JP2009103075A - Single swash plate variable capacity compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a single swash plate variable capacity compressor capable of maintaining lubrication of a sliding portion by supplying lubricating oil to a crank chamber without introducing refrigerant gas returned from an external refrigerant circuit to the crank chamber. <P>SOLUTION: In this single swash plate variable capacity compressor 10, an intake muffler chamber 25 for the refrigerant gas returned from the external refrigerant circuit 40 is arranged on the upper periphery of a front housing 12 positioned to surround the crank chamber 15. The intake muffler chamber 25 and intake chamber 31 communicate with each other by an intake gas passage 51 not through the crank chamber 15. Further, an oil return hole 12b for returning the lubricating oil in the intake muffler chamber 25 to the crank chamber 15 is formed in the front housing 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a one-side swash plate type variable capacity compressor that constitutes a refrigeration circuit together with an external refrigerant circuit.

  A crank chamber in this type of one-side swash plate type variable displacement compressor (hereinafter simply referred to as a compressor) is partitioned in the housing. The cylinder bore is formed in a cylinder block constituting a part of the housing, and a piston is accommodated in the cylinder bore. The swash plate is supported by the rotating shaft in the crank chamber. The swash plate can rotate integrally with the rotation shaft and can tilt with respect to the rotation shaft. The piston is anchored to the swash plate through the shoe, and the piston is reciprocated in the cylinder bore by the rotation of the rotating shaft, and the refrigerant gas is compressed in the cylinder bore.

  Further, the discharge pressure region and the crank chamber in the compressor are connected via an air supply passage, and the crank chamber and the suction pressure region are connected via an extraction passage. The capacity control valve is interposed on the supply passage, for example. Then, the amount of refrigerant gas introduced into the crank chamber is changed by adjusting the opening of the air supply passage using the capacity control valve. Accordingly, the crank chamber pressure is changed, and the difference between the cylinder bore pressure and the piston is changed. As a result, the swash plate is tilted, the stroke of the piston is changed, and the discharge capacity is adjusted.

  In the crank chamber, lubrication of each sliding portion such as a shaft seal device or a bearing that slides between the piston and the shoe, between the shoe and the swash plate, and the peripheral surface of the rotating shaft is performed by the lubricating oil present in the crank chamber. The amount of lubricating oil present in the crank chamber greatly depends on the amount of blow-by gas containing lubricating oil that leaks from the cylinder bore to the crank chamber through the piston and cylinder bore (side clearance).

  However, if the side clearance is increased so as to increase the amount of blow-by gas leakage in order to maintain the lubrication of each sliding portion, problems such as a reduction in the performance of the compressor are undesirable. Therefore, in order to maintain the lubrication of each sliding portion, a compressor has been proposed in which a refrigerant gas containing lubricating oil is introduced into the muffler chamber, and the lubricating oil can be introduced into the sliding portion from the muffler chamber together with the refrigerant gas. (For example, refer to Patent Document 1).

In the compressor of Patent Document 1, a suction muffler chamber as the muffler chamber is formed across the outer surface of the front housing and the cylinder block. The suction muffler chamber communicates with a suction chamber (suction pressure region) formed in the rear housing through a passage. Further, a lubrication path is formed in the front housing from the suction muffler chamber to the shaft seal device and the bearing space around the rotation shaft (main shaft). A part of the refrigerant gas discharged from the compression chamber flows into the crank chamber through the capacity control valve and the air supply passage. The refrigerant gas (discharge gas) that has flowed into the crank chamber passes through the gap between the rotating shaft and the bearing, reaches the space between the shaft seal device and the bearing, and is further introduced into the muffler chamber via the lubrication path. . As a result, the lubricating oil contained in the refrigerant gas adheres to the shaft seal device and the bearing and is lubricated.
JP 2000-303950 A

  However, in the compressor of Patent Document 1, lubrication of the shaft seal device and the bearing is performed by lubricating oil contained in the refrigerant gas after discharge. Since the refrigerant gas after discharge is a high-temperature gas immediately after compression, the lubricating oil contained in the refrigerant gas after discharge is also at a high temperature. Therefore, the viscosity of the lubricating oil decreases, and it becomes difficult to maintain lubrication at each sliding portion. For this reason, refrigerant gas having a temperature lower than that of the refrigerant gas after discharge, that is, refrigerant gas returned from the external refrigerant circuit is introduced into the crank chamber, and lubrication having a higher viscosity than the lubricating oil contained in the refrigerant gas after discharge is performed. A compressor that maintains lubrication of each sliding portion with oil has also been proposed. However, in a variable capacity compressor, the pressure in the crank chamber is adjusted to adjust the discharge capacity. For this reason, it is necessary to control the pressure in the crank chamber in order to adjust the discharge capacity to the control target while introducing the refrigerant gas returned from the external refrigerant circuit to lubricate the sliding portion into the crank chamber.

