Variable displacement swash plate type compressor

Abstract

In the compressor of the present invention, first and second recessed strip portions are recessed in a second supporting member. First and second annular members are respectively provided in the first and second recessed strip portions. The first and second annular members respectively include joint gap formed by first to third cutouts. The third cutouts function as aperture in the first and second annular members. The first and second annular members respectively move in the first and second recessed strip portions according to a pressure difference between a pressure regulation chamber and a swash plate chamber. Consequently, the compressor adjusts a flow rate of a refrigerant circulating from the pressure regulation chamber to the swash plate chamber and adjusts a supply amount of lubricant supplied to a second sliding bearing and the like.

1 . A variable displacement swash plate type compressor comprising:
 a housing in which a suction chamber, a discharge chamber, a swash plate chamber, and a cylinder bore are formed;   a drive shaft rotatably supported by the housing;   a swash plate rotatable in the swash plate chamber by rotation of the drive shaft;   a link mechanism provided between the drive shaft and the swash plate and configured to allow a change in an inclination angle of the swash plate with respect to a direction orthogonal to a rotational axis of the drive shaft;   a piston accommodated to be reciprocatingly movable in the cylinder bore;   a conversion mechanism configured to reciprocatingly move the piston in the cylinder bore at a stroke corresponding to the inclination angle according to the rotation of the swash plate;   an actuator capable of changing the inclination angle; and   a control mechanism configured to control the actuator, wherein   the swash plate chamber communicates with the suction chamber,   the actuator includes:
 a fixed body fixed to the drive shaft in the swash chamber; 
 a movable body movable in the rotational axis direction in the swash plate chamber; and 
 a control pressure chamber defined by the fixed body and the movable body and configured to introduce a refrigerant including lubricant in the discharge chamber to thereby move the movable body, 
   in the housing, a pressure regulation chamber that communicates with the discharge chamber and the control pressure chamber and a shaft hole that allows the swash plate chamber and the pressure regulation chamber to communicate with each other are formed,   in the shaft hole, a bearing rotatably supporting the drive shaft is arranged,   a communication path that allows the pressure regulation chamber and the swash plate chamber to communicate with each other via the bearing is provided between the drive shaft and the shaft hole,   in the communication path, an annular member arranged around the drive shaft is provided,   the annular member includes an aperture that allows the pressure regulation chamber and the swash plate chamber to always communicate with each other, and   the annular member moves in the communication path on a basis of a pressure difference between the pressure regulation chamber and the swash plate chamber to thereby adjust a flow rate of the refrigerant circulating through the communication path.   
     
     
         2 . The variable displacement swash plate type compressor according to  claim 1 , wherein
 the communication path includes a recessed strip portion formed between the drive shaft and the shaft hole, and   the annular member is arranged in the recessed strip portion.   
     
     
         3 . The variable displacement swash plate type compressor according to  claim 1 , wherein
 the annular member includes a first cutout extending in an axial direction parallel to the rotational axis, a second cutout extending in the axial direction in an extending direction of the first cutout while shifting with respect to the first cutout in a circumferential direction orthogonal to the axial direction, and a third cutout extending in the circumferential direction to connect the first cutout and the second cutout, and   the third cutout is the aperture.   
     
     
         4 . The variable displacement swash plate type compressor according to  claim 1 , wherein
 the bearing is a radial bearing provided between the drive shaft and the shaft hole,   the annular member and the radial bearing are provided around the drive shaft and arranged between the pressure regulation chamber and the swash plate chamber, and   the radial bearing is arranged further on the pressure regulation chamber side than the annular member.   
     
     
         5 . The variable displacement swash plate type compressor according to  claim 4 , wherein
 an outer diameter of the annular member is substantially the same as an outer diameter or an inner diameter of the radial bearing.   
     
     
         6 . The variable displacement swash plate type compressor according to  claim 4 , wherein
 an inner diameter of the annular member is substantially the same as an outer diameter or an inner diameter of the radial bearing.   
     
     
         7 . The variable displacement swash plate type compressor according to  claim 1 , wherein
 the bearing is a radial bearing provided between the drive shaft and the shaft hole,   the annular member and the radial bearing are provided around the drive shaft and arranged between the pressure regulation chamber and the swash plate chamber, and   the annular member is arranged further on the pressure regulation chamber side than the radial bearing.   
     
     
         8 . The variable displacement swash plate type compressor according to  claim 7 , wherein
 an outer diameter of the annular member is substantially the same as an outer diameter or an inner diameter of the radial bearing.   
     
     
         9 . The variable displacement swash plate type compressor according to  claim 1 , wherein
 a plurality of the annular members are provided.   
     
     
         10 . The variable displacement swash plate type compressor according to  claim 2 , wherein
 the drive shaft includes a drive shaft main body and a cap fit in the drive shaft main body, the recessed strip portion being recessed in the cap.