JP2009209739A - Swash plate compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a swash plate compressor capable of realizing demonstration of an excellent sliding characteristic when a drive shaft is rotated at high speed, and of a high refrigerating capacity when the drive shaft is rotated at low speed. <P>SOLUTION: In the swash plate compressor, an oil guide groove 3b, an oil guide hole 3c, a first hole 37, an outflow hole 39, a valve hole 41, a communication port 49b, a receiving chamber 1c, a throttle hole 9a and a second hole 55 constitute a release passage. The oil guide groove 3b, the oil guide hole 3c, the first hole 37, the outflow hole 39, the valve hole 41, the communication port 49b, the receiving chamber 1c and the throttle hole 9a constitute a first passage. Also, the second hole 55 constitutes a second passage. An open close valve 45 increases a ratio, at which the first passage occupies the release passage, as a drive shaft 7 is increased in rotating speed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a swash plate compressor.

  Patent Document 1 discloses a conventional swash plate compressor. In the swash plate compressor, a housing is constituted by a front housing, a cylinder block, and a rear housing, and a plurality of cylinder bores, a suction chamber, a discharge chamber, and a crank chamber are formed by the housing. One end of the front housing is exposed from the front housing, and a drive shaft facing the crank chamber is rotatably supported. In the crank chamber, the swash plate is supported by the drive shaft so that the tilt angle can be varied. A piston is housed in each cylinder bore so as to be able to reciprocate. A pair of front and rear shoes is provided between the swash plate and each piston, and the swing motion of the swash plate is converted into the reciprocating motion of each piston by each pair of shoes. The discharge chamber and the crank chamber communicate with each other through an air supply passage, and a capacity control valve for adjusting the pressure in the crank chamber is provided on the air supply passage.

  Further, in this swash plate type compressor, an escape passage is formed for communicating the crank chamber with the suction chamber. In the swash plate compressor of Patent Document 1, the escape passage has a first diameter hole formed to extend in the radial direction of the drive shaft, and an outflow hole that allows the first diameter hole to communicate with the suction chamber. A lug plate is fixed to the drive shaft so as to rotate integrally, and an oil supply passage extending from the outer peripheral region of the crank chamber toward the center side is formed in the lug plate. Further, a shaft seal device for sealing the drive shaft exposed from the front housing is provided between the front housing and the drive shaft, and the oil supply passage is provided in the front housing with the first diameter via the shaft seal device. A lubrication passage communicating with the hole is formed.

  This swash plate type compressor constitutes a refrigeration circuit together with a condenser, an expansion valve and an evaporator, and this refrigeration circuit can be used for an air conditioner of a vehicle. In this swash plate type compressor, the capacity control valve adjusts the pressure in the crank chamber based on the pressure in the suction chamber and the flow rate of the refrigerant gas, and changes the angle of the swash plate with respect to the drive shaft to reduce the discharge capacity. It has changed.

  Further, in this swash plate compressor, the outer peripheral region of the crank chamber is a region where there is a lot of lubricating oil in the crank chamber, and the escape passage composed of the oil supply passage, the lubricating passage, the first diameter hole, and the outflow hole is used for the lubricating oil. Since it communicates with many areas, the lubricating oil in the crank chamber can be suitably supplied to the shaft seal device, and the durability of the rubber material of the shaft seal device can be improved.

JP-A-8-284816

  By the way, in the swash plate type compressor, when the drive shaft is rotated at a high speed, it is required to improve the sliding characteristics at sliding portions such as between the cylinder bore and the piston, and between the swash plate and each shoe. Further, when the drive shaft is rotated at a low speed, it is required to reduce the amount of lubricating oil in the refrigerant gas discharged to the refrigeration circuit outside the swash plate compressor and to exhibit a high refrigeration capacity.

  In this respect, the swash plate compressor disclosed in Patent Document 1 has a relief passage that communicates with a region where there is a lot of lubricating oil in the crank chamber, and the crank chamber and the suction chamber communicate with each other with the same cross-sectional area. Regardless of the rotation speed, the amount of lubricating oil in the crank chamber is made too small or excessive. If the amount of lubricating oil in the crank chamber is excessive while the rotational speed of the drive shaft increases, the swash plate or the like will stir the lubricating oil excessively, the lubricating oil will likely generate heat due to shearing, and the viscosity of the lubricating oil will tend to decrease. . In this case, there is a concern about lubrication of the sliding part. In addition, if the amount of lubricating oil in the crank chamber is too small while the rotational speed of the drive shaft is reduced, the amount of lubricating oil in the refrigerant gas discharged to the refrigeration circuit outside the swash plate compressor increases, and the refrigerating capacity increases. It becomes insufficient.