  The present invention has been made paying attention to the problems existing in the above prior art, and its purpose is to supply lubricating oil to the crank chamber without introducing the refrigerant gas returned from the external refrigerant circuit into the crank chamber. Another object of the present invention is to provide a one-side swash plate type variable capacity compressor capable of maintaining the lubrication of the sliding portion.

  In order to solve the above problems, the invention according to claim 1 is characterized in that a rotating shaft is rotatably supported by a housing in which a front housing and a rear housing are joined to a cylinder block, and the rotating shaft of the cylinder block is A plurality of cylinder bores are disposed in the periphery, and a swash plate that rotates integrally with the rotary shaft is housed in a crank chamber defined between the cylinder block and the front housing so as to be tiltable, and is anchored to the swash plate. The refrigerant gas sucked from the suction pressure region is compressed in the cylinder bore by the movement of the piston in the cylinder bore accompanying the rotation of the rotating shaft, and the inclination angle of the swash plate is adjusted by the pressure regulation of the crank chamber. Is changed so that the discharge capacity is controlled and the one side swash plate type variable capacity pressure that forms the refrigeration circuit together with the external refrigerant circuit A suction muffler chamber for the refrigerant gas returning from the external refrigerant circuit is provided on an upper outer periphery of a front housing at a position surrounding the crank chamber, and the suction muffler chamber and the suction pressure region are cranked. An oil return hole is formed in the front housing to communicate with the suction gas passage without passing through the chamber, and to connect the suction muffler chamber and the crank chamber and return the lubricating oil in the suction muffler chamber to the crank chamber. Yes.

  According to this invention, the refrigerant gas returned from the external refrigerant circuit to the one-side swash plate type variable capacity compressor is not introduced into the crank chamber but is introduced into the suction muffler chamber. Since the refrigerant gas introduced into the suction muffler chamber has a lower temperature than the refrigerant gas discharged from the cylinder bore, the lubricating oil contained in the refrigerant gas in the suction muffler chamber is also included in the discharged refrigerant gas. It becomes colder than. Since the suction muffler chamber is formed on the outer periphery of the upper part of the crank chamber, the lubricating oil is dropped by the dead weight through the oil return hole from the suction muffler chamber to the crank chamber, and the low temperature lubricating oil is passed through the oil return hole to the crank chamber. Can be supplied to. Therefore, the low temperature lubricating oil can be supplied to each sliding portion in the crank chamber, and the lubrication of each sliding portion can be maintained. The refrigerant gas introduced into the suction muffler chamber is led out to the suction pressure region through the suction gas passage without passing through the crank chamber. Therefore, the refrigerant gas introduced into the suction muffler chamber for maintaining lubrication does not affect the adjustment of the discharge capacity of the one-side swash plate type variable displacement compressor, and the crank chamber for maintaining both lubrication and capacity adjustment. There is no need for pressure control.

The suction muffler chamber may be provided with an oil separator that separates lubricating oil contained in the refrigerant gas.
According to this, the lubricating oil can be efficiently separated from the refrigerant gas introduced into the suction muffler chamber, and the amount of lubricating oil that can be supplied to the crank chamber is increased as compared with the case where no oil separator is provided. Can do.

Further, the opening degree of the oil return hole may be adjustable by an electromagnetic valve.
According to this, the supply amount of the lubricating oil to the crank chamber can be adjusted in accordance with the lubrication state of each sliding portion depending on the operation state of the one-side swash plate type variable displacement compressor.

  In addition, a part of the intake gas passage has a venturi structure, and a throat portion in the venturi structure forms a low pressure region lower in pressure than the external refrigerant circuit, and an oil return passage from the external refrigerant circuit serves as the throat It may be connected to the part.

  According to this, the lubricating oil accumulated in the external refrigerant circuit can be pumped toward the throat portion based on the pressure difference between the external refrigerant circuit and the throat portion. As a result, the lubricating oil adhering to the external refrigerant circuit device in the refrigeration circuit can be recovered, and a decrease in cooling capacity due to the adhering lubricating oil can be suppressed.

