JP2005163772A - Variable displacement compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable displacement compressor facilitating machining of a hinge mechanism. <P>SOLUTION: The hinge mechanism 19 of this variable displacement compressor is composed of a support part 20 provided protrudedly on an end face 18b on a lag plate 17 side on a swash plate 18, a spherical part 23 provided protrudedly toward a rear side in the direction R of rotation of a driving shaft 16 in the support part 20, a roller 22 provided protrudedly toward a front side in the direction R of rotation in the support part 20, a first cam part 24 like a long channel provided on an end face 17a on a swash plate 18 side in the lag plate 17 to guide the spherical part 23, and a second cam part 25 provided on a front side in the direction R of rotation for the first cam part 24 on the same end face 17a as that of the first cam part 24 and having a cam face 25a guiding the roller 22. The second cam part 25 has such shape that opens the roller 22 onto a front side in the direction R of rotation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a variable capacity compressor used in a refrigeration circuit of a vehicle air conditioner, for example.

  In this type of variable capacity compressor, a cylinder bore is formed in a housing and a drive shaft is rotatably supported. A lug plate is fixed to the drive shaft so as to be integrally rotatable, and a swash plate is supported to be tiltable. A hinge mechanism is interposed between the lug plate and the swash plate. The piston accommodated in the cylinder bore so as to be able to reciprocate is anchored to the outer peripheral portion of the swash plate. Then, the rotation of the drive shaft is transmitted to the swash plate via the lug plate and the hinge mechanism, so that the piston is reciprocated to compress the refrigerant gas. Moreover, the stroke of the piston is changed by changing the inclination angle of the swash plate by the guidance of the hinge mechanism, so that the discharge capacity can be changed.

As the hinge mechanism, there is one disclosed in Patent Document 1, for example. That is, as shown in FIG. 7, link pins 103 having spherical portions 103a and 103b at both ends are provided on the end surface 101a of the swash plate 101 on the lug plate (thrust flange) 102 side. In the lug plate 102, a guide groove 102a for guiding one spherical portion 103a and a guide groove 102b for guiding the other spherical portion 103b are formed on the end surface 102c on the swash plate 101 side. The change in the inclination angle of the swash plate 101 is guided by the sliding of the spherical portions 103a, b of the link pin 103 on the inner surfaces of the guide grooves 102a, 102b.
JP 2001-289159 A (FIG. 3)

  However, of the pair of guide grooves 102a and 102b, one guide groove 102a located on the front side (left side in the drawing) of the rotation direction R of the lug plate 102 has a rotational force from the lug plate 102 to the swash plate 101. Not responsible for communication. The other guide groove 102b that bears the transmission of the rotational force is formed into a deep long groove shape, and the inner surface of the guide groove 102b is on the rear side (right side in the drawing) in the rotation direction R with respect to one spherical portion 103b that it guides. It is necessary to make them abut.

  However, one guide groove 102a that does not bear the transmission of rotational force is formed into a deep long groove shape, and the inner surface of the guide groove 102a faces the spherical portion 103a on the front side in the rotation direction R and the swash plate 101 side. The transmission of the rotational force from the swash plate 101 to the swash plate 101, the tilting of the swash plate 101 and the reception of the compression reaction force acting on the swash plate 101 from the piston are not essential. Therefore, there are many troublesome processing of long long grooves (guide grooves 102a, 102b), and there is a problem that it takes time to process the hinge mechanism.

  Further, as described above, in the one guide groove 102a that does not bear the transmission of the rotational force, the wall forming the inner surface of the guide groove 102a is positioned on the front side in the rotational direction R with respect to the spherical portion 103a. . Accordingly, the distance between the pair of spherical portions 103a and 103b and the distance between the pair of guide grooves 102a and 102b is reduced by the thickness of the wall, and the support of the swash plate 101 by the lug plate 102 becomes unstable.

