JP2006132446A - Variable displacement compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable displacement compressor in which lubricating oil having flowed out of a control pressure chamber holding a cam body can be easily returned to the control pressure chamber. <P>SOLUTION: A sleeve 48 is slidably fit on the periphery of a rotation shaft 18 between a rotation support 21 and a swash plate 22. At the time when the angle of inclination of the swash plate 22 is decreasing, the sleeve 48 follows the inclination of the swash plate 22 by the spring force of a compression spring 49. At the time when the angle of inclination of the swash plate 22 is increasing, the sleeve 48 is pushed to the rotation support 21 against the spring force of the compression spring 49. An opening 482 is formed in the sleeve 48. In the rotation shaft 18, a 1st conduction path 46 , and a 2nd conduction path 47 are formed. The sleeve 48 can open/close the 2nd conduction path 47. When the opening 482 has communicated with the 2nd conduction path 47, an in-shaft path 44 communicates with the control-pressure chamber 121 through the 2nd conduction path 47 and the opening 482. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a variable capacity compressor in which a piston is interlocked with the rotation of a rotary shaft through a cam body that rotates integrally with the rotary shaft.

In the variable displacement compressors disclosed in Patent Documents 1 and 2, a sleeve slidably fitted to the rotation shaft slides along the rotation shaft in conjunction with the tilting of the cam body.
In the variable displacement compressor disclosed in Patent Document 1, a vertical hole (intra-shaft passage) is formed along the axis in the rotation shaft, and a crank chamber (control pressure chamber) that houses a rotation drive plate (cam body). A horizontal hole formed in the peripheral surface of the inner rotary shaft communicates with the vertical hole. The refrigerant in the crank chamber can flow out to the suction chamber via the vertical hole and the horizontal hole. The opening of the side hole is adjusted by the position of the sleeve. The opening of the horizontal hole is reduced as the tilt angle of the rotary drive plate is reduced. When the tilt angle of the rotary drive plate is small, the pressure increase in the crank chamber is promoted.

  In the variable displacement compressor disclosed in Patent Document 2, an axial hole (intra-shaft passage) is formed along the axis in the rotating shaft, and the diameter formed on the peripheral surface in the crank chamber that houses the cam body. The directional hole is in communication with the axial hole. A space for accommodating the lip seal is communicated with the crank chamber, and the space is communicated with the axial hole through a communication passage formed on the peripheral surface of the rotating shaft. When the cam body has a minimum inclination angle, the sleeve closes the radial hole, and the refrigerant in the crank chamber flows out to the suction chamber via the communication path and the axial hole. When the tilt angle of the cam body is large, the radial hole is opened, and the refrigerant in the crank chamber flows out to the suction chamber via the radial hole and the axial hole.

In the variable displacement compressors in Patent Documents 1 and 2, the in-shaft passage provided in the rotating shaft serves as a passage for adjusting the pressure in the crank chamber by discharging the refrigerant in the crank chamber to the suction chamber.
JP-A-11-62824 JP 2000-297746 A

  Although the lubricating oil in the crank chamber tends to flow out from the crank chamber together with the refrigerant to the in-shaft passage in the rotating shaft, it is desirable to keep the lubricating oil in the crank chamber without sending it to the suction chamber side as much as possible. This is important in increasing the efficiency of heat exchange by reducing the adhesion of lubricating oil to the heat exchanger in the refrigerant circuit outside the compressor.

  An object of the present invention is to provide a variable displacement compressor that can easily reduce lubricating oil flowing out from a control pressure chamber that houses a cam body to the control pressure chamber.

  In the present invention, the piston is interlocked with the rotation of the rotating shaft via a cam body that rotates integrally with the rotating shaft, and the discharge pressure is supplied via a supply passage to a control pressure chamber that accommodates the cam body with a variable tilt angle. In addition to supplying the refrigerant in the region, the refrigerant in the control pressure chamber is discharged to the suction pressure region through the discharge passage, and the pressure in the control pressure chamber is regulated. The present invention is directed to a variable displacement compressor whose discharge capacity is controlled by changing an inclination angle. The invention of claim 1 is a part of the discharge passage, and extends in the axial direction of the rotary shaft so as to extend in the axial direction of the rotary shaft. An in-shaft passage provided; a first introduction passage for communicating the control pressure chamber and the in-shaft passage; a second introduction passage for communicating the control pressure chamber and the in-shaft passage; It moves in the axial direction of the rotating shaft in conjunction with tilting, and the first introduction A movable body capable of opening and closing the passage and the second introduction passage, wherein the first introduction passage and the second introduction passage are provided at positions separated from each other in the axial direction of the rotation shaft. And

Lubricating oil in the shaft passage can flow into the control pressure chamber by centrifugal force from the first introduction passage in the open state or the second introduction passage in the open state.
Since there are the first introduction passage and the second introduction passage, the degree of freedom in selecting the open / close state of the first introduction passage and the second introduction passage according to the position of the moving body is increased. That is, when the discharge capacity is minimum, the first introduction path and the second introduction path are closed, and when the discharge capacity is maximum or in the middle, either the first introduction path or the second introduction path is opened. A configuration such as arranging the first introduction passage and the second introduction passage can be selected. Alternatively, it is possible to select a configuration in which the first introduction passage and the second introduction passage are arranged so that both the first introduction passage and the second introduction passage are opened when the discharge capacity is maximum. Such a high degree of freedom of selection makes it possible to employ a configuration in which the lubricating oil that has flowed out of the control pressure chamber into the shaft passage can be easily returned to the control pressure chamber.

