21b. Further, the first cylinder block 21 is formed with a first recess 21c communicating with the first shaft hole 21b from the rear side of the compressor. The first recess 21c is coaxial with the first shaft hole 21b. Further, the inner diameter of the first recess 21c is set to the length L2, and the inner diameter is made larger than that of the first shaft hole 21b. A first concave surface 21d that is recessed toward the front side of the compressor is formed in an annular shape on the front wall of the first concave portion 21c.

  A first thrust bearing 35a is provided in the first recess 21c. The outer diameter of the first thrust bearing 35a is D1. The first thrust bearing 35a includes a first race 351, a second race 352, a plurality of first rolling elements 353 sandwiched between the first and second races 351 and 352, and the first and second races 351 and 352. And a holder (not shown) for holding the first rolling element 353 therebetween. The first race 351 corresponds to the first race on the one end side in the present invention, and the second race 352 corresponds to the second race on the one end side in the present invention. In the first thrust bearing 35a, the first race 351 and the second race 352 are both formed to a thickness T1.

  The first cylinder block 21 is provided with a first retainer groove 21e for restricting the maximum opening of each first suction reed valve 391a described later. Further, as shown in FIGS. 1 and 2, the first cylinder block 21 is formed with a first communication path 37 a and a second front side communication path 18 b. Each of the first communication path 37 a and the second front side communication path 18 b has a front end opened on the front end face of the first cylinder block 21 and a rear end opened on the rear end face of the first cylinder block 21. .

  The second cylinder block 23 is provided on the rear side of the compressor and between the first cylinder block 21 and the second housing 19. The second cylinder block 23 is joined to the first cylinder block 21, thereby forming a swash plate chamber 33 with the first cylinder block 21. The swash plate chamber 33 communicates with the first recess 21c. Thereby, the first recess 21 c constitutes a part of the swash plate chamber 33.

  The second cylinder block 23 is formed with a plurality of second cylinder bores 23a extending in the direction of the drive axis O. Like the first cylinder bores 21a, the second cylinder bores 23a are arranged at equiangular intervals in the circumferential direction, and are coaxially and paired with the first cylinder bores 21a in the front-rear direction. As shown in FIG. 5, the bore diameter of each second cylinder bore 23a is set to a length L3. Here, the bore diameter length L3 of each second cylinder bore 23a is shorter than the bore diameter length L1 of each first cylinder bore 21a shown in FIG. That is, each second cylinder bore 23a is formed with a smaller diameter than each first cylinder bore 21a. In addition, if the 1st cylinder bore 21a and the 2nd cylinder bore 23a have made a pair, these numbers can be designed suitably. Moreover, the axial center of the 1st cylinder bore 21a and the 2nd cylinder bore 23a which make a pair may be coaxial, and may shift | deviate.

  As shown in FIG. 5, the second cylinder block 23 is formed with a second shaft hole 23 b through which the drive shaft 3 is inserted. A second sliding bearing 22b is provided in the second shaft hole 23b. Instead of the first sliding bearing 22a and the second sliding bearing 22b, rolling bearings may be provided.

  The second cylinder block 23 is formed with a second recess 23c communicating with the second shaft hole 23b from the front side of the compressor. The second recess 23c is coaxial with the 21st shaft hole 23b. The second recess 23c has an inner diameter set to a length L4, and has an inner diameter larger than that of the second shaft hole 23b. Here, the inner length L4 of the second recess 23c is longer than the inner length L2 of the first recess 21c shown in FIG. That is, the second recess 23c is formed with a larger diameter than the first recess 21a. As shown in FIG. 5, a second concave surface 23d that is recessed toward the rear side of the compressor is formed in an annular shape on the rear wall of the second concave portion 23c.

  A second thrust bearing 35b is provided in the second recess 23c. The outer diameter of the second thrust bearing 35a is the length D1 as in the first thrust bearing 35a. The second thrust bearing 35b includes a first race 354, a second race 355, a plurality of second rolling elements 356 sandwiched between the first and second races 354 and 355, and the first and second races 354 and 355. And a holder (not shown) for holding the second rolling element 356 therebetween. The first race 354 corresponds to the first race on the other end side in the present invention, and the second race 355 corresponds to the second race on the other end side in the present invention. Also in the second thrust bearing 35b, the first race 354 and the second race 355 are both formed to a thickness T1. That is, the first thrust bearing 35a shown in FIG. 4 and the second thrust bearing 35b shown in FIG. 5 have the same shape. In addition, about the 1st, 2nd thrust bearings 35a and 35b, it may replace with said each structure and may employ | adopt a slide bearing.

  The second cylinder block 23 is provided with a second retainer groove 23e that restricts the maximum opening degree of each second suction reed valve 411a described later. Further, as shown in FIGS. 1 and 2, the second cylinder block 23 includes a discharge port 230, a merged discharge chamber 231, a third front side communication path 18c, a second rear side communication path 20b, and a suction port. A port 330 and a second communication path 37b are formed. The discharge port 230 and the merged discharge chamber 231 communicate with each other. The merging / discharging chamber 231 is connected via a discharge port 230 to a condenser (not shown) that forms a pipe line. The swash plate chamber 33 is connected via an intake port 330 to an evaporator (not shown) constituting a pipe line.

  The third front side communication path 18 c communicates with the second front side communication path 18 b and the merged discharge chamber 231. The second rear communication path 20 b has a front end communicating with the merging / discharging chamber 231 and a rear end opening on the rear end surface of the second cylinder block 23. The front end side of the second communication path 37 b opens to the swash plate chamber 33, and the rear end side opens to the rear end face of the second cylinder block 23.

  As shown in FIG. 4, the first valve forming plate 39 is provided between the first housing 17 and the first cylinder block 21. The first housing 17 and the first cylinder block 21 are joined via the first valve forming plate 39.

  The first valve forming plate 39 includes a first valve plate 390, a first suction valve plate 391, a first discharge valve plate 392, and a first retainer plate 393. The first valve plate 390 and the first intake valve plate 391 extend to the outer circumferences of the first housing 17 and the first cylinder block 21. The first valve plate 390, the first discharge valve plate 392, and the first retainer plate 393 are formed with the same number of first suction holes 390a as the first cylinder bores 21a. The first valve plate 390 and the first intake valve plate 391 are formed with the same number of first discharge holes 390b as the first cylinder bores 21a. Furthermore, a first suction communication hole 390c is formed in the first valve plate 390, the first suction valve plate 391, the first discharge valve plate 392, and the first retainer plate 393. A first discharge communication hole 390d is formed in the first valve plate 390 and the first suction valve plate 391.

  Each first cylinder bore 21a communicates with the first suction chamber 27a through each first suction hole 390a. Each first cylinder bore 21a communicates with the first discharge chamber 29a through each first discharge hole 390b. The first suction chamber 27a and the first communication path 37a communicate with each other through the first suction communication hole 390c. The first front communication path 18a and the second front communication path 18b communicate with each other through the first discharge communication hole 390d.