  For this reason, for example, due to a compression reaction force that is biased against the swash plate 101 via the piston (the load center of the reaction force is indicated by an arrow X), the swash plate 101 is moved in a direction different from that when the discharge capacity is changed. It may be tilted. When the swash plate 101 is inclined in a direction different from that at the time of changing the discharge capacity, the contact state of the spherical portions 103a and 103b with the inner surfaces of the guide grooves 102a and 102b is changed from the design assumption, and the sliding resistance between the two is increased. Thus, there arises a problem that the capacity controllability of the variable capacity compressor is deteriorated.

  A first object of the present invention is to provide a variable capacity compressor in which a hinge mechanism can be easily processed. A second object is to provide a variable capacity compressor that achieves the first object and can prevent the cam plate from being inclined in a direction different from that at the time of changing the discharge capacity.

  In order to achieve the first object, a variable capacity compressor according to a first aspect of the present invention has the following configuration as a hinge mechanism. That is, a support portion projects from the end surface of the cam plate on the lug plate side. A first guide protrusion is provided on the support portion on the rear side in the rotational direction of the drive shaft. A second guide projection is projected from the support portion on the front side in the rotational direction of the drive shaft. A long groove-shaped first cam portion for guiding the first guide protrusion is provided on the end surface of the lug plate on the cam plate side. A second cam portion having a cam surface for guiding the second guide protrusion is provided on the same end surface as the first cam portion.

  In particular, according to a second aspect of the present invention, in the first aspect, the second cam portion has a shape that opens the second guide projection to the front side in the rotational direction of the drive shaft. In other words, the second cam portion that does not carry the transmission of the rotational force from the lug plate to the cam plate is not provided with a large wall that faces the second guide projection in the front side in the rotational direction of the drive shaft, The second cam portion does not have a deep long groove shape. Accordingly, troublesome deep long grooves are processed at one place of the first cam portion, and the hinge mechanism can be processed easily.

  In order to achieve the second object, the invention according to claim 3 is the invention according to claim 1 or 2, wherein the hinge mechanism is configured such that the first guide protrusion and the second guide protrusion have positions corresponding to the top dead center of the cam plate. It is arranged across. The second guide protrusion is further away from the top dead center corresponding position than the first guide protrusion.

  In other words, according to the first aspect of the present invention, the second cam portion does not have a large wall on the front side in the rotational direction of the drive shaft with respect to the second guide protrusion. Therefore, the second guide projection can be arranged away from the top dead center corresponding position by the amount of the wall, and the distance between the second guide projection and the first guide projection, and thus the first cam portion and the second cam. The space between the first and second portions can be widened, and the support of the cam plate by the lug plate can be stabilized. For this reason, it can suppress that this cam plate inclines in the direction different from the time of the change of discharge capacity by the compression reaction force which acts on a cam plate via a piston, for example.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, a shaft portion projects from the support portion on the front side in the rotational direction of the drive shaft. The second guide protrusion is composed of a rolling element that is rotatably supported by the shaft portion. Therefore, the second guide protrusion is smoothly slid by rolling on the cam surface of the second cam portion.

  According to a fifth aspect of the present invention, in the fourth aspect, an insertion hole is formed in the support portion, and a shaft body is inserted into the insertion hole. The shaft portion is provided by a second end portion of the shaft body protruding from the support portion. In the support portion, a spherical portion that forms a first guide protrusion is provided at the first end of the shaft that protrudes rearward in the rotational direction of the drive shaft. The diameter of the spherical portion is less than the inner diameter of the insertion hole.

  In this way, the spherical portion of the shaft body can pass through the insertion hole. Therefore, when the shaft body provided with the spherical portion is assembled to the cam plate, a procedure for inserting the shaft body from the first end side into the insertion hole of the support portion can be employed. That is, for example, when the diameter of the spherical portion is larger than the inner diameter of the insertion hole, in order to assemble the shaft body provided with the spherical portion to the cam plate, the shaft body is inserted into the support portion from the second end side. The only way is to insert it into the hole.