Further, a part of the intake gas passage may be formed so as to extend along the outer peripheral surface of the cylinder block.
According to this, the refrigerant gas having a temperature lower than that of the discharged refrigerant gas comes into contact with the outer peripheral surface of the cylinder block. Therefore, the cylinder block can be cooled by the low-temperature refrigerant gas.

  According to the present invention, the lubricating oil can be supplied to the crank chamber and the lubrication of the sliding portion can be maintained without introducing the refrigerant gas returned from the external refrigerant circuit into the crank chamber.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In the following description, “front” and “rear” of the one-side swash plate type variable displacement compressor 10 (hereinafter simply referred to as “compressor 10”) have the direction of the arrow Y1 shown in FIG. "And" down "are the directions of the arrow Y2 shown in FIG.

  As shown in FIG. 1, the housing of the compressor 10 includes a cylinder block 11, a front housing 12 joined and fixed to the front end (one end) of the cylinder block 11, and a valve / The rear housing 14 is joined and fixed via a port forming body 13. The cylinder block 11, the front housing 12, and the rear housing 14 are fastened together by a plurality of bolts B (see FIG. 2). The cylinder block 11 is made of a high-strength, wear-resistant aluminum die cast material (containing high silicon). A crank chamber 15 is defined in a region surrounded by the cylinder block 11 and the front housing 12. A rotary shaft 16 is rotatably supported by the front housing 12 and the cylinder block 11, and the rotary shaft 16 is rotatably arranged in the crank chamber 15. In the crank chamber 15, a lug plate 21 is fixed to the rotary shaft 16 so as to be integrally rotatable.

  An engine (internal combustion engine) E serving as a travel drive source of the vehicle is operatively connected to a front end portion of the rotary shaft 16 outside the compressor 10 through a power transmission mechanism (not shown). A thrust bearing 17 is interposed between the front housing 12 and the lug plate 21, and between the inner peripheral surfaces of the front housing 12 and the cylinder block 11 and the peripheral surfaces on both the front and rear sides of the rotary shaft 16. A radial bearing 30 is interposed in each case. Further, a storage chamber 39 is formed between the front peripheral surface of the rotating shaft 16 and the inner peripheral surface of the front housing 12, and a lip seal type shaft seal device 47 made of a rubber material is formed in the storage chamber 39. Is housed. The front housing 12 is formed with an introduction passage 48 that allows the storage chamber 39 and the crank chamber 15 to communicate with each other.

  A swash plate 22 is accommodated in the crank chamber 15. The swash plate 22 is supported by the rotating shaft 16 so as to be slidable and tiltable. The hinge mechanism 23 is interposed between the lug plate 21 and the swash plate 22. Therefore, the swash plate 22 can be rotated synchronously with the lug plate 21 and the rotary shaft 16 by the hinge connection with the lug plate 21 via the hinge mechanism 23 and the support of the rotary shaft 16. It is possible to tilt with respect to the rotating shaft 16 while being accompanied by a sliding movement in the axial direction.

  A plurality of cylinder bores 11 a are formed in the cylinder block 11 so as to surround the rotating shaft 16. The single-headed piston 20 is accommodated in each cylinder bore 11a so as to be able to reciprocate. The front and rear openings of the cylinder bore 11a are closed by the valve / port forming body 13 and the piston 20, and a compression chamber 28 whose volume is changed according to the reciprocation of the piston 20 is defined in the cylinder bore 11a. Each piston 20 is anchored to the outer peripheral portion of the swash plate 22 via a shoe 29. Therefore, the rotational motion of the swash plate 22 accompanying the rotation of the rotating shaft 16 is converted into the reciprocating linear motion of the piston 20 via the shoe 29.

  A suction chamber 31 that forms a suction pressure region and a discharge chamber 32 that forms a discharge pressure region are defined between the valve / port forming body 13 and the rear housing 14. Corresponding to each compression chamber 28, the valve / port forming body 13 includes a suction port 33, a suction valve 34 that opens and closes the suction port 33, and a discharge port 35 and a discharge valve 36 that opens and closes the discharge port 35. Is formed.