  The first suction valve plate 391 is provided on the rear surface of the first valve plate 390. The first suction valve plate 391 is formed with a plurality of first suction reed valves 391a that can open and close each first suction hole 390a by elastic deformation. The first discharge valve plate 392 is provided on the front surface of the first valve plate 390. The first discharge valve plate 392 is formed with a plurality of first discharge reed valves 392a that can open and close each first discharge hole 390b by elastic deformation. The first retainer plate 393 is provided on the front surface of the first discharge valve plate 392. The first retainer plate 393 regulates the maximum opening degree of each first discharge reed valve 392a.

  As shown in FIG. 5, the second valve forming plate 41 is provided between the second housing 19 and the second cylinder block 23. The second housing 19 and the second cylinder block 23 are joined via the second valve forming plate 41.

  The second valve forming plate 41 includes a second valve plate 410, a second suction valve plate 411, a second discharge valve plate 412, and a second retainer plate 413. The second valve plate 410 and the second intake valve plate 411 extend to the outer circumferences of the second housing 19 and the second cylinder block 23. The second valve plate 410, the second discharge valve plate 412 and the second retainer plate 413 are formed with the same number of second suction holes 410a as the second cylinder bores 23a. The second valve plate 410 and the second intake valve plate 411 are formed with the same number of second discharge holes 410b as the second cylinder bores 23a. Further, a second suction communication hole 410c is formed in the second valve plate 410, the second suction valve plate 411, the second discharge valve plate 412 and the second retainer plate 413. A second discharge communication hole 410d is formed in the second valve plate 410 and the second suction valve plate 411.

  Each second cylinder bore 23a communicates with the second suction chamber 27b through each second suction hole 410a. Each second cylinder bore 23a communicates with the second discharge chamber 29b through each second discharge hole 410b. The second suction chamber 27b and the second communication path 37b communicate with each other through the second suction communication hole 410c. The first rear communication path 20a and the second rear communication path 20b communicate with each other through the second discharge communication hole 410d.

  The second intake valve plate 411 is provided on the front surface of the second valve plate 410. The second suction valve plate 411 is formed with a plurality of second suction reed valves 411a that can open and close each second suction hole 410a by elastic deformation. The second discharge valve plate 412 is provided on the rear surface of the second valve plate 410. The second discharge valve plate 412 is formed with a plurality of second discharge reed valves 412a capable of opening and closing each second discharge hole 410b by elastic deformation. The second retainer plate 413 is provided on the rear surface of the second discharge valve plate 412. The second retainer plate 413 regulates the maximum opening degree of each second discharge reed valve 412a.

  As shown in FIGS. 1 and 2, a first discharge communication path 18 is formed by the first front communication path 18a, the first discharge communication hole 390d, the second front communication path 18b, and the third front communication path 18c. Has been. Further, the second discharge communication passage 20 is formed by the first rear communication passage 20a, the second discharge communication hole 410d, and the second rear communication passage 20b.

  The first and second suction chambers 27a and 27b and the swash plate chamber 33 communicate with each other through the first and second communication paths 37a and 37b and the first and second suction communication holes 390c and 410c. Therefore, the pressures in the first and second suction chambers 27a and 27b and the swash plate chamber 33 are substantially equal. Since the low-pressure refrigerant gas that has passed through the evaporator flows into the swash plate chamber 33 through the suction port 330, the first and second discharge chambers 29a are provided in the swash plate chamber 33 and the first and second suction chambers 27a and 27b. , 29b.

  The drive shaft 3 includes a drive shaft main body 30, a first support member 43a, and a second support member 43b. The first support member 43a corresponds to the first annular portion in the present invention. The second support member 43b corresponds to the second annular portion in the present invention.

  The drive shaft main body 30 extends from the front side of the housing 1 toward the rear side in the axial direction. A first small diameter portion 30 a is formed on the front end side of the drive shaft main body 30. A second small diameter portion 30 b is formed on the rear end side of the drive shaft main body 30. The drive shaft body 30 is inserted into the shaft seal device 25 and the first and second sliding bearings 22a and 22b in the housing 1. As a result, the drive shaft main body 30 and thus the drive shaft 3 are pivotally supported by the housing 1 so as to be rotatable around the drive shaft center O. The front end of the drive shaft body 30 is inserted through the shaft seal device 25 in the boss 17a. The rear end of the drive shaft main body 30 protrudes into the pressure adjustment chamber 31.

  The drive shaft main body 30 is provided with the swash plate 5, the link mechanism 7, and the actuator 13. The swash plate 5, the link mechanism 7, and the actuator 13 are respectively disposed in the swash plate chamber 33.

  A threaded portion 3 a is formed at the front end of the drive shaft main body 30. The drive shaft 3 is connected to a pulley or an electromagnetic clutch (not shown) via the screw portion 3a.

  As shown in FIG. 4, the first support member 43 a is formed in a cylindrical shape with the drive axis O as the central axis. The first support member 43a is press-fitted into the first small diameter portion 30a of the drive shaft main body 30, and is supported by the first sliding bearing 22a in the first shaft hole 21d. A first flange 430 is formed on the rear end side of the first support member 43a, and an attachment portion (not shown) through which a second pin 47b described later is inserted is formed.

  The first thrust bearing 35a is sandwiched from the axial direction by the first flange 430 and the front wall of the first recess 21c. Here, the outer diameter of the first flange 430 is set to be larger than the inner diameter of the first thrust bearing 35a and smaller than the outer diameter of the first thrust bearing 35a. As a result, the first thrust bearing 35 a contacts the first flange 430 only on the inner peripheral side of the second race 352. On the other hand, the inner diameter of the first concave surface 21d formed on the front wall of the first recess 21c is set larger than the inner diameter of the first thrust bearing 35a and smaller than the outer diameter of the first thrust bearing 35a. Thus, the first thrust bearing 35a contacts the front wall of the first recess 21d only on the outer peripheral side of the first race 351.

  More specifically, the first thrust bearing 35a is in contact with the first flange 430 in an annular region E1 on the inner peripheral side of the second race 352, and in an annular region on the outer peripheral side of the first race 351. At E2, it contacts the front surface of the first recess 21c. That is, the range in which the first support portion 43a supports the first thrust bearing 35a through the first flange 430 and the range in which the first cylinder block 21 supports the first thrust bearing 35a through the front surface of the first recess 21c are mutually different. Deviation in radial direction. Thus, the first thrust bearing 35a supports a thrust force directed toward the front side that acts on the drive shaft 3 when the compressor is operated, in a state where the first thrust bearing 35a is preloaded to a predetermined value.

  As shown in FIGS. 1 and 2, the front end of the return spring 44a is inserted through the first support member 43a. The return spring 44a extends from the first flange 430 side toward the swash plate 5 side in the direction of the drive axis O.

