JP2017150315A - Variable displacement swash plate compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable displacement swash plate compressor capable of actualizing quicker discharge of liquid refrigerant at start than conventional one, while enabling a proper amount of lubricating oil to be held during high rotation.SOLUTION: A check valve 84 has a valve storage chamber 85 provided in a housing, and a check valve element 86 stored in the valve storage chamber 85 and including a through-hole for refrigerant supplied from a first control valve to pass therethrough and a valve part for restricting the backflow of refrigerant gas into the first control valve, the housing including a communication passage 90 communicating the valve storage chamber 85 and an extraction passage, a first passage 87 communicating the valve storage chamber 85 and a control pressure chamber, and a second passage 88 communicating the valve storage chamber 85 and the first control valve. The check valve element 86 opens the communication passage 90 when a pressure in the first passage 87 is higher than a pressure in the second passage 88, and closes the communication passage 90 when the pressure in the first passage 87 is lower than the pressure in the second passage 88.SELECTED DRAWING: Figure 2

Description

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

  As a conventional technique of the variable capacity swash plate compressor, for example, a capacity control mechanism in the variable capacity compressor disclosed in Patent Document 1 can be cited. In the variable displacement compressor disclosed in Patent Document 1, the refrigerant in the discharge pressure region is supplied to the control pressure chamber via the supply passage, and the refrigerant in the control pressure chamber is discharged to the suction pressure region via the discharge passage. Thus, the pressure in the control pressure chamber is adjusted, and the discharge capacity is controlled by the pressure adjustment in the control pressure chamber. The supply passage is provided with a first control valve for adjusting the passage sectional area.

  The variable displacement compressor disclosed in Patent Document 1 includes a second control valve. The second control valve has a valve hole that opens to the control pressure chamber and connects to the valve storage chamber, and a first valve portion that adjusts the passage cross-sectional area of the valve hole. Further, the valve storage chamber is partitioned into a discharge chamber that is a part of the discharge passage and a back pressure chamber that communicates with the supply passage, and a flow passage that communicates between the discharge chamber and the back pressure chamber is formed inside the valve storage chamber. The 2nd valve part left between peripheral surfaces is provided. The second control valve has a valve seat forming portion that contacts and separates from the end surface on the discharge chamber side of the second valve portion, but the valve seat forming portion is separate from the casing that forms the valve accommodating chamber.

  In the variable displacement compressor disclosed in Patent Document 1, when the first control valve shifts from the valve open state to the valve closed state, the second control valve starts to shift from the valve closed state to the open state. At this time, since the residual pressure in the back pressure chamber is released to the discharge chamber side through the flow passage, the responsiveness of the second control valve is good. Since the flow passage can be enlarged (the clearance between the outer peripheral surface of the second valve portion and the inner peripheral surface of the valve storage chamber can be increased), the outer peripheral surface of the second valve portion and the inner peripheral surface of the valve storage chamber Even if a foreign object enters between the two, the second control valve is not likely to be inhibited from moving by the foreign object. Therefore, even if foreign matter enters between the outer peripheral surface of the second valve portion and the inner peripheral surface of the valve storage chamber, the discharge capacity can be quickly increased immediately after the start of the variable displacement compressor.

JP 2011-185138 A

  In the variable capacity compressor disclosed in Patent Document 1, when starting from a state in which liquid refrigerant is stored in the control pressure chamber, the liquid refrigerant is discharged from the control pressure chamber to the suction pressure region and then the control pressure chamber. Pressure regulation is performed. Therefore, in order to quickly increase the discharge capacity immediately after starting the variable capacity compressor, it is necessary to quickly discharge the liquid refrigerant from the control pressure chamber. Incidentally, it is also conceivable to provide a hole in the housing for discharging the liquid refrigerant in the control pressure chamber. However, when the hole is provided in the housing, there are problems that the lubricating oil is discharged together with the liquid refrigerant from the control pressure chamber, leading to a shortage of the lubricating oil and impairing the circulation of the lubricating oil inside the compressor. In particular, the lack of lubricating oil at high rotations leads to a reduction in the reliability of the compressor.

  The present invention has been made in view of the above problems, and an object of the present invention is to discharge liquid refrigerant more quickly than before at the time of start-up and to maintain an appropriate amount of lubricating oil at high rotation. To provide a variable displacement swash plate compressor.

  In order to solve the above-described problems, the present invention provides a housing having a suction chamber, a discharge chamber, a control pressure chamber, and a plurality of cylinder bores, a drive shaft rotatably supported by the housing, and the control pressure chamber. The swash plate that rotates integrally with the drive shaft and can be tilted with respect to the drive shaft, and is slidably received in the cylinder bore, and reciprocates in the cylinder bore by receiving the rotational movement of the swash plate. A piston that moves, an air supply passage through which refrigerant in the discharge pressure region passes through the control pressure chamber, a first control valve that adjusts a cross-sectional area of the air supply passage, and the refrigerant in the control pressure chamber passes through the suction pressure region A bleed passage, a second control valve that adjusts a passage cross-sectional area of the bleed passage, and a check valve provided between the control pressure chamber and the first control valve in the supply passage, The piston is adjusted by adjusting the pressure in the control pressure chamber. In the variable displacement swash plate compressor in which the stroke is adjusted, the check valve is housed in a valve housing chamber provided in the housing, and a through hole for passing a refrigerant supplied from the first control valve and a refrigerant gas A non-return valve body having a valve portion for restricting back flow to the first control valve, wherein the housing communicates with the valve housing chamber and the extraction passage, the valve housing chamber and the control pressure; A first passage communicating with the chamber and a second passage communicating between the valve housing chamber and the first control valve, wherein the check valve body is configured such that the pressure in the first passage is the second passage. The communication passage is opened when the pressure in the first passage is higher, and the communication passage is closed when the pressure in the first passage is lower than the pressure in the second passage.