According to a sixth aspect of the present invention, in the fifth aspect, the spherical portion is integrally formed with the shaft body. Therefore, the number of parts constituting the hinge mechanism can be reduced.
According to a seventh aspect of the present invention, in the fifth or sixth aspect, the second end portion of the shaft body is integrally formed with a retaining member of the rolling element from the shaft body. Therefore, the number of parts constituting the hinge mechanism can be reduced.

  That is, for example, when the diameter of the spherical portion is equal to or larger than the inner diameter of the insertion hole, the shaft body provided with the spherical portion is assembled to the cam plate by inserting the shaft body from the second end side into the support portion. There is no choice but to adopt the procedure of inserting into the hole. In this case, if the retaining member of the rolling element is integrally formed with the second end portion, the second end portion is prevented from being inserted into the insertion hole. For this reason, it is necessary to configure the retaining member separately from the shaft body and to attach the retaining member to the shaft body after the shaft body is inserted into the insertion hole.

  However, according to the invention of claim 5 or 6, when the shaft body provided with the spherical portion is assembled to the cam plate, the shaft body is inserted from the first end side into the insertion hole of the support portion. The procedure to do can be adopted. Therefore, even if the shaft body is integrally formed with the retaining member, the retaining member does not prevent the shaft member from being inserted into the insertion hole.

  According to the first to seventh aspects of the present invention, the hinge mechanism can be easily processed, and the manufacturing cost of the variable capacity compressor can be reduced.

Hereinafter, an embodiment in which the present invention is embodied in a variable capacity compressor used in a refrigeration circuit of a vehicle air conditioner will be described with reference to FIGS.
FIG. 1 is a longitudinal sectional view of the variable capacity compressor (hereinafter simply referred to as a compressor) 10. In FIG. 1, the left side is the front of the compressor 10, and the right side is the rear of the compressor 10. As shown in FIG. 1, the housing of the compressor 10 includes a cylinder block 11, a front housing 12 joined and fixed to the front end of the cylinder block 11, and a valve / port forming body 13 at the rear end of the cylinder block 11. And a rear housing 14 joined and fixed.

  A crank chamber 15 is defined between the cylinder block 11 and the front housing 12 in the housing. A drive shaft 16 is rotatably supported between the cylinder block 11 and the front housing 12 so as to pass through the crank chamber 15. The drive shaft 16 is operatively connected to an engine (not shown) that is a travel drive source of the vehicle. The drive shaft 16 is supplied with power from the engine and is rotated in the direction of arrow R.

  A lug plate 17 having a substantially disk shape is fixed to the drive shaft 16 in the crank chamber 15 so as to be integrally rotatable. A swash plate 18 as a cam plate is accommodated in the crank chamber 15. The drive shaft 16 is inserted through an insertion hole 18a formed in the center of the swash plate 18. A hinge mechanism 19 is interposed between the lug plate 17 and the swash plate 18. The swash plate 18 can be rotated synchronously with the lug plate 17 and the drive shaft 16 by the hinge connection with the lug plate 17 via the hinge mechanism 19 and the support of the drive shaft 16 via the insertion hole 18a. The drive shaft 16 can be tilted with respect to the drive shaft 16 while being slid in the axis T direction.

  In the cylinder block 11, a plurality of cylinder bores 27 (only one is shown in the drawing) are formed around the axis T of the drive shaft 16 so as to penetrate in the front-rear direction (left-right direction in the drawing) at equal angular intervals. The single-headed piston 28 is accommodated in each cylinder bore 27 so as to be movable in the front-rear direction. The front and rear openings of the cylinder bore 27 are closed by the front end face of the valve / port forming body 13 and the piston 28, and a compression chamber 29 whose volume changes in accordance with the movement of the piston 28 in the front and rear direction is defined in the cylinder bore 27. Has been.