  As shown in FIG. 5, the second support member 43 b is formed in a cylindrical shape having the drive shaft center O as a central axis. The second support member 43b is press-fitted to the rear end side of the second small diameter portion 30b of the drive shaft main body 30, and is supported by the second sliding bearing 22b in the second shaft hole 23b. A second flange 431 is formed at the front end of the second support member 43b. The second flange 431 has a larger diameter than the first flange 430 shown in FIG.

  As shown in FIG. 5, O-rings 51 b and 51 c are provided in the second support member 43 b at positions closer to the rear end side than the second flange 431. These O-rings 51b and 51c seal between the pressure adjustment chamber 31 and the second recess 23c, and thus between the pressure adjustment chamber 31 and the swash plate chamber 33.

  The second thrust bearing 35b is sandwiched from the axial direction by the second flange 431 and the rear wall of the second recess 23c. Here, the outer diameter of the second flange 431 is set larger than the inner diameter of the second thrust bearing 35b and smaller than the outer diameter of the second thrust bearing 35b. Accordingly, the second thrust bearing 35b contacts the second flange 431 only on the inner peripheral side of the second race 355. On the other hand, the inner diameter of the second concave surface 23d formed on the rear wall of the second recess 23c is set larger than the inner diameter of the second thrust bearing 35b and smaller than the outer diameter of the second thrust bearing 35b. Accordingly, the second thrust bearing 35b contacts the rear wall of the second recess 23c only on the outer peripheral side of the first race 354.

  More specifically, the second thrust bearing 35b is in contact with the second flange 431 in an annular region E3 on the inner peripheral side of the second race 355, and in an annular region on the outer peripheral side of the first race 354. At E4, it contacts the rear surface of the second recess 23c. That is, the range in which the second support portion 43b supports the second thrust bearing 35b through the second flange 431, and the range in which the second cylinder block 23 supports the second thrust bearing 35b through the rear surface of the second recess 23c, They are offset from each other in the radial direction. Thus, the second thrust bearing 35b supports a thrust force directed toward the rear side acting on the drive shaft 3 when the compressor is operated in a state where the second thrust bearing 35b is preloaded to a predetermined value.

  As described above, in a state where the range in which the first support portion 43a supports the first thrust bearing 35a and the range in which the first cylinder block 21 supports the first thrust bearing 35a are shifted in the radial direction, the first thrust Since the bearing 35a is sandwiched between the first flange 430 and the front surface of the first recess 21c, the first thrust bearing 35a can be elastically deformed like a disc spring in the direction of the drive shaft. Similarly, in a state where the range in which the second support portion 43b supports the second thrust bearing 35b and the range in which the second cylinder block 23 supports the second thrust bearing 35b are shifted in the radial direction, the second thrust bearing 35b. Is sandwiched between the second flange 431 and the rear surface of the second recess 23c, the second thrust bearing 35b can also be elastically deformed like a disc spring in the direction of the drive shaft.

  In other words, in this compressor, the first spring constant K1 in the first thrust bearing 35a is set so that the first thrust bearing 35a can be deformed in the direction of the drive axis O. Further, the second spring constant K2 in the second thrust bearing 35b is also set so that the second thrust bearing 35b can be deformed in the direction of the drive axis O. Here, as described above, the second flange 431 is formed to have a larger diameter than the first flange 430. Therefore, the region E3 where the second race 355 and the second flange 431 of the second thrust bearing 35b abut is the region where the second race 352 and the first flange 430 of the first thrust bearing 35a shown in FIG. 4 abut. Greater than E1. That is, the range in which the second thrust bearing 35b shown in FIG. 5 is in contact with the second flange 431 is larger than the range in which the first thrust bearing 35a shown in FIG. 4 is in contact with the first flange 430. For this reason, the second thrust bearing 35b is less likely to be deformed in the direction of the drive axis O than the first thrust bearing 35a. That is, in this compressor, the second spring constant K2 of the second thrust bearing 35b is set larger than the first spring constant K1 of the first thrust bearing 35a.

  In Example 1, the region E4 where the first race 354 of the second thrust bearing 35b shown in FIG. 5 contacts the rear surface of the second recess 23c is the first race 351 of the first thrust bearing 35a shown in FIG. Is set to the same size as the region E2 where the first recess 21c comes into contact with the front surface of the first recess 21c, but the second spring of the second thrust bearing 35b can also be obtained by making the inner diameter of the region E4 smaller than the inner diameter of the region E2. The constant K2 can be set larger than the first spring constant K1 of the first thrust bearing 35a.

  As shown in FIGS. 1 and 2, the swash plate 5 has an annular flat plate shape and has a front surface 5a and a rear surface 5b. The front surface 5 a faces the front side of the compressor in the swash plate chamber 33. The rear surface 5 b faces the rear side of the compressor in the swash plate chamber 33.

  The swash plate 5 has a ring plate 45. The ring plate 45 is formed in an annular flat plate shape, and an insertion hole 45a is formed at the center. The swash plate 5 is attached to the drive shaft 3 by inserting the drive shaft main body 30 through the insertion hole 45 a in the swash plate chamber 33. The ring plate 45 is formed with a connecting portion (not shown) that is connected to each connecting arm 132 described later.

  The link mechanism 7 has a lug arm 49. The lug arm 49 is disposed in front of the swash plate 5 in the swash plate chamber 33 and is positioned between the swash plate 5 and the first support member 43a. The lug arm 49 is formed to be substantially L-shaped from the front end side toward the rear end side. On the rear end side of the lug arm 49, a weight portion 49a is formed. The weight portion 49 a extends in the circumferential direction of the actuator 13 and covers approximately half the circumference of the actuator 13. The shape of the weight portion 49a can be designed as appropriate.

  The rear end side of the lug arm 49 is connected to the ring plate 45 by the first pin 47a. Thereby, the lug arm 49 is supported by the ring plate 45, that is, the swash plate 5 so as to be swingable around the first swing axis M1 with the first pin 47a as the first swing axis M1. ing. The first swing axis M1 extends in a direction orthogonal to the drive axis O of the drive shaft 3.

  The front end side of the lug arm 49 is connected to the first support member 43a by the second pin 47b. As a result, the lug arm 49 can swing around the second swing axis M2 with respect to the first support member 43a, that is, the drive shaft 3, with the second pivot 47b serving as the second pivot axis M2. It is supported. The second swing axis M2 extends in parallel with the first swing axis M1. The link mechanism 7 in the present invention is constituted by the lug arm 49 and the first and second pins 47a and 47b.