  In the present invention, the check valve body of the check valve opens the communication passage when the pressure in the first passage is higher than the pressure in the second passage, and the pressure in the first passage is the pressure in the second passage. If it is lower, close the communication passage. For example, even when the liquid refrigerant is stored in the control pressure chamber at the time of startup, the liquid refrigerant is discharged to the suction pressure region through a part of the air supply passage, the communication passage, and the extraction passage by opening the communication passage. Is done. As a result, the liquid refrigerant can be discharged more quickly than when the liquid refrigerant is discharged only through the extraction passage at the time of activation. That is, by providing the communication passage, the liquid refrigerant stored in the control pressure chamber at the time of activation can be quickly discharged to the suction pressure region. Further, since the refrigerant supplied from the first control valve passes through the check valve body at the time of high rotation, the check valve body closes the communication passage. By closing the communication passage, the lubricating oil is not discharged from the control pressure chamber through the communication passage.

In the variable displacement swash plate compressor, the cross-sectional area of the communication passage may be larger than the cross-sectional area of the first passage.
In this case, the passage cross-sectional area of the communication passage is larger than the passage cross-sectional area of the first passage. Therefore, when the liquid refrigerant is discharged to the suction pressure region through the first passage, the communication passage, and the extraction passage, the communication passage is throttled. The liquid refrigerant can be passed smoothly without being received.

  According to the present invention, it is possible to provide a variable capacity swash plate compressor capable of discharging liquid refrigerant more quickly than before at the time of startup and capable of maintaining an appropriate amount of lubricating oil during high rotation. .

1 is a longitudinal sectional view of a variable capacity swash plate compressor according to an embodiment of the present invention. It is a longitudinal section of the important section of the variable capacity type swash plate type compressor concerning the embodiment of the present invention. It is principal part sectional drawing explaining opening and closing of the 2nd control valve of a variable capacity type | mold swash plate type compressor. It is principal part sectional drawing explaining opening and closing of the non-return valve of a variable capacity | capacitance type swash plate type compressor.

(First embodiment)
Hereinafter, a variable displacement swash plate compressor according to a first embodiment will be described with reference to the drawings. A variable capacity swash plate compressor (hereinafter referred to as “compressor”) according to the present embodiment is a compressor for vehicle air conditioning mounted on a vehicle.

  In the compressor shown in FIG. 1, a front housing 12 is joined to the front end of the cylinder block 11, and a rear housing 13 is joined to the rear end of the cylinder block 11. The cylinder block 11, the front housing 12, and the rear housing 13 are connected to each other by a plurality of through bolts 14 (only one is shown in FIG. 1). The cylinder block 11, the front housing 12, and the rear housing 13 are elements constituting the compressor housing, and are formed of an aluminum-based metal material.

  A control pressure chamber 15 is formed between the front housing 12 and the cylinder block by joining the front housing 12 and the cylinder block 11. A shaft hole 16 is formed in the cylinder block 11. A drive shaft 17 is inserted into the shaft hole 16, and the drive shaft 17 is rotatably supported by the cylinder block 11 via a slide bearing 18. A shaft hole 19 is formed in the front housing 12, and a drive shaft 17 is inserted through the shaft hole 19. The drive shaft 17 is rotatably supported by the front housing 12 via a slide bearing 20. A shaft sealing device 22 is provided in front of the shaft hole 19. The shaft seal device 22 is disposed between the front housing 12 and the drive shaft 17. A shaft sealing chamber 21 is defined by the front housing 12, the drive shaft 17 and the shaft sealing device 22.

  The shaft seal device 22 has a function of sealing between the drive shaft 17 and the front housing 12 and preventing leakage of refrigerant gas from the control pressure chamber 15 through the shaft hole 19 and the shaft seal chamber 21. The device 22 uses a lip seal formed mainly of a rubber material. The drive shaft 17 slides relative to the shaft seal device 22 during rotation. The drive shaft 17 that protrudes outside from the control pressure chamber 15 obtains a rotational drive force from an external drive source (not shown) such as an engine. The compressor of this embodiment is a clutchless compressor that is driven following the driving of an external drive source. A rotary support 23 is fixed to the drive shaft 17. The rotary support 23 rotates integrally with the drive shaft 17. A thrust bearing 24 is interposed between the rotary support 23 and the inner wall surface of the front housing 12. The thrust bearing 24 receives a load acting in the thrust direction (direction of the drive shaft center P of the drive shaft 17). A swash plate 25 is supported on the rotary support 23 so as to be slidable and tiltable in the direction of the drive axis P.