  The present invention has been made in view of the above-described conventional situation, and exhibits excellent sliding characteristics when the drive shaft is rotated at a high speed, and a high refrigeration capacity when the drive shaft is rotated at a low speed. It is an issue to be solved to provide a swash plate compressor capable of realizing the above.

  The swash plate compressor employs refrigerant gas mixed with lubricating oil. According to the test results of the inventors, the crank chamber of the swash plate compressor has a region with a large amount of lubricating oil and a region with a small amount of lubricating oil. For example, the region where the amount of lubricating oil in the crank chamber is high is the outer peripheral region of the crank chamber, and the region where the lubricating oil is low in the crank chamber is the inner peripheral region of the crank chamber, that is, a portion away from the wall surface of the crank chamber. This is because the swash plate or the like rotates together with the drive shaft in the crank chamber, and the lubricating oil is pushed to the outer peripheral area of the crank chamber by centrifugal force. Further, the bottom side of the crank chamber and the surface around the cylinder bore in the crank chamber are regions with a lot of lubricating oil. On the other hand, the upper side of the crank chamber is a region where there is little lubricating oil. The present invention has been completed based on this confirmation.

The swash plate compressor according to the present invention includes a housing having a cylinder bore, a suction chamber, a discharge chamber, and a crank chamber, a drive shaft that is rotatably supported by the housing and faces the crank chamber, and the drive shaft in the crank chamber. A swash plate supported by the cylinder, a piston accommodated in the cylinder bore so as to be reciprocally movable, and provided between the swash plate and the piston, and the swinging motion of the swash plate is converted into a reciprocating motion of the piston. In a swash plate type compressor comprising a motion conversion mechanism that performs the above and a relief passage that allows the crank chamber to communicate with the suction chamber.
The escape passage has a first passage communicating with a region where the lubricating oil in the crank chamber is large,
An on-off valve is provided to increase the opening of the first passage by increasing the rotational speed of the drive shaft (Claim 1).

  In the swash plate compressor of the present invention, when the drive shaft is rotated at a high speed, the on-off valve increases the opening of the first passage. For this reason, the refrigerant gas containing a large amount of lubricating oil in the crank chamber moves to the suction chamber by the first passage having an increased opening. For this reason, the amount of lubricating oil in the crank chamber becomes appropriate, the swash plate or the like does not agitate the lubricating oil so much, the lubricating oil hardly generates heat due to shear, and the viscosity of the lubricating oil does not easily decrease. For this reason, lubrication of a sliding part is performed suitably. Further, the refrigerant gas sucked from the suction chamber contains a large amount of lubricating oil, and the sliding portion between the cylinder bore and the piston is also preferably lubricated. At this time, the amount of lubricating oil in the refrigerant gas discharged to the refrigeration circuit outside the swash plate compressor increases, but there is no problem in the refrigeration capacity because the piston reciprocates at high speed.

  In addition, this swash plate type compressor increases the amount of lubricating oil in the crank chamber when the drive shaft is rotated at a low speed, but the swash plate only stirs the lubricating oil at a low speed, and the viscosity of the lubricating oil is not much. It does not decrease and the temperature of the lubricating oil hardly increases. For this reason, the lubrication of the sliding part is still preferably performed.

  Therefore, according to the swash plate compressor of the present invention, excellent sliding characteristics when the drive shaft is rotated at high speed and high refrigeration capacity when the drive shaft is rotated at low speed are realized. Is possible.

  The swash plate compressor of the present invention may be a fixed capacity type in which the inclination angle of the swash plate is not displaced, or may be a variable capacity type in which the inclination angle of the swash plate is displaced.

  In the swash plate compressor of the present invention, the escape passage only needs to communicate with the crank chamber to the suction chamber. In addition to the passage directly connecting the crank chamber to the suction chamber, the suction passage communicating with the suction chamber, etc. A passage that indirectly communicates the crank chamber with the suction chamber may be used. The escape passage is sufficient if it has the first passage, and may have another passage.

  The first passage communicates with one of the regions where the lubricating oil is high. The region where the lubricating oil is high and the region where the lubricating oil is low are determined by relative comparison with each other.

  Furthermore, the swash plate type compressor of the present invention may employ various types as long as it is an on-off valve that is displaced according to the number of rotations. For example, an on-off valve using a solenoid that detects the rotational speed by a rotational speed sensor or detects the centrifugal force by an acceleration sensor and electromagnetically displaces based on these signals can be employed. Further, a mechanical on-off valve in which the mass body is displaced by the centrifugal force and the valve body is actuated can be employed.

  The on-off valve may be provided in the first passage so as to be displaced by centrifugal force.

  In this case, the on-off valve can be displaced in the direction of increasing the opening degree of the first passage by increasing the centrifugal force, and can be displaced in the direction of decreasing the opening degree of the first passage by decreasing the centrifugal force.