  In a preferred example, the movable body can open both the first introduction passage and the second introduction passage at the same time, and the movable body includes the first introduction passage and the second introduction passage. When both are opened at the same time, the cam body has an intermediate tilt angle.

  When the cam body is at an intermediate tilt angle, for example, a case where the first introduction passage is disposed at a position where oil inflow from the first introduction passage into the control pressure chamber is blocked by the cam body is assumed. Even in such a case, since the second introduction passage is open, the lubricating oil in the in-shaft passage can flow into the control pressure chamber from the second introduction passage, so that the amount of oil stored in the control pressure chamber can be increased. is there.

In a preferred example, when the inclination angle of the cam body is the maximum inclination angle, the first introduction passage is opened and the second introduction passage is closed by the moving body.
When the discharge capacity is maximum, the first introduction passage is open, and the lubricating oil in the in-shaft passage can be returned to the control pressure chamber via the first introduction passage.

In a preferred example, when the inclination angle of the cam body is the maximum inclination angle, both the first introduction passage and the second introduction passage are opened.
When the discharge capacity is the maximum, both the first introduction passage and the second introduction passage are open, and the lubricating oil in the shaft passage is reduced to the control pressure chamber as compared with the case where the second introduction passage is closed. easy.

In a preferred example, a shaft seal device for preventing refrigerant leakage from the control pressure chamber along the peripheral surface of the rotary shaft is provided, and a normally open passage accommodates the shaft seal device in the rotary shaft. And when the first introduction passage and the second introduction passage are closed, the refrigerant in the control pressure chamber passes through the normally open passage. Then flows out into the in-shaft passage.

  The normally open passage is part of a passage for adjusting the pressure in the control pressure chamber by discharging the refrigerant in the control pressure chamber to the suction pressure region. In this case, it is preferable that the first introduction passage and the second introduction passage are closed by the moving body when the inclination angle of the cam body is the minimum inclination angle. In this way, when the discharge capacity is minimum, the refrigerant in the control pressure chamber flows out to the in-shaft passage only through the normally open passage, and the shaft seal device is driven by the lubricating oil flowing together with the refrigerant through the normally open passage. Fully lubricated.

In a preferred example, the variable capacity compressor is a clutchless compressor capable of obtaining a rotational driving force from an external drive source without a clutch and stopping refrigerant circulation in an external refrigerant circuit.
A clutchless compressor is suitable as an application target of the present invention.

  The variable displacement compressor of the present invention has an excellent effect that the lubricating oil that has flowed out of the control pressure chamber that houses the cam body can be easily returned to the control pressure chamber.

Hereinafter, a first embodiment in which the present invention is embodied in a clutchless variable displacement compressor will be described with reference to FIGS.
As shown in FIG. 1, a front housing 12 is connected to the front end of the cylinder block 11. A rear housing 13 is connected to the rear end of the cylinder block 11 via a valve plate 14, valve forming plates 15 and 16, and a retainer forming plate 17. The cylinder block 11, the front housing 12, and the rear housing 13 constitute an entire housing of the variable displacement compressor 10.

  A rotating shaft 18 is supported on the front housing 12 and the cylinder block 11 that form the control pressure chamber 121. The rotary shaft 18 is rotatably supported by a plain bearing 19 fitted in the through hole 122 of the front housing 12 and a plain bearing 20 fitted in the through hole 112 of the cylinder block 11. The rotating shaft 18 projecting outside from the control pressure chamber 121 obtains driving force from the vehicle engine E which is an external driving source.

  A rotary support 21 is fixed to the rotary shaft 18, and a swash plate 22 as a cam body is supported so as to be slidable and tiltable in the axial direction of the rotary shaft 18. The rotary shaft 18 is passed through a through hole 223 provided in the center of the swash plate 22, and the swash plate 22 can slide on the outer peripheral surface of the rotary shaft 18 through the peripheral wall of the through hole 223. .

  As shown in FIG. 4, a pair of arms 212 and 213 project from the rotary support 21 toward the swash plate 22, and a pair of protrusions 221 and 222 project toward the rotary support 21. Projecting. The protrusions 221 and 222 are inserted into a recess 214 formed between the pair of arms 212 and 213. The protrusions 221 and 222 can move in the recess 214 while being sandwiched between the pair of arms 212 and 213. The bottom of the recess 214 is formed on the cam surface 211, and the tip portions of the protrusions 221 and 222 can slidably contact the cam surface 211. The swash plate 22 can be tilted in the axial direction of the rotary shaft 18 and can rotate integrally with the rotary shaft 18 by the linkage of the projections 221 and 222 sandwiched between the pair of arms 212 and 213 and the cam surface 211. Tilt of the swash plate 22 is guided by the slide guide relationship between the cam surface 211 and the protrusions 221 and 222 and the slide support action of the rotating shaft 18. The pair of arms 212, 213 and the protrusions 221, 222 are provided between the swash plate 22 and the rotary support 21, can tilt the swash plate 22 with respect to the rotary support 21, and swash plate 22 from the rotary shaft 18. The hinge mechanism 23 is connected so as to be able to transmit torque.