  The front housing 12 is formed with a lubricating oil passage 26 extending from the outer peripheral region of the control pressure chamber 15 to between the front housing 12 and the rotary support 23 and facing the thrust bearing 24. The lubricating oil passage 26 is provided on the inner wall surface of the front housing 12 from the outer circumferential area of the control pressure chamber 15 toward the inner circumferential area, and from the end on the inner circumferential area side of the groove 26A to the shaft sealing chamber 21. A through-hole 26B penetrating toward is provided. The inner peripheral region of the control pressure chamber 15 refers to a region close to the drive shaft 17 in the control pressure chamber 15, and the outer peripheral region of the control pressure chamber 15 refers to the drive shaft in the radial direction of the drive shaft 17 in the control pressure chamber 15. The area | region which is distant from the radial direction of the drive shaft 17 with respect to the 17 inner peripheral area is pointed out.

  A pair of arms 28 project from the rotation support 23 toward the swash plate 25, and a pair of protrusions 29 project from the swash plate 25 toward the rotation support 23. In FIG. 1, only one arm 28 and one protrusion 29 are shown, and the other arm 28 and the other protrusion 29 are not shown. The protrusion 29 is inserted into a recess formed between the pair of arms 28 in the rotary support 23. The protrusion 29 can move in the recess while being sandwiched between the pair of arms 28. A cam surface 30 is formed on the surface of the arm 28 which becomes the bottom of the recess, and the tip of the protrusion 29 is in sliding contact with the cam surface 30. The swash plate 25 can be tilted in the axial direction of the drive shaft 17 and can rotate integrally with the drive shaft 17 by linking the projection 29 sandwiched between the pair of arms 28 and the cam surface 30.

  The tilting of the swash plate 25 is guided by the slide guide relationship between the cam surface 30 and the projection 29 and the slide support action of the drive shaft 17. The pair of arms 28, the projecting portion 29, and the cam surface 30 constitute a hinge mechanism 31 provided between the swash plate 25 and the rotary support 23. The hinge mechanism 31 connects the swash plate 25 with respect to the rotary support 23 so that the swash plate 25 can tilt and transmit torque from the drive shaft 17 to the swash plate 25.

  A coil spring 32 is inserted into the drive shaft 17, and the coil spring 32 is located between the rotary support 23 and the swash plate 25. The coil spring 32 applies an urging force that separates the swash plate 25 from the rotary support 23 to the swash plate 25. When the diameter center portion of the swash plate 25 moves toward the rotary support 23, the inclination angle of the swash plate 25 with respect to the radial direction of the drive shaft 17 increases. The maximum inclination angle of the swash plate 25 is defined by the contact between the rotary support 23 and the swash plate 25. Incidentally, the swash plate 25 shown by the solid line in FIG. 1 is in the state of the maximum inclination angle, and the swash plate 25 shown by the two-dot chain line is in the state of the minimum inclination angle.

  As shown in FIG. 1, a single-headed piston 34 is slidably accommodated in a plurality of cylinder bores 33 formed in the cylinder block 11. A compression chamber 35 is defined by the cylinder bore 33 and the end face of the piston 34. The rotational movement of the swash plate 25 is converted into the back-and-forth reciprocating movement of the piston 34 via the shoe 36, and the piston 34 reciprocates in the cylinder bore 33.

  A partition wall 37 is formed in the rear housing 13, and a suction chamber 38 and a discharge chamber 39 are defined by the partition wall 37 in the rear housing 13. A valve plate 40 and valve forming plates 41 and 42 are interposed between the cylinder block 11 and the rear housing 13. A suction port 43 is formed in the valve plate 40 and the valve forming plate 42. A discharge port 44 is formed in the valve plate 40 and the valve forming plate 41. A suction valve 45 is formed on the valve forming plate 41, and a discharge valve 46 is formed on the valve forming plate 42. A through hole 47 is provided on the extension line of the drive shaft center P in the valve plate 40 and the valve forming plates 41 and 42 so as to connect the shaft hole 16 and the discharge chamber 39. Bolts 48 are inserted into the through holes 47, and the retainer forming plate 49 is fastened by the bolts 48 and the nuts 50. The retainer forming plate 49 is formed with a retainer 51 that regulates the opening degree of the discharge valve 46.

  The refrigerant in the suction chamber 38 opens the suction valve 45 from the suction port 43 and flows into the cylinder bore 33 by the suction operation of the piston 34 (movement from the right side to the left side in FIG. 1). The gaseous refrigerant that has flowed into the cylinder bore 33 is discharged from the discharge port 44 to the discharge chamber 39 by opening the discharge valve 46 by the discharge operation of the piston 34 (movement from the left side to the right side in FIG. 1). The discharge valve 46 is brought into contact with the retainer 51 on the retainer forming plate 49 and the opening thereof is regulated.

  The suction passage 52 for introducing the refrigerant into the suction chamber 38 and the discharge passage 53 for discharging the refrigerant from the discharge chamber 39 are connected to the external refrigerant circuit 54. On the external refrigerant circuit 54, a condenser 55 for liquefying the refrigerant, an expansion valve 56, and a heat exchanger 57 for transferring ambient heat to the refrigerant are interposed. The expansion valve 56 controls the flow rate of the refrigerant according to the change in the temperature of the refrigerant gas on the outlet side of the heat exchanger 57.

  The refrigerant gas discharged to the discharge chamber 39 passes through the discharge passage 53 and is discharged to the external refrigerant circuit 54. The refrigerant gas discharged to the external refrigerant circuit 54 returns to the suction chamber 38 through the suction passage 52. The discharge chamber 39 and the control pressure chamber 15 communicate with each other through an air supply passage 58. The rear housing 13 is provided with a capacity control valve 59, and the capacity control valve 59 controls the flow rate of the refrigerant gas passing through the air supply passage 58. The capacity control valve 59 includes a suction port 60 through which a refrigerant gas having a discharge pressure is sucked, a discharge port 61 through which the regulated refrigerant gas is discharged, and a solenoid (not shown). The capacity control valve 59 corresponds to a first control valve that adjusts the passage cross-sectional area of the air supply passage 58.