  The escape passage has a second passage communicating with a region in the crank chamber where the lubricating oil is low, and the on-off valve can increase the proportion of the first passage in the escape passage by increasing the rotational speed of the drive shaft. ).

  In this case, the escape passage includes the first passage and the second passage, and the second passage can move the refrigerant gas that does not contain much lubricating oil in the crank chamber to the suction chamber. For this reason, it is easy to change the ratio of the 1st channel | path which occupies for a relief channel with an on-off valve, and the responsiveness with respect to rotation speed improves.

  In this swash plate compressor, when the drive shaft is rotated at a low speed, the on-off valve reduces the ratio of the first passage in the escape passage. For this reason, due to the first passage having a reduced proportion in the escape passage, the refrigerant gas containing a large amount of lubricating oil in the crank chamber does not move so much to the suction chamber, and the second passage does not contain much lubricating oil in the crank chamber. Move the refrigerant gas to the suction chamber. For this reason, the amount of lubricating oil in the refrigerant gas discharged to the refrigeration circuit outside the swash plate compressor is reduced, and a high refrigeration capacity is exhibited.

 Furthermore, this swash plate compressor reduces the amount of refrigerant flowing from the crank chamber to the suction chamber when the drive shaft is rotated at a low speed, thereby reducing the amount of refrigerant flowing from the crank chamber to the suction chamber. By reducing the amount of refrigerant gas circulated inside the machine, the amount of refrigerant gas used for the original purpose is increased, and the performance of the compressor is improved. In particular, in the case of a clutchless swash plate compressor in which power is always transmitted while the drive shaft of the swash plate compressor is operating, when the cooling is not required, the refrigerant gas is only circulated inside the compressor. However, when the drive shaft is rotated at a low speed, the refrigerant gas to be circulated can be minimized, and when the drive shaft is rotated at a high speed, excellent sliding characteristics are exhibited, and the drive shaft is It is possible to reduce the power of the compressor when rotating at a low speed.

  It is preferable that a throttle is formed in the second passage (claim 4).

  In this case, it becomes difficult to move the refrigerant gas that does not contain much lubricating oil in the crank chamber to the suction chamber, and the effect of the present invention by the lubricating oil becomes remarkable.

  In the swash plate compressor of the present invention, the swash plate can be supported so that the tilt angle can be varied. Further, a lug plate that receives a compression reaction force can be fixed to the drive shaft so as to be integrally rotatable. Furthermore, an oil guide path extending from the outer peripheral area of the crank chamber to the space between the housing and the lug plate can be formed in the housing. The first passage preferably communicates with the oil guide path (claim 5).

  According to the test results of the inventors, in the swash plate compressor, the outer peripheral area of the crank chamber is an area where there is a lot of lubricating oil, so that the lubricating oil can be easily guided to the first passage through the oil guide path. Is possible.

  A shaft seal device for sealing the drive shaft exposed from the housing may be provided between the housing and the drive shaft. The first passage preferably communicates with the oil guide path via the shaft seal device.

  In this case, a large amount of lubricating oil can be supplied to the shaft seal device to improve the durability of the rubber material of the shaft seal device.

  In the swash plate compressor of the present invention, the swash plate can be supported so that the tilt angle can be varied. Further, a lug plate that receives a compression reaction force can be fixed to the drive shaft so as to be integrally rotatable. Further, the first passage may have a guide hole formed in the lug plate and opened in the outer peripheral area of the crank chamber.

  According to the test results of the inventors, in the swash plate type compressor, since the outer peripheral area of the crank chamber is an area where there is a lot of lubricating oil, it is possible to easily guide the lubricating oil to the first passage through the guide hole. It is.

  In the swash plate compressor of the present invention, a shaft seal device for sealing the drive shaft exposed from the housing may be provided between the housing and the drive shaft. The second passage is preferably open to the crank chamber in the vicinity of the shaft seal device.

  In this case, lubricating oil can always be supplied to the shaft seal device, and the durability of the shaft seal device can be improved.

  Embodiments 1 and 2 embodying the present invention will be described below with reference to the drawings.

  The swash plate compressor of the first embodiment is of a variable capacity type used for air conditioning of vehicles. As shown in FIG. 1, the compressor includes a cylinder block 1, a front housing 3, and a rear housing 5. The cylinder block 1 has a cylinder bore 1 a extending in parallel with the axis of the drive shaft 7. A plurality are provided. In FIG. 1, the left side is the front of the compressor and the right side is the rear of the compressor.