  The piston 28 is anchored to the outer periphery of the swash plate 18 via a pair of shoes 30. A suction chamber 31 and a discharge chamber 40 are respectively defined between the valve / port forming body 13 and the rear housing 14 in the housing. The valve / port forming body 13 is formed with a suction port 32 and a suction valve 33 so as to be positioned between the compression chamber 29 and the suction chamber 31. The valve / port forming body 13 is formed with a discharge port 34 and a discharge valve 35 so as to be positioned between the compression chamber 29 and the discharge chamber 40.

  The refrigerant in the suction chamber 31 (carbon dioxide is used in the present embodiment) moves from the top dead center position to the bottom dead center position side of each piston 28, thereby causing a suction port 32 and a suction valve 33. Through the compression chamber 29. The refrigerant gas sucked into the compression chamber 29 is compressed to a predetermined pressure by the movement from the bottom dead center position to the top dead center position side of the piston 28, and enters the discharge chamber 40 through the discharge port 34 and the discharge valve 35. And discharged.

  In the housing of the compressor 10, an extraction passage 36, an air supply passage 37, and a control valve 38 are provided. The extraction passage 36 connects the crank chamber 15 and the suction chamber 31. The air supply passage 37 connects the discharge chamber 40 and the crank chamber 15. In the middle of the air supply passage 37, a known control valve 38 made of an electromagnetic valve is disposed.

  By adjusting the opening of the control valve 38, the amount of high-pressure discharge gas introduced into the crank chamber 15 via the air supply passage 37 and the amount of gas discharged from the crank chamber 15 via the bleed passage 36 are obtained. The balance is controlled and the internal pressure of the crank chamber 15 is determined. In accordance with the change in the internal pressure of the crank chamber 15, the difference between the internal pressure of the crank chamber 15 and the internal pressure of the compression chamber 29 via the piston 28 is changed, and the inclination angle of the swash plate 18 (perpendicular to the axis T of the drive shaft 16). As a result, the stroke of the piston 28, that is, the discharge capacity of the compressor 10 is adjusted.

  For example, when the internal pressure of the crank chamber 15 is reduced, the inclination angle of the swash plate 18 is increased, the stroke of the piston 28 is increased, and the discharge capacity of the compressor 10 is increased. Conversely, when the internal pressure of the crank chamber 15 increases, the inclination angle of the swash plate 18 decreases, the stroke of the piston 28 decreases, and the discharge capacity of the compressor 10 decreases.

Next, the hinge mechanism 19 will be described.
As shown in FIGS. 1 to 3, the end surface 18 b on the lug plate 17 side of the swash plate 18 is near a top dead center corresponding position TDC (a portion where the piston 28 is positioned at the top dead center in the swash plate 18). The support part 20 protrudes toward the lug plate 17 side. The support portion 20 is a plane that bisects the tip edge of the support portion 20 in the center (parallel to the plane including the axis T of the drive shaft 16 and the top dead center corresponding position TDC and in plan view (see FIG. 2)). ) S is arranged to be shifted to the front side in the rotational direction R of the drive shaft 16 with respect to the top dead center corresponding position TDC.

  An insertion hole 20 a passes through the support portion 20 in a direction orthogonal to the center S. In the insertion hole 20a of the support portion 20, a link pin 21 as a shaft body is inserted and fixed by press-fitting. The link pin 21 has a second end portion (left end portion in FIG. 2) 21 b protruding from the support portion 20 to the front side in the rotation direction R, and a first end portion (right end portion in FIG. 2) 21 a is the support portion 20. Projecting to the rear side in the rotation direction R.

  The second end 21b of the link pin 21 is rotatably supported by a cylindrical roller 22 serving as a second guide projection and a rolling element by using the second end 21b as a shaft. ing. A circlip 26 that prevents the roller 22 from coming off from the link pin 21 is attached to the tip of the second end 21 b of the link pin 21 that protrudes from the roller 22. A spherical portion 23 as a first guide projection is integrally provided at the first end 21 a of the link pin 21.