  When the flow rate of the refrigerant gas passing through the supply passage 58 increases due to the increase in the valve opening degree of the capacity control valve 59, the pressure in the control pressure chamber 15 increases. Thereby, the inclination angle of the swash plate 25 decreases. When the flow rate of the refrigerant gas passing through the air supply passage 58 decreases due to the decrease in the valve opening degree of the capacity control valve 59, the pressure in the control pressure chamber 15 decreases. Thereby, the inclination angle of the swash plate 25 increases. The stroke of the piston 34 is changed and adjusted by increasing or decreasing the inclination angle of the swash plate 25.

  In the drive shaft 17 of the present embodiment, an in-shaft passage 62 formed in the axial direction around the drive shaft center P is formed. The in-shaft passage 62 provided in the drive shaft 17 is formed from one end on the rear housing 13 side toward the other end on the front housing 12 side. The end of the in-shaft passage 62 that is the other end on the front housing 12 side reaches between the shaft seal device 22 and the slide bearing 20 in the axial direction of the drive shaft 17. As shown in FIG. 1, a hole 63 extending from the end of the in-shaft passage 62 on the front housing 12 side to the outer periphery of the drive shaft 17 in the radial direction is formed.

  A space 64 is formed on the valve plate 40 side of the shaft hole 16 in the cylinder block 11. As shown in FIG. 2, the space 64 is partitioned by the cylinder block 11 and the valve plate 40. The space 64 and the suction chamber 38 are communicated with each other by a housing passage 65 provided in the cylinder block 11. Therefore, the control pressure chamber 15 and the suction chamber 38 communicate with each other through the lubricating oil passage 26, the hole 63, the in-shaft passage 62, the space 64, and the housing passage 65.

  As shown in FIG. 1, in this embodiment, a small-diameter shaft portion 66 having a small outer peripheral diameter is formed at the end of the drive shaft 17 on the cylinder block 11 side. A cylindrical member 67 accommodated in the space portion 64 is attached to the small diameter shaft portion 66 of the drive shaft 17. The tubular member 67 has a funnel shape whose diameter increases from the drive shaft 17 toward the valve plate 40, and includes a plurality of through holes (not shown). A slight gap is formed between the end of the tubular member 67 on the valve plate 40 side and the valve forming plate 41. Normally, the end of the tubular member 67 on the valve plate 40 side and the valve forming plate 41 are in contact with each other. Does not touch.

  In the present embodiment, a second control valve 68 that adjusts the passage sectional area of the housing passage 65 is provided. A valve accommodating chamber 69 is provided in the housing passage 65. The valve storage chamber 69 is recessed in the cylinder block 11 facing the valve forming plate 41. The valve storage chamber 69 includes a small-diameter chamber 70 that is a part of the housing passage 65 and a large-diameter chamber 71 that is larger in diameter than the small-diameter chamber 70. An annular valve seat forming ring 72 is fitted in the large diameter chamber 71. The outer diameter of the valve seat forming ring 72 is slightly smaller than the inner diameter of the large-diameter chamber 71. A valve element 73 is accommodated in the valve accommodating chamber 69 so as to penetrate the hole of the valve seat forming ring 72. The valve body 73 passes through the ring of the valve seat forming ring 72 and extends to the small diameter chamber 70, and is accommodated in the large diameter chamber 71, and is connected to the small diameter valve portion 74 via the connecting portion 75. A large-diameter valve portion 76 is connected. The connecting portion 75 is inserted through the through hole of the small diameter valve portion 74, and the connecting portion 75 and the small diameter valve portion 74 are fixed to each other.

  The large diameter valve portion 76 defines a back pressure chamber 77 in the large diameter chamber 71. The small diameter valve portion 74 defines a throttle chamber 78 in the small diameter chamber 70. The housing passage 65 includes a first connection passage 79 that connects the space portion 64 and the throttle chamber 78, and a second connection passage 80 that connects the throttle chamber 78 and the suction chamber 38. Accordingly, the housing passage 65 includes the first connection passage 79, the throttle chamber 78, and the second connection passage 80. The throttle chamber 78 is provided with a valve hole 81 that opens to the first connection passage 79, and the small-diameter valve portion 74 adjusts the opening degree of the valve hole 81. A protrusion 74 </ b> A is provided on the end surface of the valve hole 81 of the small diameter valve portion 74. By providing the protrusion 74A, the small diameter valve portion 74 does not completely close the valve hole 81. The second connection passage 80 communicates with the suction chamber 38 which is a suction pressure region through the cylinder block 11, the valve plate 40, the valve forming plates 41 and 42, the retainer forming plate 49 and the rear housing 13. The back pressure chamber 77 communicates with the air supply passage 58 through the valve plate 40, the valve forming plates 41 and 42, the retainer forming plate 49, and the pressure guide passage 82 that passes through the rear housing 13. In the present embodiment, the lubricating oil passage 26, the hole 63, the in-shaft passage 62, the space portion 64, and the housing passage 65 constitute an extraction passage.