  If the radius center part of the swash plate 22 moves to the rotation support body 21 side, the inclination angle of the swash plate 22 increases. The maximum inclination angle of the swash plate 22 is regulated by the contact between the rotary support 21 and the swash plate 22. The minimum inclination angle of the swash plate 22 is regulated by contact with the position regulating ring 50 fitted to the outer peripheral surface of the rotating shaft 18. The swash plate 22 shown by the solid line in FIG. 1 is in the maximum tilt state, and the swash plate 22 shown by the chain line is in the minimum tilt state. The minimum inclination angle of the swash plate 22 is slightly larger than 0 °.

  Pistons 24 are accommodated in a plurality of cylinder bores 111 penetrating the cylinder block 11. The rotational movement of the swash plate 22 is converted into the back-and-forth reciprocating movement of the piston 24 via the shoe 25, and the piston 24 reciprocates in the cylinder bore 111. That is, the piston 24 is interlocked with the rotation of the rotary shaft 18 through the swash plate 22 that rotates integrally with the rotary shaft 18.

  A suction chamber 131 and a discharge chamber 132 are defined in the rear housing 13. A suction port 141 is formed in the valve plate 14, the valve forming plate 16 and the retainer forming plate 17. A discharge port 142 is formed in the valve plate 14 and the valve forming plate 15. A suction valve 151 is formed on the valve forming plate 15, and a discharge valve 161 is formed on the valve forming plate 16. The refrigerant in the suction chamber 131, which is the suction pressure region, flows into the cylinder bore 111 by pushing the suction valve 151 away from the suction port 141 by the backward movement of the piston 24 (movement from the right side to the left side in FIG. 1). The gaseous refrigerant that has flowed into the cylinder bore 111 is discharged from the discharge port 142 to the discharge chamber 132, which is a discharge pressure region, by the forward movement of the piston 24 (moving from the left side to the right side in FIG. 1). Is done. The discharge valve 161 abuts on the retainer 171 on the retainer forming plate 17 and the opening degree is regulated.

  A thrust bearing 37 is interposed between the rotary support 21 and the front housing 12. The thrust bearing 37 receives a discharge reaction force acting on the rotary support 21 from the cylinder bore 111 via the piston 24, the shoe 25, the swash plate 22 and the hinge mechanism 23.

  A thrust bearing 42 and a compression spring 43 are interposed between the inner end surface of the rotary shaft 18 and the valve forming plate 15 in the shaft passage hole 112. The compression spring 43 in the accommodation hole 113 provided in the shaft through hole 112 presses the thrust bearing 42 against the rotary shaft 18. The spring force of the compression spring 43 is transmitted to the front housing 12 through the thrust bearing 42, the rotary shaft 18, the rotary support 21 and the thrust bearing 37. That is, the spring force of the compression spring 43 serves as a preload that suppresses rattling in the axial direction of the rotary shaft 18.

  A gap 39 exists between the rotary support 21 and the front housing 12. A lip seal type shaft seal device 38 is interposed between the front housing 12 and the rotary shaft 18. The accommodating chamber 40 that accommodates the shaft seal device 38 communicates with the gap 39 through the passage 41.

  An in-axis passage 44 is formed in the rotating shaft 18 along the central axis 181 of the rotating shaft 18. The in-shaft passage 44 communicates with the housing hole 113, and the housing hole 113 is connected to the suction chamber 131 through a throttle hole 143 penetrating the valve plate 14, the valve forming plates 15, 16 and the retainer forming plate 17. Communicate.

  A normally open passage 45 is formed in the rotary shaft 18 so as to communicate with the accommodation chamber 40 and the in-shaft passage 44. Further, the first introduction passage 46 and the second introduction passage 47 are formed in the rotation shaft 18 so as to open to the outer peripheral surface of the rotation shaft 18 in the control pressure chamber 121. Both the first introduction passage 46 and the second introduction passage 47 communicate with the in-shaft passage 44. As shown in FIG. 2, a plurality (four in this embodiment) of first introduction passages 46 are provided at the same position in the direction of the central axis 181 of the rotation shaft 18. As shown in FIG. 3, a plurality of (four in the present embodiment) second introduction passages 47 are provided at the same position in the direction of the central axis 181 of the rotation shaft 18. The first introduction passage 46 and the second introduction passage 47 are provided at positions separated from each other in the direction of the central axis 181 of the rotation shaft 18.

  As shown in FIG. 1, the first introduction passage 46 and the second introduction passage 47 are provided in this order so as to be separated from the position restricting ring 50 side to the rotary support 21 side in the direction of the central axis 181 of the rotary shaft 18. It has been. The opening 461 of the first introduction passage 46 on the outer peripheral surface of the rotary shaft 18 is provided at a position outside the range surrounded by the peripheral wall of the shaft through hole 223 of the swash plate 22 when the swash plate 22 is in the maximum inclination angle state. Yes.

  As shown in FIGS. 1 and 5A, a sleeve 48 is slidably fitted on the outer periphery of the rotary shaft 18 between the rotary support 21 and the swash plate 22. A flange 481 is formed on the outer periphery of the sleeve 48 as a movable body so as to be in contact with the swash plate 22. A coil-shaped compression spring 49 is interposed between the flange 481 and the rotary support 21. The compression spring 49 urges the sleeve 48 toward the swash plate 22, and the sleeve 48 is in contact with the swash plate 22 by the spring force of the compression spring 49. When the inclination angle of the swash plate 22 decreases, the sleeve 48 follows the inclination of the swash plate 22 by the spring force of the compression spring 49. When the inclination angle of the swash plate 22 increases, the sleeve 48 is pushed toward the rotary support 21 against the spring force of the compression spring 49.