  The weight portion 49a is provided to extend to the rear end side of the lug arm 49, that is, on the opposite side of the second swing axis M2 with respect to the first swing axis M1. For this reason, the lug arm 49 is supported by the ring plate 45 by the first pin 47 a, so that the weight portion 49 a passes through the groove portion 45 b of the ring plate 45 and faces the rear surface of the ring plate 45, that is, the rear surface 5 b side of the swash plate 5. To position. Then, the centrifugal force generated when the swash plate 5 rotates around the drive axis O also acts on the weight portion 49a on the rear surface 5b side of the swash plate 5.

  In this compressor, the swash plate 5 and the drive shaft 3 are connected by the link mechanism 7 so that the swash plate 5 can rotate together with the drive shaft 3. Further, the both ends of the lug arm 49 swing around the first swing axis M1 and the second swing axis M2, respectively, so that the swash plate 5 moves from the minimum value shown in FIG. 1 to the maximum value shown in FIG. The inclination angle can be changed.

  As shown in FIGS. 1 and 2, each piston 9 is a double-headed piston, and has a first head 9a on the front end side and a second head 9b on the rear end side. Corresponding to each second cylinder bore 23a having a smaller diameter than each first cylinder bore 21a, each second head 9b is formed with a smaller diameter than each first head 9a.

  Each first head 9a is accommodated in each first cylinder bore 21a so as to be capable of reciprocating. The first compression chambers 53a are defined in the first cylinder bores 21a by the first heads 9a and the first valve forming plate 39, respectively. Each second head portion 9b is accommodated in each second cylinder bore 23a so as to be capable of reciprocating. The second compression chambers 53b are defined in the second cylinder bores 23a by the second heads 9b and the second valve forming plate 41, respectively.

  Here, in this compressor, the top dead center positions of the first heads 9a and the second heads 9b move as the strokes of the pistons 9 change as the inclination angle of the swash plate 5 changes. To do. Specifically, as the inclination angle of the swash plate 5 becomes smaller, the top dead center position of each second head 9b moves larger than the top dead center position of each first head 9a.

  The actuator 13 is disposed in the swash plate chamber 33. More specifically, the actuator 13 has a second cylinder bore 23 a formed in the swash plate chamber 33 at the rear side of the swash plate 5, that is, the actuator 13 in the swash plate chamber 33 with reference to the swash plate 5. It is located on the second cylinder block 23 side. Thereby, the actuator 13 can enter the second recess 23c.

  The actuator 13 has a moving body 13a, a partitioning body 13b, and a control pressure chamber 13c. The control pressure chamber 13c is formed between the movable body 13a and the partition body 13b. The moving body 13a has a rear wall 130, a peripheral wall 131, and a pair of pulling arms 132. Each pulling arm 132 corresponds to a connecting portion in the present invention. 1 and 2, only one of the pair of pulling arms 132 is shown.

  The rear wall 130 is located behind the movable body 13a and extends in the radial direction in a direction away from the drive axis O. The rear wall 130 is provided with an insertion hole 130a through which the second small diameter portion 30b of the drive shaft main body 30 is inserted. An O-ring 51d is provided in the insertion hole 130a. The peripheral wall 131 is continuous with the outer peripheral edge of the rear wall 130 and extends toward the front of the moving body 13a. Each traction arm 132 is formed at the front end of the peripheral wall 131 with the drive axis O interposed therebetween, and projects toward the front of the movable body 13a. Each pulling arm 132 corresponds to a connecting portion in the present invention. By these rear wall 130, peripheral wall 131, and each pulling arm 132, the movable body 13a has a bottomed cylindrical shape.

  The partition body 13b is formed in a disk shape having substantially the same diameter as the inner diameter of the moving body 13a. The partition 13b has an insertion hole 133 extending through the center. An O-ring 51e is provided on the outer periphery of the partition 13b.

  Between the partition 13b and the ring plate 45, a tilt angle reducing spring 44b is provided. Specifically, the rear end of the tilt angle reducing spring 44b is disposed so as to contact the partitioning body 13b, and the front end of the tilt angle decreasing spring 44b is disposed so as to contact the ring plate 45. The inclination-decreasing spring 44b urges both the partition 13b and the ring plate 45 so that they are remote from each other.

  The drive shaft main body 30 is inserted through the insertion hole 130a of the moving body 13a. Thereby, the moving body 13a can move the drive shaft main body 30 in the direction of the drive axis O. On the other hand, the drive shaft main body 30 is press-fitted into the insertion hole 133 of the partition 13b. As a result, the partition body 13 b is fixed to the drive shaft main body 30, and the partition body 13 b can rotate together with the drive shaft main body 30. The partition 13b may also be inserted through the drive shaft main body 30 so as to be movable in the direction of the drive axis O.

  The partition 13b is disposed in the movable body 13a behind the swash plate 5, and the periphery thereof is surrounded by the peripheral wall 131. Thereby, when the moving body 13a moves in the direction of the drive axis O, the inner peripheral surface of the peripheral wall 131 of the moving body 13a and the outer peripheral surface of the partition 13b slide.

  And the control body 13c is formed between the mobile body 13a and the division body 13b because the division body 13b is surrounded by the surrounding wall 131. FIG. The control pressure chamber 13c is partitioned from the swash plate chamber 33 by the rear wall 130, the peripheral wall 131, and the partition body 13b.

  Each pulling arm 132 and the ring plate 45 are connected by a third pin 47c. Accordingly, the swash plate 5 is supported by the movable body 13a so as to be swingable around the action axis M3 with the axis of the third pin 47c as the action axis M3. The action axis M3 extends in parallel with the first and second oscillation axes M1 and M2. Thus, the moving body 13a is connected to the swash plate 5. Then, the movable body 13a is connected to the swash plate 5, so that the partition 13b and the swash plate 5 face each other.

  In the second small diameter portion 30b, an axial path 3b extending in the direction of the drive axis O from the rear end toward the front, and a radial path 3c extending in the radial direction from the front end of the axial path 3b and opening to the outer peripheral surface of the drive shaft main body 30. And are formed. The rear end of the axial path 3 b communicates with the pressure adjustment chamber 31. On the other hand, the path 3c communicates with the control pressure chamber 13c. Thereby, the control pressure chamber 13c communicates with the pressure regulation chamber 31 through the radial path 3c and the axial path 3b.

  As shown in FIG. 3, the control mechanism 15 has an extraction passage 15a, an air supply passage 15b, a control valve 15c, an orifice 15d, an axial path 3b, and a radial path 3c.

  The extraction passage 15a is connected to the pressure adjustment chamber 31 and the second suction chamber 27b. The control pressure chamber 13c, the pressure adjustment chamber 31, and the second suction chamber 27b communicate with each other through the extraction passage 15a, the axial path 3b, and the radial path 3c. The air supply passage 15b is connected to the pressure adjusting chamber 31 and the second discharge chamber 29b. The control pressure chamber 13c, the pressure adjustment chamber 31, and the second discharge chamber 29b are communicated with each other by the air supply passage 15b, the axial path 3b, and the radial path 3c. An orifice 15d is provided in the supply passage 15b.