  The roller 22 and the spherical portion 23 are arranged across the top dead center corresponding position TDC of the swash plate 18 in the rotational direction R. The roller 22 (specifically, the position M1 of the outer end surface of the roller 22) is more than the spherical portion 23 (specifically, the center M2 including the center point of the spherical portion 23 and made of a plane parallel to the center S of the support portion 20). It is separated from the top dead center corresponding position TDC. The shortest distance between the spherical portion 23 and the support portion 20 is longer than the shortest distance between the roller 22 and the support portion 20.

  In the lug plate 17, a relatively deep long groove-shaped first cam portion 24 for guiding the spherical portion 23 is provided on the end surface 17 a on the swash plate 18 side. The first cam portion 24 has a wall configuration in which the inner surface 24a faces the spherical portion 23 on the rear side in the rotation direction R, the swash plate 18 side, and the lug plate 17 side. The inner surface 24 a of the first cam portion 24 is inclined so as to be separated from the disk portion of the lug plate 17 as it approaches the drive shaft 16.

  A second cam portion 25 having a cam surface 25 a for guiding the roller 22 is provided on the end surface 17 a on the swash plate 18 side of the lug plate 17 on the front side in the rotation direction R with respect to the first cam portion 24. Yes. The cam surface 25 a of the second cam portion 25 is inclined so as to be separated from the disk portion of the lug plate 17 as it approaches the drive shaft 16. The 2nd cam part 25 does not have the wall which faces the roller 22 except the part which provides the cam surface 25a. That is, it can be said that the 2nd cam part 25 has the shape which open | releases the roller 22 to the front side of the rotation direction R. FIG.

  In the hinge mechanism 19, the rotational force is transmitted from the lug plate 17 to the swash plate 18 from the inner surface 24 a of the first cam portion 24 to the spherical portion 23. A compression reaction force acting on the swash plate 18 via the piston 28 (the load center of the reaction force is indicated by an arrow X) is mainly received by the cam surface 25a of the second cam portion 25 via the roller 22. .

  The tilt of the swash plate 18 when the discharge capacity of the compressor 10 is increased is changed while the roller 22 slides while rolling on the cam surface 25a of the second cam portion 25 in a direction away from the drive shaft 16, and The spherical portion 23 is guided by sliding on the inner surface 24 a of the first cam portion 24 in a direction away from the drive shaft 16. Conversely, the tilting of the swash plate 18 when the discharge capacity of the compressor 10 is decreased is changed while the roller 22 rolls on the cam surface 25a of the second cam portion 25 in a direction approaching the drive shaft 16. At the same time, the spherical portion 23 is guided by sliding on the inner surface 24 a of the first cam portion 24 in a direction approaching the drive shaft 16.

In the above embodiment, the following effects are produced.
(1) The second cam portion 25 of the hinge mechanism 19 has a shape that opens the roller 22 to the front side in the rotational direction R. That is, the second cam portion 25 that does not carry the transmission of the rotational force from the lug plate 17 to the swash plate 18 is not provided with a wall facing the roller 22 on the front side in the rotational direction R, and the second The cam portion 25 does not have a groove shape. Accordingly, troublesome deep long grooves are processed at one place of the first cam portion 24, and the hinge mechanism 19 can be processed easily. This leads to a reduction in manufacturing cost of the compressor 10.

  Further, since the second cam portion 25 does not have a wall around the cam surface 25a, the shape of the cam surface 25a can be freely set. Therefore, for example, even when the inclination angle of the swash plate 18 is changed, the dead volume of the compression chamber 29 (in other words, the clearance between the piston 28 at the top dead center position and the valve / port forming body 13) is kept constant. It is also easy to set the profile of the cam surface 25a to be maintained (for example, a delicate curved surface or a combination of a plurality of flat surfaces).