  An opening 482 is formed in the sleeve 48. The opening 482 can communicate with at least one of the plurality of second introduction passages 47. When the opening 482 communicates with the second introduction passage 47 (when the opening 471 of the second introduction passage 47 on the outer peripheral surface of the rotating shaft 18 is not closed by the sleeve 48), the in-axis passage 44 is The control pressure chamber 121 communicates with the introduction passage 47 and the opening 482.

  As shown in FIG. 1, the suction passage 26 for introducing the refrigerant into the suction chamber 131 and the discharge passage 27 for discharging the refrigerant from the discharge chamber 132 are connected by an external refrigerant circuit 28. On the external refrigerant circuit 28, a heat exchanger 29 for removing heat from the refrigerant, an expansion valve 30, and a heat exchanger 31 for transferring ambient heat to the refrigerant are interposed. The expansion valve 30 controls the flow rate of the refrigerant according to the change in the gas temperature on the outlet side of the heat exchanger 31.

  A check valve 32 is interposed on the discharge passage 27. The check valve 32 includes a cylindrical valve housing 33, a cylindrical valve body 34 slidably accommodated in the valve housing 33, and a cylindrical spring seat fitted and fixed in the valve housing 33. 35, and a compression spring 36 interposed between the spring seat 35 and the valve body 34. A valve hole 331 is formed in the end wall of the valve housing 33. The valve body 34 can be disposed at a seating position where the valve hole 331 is closed in contact with the end wall of the valve housing 33 and at an open position where the valve hole 331 is opened away from the end wall of the valve housing 33. The compression spring 36 biases the valve body 34 toward the seating position where the valve hole 331 is closed.

  A bypass port 332 is formed in the peripheral wall of the valve housing 33, and an outflow port 351 is formed in the end wall of the spring seat 35. A through hole 341 is provided through the peripheral wall of the tubular valve body 34. When the valve body 34 is in the open position shown in FIG. 1, the refrigerant in the discharge chamber 132 passes through the valve hole 331, the bypass port 332, the communication port 341, the inside of the cylinder of the valve body 34, and the outflow port 351. It flows out to the refrigerant circuit 28. When the valve body 34 is in the seating position, the valve hole 331 is closed and the refrigerant in the discharge chamber 132 does not flow out to the external refrigerant circuit 28.

  The discharge chamber 132 and the control pressure chamber 121 are connected by the supply passage 51. The refrigerant in the discharge chamber 132 is supplied to the control pressure chamber 121 through the supply passage 51. The refrigerant in the control pressure chamber 121 passes through the gap 39, the passage 41, the storage chamber 40, the normally open passage 45, or through the first introduction passage 46 and the second introduction passage 47 to the shaft passage 44. leak. The refrigerant in the in-shaft passage 44 flows out to the suction chamber 131 through the accommodation hole 113 and the throttle hole 143.

  A throttle 281 is provided in the middle of the external refrigerant circuit upstream of the heat exchanger 29 (hereinafter referred to as external refrigerant circuits 28A and 28B). The external refrigerant circuit 28A is upstream of the throttle 281 and the external refrigerant circuit 28B is downstream of the throttle 281.

  An electromagnetic capacity control valve 52 is assembled on the supply passage 51. The fixed iron core 54 constituting the solenoid 53 of the capacity control valve 52 attracts the movable iron core 56 based on excitation by supplying current to the coil 55. A biasing spring 57 is interposed between the fixed iron core 54 and the movable iron core 56. The movable iron core 56 is urged in the direction away from the fixed iron core 54 by the spring force of the urging spring 57. The solenoid 53 receives current supply control (duty ratio control in this embodiment) of the control computer C. A transmission rod 58 is fixed to the movable iron core 56. A valve body 581 is integrally formed with the transmission rod 58. The valve body 581 opens and closes the valve hole 61 that is a part of the supply passage 51.

In the capacity control valve 52, a first pressure sensing chamber 65 and a second pressure sensing chamber 66 are partitioned with a bellows 67 interposed therebetween. The transmission rod 58 is interlocked with the bellows 67.
The first pressure sensing chamber 65 communicates with the external refrigerant circuit 28A upstream of the throttle 281 via the pressure introduction passage 68A, and the second pressure sensing chamber 66 is located more than the throttle 281 via the pressure introduction passage 68B. It communicates with the downstream external refrigerant circuit 28B. The pressure in the first pressure sensing chamber 65 and the pressure in the second pressure sensing chamber 66 are opposed via a bellows 67.

  If refrigerant flows are generated in the external refrigerant circuits 28A and 28B, the pressure of the external refrigerant circuit 28A upstream of the throttle 281 is lower than the pressure of the external refrigerant circuit 28B downstream of the throttle 281 and upstream of the heat exchanger 29. Also grows. When the rotational speed of the rotary shaft 18 increases and the refrigerant flow rate in the external refrigerant circuits 28A and 28B (discharge pressure region) increases, the difference in pressure before and after the throttle 281 increases. If it does so, the valve opening degree in the capacity | capacitance control valve 52 will become large, and the refrigerant | coolant amount supplied to the control pressure chamber 121 from the discharge chamber 132 will increase. As a result, the pressure in the control pressure chamber 121 rises, the inclination angle of the swash plate 22 shifts to the minimum inclination side, and the discharge capacity decreases.