  The control valve 15c is provided in the extraction passage 15a. The control valve 15c can adjust the opening degree of the extraction passage 15a based on the pressure in the second suction chamber 27b.

  In this compressor, a pipe connected to the evaporator is connected to the suction port 330 shown in FIGS. 1 and 2, and a pipe connected to the condenser is connected to the discharge port 230. The condenser is connected to the evaporator via a pipe and an expansion valve. These compressors, evaporators, expansion valves, condensers and the like constitute a refrigeration circuit for a vehicle air conditioner. In addition, illustration of an evaporator, an expansion valve, a condenser, and each piping is abbreviate | omitted.

  In the compressor configured as described above, when the drive shaft 3 rotates, the swash plate 5 rotates, and each piston 9 reciprocates in the first cylinder bore 21a and the second cylinder bore 23a. For this reason, the first and second compression chambers 53a and 53b change in volume according to the piston stroke. Therefore, in this compressor, the suction stroke for sucking the refrigerant gas into the first and second compression chambers 53a and 53b, the compression stroke for compressing the refrigerant gas in the first and second compression chambers 53a and 53b, and the compression are performed. The discharge stroke and the like in which the refrigerant gas is discharged into the first and second discharge chambers 29a and 29b are repeatedly performed.

  The refrigerant gas discharged into the first discharge chamber 29 a reaches the merged discharge chamber 231 through the first discharge communication path 18. Similarly, the refrigerant gas discharged into the second discharge chamber 29 b reaches the merged discharge chamber 231 through the second discharge communication path 20. Then, the refrigerant gas reaching the merged discharge chamber 231 is discharged from the discharge port 230 to the condenser via the pipe.

  During these suction strokes and the like, a piston compression force that reduces the inclination angle of the swash plate 5 acts on the rotating body including the swash plate 5, the ring plate 45, the lug arm 49, and the first pin 47a. If the inclination angle of the swash plate 5 is changed, it is possible to perform capacity control by increasing or decreasing the stroke of the piston 9.

  Specifically, in the control mechanism 15 shown in FIG. 3, if the control valve 15c increases the opening degree of the extraction passage 15a, the pressure in the pressure adjusting chamber 31 and, in turn, the pressure in the control pressure chamber 13c are changed to the second suction chamber. The pressure in the control pressure chamber 13c and the swash plate chamber 33 are reduced, and the variable differential pressure, which is substantially equal to the pressure in 27b, is reduced. Therefore, due to the piston compression force acting on the swash plate 5, the moving body 13 a moves toward the front side of the swash plate chamber 33 in the actuator 13 as shown in FIG. 1.

  As a result, in this compressor, the swash plate 5 is urged in the direction in which the inclination angle decreases by the compression reaction force acting on the swash plate 5 via each piston 9, and each traction arm 132 is applied at the action axis M <b> 3. Through this, the moving body 13a is pulled to the front side of the swash plate chamber 33, and the ring plate 45 contacts the rear end of the return spring 44a. Then, the movable body 13a is pulled to the front side of the swash plate chamber 33, and in this compressor, the swash plate 5 is swung clockwise around the action axis M3 while resisting the urging force of the return spring 44a. Move. Further, the rear end of the lug arm 49 swings counterclockwise around the first swing axis M1, and the front end of the lug arm 49 swings counterclockwise around the second swing axis M2. For this reason, the front end side of the lug arm 49 approaches the first flange 430 of the first support member 43a. As a result, the swash plate 5 swings with the operating axis M3 as the operating point and the first swinging axis M1 as the fulcrum. For this reason, the inclination angle of the swash plate 5 with respect to the drive axis O of the drive shaft 3 decreases, and the stroke of each piston 9 decreases. For this reason, in this compressor, the discharge capacity per one rotation of the drive shaft 3 becomes small.

  Moreover, in this compressor, the centrifugal force which acted on the weight part 49a is also given to the swash plate 5. For this reason, in this compressor, it is easy to displace the swash plate 5 in the direction to reduce the inclination angle.

  In this compressor, the inclination angle of the swash plate 5 is reduced and the stroke of each piston 9 is reduced, so that the top dead center position of each second head 9 b is remote from the second valve forming plate 41. For this reason, in this compressor, when the inclination angle of the swash plate 5 approaches zero degrees, the compression work is slightly performed on the first compression chamber 53a side, while the compression work is performed on the second compression chamber 53b side. Disappear.

  On the other hand, in the control mechanism 15 shown in FIG. 3, if the control valve 15c reduces the opening degree of the extraction passage 15a, the pressure in the pressure adjustment chamber 31 is increased by the pressure of the refrigerant gas in the second discharge chamber 29b, and the control is performed. The pressure in the pressure chamber 13c increases. For this reason, the variable differential pressure, which is the differential pressure between the control pressure chamber 13c and the swash plate chamber 33, increases. Thereby, in the actuator 13, the moving body 13a moves from the position shown in FIG. 1 toward the rear side against the piston compressive force acting on the swash plate 5, and as shown in FIG. It penetrates into the second recess 23c.

  As a result, in this compressor, the moving body 13a pulls the swash plate 5 to the rear side of the swash plate chamber 33 through the respective traction arms 132 at the action axis M3 while resisting the urging force of the inclination decreasing spring 44b. For this reason, in this compressor, the swash plate 5 swings counterclockwise around the action axis M3. The rear end of the lug arm 49 swings clockwise around the first swing axis M1, and the front end of the lug arm 49 swings clockwise around the second swing axis M2. For this reason, the front end side of the lug arm 49 moves rearward from the first flange 430 of the first support member 43a. As a result, the swash plate 5 swings in the opposite direction to the case where the inclination angle becomes small, with the action axis M3 and the first swing axis M1 as the action point and the fulcrum, respectively. For this reason, the inclination angle of the swash plate 5 with respect to the drive axis O of the drive shaft 3 increases, and the stroke of each piston 9 increases. For this reason, in this compressor, the discharge capacity per one rotation of the drive shaft 3 becomes large.

  In this compressor, the first and second cylinder bores 21a and 23a are formed, and the refrigerant gas is compressed in each of the first and second compression chambers 53a and 53b, for example, to compress the refrigerant only in the first compression chamber 53a. Compared with the case where it does, it becomes possible to enlarge the discharge capacity per rotation of the drive shaft 3. FIG. Even when the discharge capacity is reduced, the refrigerant gas compression process is performed on the side of each first compression chamber 53a, that is, on the side of each first cylinder bore 21a that has a larger diameter than each second cylinder bore 23a. Therefore, it is possible to ensure a necessary discharge capacity.

  Here, in this compressor, each second cylinder bore 23a is formed with a smaller diameter than each first cylinder bore 21a, and each second head 9b is formed with a smaller diameter than each first head 9a. The pressure receiving area of each first head 9a is larger than each second head 9b. For this reason, in this compressor, as the discharge capacity increases, the thrust force toward the rear end side of the drive shaft 3 during operation becomes larger than the thrust force toward the front end side of the drive shaft 3.