  The second control valve 68 changes the opening degree of the valve hole 81 by the pressure difference between the back pressure chamber 77 and the throttle chamber 78. For example, when starting the compressor in a state where liquid refrigerant is stored, the opening degree of the valve hole 81 is maximized so that the liquid refrigerant in the control pressure chamber 15 is easily discharged to the suction chamber 38. Further, when the capacity control valve 59 supplies the refrigerant to the control pressure chamber 15 during the minimum capacity operation or the variable capacity operation, the second control valve 68 reduces the opening of the valve hole 81 to the minimum or small. Leakage from the gas control pressure chamber 15 to the suction chamber 38 is minimized.

  Incidentally, in the present embodiment, a check valve 84 is provided in the air supply passage 58. A valve housing chamber 85 is recessed in the end surface of the cylinder block 11 facing the valve forming plate 41. The check valve 84 includes a check valve body 86 housed in the valve housing chamber 85. The supply passage 58 includes a first passage 87 that communicates the control pressure chamber 15 and the valve storage chamber 85, a second passage 88 that communicates the discharge port 61 of the capacity control valve 59 and the valve storage chamber 85, and a discharge pressure. And a third passage 89 that communicates the discharge chamber 39 as a region and the suction port 60 of the capacity control valve 59.

  The hole diameter of the valve accommodating chamber 85 is larger than the inner diameter of the first passage 87. The cylinder block 11 is provided with a communication passage 90 that communicates with the space 64 from the first passage 87 of the valve storage chamber 85. The hole diameter of the communication passage 90 is larger than the inner diameter of the first passage 87. The first passage 87 and the communication passage 90 are located below the extraction passage when the compressor is installed in the vehicle.

  The check valve body 86 reciprocates in the valve accommodating chamber 85 in a direction parallel to the drive axis P direction. The check valve body 86 includes a cylindrical large-diameter valve portion 91 having an outer diameter slightly smaller than the hole diameter of the valve housing chamber 85, and a cylindrical small-diameter valve portion 92 having an outer diameter smaller than that of the large-diameter valve portion 91. ing. The end surface of the large-diameter valve portion 91 is opened, and the end surface of the small-diameter valve portion 92 is bottomed and closed. The small diameter valve portion 92 is provided with a plurality of through holes 93 penetrating from the outer peripheral surface to the inner peripheral surface. The bottom portion of the small diameter valve portion 92 opens and closes the second passage 88 by the movement of the check valve body 86. Therefore, the small-diameter valve portion 92 has a function of preventing the refrigerant from flowing backward from the control pressure chamber 15 to the capacity control valve 59. The large-diameter valve portion 91 opens and closes the communication passage 90 by the movement of the check valve body 86. The check valve body 86 is preferably formed of a material having a thermal expansion coefficient close to that of the aluminum-based metal material that is the material of the cylinder block 11.

  The check valve body 86 opens the communication passage 90 when the pressure in the first passage 87 is higher than the pressure in the second passage 88, and the pressure in the first passage 87 is higher than the pressure in the second passage 88. When it is low, the communication passage 90 is closed. For example, the check valve 84 closes the second passage 88 so that the refrigerant gas in the control pressure chamber 15 does not leak to the second control valve 68 at the time of starting the compressor, and at the time of minimum capacity operation or variable capacity operation. When the capacity control valve 59 supplies the refrigerant to the control pressure chamber 15, the second passage 88 is opened. The check valve 84 communicates so that the liquid refrigerant in the control pressure chamber 15 is discharged to the suction chamber 38 through the space 64 when the compressor is started in a state where the liquid refrigerant is stored in the control pressure chamber 15. Open passage 90.

  Next, the operation of the compressor of this embodiment will be described. When the compressor is operated, the refrigerant gas is introduced from the external refrigerant circuit 54 into the suction chamber 38 through the suction passage 52. In the suction stroke in which the piston 34 reciprocating in the cylinder bore 33 moves from the top dead center position to the bottom dead center position, the suction valve 45 is opened. At this time, the refrigerant gas in the suction chamber 38 flows into the suction valve 45. It is introduced into the compression chamber 35 through the suction port 43 when the valve is opened. In the intake stroke, the discharge valve 46 closes the valve plate 40 and closes the discharge port 44 without being bent, coupled with a decrease in pressure in the compression chamber 35 and a high pressure in the discharge chamber 39. Thereafter, in the compression stroke in which the piston 34 moves from the bottom dead center position to the top dead center position, the pressure in the compression chamber 35 increases and the refrigerant gas in the compression chamber 35 is compressed.

  In the compression stroke, the pressure in the compression chamber 35 increases. In the discharge stroke, the discharge valve 46 is curved to open the discharge port 44, and the refrigerant gas in the compression chamber 35 is discharged to the discharge chamber 39 through the discharge port 44. At the same time, coupled with the pressure increase in the compression chamber 35 and the low pressure in the suction chamber 38, the suction valve 45 comes into close contact with the valve plate 40 and closes the suction port 43. When the piston 34 reaches the top dead center position, the refrigerant gas is discharged from the compression chamber 35 to the discharge chamber 39 and the discharge of the refrigerant gas ends, the discharge valve 46 moves away from the retainer 51 and closes the discharge port 44. Then, the refrigerant gas discharged from the compression chamber 35 to the discharge chamber 39 is led to the external refrigerant circuit 54 through the discharge passage 53. The refrigerant gas flowing out to the external refrigerant circuit 54 returns to the suction chamber 38 through the suction passage 52.