  When the rotational speed of the rotary shaft 18 decreases and the refrigerant flow rate in the external refrigerant circuits 28A and 28B (discharge pressure region) decreases, the difference in pressure before and after the throttle 281 decreases. When the pressure difference before and after the restriction 281 increases, the pressure difference between the pressure sensitive chambers 65 and 66 increases, and when the pressure difference before and after the restriction 281 decreases, the pressure difference between the pressure sensitive chambers 65 and 66 decreases. If it does so, the valve opening degree in the capacity | capacitance control valve 52 will become small, and the refrigerant | coolant amount supplied to the control pressure chamber 121 from the discharge chamber 132 will decrease. As a result, the pressure in the control pressure chamber 121 decreases, the inclination angle of the swash plate 22 shifts to the maximum inclination angle side, and the discharge capacity increases. The differential pressure between the pressure sensing chambers 65 and 66 becomes a force for urging the transmission rod 58 toward the direction in which the valve body 581 is separated from the valve hole 61.

  The pressure sensitive chambers 65 and 66 and the bellows 67 have a differential pressure between the pressure of the external refrigerant circuit 28A upstream of the throttle 281 and the pressure of the external refrigerant circuit 28B downstream of the throttle 281 and upstream of the heat exchanger 29. A sensitive pressure sensing means 69 is constructed. The degree of opening and closing of the valve hole 61 is determined by the balance of the electromagnetic force generated by the solenoid 53, the spring force of the biasing spring 57, and the biasing force of the pressure sensing means 69.

  The control computer C that performs current supply control (duty ratio control) on the solenoid 53 of the capacity control valve 52 supplies current to the solenoid 53 when the air conditioner operation switch 70 is turned on, and turns off current when the air conditioner operation switch 70 is turned off. Stop supplying. A room temperature setter 71 and a room temperature detector 72 are signal-connected to the control computer C. When the air conditioner operation switch 70 is in the ON state, the control computer C controls the solenoid 53 based on the temperature difference between the target room temperature set by the room temperature setter 71 and the detected room temperature detected by the room temperature detector 72. Control the current supply. The valve opening degree in the valve hole 61 decreases as the duty ratio increases.

  When the duty ratio becomes zero, the valve opening in the capacity control valve 52 is maximized, and the inclination angle of the swash plate 22 is minimized. The discharge pressure when the swash plate tilt angle is at a minimum is low, and the spring force of the compression spring 36 at the check valve 32 is such that the pressure upstream of the check valve 32 when the swash plate tilt angle is at the minimum is downstream of the check valve 32. It is set to be less than the sum of the pressure on the side and the spring force of the compression spring 36. Therefore, when the inclination angle of the swash plate 22 is minimized, the valve element 34 in the check valve 32 closes the valve hole 331 and the refrigerant circulation in the external refrigerant circuit 28 is stopped. This refrigerant circulation stop state is a stop state of the heat load reducing action.

  Since the minimum inclination angle of the swash plate 22 is slightly larger than 0 °, the discharge from the cylinder bore 111 to the discharge chamber 132 is performed even when the swash plate inclination angle is minimum. The refrigerant discharged from the cylinder bore 111 to the discharge chamber 132 flows into the control pressure chamber 121 through the supply passage 51. The refrigerant in the control pressure chamber 121 flows out into the suction chamber 131 through the in-shaft passage 44, and the refrigerant in the suction chamber 131 is sucked into the cylinder bore 111 and discharged into the discharge chamber 132. That is, when the inclination angle of the swash plate is minimum, the discharge chamber 132 that is the discharge pressure region, the supply passage 51, the control pressure chamber 121, the in-shaft passage 44, the suction chamber 131 that is the suction pressure region, and the circulation passage that passes through the cylinder bore 111 are present. Made in the compressor. A pressure difference is generated between the discharge chamber 132, the control pressure chamber 121, and the suction chamber 131. Accordingly, the refrigerant gas circulates in the circulation passage, and the lubricating oil flowing together with the refrigerant lubricates the inside of the compressor.

  When the current is supplied to the solenoid 59, the valve opening of the capacity control valve 52 is reduced, and the pressure in the control pressure chamber 121 is reduced. Accordingly, the inclination angle of the swash plate 22 increases from the minimum inclination angle. When the inclination angle of the swash plate 22 increases from the minimum inclination angle, the discharge pressure increases, and the pressure on the upstream side of the check valve 32 exceeds the sum of the pressure on the downstream side of the check valve 32 and the spring force of the compression spring 36. Therefore, when the inclination angle of the swash plate 22 is larger than the minimum inclination angle, the valve hole 331 in the check valve 32 is opened, and the refrigerant in the discharge chamber 132 flows out to the external refrigerant circuit 28. The refrigerant that has flowed into the external refrigerant circuit 28 returns to the suction chamber 131.

  When the duty ratio is not zero and the rotational speed of the rotary shaft 18 changes, the valve opening degree in the capacity control valve 52 changes and the inclination angle of the swash plate 22 changes. In the present embodiment, the inclination angle of the swash plate 22 is maximized when the rotation speed of the rotation shaft 18 is low, and the inclination angle of the swash plate 22 is minimum and maximum when the rotation speed of the rotation shaft 18 is high. It becomes an intermediate tilt angle between the tilt angles.