  In this respect, in this compressor, the second flange 431 is formed to have a larger diameter than the first flange 430, and the second race 352 and the first flange 430 of the first thrust bearing 35a shown in FIG. The region E3 where the second race 355 and the second flange 431 of the second thrust bearing 35b shown in FIG. 5 are in contact with each other is larger than the region E1 where the contact is made. Thereby, in this compressor, the second spring constant K2 of the second thrust bearing 35b is set larger than the first spring constant K1 of the first thrust bearing 35a. For this reason, in this compressor, even if the discharge capacity increases and the thrust force toward the rear end side of the drive shaft 3 becomes larger than the thrust force toward the front end side of the drive shaft 3, the large thrust force is sufficiently increased. It is possible to support.

  Regarding the above-described operation in this compressor, the schematic diagram of the compressor of the comparative example shown in FIGS. 6A and 6B and the compressor of Example 1 shown in FIGS. 7A and 7B. A specific description will be given while comparing schematic diagrams. In the compressor of the comparative example, unlike the compressor of the first embodiment, the second spring constant K22 of the second thrust bearing 35b is set to the same value as the first spring constant K1 of the first thrust bearing 35a. Except for this point, the configuration of the compressor of the comparative example is the same as that of the compressor of the first embodiment.

  As shown in FIG. 6A, even in the compressor of the comparative example, when the discharge capacity is small and the thrust force toward the front end side acting on the drive shaft 3 and the thrust force toward the rear end side are small, The first and second thrust bearings 35a and 35b can suitably support the drive shaft 3. However, as shown in FIG. 6B, as the discharge capacity increases and the thrust force F toward the rear end acting on the drive shaft 3 increases, the second thrust bearing 35b moves in the direction of the drive axis O. Deformation increases. Thus, if it deform | transforms excessively in the drive shaft center O direction, durability of the 2nd thrust bearing 35b will fall easily.

  Further, the thrust force F acting on the drive shaft 3 toward the rear end side causes the second thrust bearing 35b to be greatly deformed in the direction of the drive shaft center O, so that the drive shaft 3 can be moved from the small discharge capacity to the rear of the compressor. If the distance M1 is moved to the end side, the first thrust bearing 35a may extend to the limit and be separated from the drive shaft 3. That is, the first thrust bearing 35a cannot sufficiently support the drive shaft 3 even by elastic deformation, and a gap may be generated between the drive shaft 3 and the first thrust bearing 35a. As a result, in the compressor of the comparative example, rattling occurs in the drive shaft 3, and vibration during operation and noise resulting therefrom increase.

  On the other hand, in the compressor of the first embodiment, the second spring constant K2 of the second thrust bearing 35b is set larger than the first spring constant K1 of the first thrust bearing 35a. Therefore, FIG. As shown in FIG. 7B, the discharge capacity is increased and the thrust force F toward the rear end acting on the drive shaft 3 is large as shown in FIG. The first and second thrust bearings 35a and 35b can suitably support the drive shaft 3. That is, even if the thrust force F acting on the drive shaft 3 toward the rear end increases, in the compressor of the first embodiment, the deformation of the second thrust bearing 35b in the direction of the drive axis O is small. Thus, in the compressor of Example 1, since the excessive deformation | transformation of the drive shaft center O direction in the 2nd thrust bearing 35b can be suppressed compared with the compressor of a comparative example, durability of the 2nd thrust bearing 35b is made high. can do.

  Further, since the deformation of the second thrust bearing 35b in the direction of the drive axis O is small, the drive shaft 3 is moved from the state where the discharge capacity is small to the rear of the compressor even by the thrust force F acting on the drive shaft 3 toward the rear end side. Only the distance M2 shorter than the distance M1 moves to the end side. Thereby, in the compressor of Example 1, a clearance gap does not arise between the drive shaft 3 and the 1st thrust bearing 35a, but the 1st thrust bearing 35a can fully support the drive shaft 3. As a result, in the compressor according to the first embodiment, it is difficult for the drive shaft 3 to rattle even when the discharge capacity is large.

  Further, in the compressor of the first embodiment, it is not necessary to set the first spring constant K1 of the first thrust bearing 35a so large when supporting a large thrust force. For this reason, in the compressor according to the first embodiment, the drag resistance acting on the drive shaft 3 from the first and second thrust bearings 35a and 35b becomes excessively large when the discharge capacity shown in FIG. There is nothing.

  Therefore, according to the compressor of the first embodiment, excellent durability can be exhibited, and power loss can be reduced while suppressing vibration during operation and noise resulting therefrom.

  In particular, in this compressor, in the first thrust bearing 35a, the range in which the first flange 430 supports the first race 351, that is, the region E1, and the range in which the front surface of the first recess 21c supports the second race 352, that is, The region E2 is displaced in the radial direction. Similarly, in the second thrust bearing 35b, the range in which the second flange 431 supports the first race 354, that is, the region E3, and the range in which the rear surface of the second recess 23c supports the second race 355, that is, the region E4. Deviation in radial direction.

  As a result, in this compressor, both the first and second thrust bearings 35a and 35b can be elastically deformed in the shape of a disc spring in the drive axis direction O, and the drive shaft 3 is driven by the thrust force described above. Even if it is displaced in the direction, the first and second thrust bearings 35a and 35b can suitably follow the displacement. Therefore, in this compressor, the first and second thrust bearings 35a and 35b can suitably support the drive shaft 3, respectively. Further, in this compressor, by setting the tightening allowance for the first and second thrust bearings 35a and 35b at the time of assembly, it is possible to avoid variations in the first and second spring constants K1 and K2 for each individual due to the assembly. it can.

  In this compressor, the second race 355 and the second flange 431 of the second thrust bearing 35b come into contact with each other than the region E1 where the second race 352 and the first flange 430 of the first thrust bearing 35a make contact. Region E3 is larger. As a result, in this compressor, as described above, both the first and second thrust bearings 35a and 35b can be deformed in the drive axis direction O, respectively, and the first spring constant K1 of the first thrust bearing 35a can be easily set. As a result, the second spring constant K2 of the second thrust bearing 35b can be set larger.

  Further, in this compressor, each second cylinder bore 23a is formed with a smaller diameter than each first cylinder bore 21a, so that the second recess 23c is made larger than the first recess 21c without increasing the size of the second cylinder block 23. Can also be enlarged. For this reason, in this compressor, the size of the compressor itself is increased by arranging the actuator 13 on the second cylinder block 23 side where each second cylinder bore 23a is formed in the swash plate chamber 33 with reference to the swash plate 5. The large actuator 13 can be employed without doing so. Thereby, in this compressor, since the pressure receiving area of the moving body 13a can be enlarged and the moving body 13a can be moved by a big thrust, high controllability can be exhibited.