  A suction muffler chamber forming portion 12 a having a box shape opening upward is provided on the upper outer peripheral surface of the front housing 12. The upper opening of the suction muffler chamber forming portion 12a is closed by a lid member 24, and the suction muffler chamber 25 is partitioned by the suction muffler chamber forming portion 12a and the lid member 24. Therefore, the suction muffler chamber 25 is located above the crank chamber 15 (upper outer periphery) via the peripheral wall of the front housing 12.

  As shown in FIGS. 2 and 3, the cylinder block 11 and the rear housing 14 are formed with a passage forming portion 50 having one end connected to the suction muffler chamber forming portion 12a and the other end connected to the rear housing 14. Has been. The passage forming portion 50 is formed so as to extend straight from the front housing 12 toward the rear housing 14 along the outer peripheral surface of the cylinder block 11. As shown in FIGS. 1 to 3, a suction gas passage 51 that connects the suction muffler chamber 25 and the suction chamber 31 is formed in the suction muffler chamber forming portion 12 a, the passage forming portion 50, and the rear housing 14. Has been. The intake gas passage 51 extends along the outer peripheral surface of the cylinder block 11 and is formed in the rear housing 14.

  As shown in FIG. 1, a discharge muffler chamber forming portion 14 a having a box shape opening upward is erected on an upper outer peripheral surface of the rear housing 14. The upper opening of the discharge muffler chamber forming portion 14 a is closed by the lid member 18, and the discharge muffler chamber forming portion 14 a and the lid member 18 define the discharge muffler chamber 19. The discharge muffler chamber 19 communicates with the discharge chamber 32 through the discharge passage 27.

  The compressor 10 having the above configuration constitutes a refrigerant circulation circuit (refrigeration circuit) of the vehicle air conditioner together with the external refrigerant circuit 40. The external refrigerant circuit 40 includes, for example, a gas cooler 41, an expansion valve 42, and an evaporator 43. In the downstream area of the external refrigerant circuit 40, a downstream-side circulation pipe 45 that communicates the outlet of the evaporator 43 and the inlet 25a of the suction muffler chamber 25 is provided. The inlet 25a of the suction muffler chamber 25 is formed in the lid member 24 and opens upward. Further, in the upstream area of the external refrigerant circuit 40, an upstream-side circulation pipe 46 that connects the outlet 19 a of the discharge muffler chamber 19 and the inlet of the gas cooler 41 is provided.

  In this refrigeration circuit, the refrigerant gas compressed by the compressor 10 is cooled by the gas cooler 41 to become a high-pressure liquid refrigerant, is decompressed by the expansion valve 42, and is vaporized at a low temperature by the evaporator 43. For this reason, the refrigerant gas returning from the evaporator 43 to the suction muffler chamber 25 is at a lower temperature than the refrigerant gas discharged from the compressor 10.

  In the compressor 10, the refrigerant gas is introduced from the downstream area of the external refrigerant circuit 40 into the suction chamber 31 through the suction muffler chamber 25 and the suction gas passage 51. The refrigerant gas in the suction chamber 31 is sucked into the cylinder bore 11a (compression chamber 28) through the suction port 33 and the suction valve 34 by the movement from the top dead center position to the bottom dead center position side of each piston 20. . The refrigerant gas sucked into the compression chamber 28 is compressed to a predetermined pressure by movement from the bottom dead center position of the piston 20 to the top dead center position side, and then is discharged through the discharge port 35 and the discharge valve 36. 32 is discharged. The refrigerant gas discharged into the discharge chamber 32 is introduced into the discharge muffler chamber 19.

  Further, the inclination angle of the swash plate 22 in the compressor 10 (the angle formed between the plane perpendicular to the axis of the rotary shaft 16) is changed according to the change (regulation) of the pressure in the crank chamber 15. . The pressure control of the crank chamber 15 is performed by a discharge passage 37, an air supply passage 38, and a flow rate control valve CV provided in the compressor 10. The discharge passage 37 communicates the crank chamber 15 and the suction chamber 31. The air supply passage 38 communicates the crank chamber 15 and the discharge chamber 32. A flow control valve CV is disposed in the middle of the air supply passage 38, and the flow control valve CV can adjust the opening degree of the air supply passage 38.

  The amount of high-pressure refrigerant gas introduced into the crank chamber 15 via the air supply passage 38 is adjusted by the flow control valve CV, and the amount of refrigerant gas derived from the crank chamber 15 via the discharge passage 37 is adjusted. The balance is controlled, and the pressure in the crank chamber 15 is determined (regulated). As a result of the inclination angle of the swash plate 22 being changed in accordance with the change in the pressure in the crank chamber 15, the stroke of the piston 20, that is, the discharge capacity of the compressor 10 is adjusted.