  The rear housing 5 is formed with a suction chamber 11 and a discharge chamber 13 that communicate with each cylinder bore 1a via a valve unit 9. A crank chamber 15 is formed by the front housing 3 and the cylinder block 1, and shaft holes 3 a and 1 b are formed in the front housing 3 and the cylinder block 1. A shaft sealing device 17 is provided in the shaft hole 3a. A rubber material is used for the shaft seal device 17. A plain bearing 19 is provided in the shaft hole 1b. A storage chamber 1 c communicating with the shaft hole 1 b is formed at the center side of the rear end of the cylinder block 1, and the storage chamber 1 c faces the valve unit 9.

  The drive shaft 7 is rotatably supported by a shaft seal device 17 or the like with one end exposed from the front housing 3 and the center facing the crank chamber 15. A pulley or an electromagnetic clutch (not shown) is connected to the drive shaft 7, and the drive shaft 7 is driven to rotate by a drive source such as an engine via a belt wound around the pulley or the electromagnetic clutch. Further, pistons 21 are accommodated in the respective cylinder bores 1a so as to be able to reciprocate. Each piston 21 forms a compression chamber in the cylinder bore 1a.

  In the crank chamber 15, a lug plate 23 that receives a compression reaction force is fixed to the drive shaft 7, and a thrust bearing 25 and a plain bearing 27 are provided between the lug plate 23 and the front housing 3. Further, a swash plate 29 that can change an inclination angle formed with a virtual plane perpendicular to the axis of the drive shaft 7 is inserted into the drive shaft 7. The lug plate 23 is formed with a hinge portion 23a toward the swash plate 29. The swash plate 29 is provided with a hinge portion 29a toward the lug plate 23, and the hinge mechanism 23a, 29a constitutes a link mechanism 31. Yes. A pressing spring 33 is provided between the lug plate 23 and the swash plate 29 to urge the two in a direction away from each other.

  Further, a pair of shoes 35 are provided between the swash plate 29 and each piston 21 in the front-rear direction. The front shoe 35 is provided between the front surface of the swash plate 29 and the front seat surface of the piston 21, and the rear shoe 35 is provided between the rear surface of the swash plate 29 and the rear seat surface of the piston 21. It has been. Each shoe 35 has a substantially hemispherical shape. Each shoe 35 is a motion conversion mechanism.

  The drive shaft 7 has a first hole 37 extending in the radial direction, an outflow hole 39 communicating with the first hole 37, extending coaxially with the axis in the axial direction and extending to the rear end of the drive shaft 7, and an outflow hole 39. And a valve hole 41 extending in the radial direction is formed.

  As shown in FIG. 2, the first hole 37 is formed between the lug plate 23 and the front housing 3 by the radius of the drive shaft 7 from the axis of the drive shaft 7 to the outer periphery. The front housing 3 is formed with an oil guide groove 3 b that extends from the outer peripheral region of the crank chamber 15 to between the front housing 3 and the lug plate 23 and faces the thrust bearing 25. The front housing 3 is formed with an oil guide hole 3 c that communicates with the oil guide groove 3 b and faces the plain bearing 27 and the shaft seal device 17. The oil guide hole 3c communicates with the first hole 37 by facing the shaft seal device 17 through the shaft hole 3a. The oil guide groove 3b and the oil guide hole 3c are oil guide paths.

  As shown in FIG. 1, the rear end of the drive shaft 7 projects into the storage chamber 1 c, and the rear end of the outflow hole 39 is closed by a plug member 43. A valve hole 41 is formed slightly in front of the plug member 43. As shown in FIGS. 3 and 4, the valve hole 41 extends through the drive shaft 7, and allows the outflow hole 39 to communicate with the storage chamber 1 c.

  An open / close valve 45 is provided around the valve hole 41. The on-off valve 45 includes a spherical valve body 47 that can be seated in one opening 41 a of the valve hole 41, and a case 49 that is fixed to the drive shaft 7 around the valve hole 41. The valve body 47 also serves as a mass body. The case 49 has a valve chamber 49a on the opening 41a side. In the valve chamber 49a, a first spring 51 having a biasing force for biasing the valve body 47 in a direction away from the opening 41a and a second spring having a biasing force for biasing the valve body 47 in a direction approaching the opening 41a. 53 is provided. The valve chamber 49 a communicates with the storage chamber 1 c through a communication port 49 b formed in the case 49.

  As shown in FIG. 1, the valve unit 9 is provided with a throttle hole 9 a that communicates the storage chamber 1 c with the suction chamber 11. The cylinder block 1 and the valve unit 9 are formed with a second hole 55 that communicates the inner peripheral area of the crank chamber 15, that is, the portion close to the drive shaft 7 and the suction chamber 11. A throttle 55 a is formed in the valve unit 9 of the second hole 55. The oil guide groove 3b, the oil guide hole 3c, the first hole 37, the outflow hole 39, the valve hole 41, the communication port 49b, the storage chamber 1c, the throttle hole 9a, and the second hole 55 are escape passages. The oil guide groove 3b, the oil guide hole 3c, the first hole 37, the outflow hole 39, the valve hole 41, the communication port 49b, the storage chamber 1c, and the throttle hole 9a are the first passages. The second hole 55 is a second passage. The opening cross-sectional areas of the communication port 49b and the throttle hole 9a are set to be larger than the opening cross-sectional area of the opening 41a of the valve hole 41.