  Further, since the second cam portion 25 does not have a wall around the cam surface 25a, it is easy to adopt a configuration in which the tip of the second end portion 21b of the link pin 21 protrudes from the roller 22. . By making the tip of the second end 21 b protrude from the roller 22, it is possible to employ a configuration in which a circlip 26 that prevents the roller 22 from coming off is attached to the tip. Therefore, the assembly of the roller 22 to the link pin 21 is a simple operation of attaching the circlip 26 to the tip of the second end 21b after inserting the roller 22 into the second end 21b of the link pin 21. Become.

  (2) In the hinge mechanism 19, the roller 22 and the spherical portion 23 are disposed across the top dead center corresponding position TDC of the swash plate 18 in the rotation direction R. The roller 22 is further away from the top dead center corresponding position TDC than the spherical portion 23.

  That is, as described above, the second cam portion 25 does not have a wall on the front side in the rotation direction R with respect to the roller 22. Therefore, the roller 22 can be arranged away from the top dead center corresponding position TDC by the thickness of the wall. That is, the gap between the roller 22 (position M1) and the spherical portion 23 (center M2), and hence the gap between the first cam portion 24 and the second cam portion 25 can be widened, and the swash plate 18 is supported by the lug plate 17. Can be stabilized. For this reason, for example, the compression reaction force X acting on the swash plate 18 via the piston 28 can prevent the swash plate 18 from being inclined in a direction different from that at the time of changing the discharge capacity. For example, the capacity controllability of the compressor 10 can be improved.

  (3) The roller 22 is rotatably supported by the link pin 21. Accordingly, the roller 22 is smoothly slid by rolling on the cam surface 25a of the second cam portion 25, and for example, the capacity controllability of the compressor 10 can be improved.

  (4) The spherical portion 23 is separated from the support portion 20 rather than the roller 22. From another viewpoint, the width of the support portion 20 is narrower than the shortest distance between the roller 22 and the spherical portion 23. Accordingly, it is possible to reduce the thickness, that is, the weight of the support portion 20 that is unevenly distributed around the axis T, and to easily balance the weight (rotation balance) of the swash plate 18.

  The roller 22 is disposed closer to the support portion 20 than the spherical portion 23. By placing the roller 22 mainly responsible for receiving the compression reaction force X near the support portion 20, the stress based on the compression reaction force X acting on the link pin 21 via the roller 22 is reduced. The durability of the link pin 21 can be improved. It should be noted that the load acting on the spherical portion 23 due to the transmission of the rotational force is small, and therefore the stress based on the transmission of the rotational force acting on the link pin 21 is small. Therefore, even if the spherical portion 23 is separated from the support portion 20, there is no problem in the durability of the link pin 21.

  (5) Carbon dioxide is used as a refrigerant of the vehicle air conditioner. When the carbon dioxide refrigerant is used, the compression reaction force X acting on the swash plate 18 is large and the position where the compression reaction force X is applied is outside the swash plate 18 as compared with, for example, the case of using a chlorofluorocarbon refrigerant. Experiments have shown that it is located near the periphery.

  However, in the present embodiment, as described above, the roller 22 is disposed away from the top dead center corresponding position TDC, and the interval between the roller 22 (position M1) and the spherical portion 23 (center M2) is extended. The interval between the first cam portion 24 and the second cam portion 25 is widened. Therefore, even in the compressor 10 that handles the carbon dioxide refrigerant, the compression reaction force X acting on the swash plate 18 can be suitably received by the hinge mechanism 19 and the lug plate 17, and the swash plate 18 is discharged. Inclination in a direction different from that at the time of changing the capacity can be suppressed. That is, it can be said that the invention of claim 3 is particularly effective when applied to the compressor 10 that compresses the carbon dioxide refrigerant.

In addition, you may change the said embodiment as follows.
As shown in FIG. 4, the roller 22 of the hinge mechanism 19 has a spherical shape, and the cam surface 25 a of the second cam portion 25 has a concave curved surface shape along the spherical shape of the roller 22. In this case, the cam surface 25a has a groove shape extending in the sliding direction of the roller 22, which is much shallower than the first cam portion 24 (specifically, the cross-sectional shape). May be a semicircular arc or less), and does not hinder the ease of processing of the hinge mechanism 19 (the effect (1) of the above embodiment).