  As shown in FIG. 5A, when the inclination angle of the swash plate 22 is maximum (when the discharge capacity is maximum), the opening 482 of the sleeve 48 is in a position away from the opening 471 of the second introduction passage 47. The sleeve 48 closes the second introduction passage 47. Therefore, the refrigerant in the control pressure chamber 121 flows out from the normally open passage 45 and the first introduction passage 46 into the shaft passage 44. A part of the lubricating oil flowing together with the refrigerant in the control pressure chamber 121 enters the accommodation chamber 40 through the gap 39 and the passage 41, and the shaft seal device 38 is lubricated. The lubricating oil in the in-shaft passage 44 can flow into the control pressure chamber 121 from the first introduction passage 46 by the centrifugal force accompanying the rotation of the rotating shaft 18.

  As shown in FIG. 5B, in a state where the opening 482 of the sleeve 48 overlaps the opening 471 of the second introduction passage 47, the swash plate 22 has an intermediate inclination angle between the maximum inclination angle and the minimum inclination angle. Is in a state. In the intermediate tilt state, some of the first introduction passages 46 are surrounded by the peripheral wall of the shaft through hole 223 of the swash plate 22. The lubricating oil in the in-shaft passage 44 can flow into the control pressure chamber 121 from the second introduction passage 47 by the centrifugal force accompanying the rotation of the rotating shaft 18. That is, the lubricating oil in the in-shaft passage 44 can flow into the control pressure chamber 121 even when the inclination angle of the swash plate 22 is in an intermediate inclination state.

  As shown in FIG. 5C, when the inclination angle of the swash plate 22 is minimum (when the discharge capacity is minimum), the opening 482 of the sleeve 48 is connected to the opening 461 of the first introduction passage 46 and the second introduction passage. 47, the sleeve 48 closes the first introduction passage 46 and the second introduction passage 47. Therefore, the refrigerant in the control pressure chamber 121 flows out from the normally open passage 45 only to the in-shaft passage 44. The passage 41, the accommodation chamber 40, the normally open passage 45, the in-shaft passage 44, the accommodation hole 113, and the throttle hole 143 discharge the refrigerant in the control pressure chamber 121 to the suction pressure region and regulate the pressure in the control pressure chamber 121. A discharge passage is configured.

In the first embodiment, the following effects can be obtained.
(1-1) When the swash plate 22 is in the maximum inclination state, the first introduction passage 46 is opened, and the lubricating oil in the in-shaft passage 44 is first introduced by the centrifugal force accompanying the rotation of the rotary shaft 18. It is possible to flow into the control pressure chamber 121 from the passage 46. That is, when the swash plate 22 is in the maximum inclination state, a sufficient amount of lubricating oil is stored in the control pressure chamber 121. When the swash plate 22 is in the intermediate tilt state, the second introduction passage 47 is opened, and the lubricating oil in the in-shaft passage 44 is removed from the second introduction passage 47 by the centrifugal force accompanying the rotation of the rotating shaft 18. It can flow into the control pressure chamber 121. That is, when the swash plate 22 is in a state other than the minimum inclination state, the lubricating oil in the in-shaft passage 44 is easily returned to the control pressure chamber 121 via the first introduction passage 46 or the second introduction passage 47. The amount of oil stored in the chamber 121 can be increased.

  (1-2) When the swash plate 22 is at an intermediate tilt angle, for example, the first introduction passage 46 is arranged at a position where oil flow from the first introduction passage 46 to the control pressure chamber 121 is blocked by the swash plate 22. It is also assumed that it is installed. In the present embodiment, such a case occurs (configuration in which the opening 461 of the first introduction passage 46 is surrounded by the peripheral wall of the shaft through hole 223 of the swash plate 22). Even in such a case, since the second introduction passage 47 is open, the lubricating oil in the in-shaft passage 44 can flow from the second introduction passage 47 into the control pressure chamber. That is, even when the reduction of the lubricating oil from the first introduction passage 46 is hindered by the swash plate 22, the lubricating oil in the shaft passage 44 passes through the second introduction passage 47 to the control pressure chamber 121. It is easy to be reduced.

  (1-3) The normally open passage 45 becomes a part of a passage for adjusting the pressure in the control pressure chamber 121 by discharging the refrigerant in the control pressure chamber 121 to the suction chamber 131. The shaft seal device 38 is lubricated by the lubricating oil flowing together with the refrigerant passing through the normally open passage 45.

  In the clutchless variable displacement compressor 10, the rotating shaft 18 continues to rotate unless the operation of the vehicle engine E is stopped. Therefore, even when the inclination angle of the swash plate 22 is minimum (a state in which substantial discharge is not performed in the variable capacity compressor 10), sliding contact occurs between the rotary shaft 18 and the shaft seal device 38. That is, it is desirable that the shaft seal device 38 be sufficiently lubricated even when the swash plate 22 is in the minimum inclination state.

  When the inclination angle of the swash plate 22 is the minimum inclination angle, the first introduction passage 46 and the second introduction passage 47 are closed by the sleeve 48. Therefore, the refrigerant in the control pressure chamber 121 flows out from the normally open passage 45 only to the in-shaft passage 44. The configuration that causes such a refrigerant flow from the control pressure chamber 121 to the in-shaft passage 44 is effective in sufficiently lubricating the shaft seal device 38 with the lubricating oil that flows together with the refrigerant that passes through the normally-open passage 45. .