  A capacity control valve 57 is accommodated in the rear housing 5. The capacity control valve 57 communicates with the suction chamber 11 through the detection passage 59 and communicates the discharge chamber 13 with the crank chamber 15 through the air supply passage 61. The capacity control valve 57 detects the pressure in the suction chamber 11 to change the opening of the air supply passage 61 and change the discharge capacity of the compressor.

  A pipe 63 is connected to the discharge chamber 13, and the pipe 63 is connected to the suction chamber 11 through a check valve 65, a condenser 67, an expansion valve 69 and an evaporator 71. The compressor, the check valve 65, the condenser 67, the expansion valve 69, the evaporator 71, and the pipe 63 constitute a refrigeration circuit. A refrigerant gas mixed with lubricating oil is enclosed in the refrigeration circuit.

  In the compressor configured as described above, the capacity control valve 57 adjusts the pressure in the crank chamber 15 based on the pressure in the suction chamber 11 and the flow rate of the refrigerant gas, and changes the angle of the swash plate 29 with respect to the drive shaft 7. Thus, the discharge capacity is changed.

  Further, in this compressor, when the drive shaft 7 is rotated at a high speed such as while the vehicle is traveling at a high speed, the on-off valve 45 has a large centrifugal force and a valve body 47 as shown in FIG. The urging force of the first spring 51 moves away from the axis of the drive shaft 7 against the urging force of the second spring 53, and the valve body 47 increases the opening of the opening 41a.

  For this reason, the opening degree which the valve hole 41 leads to the communication port 49b becomes large, and the opening degree which the 1st hole 37 shown in FIG. 2 leads to the communication port 49b becomes large. At this time, the second hole 55 allows the crank chamber 15 and the suction chamber 11 to communicate with each other with a constant cross-sectional area. For this reason, as shown in FIG. 5, the throttle area which connects the crank chamber 15 and the suction chamber 11 is large. That is, the ratio of the first hole 37 occupying the escape passage is increased by the single on-off valve 45, and the ratio of the second hole 55 occupying the escape passage is decreased.

  The outer peripheral area of the crank chamber 15 shown in FIG. 2 is an area where there is a lot of lubricating oil, and the lubricating oil is guided from there to the first hole 37 by the oil guide groove 3b and the oil guide hole 3c. At this time, since the lubricating oil is guided to the first hole 37 through the shaft sealing device 17, a large amount of lubricating oil is supplied to the shaft sealing device 17, and the durability of the rubber material of the shaft sealing device 17 is improved.

  The refrigerant gas containing a large amount of lubricating oil in the crank chamber 15 reaches the storage chamber 1c through the outflow hole 39, the valve hole 41, and the communication port 49b by the first hole 37 having an increased proportion in the escape passage. Furthermore, it moves to the suction chamber 11 through the throttle hole 9a. For this reason, the amount of lubricating oil in the crank chamber 15 becomes appropriate, the swash plate 29 and the like do not agitate the lubricating oil so much, the lubricating oil hardly generates heat due to shear, and the viscosity of the lubricating oil does not easily decrease. For this reason, lubrication of sliding parts, such as between the swash plate 29 and each shoe 35, is performed suitably. Further, the refrigerant gas sucked from the suction chamber 11 contains a large amount of lubricating oil, and the lubrication of the sliding portion between the cylinder bore 1a and the piston 21 is also suitably performed. This demonstrates excellent durability at high speeds.

  At this time, the amount of lubricating oil in the refrigerant gas discharged to the refrigeration circuit outside the compressor increases. However, since the piston 21 reciprocates at high speed, there is no problem in the refrigeration capacity.

  When the drive shaft 7 is rotated at a low speed, such as when the vehicle is traveling at a low speed, the on-off valve 45 has a small centrifugal force as shown in FIG. The valve element 47 reduces the opening of the opening 41a by resisting the urging force of the second spring 53 and approaching the axis of the drive shaft 7 by bending to the urging force of the second spring 53. When the drive shaft 7 is rotated at a lower speed, the valve body 47 is seated in the opening 41a and closes the valve hole 41.

  For this reason, the opening degree which the valve hole 41 leads to the communication port 49b becomes small, and the opening degree which the 1st hole 37 shown in FIG. 2 leads to the communication port 49b becomes small. Also at this time, the second hole 55 allows the crank chamber 15 and the suction chamber 11 to communicate with each other with a constant cross-sectional area. For this reason, as shown in FIG. 5, the throttle area which connects the crank chamber 15 and the suction chamber 11 becomes small. That is, the ratio of the first hole 37 occupying the escape passage is reduced by the single on-off valve 45, and the ratio of the second hole 55 occupying the escape passage is increased.