  The pressure in the control pressure chamber 15 is adjusted according to the valve opening of the capacity control valve 59, and when the flow rate of the refrigerant gas passing through the supply passage 58 increases due to the increase in the valve opening of the capacity control valve 59, the control pressure is increased. The pressure in the chamber 15 increases. As the pressure in the control pressure chamber 15 increases, the inclination angle of the swash plate 25 decreases. When the flow rate of the refrigerant gas passing through the supply passage 58 decreases due to the decrease in the opening degree of the discharge port 61 of the capacity control valve 59, the pressure in the control pressure chamber 15 decreases. As the pressure in the control pressure chamber 15 decreases, the inclination angle of the swash plate 25 increases. The stroke of the piston 34 is adjusted by adjusting the pressure in the control pressure chamber 15.

  During the minimum capacity operation, the opening degree of the discharge port 61 of the capacity control valve 59 is maximized, and the amount of refrigerant gas from the capacity control valve 59 to the supply passage 58 increases. Therefore, the second passage 88 of the air supply passage 58 becomes higher than the pressure of the control pressure chamber 15, and the check valve body 86 of the check valve 84 moves toward the control pressure chamber 15 side to move to the second passage 88. The communication passage 90 is closed by a check valve body 86 (see FIG. 4A). The refrigerant gas in the control pressure chamber 15 is sucked through the lubricating oil passage 26, the in-shaft passage 62 of the drive shaft 17, the hole 63, the space portion 64, the first connection passage 79, and the second connection passage 80. It is discharged into the chamber 38. During the minimum capacity operation, in the second control valve 68, the pressure in the back pressure chamber 77 is higher than the pressure in the throttle chamber 78, and the valve body 73 minimizes the opening degree of the valve hole 81 of the second control valve 68 ( (See FIG. 3 (a)). For this reason, it is difficult for the refrigerant gas in the control pressure chamber 15 to be discharged to the suction chamber 38.

  On the other hand, during the maximum capacity operation, the discharge port 61 of the capacity control valve 59 is closed, and the refrigerant gas is not supplied from the capacity control valve 59 to the air supply passage 58. For this reason, the second passage 88 of the air supply passage 58 becomes lower than the pressure of the control pressure chamber 15, and the check valve body 86 of the check valve 84 moves toward the valve forming plate 41 to move to the second passage 88. Is closed and the communication passage 90 is opened (see FIG. 4B). During the maximum capacity operation, the pressure in the back pressure chamber 77 in the second control valve 68 is lower than the pressure in the throttle chamber 78, and the valve element 73 maximizes the opening degree of the valve hole 81 of the second control valve 68 (see FIG. 3 (b)). For this reason, the refrigerant gas in the control pressure chamber 15 is easily discharged to the suction chamber 38. The refrigerant gas in the control pressure chamber 15 is sucked through the lubricating oil passage 26, the in-shaft passage 62 of the drive shaft 17, the hole 63, the space portion 64, the first connection passage 79, and the second connection passage 80. It is discharged into the chamber 38. On the other hand, the refrigerant gas in the control pressure chamber 15 is discharged to the suction chamber 38 through the first passage 87, the communication passage 90, the first connection passage 79, and the second connection passage 80.

  By the way, in a compressor of a general vehicle air conditioner, when a liquid refrigerant (hereinafter referred to as “liquid refrigerant”) exists on the low pressure side of the external refrigerant circuit 54 with the engine stopped for a long time, the liquid refrigerant is It flows into the control pressure chamber 15 through the suction chamber 38. In particular, when the temperature on the vehicle interior side is high and the temperature on the engine room side where the compressor is disposed is low, a large amount of liquid refrigerant flows into the control pressure chamber 15 via the suction chamber 38 and stays there. The

  For this reason, when driving of the compressor is started, the liquid refrigerant is vaporized by the influence of heat generation of the engine and stirring by the swash plate 25, and the pressure of the control pressure chamber becomes the valve opening degree of the capacity control valve 59. Regardless, it rises. At the same time, the inclination angle of the swash plate 25 is slightly larger than 0 °, and the refrigerant is discharged from the cylinder bore 33 into the discharge chamber 39 even when the inclination angle of the swash plate 25 is the smallest. At this time, in the second control valve 68, since the pressure in the throttle chamber 78 is higher than the pressure in the back pressure chamber 77, the valve body 73 increases the opening degree of the valve hole 81 as shown in FIG. Move to the annuloplasty plate 41 side to maximize.

  Even if the pressure in the control pressure chamber 15 becomes larger than the pressure in the discharge chamber 39, the check valve 84 prevents the pressure in the control pressure chamber 15 from acting on the air supply passage 58. Specifically, the check valve body 86 of the check valve 84 moves to the valve forming plate 41 and blocks the air supply passage 58. Therefore, the pressure of the control pressure chamber 15 is prevented from acting on the back pressure chamber 77 of the second control valve 68 via the air supply passage 58 and the pressure guide passage 82, and the pressure of the back pressure chamber 77 increases. There is nothing. For this reason, the valve body 73 of the second control valve 68 maintains a state where the extraction passage is fully opened based on the pressure difference between the throttle chamber 78 and the back pressure chamber 77.