  Further, when the inclination angle of the swash plate 22 is the minimum inclination angle, the refrigerant in the discharge chamber 132 does not flow out to the external refrigerant circuit 28. Therefore, the lubricating oil in the in-shaft passage 44 does not flow out to the external refrigerant circuit 28 via the suction chamber 131 and the discharge chamber 132, and the lubricating oil in the in-shaft passage 44 is reduced to the control pressure chamber 121. The

  (1-4) If the passage cross-sectional area of the first introduction passage 46 is reduced and the passage cross-sectional area of the second introduction passage 47 is increased, the swash plate 22 has an intermediate inclination compared to when the swash plate 22 is in the maximum inclination state. The amount of oil stored in the control pressure chamber 121 during the state can be increased. Conversely, if the passage cross-sectional area of the first introduction passage 46 is increased and the passage cross-sectional area of the second introduction passage 47 is reduced, the swash plate 22 is in the maximum inclined state as compared with the intermediate inclined state. The oil storage amount in the control pressure chamber 121 can be increased.

  That is, by appropriately selecting the size of the cross-sectional area of the first introduction passage 46 and the size of the cross-sectional area of the second introduction passage 47, the oil storage amount in the control pressure chamber 121 is appropriately set according to the inclination angle of the swash plate 22. You can choose.

Next, a second embodiment shown in FIGS. 6A, 6B, and 6C will be described. The same reference numerals are used for the same components as those in the first embodiment.
As shown in FIG. 6A, when the inclination angle of the swash plate 22 is maximum (when the discharge capacity is maximum), the opening 482A of the sleeve 48A is in a position overlapping the opening 471 of the second introduction passage 47. The first introduction passage 46 and the second introduction passage 47 are not closed by the sleeve 48A. Therefore, the lubricating oil in the in-shaft passage 44 can flow into the control pressure chamber 121 from the first introduction passage 46 and the second introduction passage 47 by the centrifugal force accompanying the rotation of the rotating shaft 18.

  As shown in FIG. 6B, in a state where the opening 482A of the sleeve 48A overlaps the opening 471 of the second introduction passage 47, the swash plate 22 has an intermediate inclination angle between the maximum inclination angle and the minimum inclination angle. Is in a state. In the intermediate tilt state, some of the first introduction passages 46 are surrounded by the peripheral wall of the shaft through hole 223 of the swash plate 22. The lubricating oil in the in-shaft passage 44 can flow into the control pressure chamber 121 from the second introduction passage 47 by the centrifugal force accompanying the rotation of the rotating shaft 18. That is, the lubricating oil in the in-shaft passage 44 can flow into the control pressure chamber 121 even when the inclination angle of the swash plate 22 is in an intermediate inclination state.

  As shown in FIG. 6C, when the inclination angle of the swash plate 22 is minimum (when the discharge capacity is minimum), the opening 482A of the sleeve 48A is connected to the opening 461 of the first introduction passage 46 and the second introduction passage. The sleeve 48 </ b> A closes the first introduction passage 46 and the second introduction passage 47. Therefore, the refrigerant in the control pressure chamber 121 flows out from the normally open passage 45 only to the in-shaft passage 44.

  In the present embodiment, when the inclination angle of the swash plate 22 is maximum (when the discharge capacity is maximum), an end surface of the sleeve 48 </ b> A has an annular shape on the end surface of the rotation support 21 so that the end of the sleeve 48 </ b> A does not interfere with the rotation support 21. An escape groove 215 is provided.

  In the second embodiment, the same effect as in the first embodiment can be obtained. In the second embodiment, the second introduction passage 47 is not closed by the sleeve 48A even when the inclination angle of the swash plate 22 is maximum (when the discharge capacity is maximum). Is easy to return to the control pressure chamber 121. Therefore, the oil storage amount in the control pressure chamber 121 when the inclination angle of the swash plate 22 is maximum can be made larger than that in the first embodiment.

In the present invention, the following embodiments are also possible.
(1) As shown in FIG. 7, an annular groove 73 is provided on the peripheral wall surface of the in-shaft passage 44 so as to be continuous with the first introduction passage 46, or the annular groove 74 is provided on the axial passage so as to be continuous with the second introduction passage 47. You may provide in the surrounding wall surface of 44. The annular groove 73 efficiently guides the lubricating oil in the in-shaft passage 44 to the first introduction passage 46, and the annular groove 74 efficiently guides the lubricating oil in the in-shaft passage 44 to the second introduction passage 47. That is, the annular grooves 73 and 74 contribute to making it easier to reduce the lubricating oil to the control pressure chamber 121.

  (2) As shown in FIG. 8, a cylindrical oil separator 75 may be fitted into the in-axis passage 44. The oil separator 75 is provided with a conical guide surface 751 whose diameter is reduced from the first introduction passage 46 side toward the second introduction passage 47 side, and the lubricating oil centrifuged in the in-shaft passage 44 is The guide surface 751 guides the first introduction passage 46. The refrigerant in the in-shaft passage 44 flows out into the suction chamber 131 (see FIG. 1) through the cylinder 752 of the oil separator 75.