  The inner peripheral region of the crank chamber 15 shown in FIG. 2, that is, the portion close to the drive shaft 7 is a region where there is little lubricating oil, and the refrigerant gas that does not contain much lubricating oil is introduced into the second hole 55 from there.

  Then, due to the second hole 55 occupying a larger proportion in the escape passage, the refrigerant gas not containing much lubricating oil in the crank chamber 15 moves to the suction chamber 11 through the throttle 55a. For this reason, the amount of lubricating oil in the refrigerant gas discharged to the refrigeration circuit outside the compressor is reduced, and high refrigeration capacity is exhibited.

  Furthermore, in this swash plate compressor, when the drive shaft 7 is rotated at a low speed, the first hole 37 is closed. Therefore, by reducing the total opening cross-sectional area of the escape passage, the amount of refrigerant gas moving from the crank chamber 15 to the suction chamber 11 is reduced, and the amount of refrigerant gas circulated inside the swash plate compressor is reduced. This increases the amount of refrigerant gas used for the original purpose and improves the performance of the swash plate compressor.

  At this time, the amount of lubricating oil in the crank chamber 15 increases, but the swash plate 29 and the like merely agitate the lubricating oil at a low speed, the temperature of the lubricating oil hardly increases, and the viscosity of the lubricating oil is greatly reduced. Absent. For this reason, the lubrication of the sliding part is still preferably performed.

  Therefore, according to this compressor, it is possible to achieve excellent sliding characteristics when the drive shaft 7 is rotated at a high speed and high refrigeration capacity when the drive shaft 7 is rotated at a low speed. Is possible.

  In the swash plate compressor according to the second embodiment, as shown in FIG. 6, a plurality of cylinder bores 2 a extending in parallel with the axis of the drive shaft 8 are penetrated through the cylinder block 2. The rear housing 6 is formed with a suction chamber 12 and a discharge chamber 14 that communicate with the cylinder bores 2a via a valve unit 10. A crank chamber 16 is formed by the front housing 4 and the cylinder block 2, and shaft holes 4 a and 2 b are formed in the front housing 4 and the cylinder block 2. A shaft sealing device 18 and a plain bearing 20 are provided in the shaft hole 4a. A rubber material is used for the shaft seal device 18. A plain bearing 22 is provided in the shaft hole 2b. A storage chamber 2 c communicating with the shaft hole 2 b is formed at the center side of the rear end of the cylinder block 2, and the storage chamber 2 c faces the valve unit 10.

  The drive shaft 8 is rotatably supported by a shaft seal device 18 or the like with one end exposed from the front housing 4 and the center facing the crank chamber 16. Further, pistons 24 are accommodated in the respective cylinder bores 2a so as to be able to reciprocate, and the respective pistons 24 form compression chambers in the cylinder bores 2a.

  In the crank chamber 16, a lug plate 26 that receives a compression reaction force is fixed to the drive shaft 8, and a thrust bearing 28 is provided between the lug plate 26 and the front housing 4. A swash plate 30 is inserted into the drive shaft 8 so that the tilt angle can be changed. A link mechanism 32 is formed between the lug plate 26 and the swash plate 30. Further, pressure springs 34 and 36 are provided between the lug plate 26 and the swash plate 30 and between the swash plate 30 and the drive shaft 8. A pair of shoes 38 are provided between the swash plate 30 and each piston 24 in the front-rear direction.

  The drive shaft 8 includes a main body 8a whose rear end is formed in a cylindrical shape, and a tubular body 8b which is inserted from the rear end of the main body 8a and is fixed in the main body 8a. A first hole 40 extending in the axial direction is formed between the main body 8a and the tube body 8b. In the lug plate 26, a guide hole 26a having a step formed in the middle is formed at a right angle to the axis. The guide hole 26 a communicates with the first hole 40 at the inner end, and communicates with the outer peripheral region of the crank chamber 16 at the outer end. In the lug plate 26, a valve chamber 26b is formed in the middle of the guide hole 26a, and an open / close valve 42 is provided in the valve chamber 26b. The on-off valve 42 includes a valve body 42a that can be seated in the opening on the inner end side of the guide hole 26a, and a spring 42b that biases the valve body 42a in the seating direction. The valve body 42a also serves as a mass body. A cylindrical cover body 26c is press-fitted into the guide hole 26a outside the valve chamber 26b and supports one end of the spring 42b.