  In the state where the check valve body 86 of the check valve 84 moves to the valve forming plate 41 and shuts off the air supply passage 58 as shown in FIG. And the communication passage 90 communicate with each other. That is, a part of the supply passage 58 and the extraction passage are in communication with each other. Accordingly, the liquid refrigerant in the control pressure chamber 15 is in a liquid state or in a state where at least a part thereof is vaporized, so that the first passage 87 of the air supply passage 58, the communication passage 90, the space portion 64, the first connection passage 79, the second passage. It is quickly discharged into the suction chamber 38 via the connection passage 80. In FIG.4 (b), the flow of refrigerant gas is shown by the arrow. Note that the liquid refrigerant in the control pressure chamber 15 remains in a liquid state or is at least partially vaporized, and the lubricating oil passage 26, the shaft passage 62, the hole 63, the space portion 64, and the first connection. The air is discharged to the suction chamber 38 through the passage 79 and the second connection passage 80. That is, the liquid refrigerant is discharged from the extraction passage.

  In the present embodiment, the supply passage 58 in a state where the compressor is installed in the vehicle is located below the extraction passage. Further, the route to the first passage 87, the communication passage 90, the space 64, the first connection passage 79, the second control valve 68, the second connection passage 80, and the suction chamber 38 is compared with the length of the extraction passage. short. For this reason, the liquid refrigerant is sucked through the first passage 87, the communication passage 90, the space 64, the first connection passage 79, and the second connection passage 80, rather than discharging the liquid refrigerant into the suction chamber 38 through the extraction passage. The discharge to the chamber 38 takes a shorter time. When the liquid refrigerant is discharged from the control pressure chamber 15 and the pressure in the control pressure chamber 15 decreases, the inclination angle of the swash plate 25 increases as the pressure in the control pressure chamber 15 decreases.

  By the way, the compressor of this embodiment is a clutchless type compressor driven following the drive of an external drive source. For this reason, when the external drive source is operated at a high speed, the rotational speed of the compressor follows the high speed. When the compressor is driven at a high speed, the load on the compressor is large, and a sufficient amount of lubricating oil is necessary to lubricate the sliding portion of the compressor. Therefore, in the compressor of the present embodiment, when the compressor operating at the maximum capacity becomes a high speed exceeding the preset rotation speed, a little refrigerant is supplied to the capacity control valve 59 in order to protect the compressor. The control to supply to the control pressure chamber 15 is performed. For this reason, the inclination angle of the swash plate 25 becomes slightly smaller than that during the maximum capacity operation, and the load on the compressor is reduced.

  During high rotation, the refrigerant gas is slightly supplied from the capacity control valve 59 to the control pressure chamber 15, so that the pressure in the back pressure chamber 77 in the second control valve 68 becomes higher than the pressure in the throttle chamber 78. Due to the differential pressure between the throttle chamber 78 and the back pressure chamber 77, the valve body 73 is moved toward the control pressure chamber 15 so as to reduce the opening of the valve hole 81, as shown in FIG. . Accordingly, the opening degree of the extraction passage is minimized.

  At the time of high rotation, in the check valve 84, the check valve body 86 is moved to the control pressure chamber 15 side by the pressure of the refrigerant gas from the capacity control valve 59 as shown in FIG. The air supply passage 58 is opened by the movement of the check valve body 86, and the refrigerant gas from the capacity control valve 59 is supplied to the control pressure chamber 15 through the air supply passage 58. In FIG. 4A, the flow of the refrigerant gas is indicated by arrows. Further, the check valve body 86 blocks the first passage 87 and the communication passage 90 by moving the check valve body 86 toward the control pressure chamber 15. That is, the extraction passage and the supply passage 58 are not communicated with each other. The second control valve 68 minimizes the opening degree of the extraction passage, and the check valve 84 blocks the extraction passage and the supply passage 58 so that the lubricating oil is discharged from the control pressure chamber 15 through the communication passage 90. There is no. Therefore, the lubricating oil in the control pressure chamber 15 is difficult to be discharged to the suction chamber 38 together with the refrigerant gas. Since the lubricating oil easily stays in the control pressure chamber 15, sufficient lubricating oil is retained in the control pressure chamber 15 to lubricate the sliding portion in the compressor.

The compressor of this embodiment has the following effects.
(1) The check valve body 86 of the check valve 84 opens the communication passage 90 when the pressure in the first passage 87 is higher than the pressure in the second passage 88, and the pressure in the first passage 87 is When the pressure in the two passages 88 is lower, the communication passage 90 is closed. For example, even when the liquid refrigerant is stored in the control pressure chamber 15 at the time of activation, the communication passage 90 is opened, so that the liquid refrigerant is a part of the air supply passage 58, the first passage 87, the communication passage. The air is discharged to the suction chamber 38, which is the suction pressure region, through 90 and the extraction passage. As a result, the liquid refrigerant can be discharged more quickly than when the liquid refrigerant is discharged only through the extraction passage at the time of activation. That is, by providing the communication passage 90 that connects the air supply passage 58 and the extraction passage, the liquid refrigerant stored in the control pressure chamber 15 at the time of activation can be quickly discharged to the suction chamber 38. Further, since the refrigerant supplied from the capacity control valve 59 passes through the check valve body 86 at the time of high rotation, the check valve body 86 closes the communication passage 90. By closing the communication passage 90, the lubricating oil is not discharged from the control pressure chamber 15 through the communication passage 90. As a result, an appropriate amount of lubricating oil can be maintained in the control pressure chamber 15.