Next, the lubrication structure in the compressor 10 will be described.
The suction muffler chamber forming portion 12 a that forms the bottom of the suction muffler chamber 25 is formed with an oil return hole 12 b that communicates the suction muffler chamber 25 and the crank chamber 15. The oil return hole 12b extends in the vertical direction so as to pass through the peripheral wall of the front housing 12, the upper end of the oil return hole 12b opens toward the suction muffler chamber 25, and the lower end of the oil return hole 12b extends to the crank chamber 15. Open towards. Further, the oil return hole 12 b is located above the hinge mechanism 23.

  As shown in FIG. 4, a venturi pipe structure 52 is constructed at a location located in the outer peripheral portion of the cylinder block 11 in the intake gas passage 51. The venturi structure 52 includes a nozzle portion 52 a that gradually reduces the diameter of the suction gas passage 51 from the suction muffler chamber 25 toward the suction chamber 31, a throat portion 52 b that has the smallest diameter, and a throat portion 52 b in the suction chamber 31. And a diffuser portion 52c that gradually increases in diameter. And in the channel | path formation part 50, the through-hole 50a is formed in the position facing the throat part 52b, and the oil return channel | path 53 connected to the evaporator 43 is connected to this through-hole 50a.

  Now, in the compressor 10 having the above lubricating structure, the refrigerant gas returns from the downstream area of the external refrigerant circuit 40 to the suction muffler chamber 25. The lubricating oil contained in the refrigerant gas returned to the suction muffler chamber 25 is separated from the refrigerant gas by colliding with the inner surface of the suction muffler chamber 25 and stored in the suction muffler chamber 25. The lubricating oil stored in the suction muffler chamber 25 passes through the oil return hole 12b by its own weight and is dropped from the suction muffler chamber 25 to the crank chamber 15. Therefore, the lubricating oil contained in the refrigerant gas having a temperature lower than that of the discharged refrigerant gas is supplied to the crank chamber 15. That is, lubricating oil having a low viscosity and a low lubricity is supplied to the crank chamber 15. Then, lubricating oil is directly supplied between the piston 20 and the shoe 29, between the swash plate 22 and the shoe 29, and to the thrust bearing 17. Lubricating oil is supplied from the crank chamber 15 to the accommodating chamber 39 via the introduction passage 48, and is supplied to the radial bearing 30 on the front side and the shaft seal device 47, and lubrication of each sliding portion is maintained. The

  The refrigerant gas introduced into the suction muffler chamber 25 passes through the suction gas passage 51 and is sucked into the suction chamber 31. At this time, as the refrigerant gas passes through the venturi tube structure 52, the pressure energy is converted into velocity energy by the nozzle portion 52a, and flows into the throat portion 52b as high-speed and low-pressure refrigerant gas. The high-speed and low-pressure refrigerant gas that has passed through the throat part 52b is converted into pressure energy in the diffuser part 52c, recovered to low-speed and high-pressure gas, and flows into the suction chamber 31.

  Therefore, the pressure in the throat portion 52b becomes lower than the pressure in the evaporator 43, and a low pressure region that is lower in pressure than the external refrigerant circuit 40 (evaporator 43) is formed by the throat portion 52b. Therefore, the lubricating oil accumulated in the evaporator 43 is pumped toward the throat part 52b based on the pressure difference between the evaporator 43 and the throat part 52b, and returned to the suction chamber 31 together with the refrigerant gas passing through the throat part 52b. It is. Therefore, a sufficient amount of lubricating oil is always secured in the compressor 10.

According to the above embodiment, the following effects can be obtained.
(1) A suction muffler chamber 25 is formed on the outer periphery of the upper portion of the front housing 12 so as to be positioned above the crank chamber 15, and an oil return hole 12 b that connects the suction muffler chamber 25 and the crank chamber 15 is formed. Further, the suction muffler chamber 25 and the suction chamber 31 are communicated with each other through the suction gas passage 51 without passing through the crank chamber 15. Therefore, low-temperature lubricating oil contained in the refrigerant gas returned from the external refrigerant circuit 40 to the suction muffler chamber 25 can be supplied to the crank chamber 15 from the oil return hole 12b, and each sliding portion in the crank chamber 15 can be supplied. Can maintain the lubrication. In addition, since it is not necessary to introduce the refrigerant gas returned from the external refrigerant circuit 40 into the crank chamber 15, there is no influence on the pressure adjustment of the crank chamber 15 for adjusting the discharge capacity of the compressor 10, and lubrication maintenance and capacity adjustment are performed. Therefore, it is not necessary to control the pressure in the crank chamber 15 to achieve both.