  The main body 8a of the drive shaft 8 is formed with a second hole 44 extending in the radial direction and a communication hole 46 communicating with the second hole 44 and extending coaxially with the axis in the axial direction. The tube body 8 b has an outflow hole 48 that communicates with the communication hole 46 and extends to the rear end of the drive shaft 8. The second hole 44 is formed between the shaft seal device 18 and the plain bearing 20 by the radius of the drive shaft 8 from the axis of the drive shaft 8 to the outer periphery. In the front housing 4, an oil guide hole 4 b is formed between the front housing 4 and the lug plate 26 so as to open to the inner peripheral region of the crank chamber 16. The oil guide hole 4b faces the shaft seal device 18 through the shaft hole 4a and communicates with the second hole 44. The rear end of the drive shaft 8 protrudes into the storage chamber 2c.

  The valve unit 10 is provided with a throttle hole 10 a that communicates the storage chamber 2 c with the suction chamber 12. The guide hole 26a, the valve chamber 26b, the first hole 40, the oil guide hole 4b, the second hole 44, the communication hole 46, the outflow hole 48, the storage chamber 2c, and the throttle hole 10a are escape passages. The guide hole 26a, the valve chamber 26b, the first hole 40, the storage chamber 2c, and the throttle hole 10a are the first passage. The oil guide hole 4b, the second hole 44, the communication hole 46, the outflow hole 48, the storage chamber 2c, and the throttle hole 10a are the second passages. Other configurations are the same as those of the first embodiment.

  In this compressor, when the drive shaft 8 is rotated at a high speed such as when the vehicle is traveling at a high speed, the on-off valve 42 is driven against the biasing force of the spring 42b by the large centrifugal force of the valve element 42a. The valve element 42a increases the opening of the guide hole 26a away from the axis of the shaft 8. At this time, the second hole 44 allows the crank chamber 16 and the suction chamber 12 to communicate with each other with a constant cross-sectional area. For this reason, the throttle area for communicating the crank chamber 16 and the suction chamber 12 is large. For this reason, the ratio of the 1st hole 40 which occupies for an escape passage becomes large by the single on-off valve 42, and the ratio of the 2nd hole 44 for an escape passage becomes small.

  When the drive shaft 8 is rotated at a low speed, for example, while the vehicle is traveling at a low speed, the on-off valve 42 causes the valve body 42a to resist the small centrifugal force by the biasing force of the spring 42b. Approaching the shaft center, the valve element 42a reduces the opening of the guide hole 26a. When the drive shaft 8 is rotated at a lower speed, the valve body 42a is seated in the guide hole 26a. Also at this time, the second hole 44 allows the crank chamber 16 and the suction chamber 12 to communicate with each other with a constant cross-sectional area. For this reason, the throttle area for communicating the crank chamber 16 and the suction chamber 12 is reduced. For this reason, the ratio of the 1st hole 40 which occupies for a relief passage by the single on-off valve 42 becomes small, and the ratio of the 2nd hole 44 which occupies for a relief passage becomes large.

  Therefore, this compressor can achieve the same effects as those of the first embodiment. However, in this compressor, the oil guide hole 4b communicates with the inner peripheral region of the crank chamber 16, and only a small amount of lubricating oil is supplied to the oil guide hole 4b when the compressor rotates at high speed. The compressor of Example 1 is superior in terms of durability of the rubber material of the shaft seal device 18 at the time of high rotation. However, it is possible to always supply lubricating oil to the shaft seal device 18.

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

  For example, as shown in FIG. 7, in the compressor of the first embodiment, the throttle 55 as the second passage is deleted, and the outflow hole 39 and the storage chamber 1c are communicated with each other in the drive shaft 7, and have the same diameter as the throttle 55a. The diaphragm 55b can be formed as a second passage.

  If comprised in this way, while forming a 2nd channel | path easily, it can always supply lubricating oil to the shaft seal apparatus 18, and there can exist the same effect as Example 2. FIG. In this case, the opening sectional area of the throttle hole 9b is set to be equal to or larger than the sum of the opening sectional area of the opening 41a of the valve hole 41 and the opening sectional area of the diaphragm 55b.

  Further, as shown in FIG. 8, it is possible to eliminate the throttle 55 as the second passage and provide a groove 55 c that bypasses the valve element 47 in the opening 41 a of the valve hole 41 as the second passage. Even if it comprises in this way, there can exist the same effect.

  Further, in the compressor of the second embodiment, it is preferable that the opening on the outer end side of the guide hole 26a is the front in the rotation direction of the lug plate 26 so that the lubricating oil in the crank chamber 16 can be easily taken into the guide hole 26a.

  Further, in the compressors of the first and second embodiments, when radial bearings using rollers are employed instead of the plain bearings 19 and 22, the first passage and the first passage occupying the escape passage are defined as escape passages between the rollers. The ratio of the two passages may be changed. The link mechanisms 31 and 32 are not limited to those in the above-described embodiments, and various types can be adopted.