The configuration in which the oil separator 75 is provided in the in-shaft passage 44 is effective in effectively separating the lubricating oil from the refrigerant in the in-shaft passage 44 and sending it to the control pressure chamber 121.
(3) An oil separator 76 as shown in FIG. The oil separator 76 includes a radial passage 761, an axial passage 762 communicating with the radial passage 761, and a conical guide surface that decreases in diameter from the first introduction passage 46 side toward the second introduction passage 47 side. 763. The lubricating oil centrifuged in the in-shaft passage 44 is guided to the first introduction passage 46 by the guide surface 763. The refrigerant in the in-shaft passage 44 flows out to the suction chamber 131 (see FIG. 1) through the radial passage 761 and the axial passage 762.

The configuration in which the oil separator 76 is provided in the shaft passage 44 is effective in effectively separating the lubricating oil from the refrigerant in the shaft passage 44 and sending it to the control pressure chamber 121.
(4) An introduction passage different from the first introduction passage 46 and the second introduction passage 47 may be provided in the rotating shaft 18 so that the other introduction passage can be opened and closed by the sleeve 48.

  (5) The present invention is applied to a wobble type variable displacement compressor in which a wobble plate is supported so as to be relatively rotatable by a drive plate as a cam body connected to a rotating support, and the wobble plate and the piston are connected by a connecting rod. May be.

(6) The present invention may be applied to a variable displacement compressor in which a swash plate is tiltably supported by a sleeve.
(7) The present invention may be applied to a variable displacement compressor with a clutch.

1 is a side sectional view showing a first embodiment. AA sectional view taken on the line AA of FIG. FIG. 3 is a sectional view taken along line BB in FIG. 1. The plane sectional view of a hinge mechanism. (A) is a principal part expanded sectional view when the inclination-angle of a swash plate is the largest. (B) is a principal part expanded sectional view when the inclination-angle of a swash plate is intermediate | middle. (C) is a principal part expanded sectional view when the inclination-angle of a swash plate is the minimum. The 2nd Embodiment is shown, (a) is a principal part expanded sectional view when the inclination-angle of a swash plate is the largest. (B) is a principal part expanded sectional view when the inclination-angle of a swash plate is intermediate | middle. (C) is a principal part expanded sectional view when the inclination-angle of a swash plate is the minimum. The principal part expanded sectional view which shows another embodiment. The principal part expanded sectional view which shows another embodiment. The principal part expanded sectional view which shows another embodiment.

Explanation of symbols

  10: Variable capacity compressor. 121: Control pressure chamber. 131: A suction chamber as a suction pressure region. 143: A throttle hole that becomes a part of the discharge passage. 18 ... Rotating shaft. 22 ... A swash plate as a cam body. 24 ... Piston. 28, 28A, 28B ... External refrigerant circuit. 38 ... Shaft seal device. 40: Containment room. 44: An in-axis passage that becomes a part of the discharge passage. 45: A normally open passage that becomes a part of the discharge passage. 46: First introduction passage. 47. Second introduction passage. 48, 48A ... Sleeve as a moving body. 51: Supply passage. E: Vehicle engine as an external drive source.

Claims (7)

The piston is interlocked with the rotation of the rotation shaft through a cam body that rotates integrally with the rotation shaft, and the refrigerant in the discharge pressure region is supplied to the control pressure chamber that accommodates the cam body in a variable tilt angle via the supply passage. At the same time, the refrigerant in the control pressure chamber is discharged to the suction pressure region through the discharge passage to adjust the pressure in the control pressure chamber, and the tilt angle of the cam body is changed by the pressure adjustment in the control pressure chamber. In the variable capacity compressor whose discharge capacity is controlled by
As a part of the discharge passage, an in-axis passage provided in the rotation shaft so as to extend in the axial direction of the rotation shaft;
A first introduction passage for communicating the control pressure chamber and the in-shaft passage;
A second introduction passage for communicating the control pressure chamber and the in-shaft passage;
A movable body that moves in the axial direction of the rotation shaft in conjunction with the tilting of the cam body and that can open and close the first introduction passage and the second introduction passage;
The variable capacity compressor, wherein the first introduction passage and the second introduction passage are provided at positions separated from each other in the axial direction of the rotating shaft.   The movable body can open both the first introduction passage and the second introduction passage at the same time, and the movable body opens both the first introduction passage and the second introduction passage at the same time. 2. The variable capacity compressor according to claim 1, wherein the cam body has an intermediate inclination angle.   3. The variable capacitance according to claim 1, wherein when the cam body has a maximum inclination angle, the first introduction passage is opened and the second introduction passage is closed. 4. Mold compressor.   4. The variable capacity compressor according to claim 1, wherein both the first introduction passage and the second introduction passage are opened when the inclination angle of the cam body is a maximum inclination angle. 5. .   A shaft seal device for preventing refrigerant leakage from the control pressure chamber along the peripheral surface of the rotary shaft is provided, and a normally open passage is provided in the rotary shaft with a housing chamber for housing the shaft seal device and in the shaft. When the first introduction passage and the second introduction passage are closed, the refrigerant in the control pressure chamber passes through the normally-open passage and passes through the in-shaft passage. The variable capacity compressor according to any one of claims 1 to 4, wherein the compressor is discharged into the compressor.   The variable displacement compressor according to claim 5, wherein when the cam body has a minimum inclination angle, the first introduction passage and the second introduction passage are closed by the movable body.   7. The variable capacity compressor according to claim 1, wherein the variable capacity compressor is a clutchless variable capacity compressor capable of obtaining a rotational driving force from an external drive source without a clutch and capable of stopping refrigerant circulation in an external refrigerant circuit. The variable capacity compressor according to claim 1.

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