  (2) As a result of forming the oil return hole 12b in the front housing 12 so that the lubricating oil can be supplied from the suction muffler chamber 25 to the crank chamber 15, the blow-by gas from the compression chamber 28 to the crank chamber 15 is increased. There is no need to increase the supply of lubricating oil. Therefore, it is not necessary to increase the side clearance between the piston 20 and the cylinder bore 11a in order to increase the blow-by gas. Therefore, in addition to being able to suppress a decrease in the performance of the compressor 10 due to an increase in blow-by gas accompanying an increase in side clearance, when the compressor 10 needs to be operated at 100% capacity, the increase in blow-by gas causes the crank chamber 15 to increase. It is possible to prevent a problem that the operating state changes due to a change in pressure.

  (3) Further, as a result of forming the oil return hole 12b in the front housing 12 and allowing the lubricating oil to be supplied from the suction muffler chamber 25 to the crank chamber 15, the lubrication contained in the refrigerant gas immediately after being discharged from the compression chamber 28 The shaft seal device 47 is cooled by low-temperature lubricating oil as compared with oil. For this reason, it is possible to prevent the shaft seal device 47 from exceeding the heat resistance temperature, and to avoid the operation stop of the compressor 10 due to the heat resistance temperature of the shaft seal device 47 being exceeded. Further, the low-temperature lubricating oil supplied to the crank chamber 15 adheres to the inner surface of the crank chamber 15 and cools the front housing 12. For this reason, the tightening margin of the radial bearing 30 press-fitted into the front housing 12 is suppressed from being loosened due to thermal expansion, and noise caused by widening of the gap between the peripheral surface of the rotary shaft 16 and the inner peripheral surface of the radial bearing 30 is suppressed. Occurrence can be suppressed.

  (4) In the compressor 10, the lubricating oil present in the crank chamber 15 is agitated by the rotating swash plate 22 or the like to become mist and mixed with the refrigerant gas. When the refrigerant gas is supplied from the discharge chamber 32 (discharge pressure region) to the crank chamber 15 to increase the pressure of the crank chamber 15, the amount of refrigerant gas flowing from the discharge chamber 32 to the suction chamber 31 via the crank chamber 15 is increased. As the refrigerant gas increases, a large amount of lubricating oil flows from the crank chamber 15 to the suction chamber 31. However, in the present embodiment, since the lubricating oil stored in the suction muffler chamber 25 can be supplied to the crank chamber 15, the lubricating oil can be secured in the crank chamber 15. As a result, it is possible to suppress the oil rate of the refrigeration circuit by suppressing the amount of lubricating oil present in the compressor 10 for lubrication of each sliding portion, and to suppress the decrease in cooling capacity accompanying the increase in oil rate. it can.

  (5) A part of the suction gas passage 51 communicating the suction muffler chamber 25 and the suction chamber 31 is formed so as to extend along the outer peripheral surfaces of the cylinder block 11 and the rear housing 14. Therefore, a refrigerant gas having a temperature lower than that of the refrigerant gas immediately after being discharged from the compression chamber 28 flows in the vicinity of the outer peripheral surfaces of the cylinder block 11 and the front housing 12. Therefore, the cylinder block 11 can be cooled by the low-temperature refrigerant gas, and deformation of the cylinder bore 11a due to thermal expansion can be suppressed. Therefore, a high-strength, wear-resistant aluminum die-cast material (containing high silicon) can be used for the cylinder block 11, and the compressor block 10 is lightened by reducing the thickness and weight of the cylinder block 11, thereby reducing the weight of the vehicle. In addition, the wear resistance of the cylinder bore 11a can be improved.

  (6) In the present embodiment, a discharge muffler chamber 19 is formed in the rear housing 14. For this reason, as compared with the case where the discharge muffler chamber 19 is formed in the cylinder block 11, there is no portion where the rigidity of the cylinder bore 11 a is extremely strong in the cylinder block 11. Therefore, the cylinder bore 11a is easily deformed by thermal expansion, and even if the piston 20 is slidably contacted with the cylinder bore 11a, the cylinder bore 11a is deformed following the sliding of the piston 20 and contributes to friction reduction by increasing the sliding contact area. be able to.