  The present invention is applicable to a vehicle air conditioner.

1 is a cross-sectional view of a swash plate compressor according to Embodiment 1. FIG. FIG. 3 is a cross-sectional view of the main part of the swash plate compressor according to the first embodiment. FIG. 3 is an enlarged cross-sectional view of a main part of the swash plate compressor according to the first embodiment while the drive shaft rotates at a low speed. FIG. 3 is an enlarged cross-sectional view of a main part of the swash plate compressor according to the first embodiment while the drive shaft rotates at a high speed. 6 is a graph showing the relationship between the rotational speed of the drive shaft and the throttle area in the swash plate compressor of Example 1. 3 is a cross-sectional view of a swash plate compressor according to Embodiment 2. FIG. It is sectional drawing of the swash plate type compressor of a modification. It is sectional drawing of the swash plate type compressor of another modification.

Explanation of symbols

1a, 2a ... cylinder bore 11, 12 ... suction chamber 13, 14 ... discharge chamber 15, 16 ... crank chamber 1, 2, 3, 4, 5, 6 ... housing (1, 2 ... cylinder block, 3, 4 ... front housing 5, 6 ... Rear housing)
7, 8 ... Drive shaft 29, 30 ... Swash plate 21, 24 ... Piston 35, 38 ... Motion conversion mechanism (shoe)
3b, 3c, 37, 39, 41, 49b, 1c, 9a, 55, 26a, 26b, 40, 4b, 44, 46, 48, 2c, 10a ... relief passage (3b ... first passage (oil guide groove), 3c ... 1st passage (oil guide hole), 37 ... 1st passage (1st hole), 39 ... 1st passage (outflow hole), 41 ... 1st passage (valve hole), 49b ... 1st passage (communication port) ), 1c, first passage (storage chamber), 9a, first passage (throttle hole), 55, second passage (second hole), 26a, first passage (guide hole), 26b, first passage (valve) Chamber), 40 ... first passage (first hole), 4b ... second passage (oil guide hole), 44 ... second passage (second hole), 46 ... second passage (communication hole), 48 ... second Passage (outflow hole), 2c... First passage and second passage (storage chamber), 10a... First passage and second passage (throttle hole)
45, 42 ... On-off valve 23, 26 ... Lug plate 3b, 3c ... Oil guide path (3b ... Oil guide groove, 3c ... Oil guide hole)
17, 18 ... Shaft seal device

Claims (8)

A housing having a cylinder bore, a suction chamber, a discharge chamber, and a crank chamber; a drive shaft rotatably supported by the housing and facing the crank chamber; and a swash plate supported by the drive shaft in the crank chamber; A piston housed in a cylinder bore so as to be capable of reciprocating; a motion conversion mechanism provided between the swash plate and the piston, wherein the oscillating motion of the swash plate is converted into reciprocating motion of the piston; and the crank chamber A swash plate type compressor having a relief passage for communicating with the suction chamber,
The escape passage has a first passage communicating with a region where the lubricating oil in the crank chamber is large,
A swash plate compressor comprising an on-off valve that increases the opening of the first passage by increasing the rotational speed of the drive shaft.   The swash plate compressor according to claim 1, wherein the on-off valve is provided in the first passage so as to be displaced by centrifugal force. The escape passage has a second passage that communicates with a region where the lubricating oil in the crank chamber is low,
The swash plate compressor according to claim 2, wherein the on-off valve increases the proportion of the first passage in the escape passage by increasing the rotational speed of the drive shaft.   The swash plate compressor according to claim 3, wherein a throttle is formed in the second passage. The swash plate is supported so that the tilt angle can be changed,
A lug plate that receives a compression reaction force is fixed to the drive shaft so as to be integrally rotatable,
An oil guide path extending from the outer peripheral area of the crank chamber to the space between the housing and the lug plate is formed in the housing,
The swash plate compressor according to claim 3 or 4, wherein the first passage communicates with the oil guide path. Between the housing and the drive shaft, a shaft seal device for sealing the drive shaft exposed from the housing is provided,
The swash plate compressor according to claim 5, wherein the first passage communicates with the oil guide path through the shaft seal device. The swash plate is supported so that the tilt angle can be changed,
A lug plate that receives a compression reaction force is fixed to the drive shaft so as to be integrally rotatable,
5. The swash plate compressor according to claim 3, wherein the first passage has a guide hole formed in the lug plate and opening in an outer peripheral region of the crank chamber.   A shaft seal device that seals the drive shaft exposed from the housing is provided between the housing and the drive shaft, and the second passage opens to the crank chamber in the vicinity of the shaft seal device. The swash plate compressor according to claim 7.

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