(Example 2)
The compressor of the second embodiment is provided with a second thrust bearing 35c shown in FIG. 8 instead of the second thrust bearing 35b in the compressor of the first embodiment. Moreover, in this compressor, the 2nd flange 431 is formed in the same diameter as the 1st flange 430 (refer FIG. 4).

  As shown in FIG. 8, the outer diameter of the second thrust bearing 35a is a length D1, similar to the first and second thrust bearings 35a and 35b. The second thrust bearing 35c includes a first race 357, a second race 358, a plurality of second rolling elements 359 sandwiched between the first and second races 357 and 358, and the first and second races 357 and 358. And a holder (not shown) for holding the second rolling element 359 therebetween. The first race 357 corresponds to the first race on the other end side in the present invention, and the second race 358 corresponds to the second race on the other end side in the present invention. Here, in the 2nd thrust bearing 35c, both the 1st race 357 and the 2nd race 358 are formed in thickness T2. This thickness T2 is thicker than the thickness T1 of the first and second races 351 and 352 of the first thrust bearing 35a shown in FIG. That is, the first and second races 357 and 358 of the second thrust bearing 35c are formed thicker than the first and second races 351 and 352 of the first thrust bearing 35a. For example, only the first race 357 may be formed with the thickness T2, and the second race 358 may be formed with the thickness T1 as in the compressor of the first embodiment.

  Similar to the compressor of the first embodiment, also in this compressor, the second thrust bearing 35c is sandwiched from the axial direction by the second flange 431 and the rear wall of the second recess 23c. The second thrust bearing 35b abuts on the second flange 431 in an annular region E5 which is the inner peripheral side of the second race 358, and the second thrust bearing 35b is second in the annular region E4 which is the outer peripheral side of the first race 357. It contacts the rear surface of the recess 23c. That is, also in this compressor, the range in which the second support portion 43b supports the second thrust bearing 35c through the second flange 431 and the second cylinder block 23 supports the second thrust bearing 35c through the rear surface of the second recess 23c. Range to be shifted from each other in the radial direction. Here, as described above, the second flange 431 is formed to have the same diameter as the first flange 430. Accordingly, in this compressor, the region E5 where the second race 358 of the second thrust bearing 35b and the second flange 431 come into contact with each other is the second race 352 and the first flange 430 of the first thrust bearing 35a shown in FIG. Is set to a size equal to the region E1 where the two abut. Other configurations of the compressor are the same as those of the compressor according to the first embodiment, and the same components are denoted by the same reference numerals and detailed description thereof is omitted.

  In this compressor, the first and second races 357 and 358 of the second thrust bearing 35c are formed thicker than the first and second races 351 and 352 of the first thrust bearing 35a, so that the second thrust bearing 35c It is less likely to be elastically deformed like a disc spring in the direction of the drive axis O than the one thrust bearing 35a. That is, also in this compressor, the second spring constant K2 of the second thrust bearing 35c is set larger than the first spring constant K1 of the first thrust bearing 35a. Thereby, also in this compressor, it is possible to show | play the effect | action similar to the compressor of Example 1. FIG.

(Example 3)
The compressor of the third embodiment is provided with a second thrust bearing 35d shown in FIG. 9 instead of the second thrust bearing 35b in the compressor of the first embodiment. Further, like the compressor of the second embodiment, also in this compressor, the second flange 431 is formed with the same diameter as the first flange 430 (see FIG. 4).

  As shown in FIG. 9, the second thrust bearing 35d includes a first race 361, a second race 362, a plurality of second rolling elements 363 sandwiched between the first and second races 361, 362, and a first And a cage (not shown) that holds the second rolling element 363 between the two races 361 and 362. The first race 361 corresponds to the first race on the other end side in the present invention, and the second race 362 corresponds to the second race on the other end side in the present invention. In the second thrust bearing 35d, the first race 361 and the second race 362 are both formed at a thickness T1, and the thickness is equal to the first and second races 351 and 352 of the first thrust bearing 35a shown in FIG. It has become. On the other hand, as shown in FIG. 9, the outer diameter D2 of the second thrust bearing 35d is smaller than the outer diameter D1 of the first thrust bearing 35a. That is, the second thrust bearing 35d is formed with a smaller diameter than the first thrust bearing 35a.

  Similar to the compressor of the first embodiment, also in this compressor, the second thrust bearing 35d is sandwiched in the axial direction by the second flange 431 and the rear wall of the second recess 23c. The second thrust bearing 35d is in contact with the second flange 431 in an annular region E5 that is the inner peripheral side of the second race 362, and is second in the annular region E6 that is the outer peripheral side of the first race 361. It contacts the rear surface of the recess 23c. That is, also in this compressor, the range in which the second support portion 43b supports the second thrust bearing 35d through the second flange 431 and the second cylinder block 23 supports the second thrust bearing 35d through the rear surface of the second recess 23c. Range to be shifted from each other in the radial direction. Here, as described above, the outer diameter D2 of the second thrust bearing 35d is smaller than the outer diameter D1 of the first thrust bearing 35a. Accordingly, in this compressor, the region E6 where the second race 358 of the second thrust bearing 35b and the second flange 431 come into contact with each other is the first race 351 and the first recess 21c of the first thrust bearing 35a shown in FIG. Is set to be smaller than the region E2 where the front surface is in contact. Other configurations of this compressor are the same as those of the compressor of the first embodiment.

  In this compressor, the outer diameter D2 of the second thrust bearing 35d is made smaller than the outer diameter D1 of the first thrust bearing 35a, so that the second thrust bearing 35d is in the direction of the drive shaft O than the first thrust bearing 35a. It is hard to be elastically deformed like a flat spring. That is, also in this compressor, the second spring constant K2 of the second thrust bearing 35d is set larger than the first spring constant K1 of the first thrust bearing 35a. Thereby, also in this compressor, it is possible to show | play the effect | action similar to the compressor of Example 1. FIG.

Example 4
As shown in FIG. 10, in the compressor of the fourth embodiment, unlike the compressor of the first embodiment, the second concave surface 23d is not formed on the rear wall of the second concave portion 23c. In this compressor, the second flange 431 is formed to have substantially the same diameter as the outer diameter of the second thrust bearing 35b. Thus, in this compressor, the second thrust bearing 35b is clamped from the axial direction by the second flange 431 and the rear wall of the second recess 23c, so that the second thrust bearing 35b In contact with the second flange 431 in the region. The second thrust bearing 35b contacts the rear surface of the second recess 23c in the entire region of the first race 354. That is, in this compressor, the second thrust bearing 35b is rigidly provided between the second flange 431 and the rear wall of the second recess 23c. Other configurations of this compressor are the same as those of the compressor of the first embodiment.