(2) The passage sectional area of the communication passage 90 is smaller than the passage sectional area between the control pressure chamber 15 and the second control valve 68 in the supply passage 58. Therefore, when the liquid refrigerant is discharged to the suction chamber 38 through the first passage 87, the communication passage 90, and the extraction passage which are a part of the air supply passage 58, the liquid refrigerant is not subjected to the restriction by the communication passage 90 and smoothly. Liquid refrigerant can be passed.

(3) In the state where the compressor is installed, the air supply passage 58 is positioned below the extraction passage. Further, the air supply passage 58 is located below the extraction passage. Further, the path to the first passage 87, the communication passage 90, the space 64, the first connection passage 79, the second connection passage 80, and the suction chamber 38 is shorter than the length of the extraction passage. Therefore, at the time of starting the compressor, the liquid refrigerant in the control pressure chamber 15 is more discharged to the suction chamber 38 via the first passage 87 and the communication passage 90 than being discharged to the suction chamber 38 via the extraction passage. It is discharged in a short time.

(4) Since the extraction passage and the supply passage 58 are blocked during high rotation, only the extraction passage communicates with the suction chamber 38. For this reason, the lubricating oil in the control pressure chamber 15 can easily pass through the lubricating oil passage 26 at the time of high rotation, and the shaft seal device 22 can be cooled.

(5) By providing only one communication passage 90, it is possible to achieve both the suppression of lubricating oil discharge from the control pressure chamber 15 to the suction chamber 38 during high rotation and the promotion of discharge of liquid refrigerant from the control pressure chamber 15 during startup. . Further, only one communication passage 90 is provided, and there is no need to newly provide means or equipment for opening / closing control of the check valve 84. Therefore, the manufacturing cost of the compressor can be suppressed and the number of parts does not increase.

  The above embodiment shows an embodiment of the present invention, and the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the invention as described below. Is possible.

In the above embodiment, the check valve body 86 of the check valve 84 is controlled only by the differential pressure between the second passage 88 and the first passage 87, but this is not restrictive. For example, at least one of a first biasing spring that biases the check valve body 86 toward the valve forming plate 41 and a second biasing spring that biases toward the control pressure chamber 15 may be provided. That is, an urging spring may be added to open and close the valve body.
In the above embodiment, the connecting passage 90 is opened and closed by the outer peripheral surface of the check valve body 86 of the check valve 84, but this is not restrictive. For example, the communication passage may be formed so as to face the end face on the first passage 87 side of the check valve body 86, and the end face on the first passage 87 side may open and close the connection passage.
In the above embodiment, the suction chamber 38 is exemplified as the suction pressure region, but the suction pressure region is not limited to the suction chamber 38. The suction pressure region may be a region that maintains an atmosphere of suction pressure such as the suction passage 52 in addition to the suction chamber 38.
In the above embodiment, the hole diameter of the communication passage 90 is larger than the inner diameter of the first passage 87, but this is not restrictive. The hole diameter of the communication passage 90 may be smaller than the inner diameter of the first passage 87, or the hole diameter of the communication passage 90 and the inner diameter of the first passage 87 may be the same.

11 Cylinder block 12 Front housing 13 Rear housing 15 Control pressure chamber 17 Drive shaft 22 Shaft seal device 25 Swash plate 26 Lubricating oil passage 33 Cylinder bore 34 Piston 38 Suction chamber 39 Discharge chamber 54 External refrigerant circuit 59 Capacity control valve 62 In-shaft passage 63 Hole 64 Space portion 65 Housing passage 68 Second control valve 84 Check valve 85 Valve accommodating chamber 86 Check valve body 87 First passage 88 Second passage 89 Third passage 90 Connection passage 91 Large diameter valve portion 92 Small diameter valve portion 93 Through hole P Drive shaft center

Claims (2)

A housing having a suction chamber, a discharge chamber, a control pressure chamber and a plurality of cylinder bores;
A drive shaft rotatably supported by the housing;
A swash plate housed in the control pressure chamber, rotating integrally with the drive shaft, and tiltable with respect to the drive shaft;
A piston slidably accommodated in the cylinder bore, reciprocating in the cylinder bore in response to the rotational movement of the swash plate;
An air supply passage through which refrigerant in the discharge pressure region passes through the control pressure chamber;
A first control valve for adjusting a cross-sectional area of the air supply passage;
An extraction passage through which the refrigerant in the control pressure chamber passes through the suction pressure region;
A second control valve for adjusting a passage cross-sectional area of the extraction passage;
A check valve provided between the control pressure chamber and the first control valve in the air supply passage,
In the variable capacity swash plate compressor in which the stroke of the piston is adjusted by adjusting the pressure of the control pressure chamber,
The check valve is housed in a valve housing chamber provided in the housing, and includes a through hole through which the refrigerant supplied from the first control valve passes and a valve portion that regulates a reverse flow of refrigerant gas to the first control valve. Having a check valve body,
The housing communicates the communication passage that communicates the valve accommodating chamber and the extraction passage, the first passage that communicates the valve accommodating chamber and the control pressure chamber, and the valve accommodating chamber and the first control valve. A second passage,
The check valve body opens the communication passage when the pressure in the first passage is higher than the pressure in the second passage, and the pressure in the first passage is higher than the pressure in the second passage. A variable capacity swash plate compressor, wherein the communication passage is closed when it is low.   The variable displacement swash plate compressor according to claim 1, wherein a passage sectional area of the communication passage is larger than a passage sectional area of the first passage.

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