  (7) A venturi structure 52 is formed in the intake gas passage 51. The throat portion 52 b of the venturi pipe structure 52 is connected to the evaporator 43 via the oil return passage 53. For this reason, the lubricating oil accumulated in the evaporator 43 can be pumped toward the throat portion 52b based on the pressure difference between the evaporator 43 and the throat portion 52b. As a result, the lubricating oil adhering to the evaporator 43 of the external refrigerant circuit 40 in the refrigeration circuit can be recovered, and a decrease in cooling capacity due to the adhering lubricating oil can be suppressed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. Note that in the second embodiment described below, the same components as those in the first embodiment described above are denoted by the same reference numerals, and redundant description thereof is omitted or simplified.

  As shown in FIG. 5, in the front housing 12 of the compressor 10, a mounting hole 12c is formed on the side surface of the suction muffler chamber forming portion 12a, and an electromagnetic valve 55 is mounted in the mounting hole 12c. And the valve body 56 of the electromagnetic valve 55 can adjust the opening degree of the oil return hole 12b.

  The electromagnetic valve 55 has a valve body 56, and a movable iron core 57 is connected to the valve body 56. The electromagnetic valve 55 has a fixed iron core 58 and is disposed to face the movable iron core 57. The electromagnetic valve 55 includes a coil 59, and a biasing spring 60 that biases the movable iron core 57 in a direction away from the fixed iron core 58 is disposed between the valve body 56 and the coil 59.

  The coil 59 is supplied with electric power based on a command from an air conditioner ECU (not shown). Accordingly, an electromagnetic urging force (electromagnetic force) having a magnitude corresponding to the amount of power supplied to the coil 59 is generated between the movable iron core 57 and the fixed iron core 58, and this electromagnetic urging force is transmitted through the movable iron core 57 to the valve body. 56, and urges the valve body 56 in a direction to open the oil return hole 12b. When there is no power supply to the coil 59, the valve body 56 is disposed at a position where the half of the oil return hole 12 b is closed by the biasing force of the biasing spring 60.

  An oil separator 61 is disposed in the suction muffler chamber 25. The oil separator 61 has a substantially conical cylindrical shape, and is disposed in the suction muffler chamber 25 so as to reduce the diameter from the upper end toward the lower end. The lower end opening of the oil separator 61 opens toward the inlet 25a formed on the side surface of the suction muffler chamber forming portion 12a, and the refrigerant gas introduced into the suction muffler chamber 25 from the inlet 25a is transferred to the oil separator 61. Has been introduced in.

  In the compressor 10 of the second embodiment, when the refrigerant gas returned from the external refrigerant circuit 40 is introduced into the suction muffler chamber 25, the refrigerant gas that has passed through the inlet 25a flows toward the oil separator 61. Furthermore, it rises while turning along the inner peripheral surface of the oil separator 61. At this time, the lubricating oil contained in the refrigerant gas is separated from the refrigerant gas by centrifugal force, and drops into the suction muffler chamber 25 by its own weight.

  The lubricating oil in the suction muffler chamber 25 is supplied to the crank chamber 15 through the oil return hole 12b. In the compressor 10, the amount of lubricating oil supplied to the crank chamber 15 can be adjusted by adjusting the opening of the oil return hole 12 b by the electromagnetic valve 55. For example, when the rotational state of the rotary shaft 16 is low and the lubrication state of each sliding portion becomes severe, such as when the discharge pressure is low, the electromagnetic valve 55 is controlled by the air conditioner ECU (to the coil 59). Adjust the power supply amount) to increase the opening of the oil return hole 12b.

Therefore, according to 2nd Embodiment, in addition to the effect similar to (1)-(7) as described in 1st Embodiment, the following effects can be acquired.
(8) In the second embodiment, the opening degree of the oil return hole 12 b can be adjusted by the electromagnetic valve 55. For this reason, the supply amount of the lubricating oil to the crank chamber 15 can be adjusted in accordance with the lubrication state of each sliding portion depending on the operation state of the compressor 10. Therefore, the lubrication state in each sliding part can always be maintained in a good state.