  As shown in FIG. 5, the spherical portion 23 of the hinge mechanism 19 is deleted, and the first end 21a of the link pin 21 is used as the first guide protrusion. A guide groove 24b is formed through the first cam portion 24 before and after the rotation direction R, and the first end 21a of the link pin 21 is inserted into the guide groove 24b. In this case, the rotational force is transmitted from the lug plate 17 to the swash plate 18 by direct contact between the front surface of the first cam portion 24 in the rotational direction R and the rear surface of the support portion 20 in the rotational direction R. It is done by contact.

  As is clear from FIG. 2, in the hinge mechanism 19 of the above embodiment, the spherical portion 23 of the link pin 21 has a diameter larger than the inner diameter of the insertion hole 20 a of the support portion 20. By changing this, for example, as shown in FIG. 6, the diameter of the spherical portion 23 is made smaller than the inner diameter of the insertion hole 20a. In this way, it is easy to cut out the spherical portion 23 in a part of the bar material that is the material of the link pin 21 and form the spherical portion 23 integrally with the link pin 21, and the components that constitute the hinge mechanism 19. Can be reduced.

  Further, the spherical portion 23 having a diameter smaller than the inner diameter of the insertion hole 20a can pass through the insertion hole 20a. That is, when the link pin 21 is assembled to the swash plate 18, a procedure of inserting the link pin 21 from the first end portion 21a side into the insertion hole 20a of the support portion 20 can be employed. Therefore, in the embodiment of FIG. 6, the flange portion 21 c that prevents the roller 22 from coming off is formed integrally with the end edge of the second end portion 21 b of the link pin 21. Therefore, the circlip 26 (see, for example, FIG. 2) separate from the link pin 21 that is necessary in the above embodiment can be deleted, and the number of parts constituting the hinge mechanism 19 can be reduced.

○ The cam surface 25a of the second cam portion 25 is formed in a convex curved shape in which the center in the width direction (rotational direction R) swells toward the roller 22 side.
The length of the roller 22 may be extended toward the support portion 20 and the width of the support portion 20 may be reduced by the extension of the roller 22.

  ○ The spherical portion 23 is rotatably supported by the link pin 21, and the spherical portion 23 is slid on the inner surface 24 a of the first cam portion 24 when the inclination angle of the swash plate 18 is changed. That is, let the first guide protrusion be a rolling element.

  In the above embodiment and the modes of FIGS. 4 to 6, the rolling element (roller 22) is used as the second guide protrusion of the hinge mechanism 19. This is changed, and the second guide protrusion is fixed to the support portion so as not to rotate.

○ Do not shift the support portion 20 (specifically, the center S) of the hinge mechanism 19 with respect to the top dead center corresponding position TDC.
○ The roller 22 and the spherical portion 23 are arranged at the same distance from the support portion 20.

  In the above embodiment and the modes of FIGS. 4 to 6, the swash plate type variable displacement compressor 10 is embodied. By changing this, the present invention is embodied in a wobble type variable capacity compressor.

  In the above embodiment and the modes shown in FIGS. 4 to 6, carbon dioxide is used as the refrigerant of the vehicle air conditioner. Change this and use chlorofluorocarbon as a refrigerant. That is, the present invention is embodied in a variable capacity compressor that handles CFC refrigerant.

Next, the technical idea that can be grasped from the above embodiment and other examples will be described below.
(1) The variable capacity compressor according to any one of claims 4 to 7, wherein a tip end of the shaft portion protrudes from the rolling element. In this way, it is possible to provide a stopper for preventing the rolling element from coming off from the shaft part at the tip of the shaft part protruding from the rolling element, and the assembly of the rolling element to the shaft part is facilitated.