  In this compressor, the second thrust bearing 35b is rigidly provided, so that the second thrust bearing 35b is less likely to be elastically deformed in the direction of the drive shaft O compared to the first thrust bearing 35a. For this reason, in this compressor, the second spring constant K2 of the second thrust bearing 35b is larger than the first spring constant K1 of the first thrust bearing 35a. Note that the first spring constant K1 of the first thrust bearing 35a needs to be smaller than the second spring constant K2 of the second thrust bearing 35b. Thus, this compressor can achieve the same operation as the compressor of the first embodiment.

  In the above, the present invention has been described with reference to the first to fourth embodiments. However, the present invention is not limited to the first to fourth embodiments, and can be appropriately modified and applied without departing from the spirit of the present invention. Needless to say.

  For example, you may comprise a compressor by combining suitably the structure of each compressor of Examples 1-4.

  Further, by forming the first thrust bearing 35a and the second thrust bearings 35b to 35d from different materials, the second spring constant K2 of the second thrust bearings 35b to 35d is set to the first spring of the first thrust bearing 35a. You may set larger than the constant K1.

  The control mechanism 15 may be configured such that a control valve 15c is provided for the air supply passage 15b and an orifice 15d is provided in the extraction passage 15a. In this case, the opening degree of the supply passage 15b can be adjusted by the control valve 15c. As a result, the control pressure chamber 13b can be quickly increased in pressure by the pressure of the refrigerant gas in the second discharge chamber 29b, and the discharge capacity can be increased rapidly.

  The present invention can be used for an air conditioner or the like.

DESCRIPTION OF SYMBOLS 1 ... Housing 3 ... Drive shaft 5 ... Swash plate 7 ... Link mechanism 9 ... Piston 9a ... 1st head 9b ... 2nd head 11a, 11b ... Shoe (conversion mechanism)
DESCRIPTION OF SYMBOLS 13 ... Actuator 13a ... Moving body 13b ... Partition body 13c ... Control pressure chamber 15 ... Control mechanism 21 ... 1st cylinder block 21a ... 1st cylinder bore 23 ... 2nd cylinder block 23a ... 2nd cylinder bore 27a ... 1st suction chamber 27b ... 2nd suction chamber 29a ... 1st discharge chamber 29b ... 2nd discharge chamber 35a ... 1st thrust bearing 35b-35d ... 2nd thrust bearing K1 ... 1st spring constant K2 ... 2nd spring constant 43a ... 1st support member (1st 1 annular part)
43b ... 2nd support member (2nd annular part)
132 ... Traction arm (connection part)
351 ... 1st race (1st race on one end side)
352 ... 2nd race (1st side 2nd race)
354 ... 1st race (the other race side 1st race)
355 ... Second race (second race on the other end side)
357 ... 1st race (1st race on the other end side)
358 ... 2nd race (second race on the other end side)
361 ... 1st race (1st race on the other end side)
362 ... second race (second race on the other end side)
O ... Drive shaft center

Claims (5)

A drive shaft and the drive shaft are rotatably supported, a first cylinder bore is formed on one end side of the drive shaft, a second cylinder bore is formed on the other end side of the drive shaft, and the first cylinder bore and the first cylinder bore A housing in which a swash plate chamber is formed between two cylinder bores, a swash plate rotatable in the swash plate chamber by rotation of the drive shaft, and provided between the drive shaft and the swash plate, the drive shaft A link mechanism that allows a change in the inclination angle of the swash plate with respect to a direction orthogonal to the drive axis of the first and second heads that define the first compression chamber in the first cylinder bore and the second compression chamber in the second cylinder bore A piston, a conversion mechanism for reciprocating the piston in the first cylinder bore and the second cylinder bore with a stroke corresponding to the tilt angle by rotation of the swash plate, and the tilt angle Comprising an actuator capable of changing, and a control mechanism for controlling said actuator,
The second cylinder bore has a smaller diameter than the first cylinder bore;
Between the one end side of the drive shaft and the housing, a first thrust bearing that supports a thrust force directed to the one end side acting on the drive shaft is provided,
Between the other end side of the drive shaft and the housing, a second thrust bearing that supports a thrust force directed to the other end side acting on the drive shaft is provided,
The variable displacement swash plate compressor, wherein a second spring constant of the second thrust bearing is set larger than a first spring constant of the first thrust bearing. The housing is disposed on one end side of the drive shaft and has a first cylinder block formed with the first cylinder bore, and a second cylinder disposed on the other end side of the drive shaft and formed with the second cylinder bore. And having a block
On the one end side of the drive shaft, a first annular portion having an annular shape around the drive shaft center is formed,
On the other end side of the drive shaft, a second annular portion having an annular shape around the drive shaft center is formed,
The first thrust bearing is disposed between the first cylinder block and the first annular portion,
The range in which the first annular portion supports the first thrust bearing and the range in which the first cylinder block supports the first thrust bearing are shifted in the radial direction,
The second thrust bearing is disposed between the second cylinder block and the second annular portion,
2. The variable displacement swash plate type according to claim 1, wherein a range in which the second annular portion supports the second thrust bearing and a range in which the second cylinder block supports the second thrust bearing are displaced in the radial direction. Compressor. The housing is disposed on one end side of the drive shaft and has a first cylinder block formed with the first cylinder bore, and a second cylinder disposed on the other end side of the drive shaft and formed with the second cylinder bore. And having a block
On the one end side of the drive shaft, a first annular portion having an annular shape around the drive shaft center is formed,
On the other end side of the drive shaft, a second annular portion having an annular shape around the drive shaft center is formed,
The first thrust bearing is disposed between the first cylinder block and the first annular portion,
The second thrust bearing is disposed between the second cylinder block and the second annular portion,
The first thrust bearing includes one end side first race provided on the first cylinder block side, one end side second race provided on the first annular portion side, the one end side first race, and the one end side first race. A plurality of first rolling elements sandwiched between two races;
The second thrust bearing includes a first race on the other end side provided on the second cylinder block side, a second race on the other end side provided on the second annular portion side, the first race on the other end side, A plurality of second rolling elements sandwiched between the second race on the other end side,
3. The variable capacity type according to claim 1, wherein at least one of the other end side first race and the other end side second race is formed thicker than the one end side first race and the one end side second race. Swash plate compressor.   4. The variable displacement swash plate compressor according to claim 1, wherein an outer diameter of the second thrust bearing is set smaller than an outer diameter of the first thrust bearing. 5. The actuator is provided with a partition provided on the drive shaft, a connecting portion connected to the swash plate, a movable body movable in the direction of the drive axis in the swash plate chamber, the partition and the A control pressure chamber that is partitioned by the moving body and moves the moving body so that the inclination angle is increased by introducing the refrigerant from the discharge chamber,
5. The variable displacement swash plate compressor according to claim 1, wherein the actuator is located on the second cylinder bore side with respect to the swash plate in the swash plate chamber.

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