  (9) In the second embodiment, the oil separator 61 is provided in the suction muffler chamber 25. Therefore, the lubricating oil can be efficiently separated from the refrigerant gas introduced into the suction muffler chamber 25, and the amount of lubricating oil that can be supplied to the crank chamber 15 is increased as compared with the case where the oil separator 61 is not provided. be able to.

Each embodiment may be changed as follows.
As shown in FIG. 6, the electromagnetic valve 55 may not be provided in the second embodiment.
In the second embodiment, the oil separator 61 may be an inertia separation type instead of a centrifugal separation type.

In the first embodiment, an electromagnetic valve 55 may be provided in the suction muffler chamber 25 so that the opening degree of the oil return hole 12b can be adjusted.
In each embodiment, the passage forming portion 50 may be formed to extend in an arc shape along the peripheral surface of the cylinder block 11.

  In each embodiment, the throat portion 52 b of the venturi tube structure 52 may be connected to other portions via the oil return passage 53 instead of the evaporator 43. For example, the throat portion 52 b in the venturi pipe structure 52 and the gas cooler 41 may be connected by the oil return passage 53 so that the lubricating oil accumulated in the gas cooler 41 can be returned to the intake gas passage 51.

  In each embodiment, the rotary shaft 16 may be provided with a rotary valve, and the rotary valve may be communicated with the suction chamber 31 so that refrigerant gas is sucked into the cylinder bore 11a (compression chamber 28) via the rotary valve.

The longitudinal cross-sectional view which shows the one-side swash plate type variable capacity compressor of 1st Embodiment. The top view which shows a one-side swash plate type variable capacity compressor. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 1 showing an intake gas passage. The partial expanded sectional view which shows a venturi pipe structure. The fragmentary longitudinal cross-section which shows the one side swash plate type | mold variable capacity compressor of 2nd Embodiment. The fragmentary longitudinal cross-section which shows the other example of the one-side swash plate type variable capacity compressor of 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Single side swash plate type variable capacity compressor, 11 ... Cylinder block, 11a ... Cylinder bore, 12 ... Front housing, 12b ... Oil return hole, 14 ... Rear housing, 15 ... Crank chamber, 16 ... Rotating shaft, 20 ... Piston, 22 DESCRIPTION OF SYMBOLS ... Swash plate, 25 ... Suction muffler chamber, 31 ... Suction chamber as suction pressure area, 40 ... External refrigerant circuit, 51 ... Suction gas passage, 52 ... Venturi pipe structure, 52b ... Throat part, 53 ... Oil return passage, 55 ... solenoid valve, 61 ... oil separator.

Claims (5)

A rotating shaft is rotatably supported by a housing in which a front housing and a rear housing are joined to a cylinder block, a plurality of cylinder bores are disposed around the rotating shaft in the cylinder block, and the cylinder block and the front housing A swash plate that rotates integrally with the rotary shaft is accommodated in a crank chamber partitioned between the rotary shaft and a piston moored to the swash plate by movement in the cylinder bore as the rotary shaft rotates. The refrigerant gas sucked from the suction pressure region is configured to be compressed in the cylinder bore, and the inclination angle of the swash plate is changed by adjusting the pressure of the crank chamber to control the discharge capacity, and the refrigeration circuit is configured together with the external refrigerant circuit One side swash plate type variable capacity compressor
A suction muffler chamber for refrigerant gas returning from the external refrigerant circuit is provided on the outer periphery of the upper portion of the front housing at a position surrounding the crank chamber, and the suction muffler chamber and the suction pressure region do not pass through the crank chamber. A one-sided swash plate type variable in which the suction housing is connected to the suction muffler chamber, and the suction muffler chamber and the crank chamber are connected to each other. Capacity compressor.   The one-side swash plate type variable capacity compressor according to claim 1, wherein an oil separator for separating lubricating oil contained in the refrigerant gas is provided in the suction muffler chamber.   The one-side swash plate type variable capacity compressor according to claim 1 or 2, wherein the opening degree of the oil return hole is adjustable by an electromagnetic valve.   A part of the intake gas passage has a venturi structure, and a low pressure region lower than the external refrigerant circuit is formed by a throat portion in the venturi pipe structure, and an oil return passage from the external refrigerant circuit is formed in the throat portion. The one side swash plate type variable capacity compressor as described in any one of Claims 1-3 connected.   5. The one-side swash plate variable displacement compressor according to claim 1, wherein a part of the intake gas passage is formed to extend along an outer peripheral surface of the cylinder block.

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