(2) The variable according to any one of claims 1 to 7, or the technical idea (1), wherein the second guide protrusion is disposed closer to the support than the first guide protrusion. Capacity compressor.
(3) The gas is a refrigerant of an air conditioner, and carbon dioxide is used as the refrigerant. The variable according to any one of claims 1 to 7, or the technical idea (1) or (2). Capacity compressor.

The longitudinal section showing the variable capacity compressor of one embodiment. The top view which shows the hinge mechanism vicinity. The side view which shows the hinge mechanism vicinity. The top view which shows the hinge mechanism vicinity of another example. The top view which shows the hinge mechanism vicinity of another example. The top view which shows the hinge mechanism vicinity of another example. The cross-sectional view which shows a prior art.

Explanation of symbols

  R: rotational direction, TDC: position corresponding to top dead center, 10: variable capacity compressor, 16 ... drive shaft, 17 ... lug plate (a ... end face on the swash plate side), 18 ... swash plate as cam plate (b ... Lug plate side end surface), 19 ... hinge mechanism, 20 ... support portion (a ... insertion hole), 21 ... link pin as shaft body (a ... first end portion, b ... second end portion as shaft portion) 22 ... Roller as second guide protrusion, 23 ... Spherical part as first guide protrusion, 24 ... First cam part, 25 ... Second cam part (a ... Cam surface), 26 ... Stopping Flange part, 27 ... cylinder bore, 28 ... piston.

Claims (7)

A cylinder bore is formed in the housing and a drive shaft is rotatably supported. A lug plate is coupled to the drive shaft so as to be integrally rotatable and a cam plate is supported to be tiltable. A hinge mechanism is interposed between the cam plate, a piston accommodated reciprocally in the cylinder bore is moored to the cam plate, and rotation of the drive shaft causes the lug plate and the hinge mechanism to move. And the piston is reciprocated to compress the gas, and the cam plate changes the tilt angle by the guidance of the hinge mechanism, so that the stroke of the piston is changed. In the variable capacity compressor that is changed and can change the discharge capacity,
The hinge mechanism includes a support portion protruding from an end surface of the cam plate on the lug plate side, a first guide protrusion protruding from the support portion on the rear side in the rotation direction of the drive shaft, A second guide projection protruding from the front of the drive shaft in the rotation direction of the support shaft and a long groove-shaped second guide provided on the end surface of the lug plate on the cam plate side for guiding the first guide projection. A variable capacity compressor comprising: a cam portion; and a second cam portion provided on the same end surface as the first cam portion and having a cam surface for guiding the second guide protrusion.   2. The variable capacity compressor according to claim 1, wherein the second cam portion has a shape that opens the second guide protrusion to the front side in the rotation direction of the drive shaft.   In the hinge mechanism, the first guide protrusion and the second guide protrusion are disposed across the position corresponding to the top dead center of the cam plate, and the second guide protrusion is more than the first guide protrusion. 3. The variable capacity compressor according to claim 1, wherein the variable displacement compressor is further away from the top dead center corresponding position.   A shaft portion projects from the support portion on the front side in the rotation direction of the drive shaft, and the second guide projection portion is formed of a rolling element that is rotatably supported by the shaft portion. The variable capacity compressor according to claim 3.   An insertion hole is formed in the support portion, a shaft body is inserted into the insertion hole, and the shaft portion is provided by a second end portion of the shaft body protruding from the support portion. A spherical portion forming the first guide protrusion is provided at a first end portion of the shaft body protruding rearward in the rotation direction of the drive shaft, and the diameter of the spherical portion is the inner diameter of the insertion hole. The variable capacity compressor according to claim 4, which is less than 5.   The variable capacity compressor according to claim 5, wherein the spherical portion is integrally formed with the shaft body.   The variable capacity compressor according to claim 5 or 6, wherein a retaining member of the rolling element from the shaft body is integrally formed at the second end portion of the shaft body.

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