Variable displacement swash plate type compressor

Abstract

In the compressor of the present invention, guide surfaces are formed on a lug plate and guided surfaces are formed on swash plate arms. The guide surfaces and the guided surfaces are respectively in linear contact with one another at a first abutment position when an inclination angle is maximum and are in linear contact with one another at a second abutment position when the inclination angle is minimum. The guide surfaces are formed such that portions between the first abutment position and the second abutment position are convex toward the guided surfaces. In the compressor, a contact angle at the first abutment position can be made large, and a contact angle at the second abutment position can be made small.

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 that is rotatably supported by the housing;   a swash plate rotatable in the swash plate chamber by rotation of the drive shaft;   a link mechanism that is provided between the drive shaft and the swash plate and allows change of an inclination angle of the swash plate to a direction orthogonal to a drive shaft axis of the drive shaft;   a piston that is accommodated in the cylinder bore to be capable of reciprocating;   a conversion mechanism that causes the piston to reciprocate in the cylinder bore at a stroke corresponding to the inclination angle by rotation of the swash plate;   an actuator capable of changing the inclination angle; and   a control mechanism that controls the actuator,   wherein the link mechanism has a lug member that is provided on the drive shaft in the swash plate chamber and faces the swash plate, and a swash plate arm to which rotation of the drive shaft is transmitted from the lug member,   on the lug member, a guide surface that faces the swash plate arm is formed,   on the swash plate arm, a guided surface that abuts on and is guided by the guide surface is formed,   the actuator has the lug member, a movable body that is disposed between the lug member and the swash plate and is movable in a direction of the drive shaft axis, and a control pressure chamber that is provided between the lug member and the movable body and moves the movable body by an internal pressure, and   the guide surface is formed such that a portion thereof between a first abutment position, where the guided surface abuts on the guide surface when the inclination angle is maximum, and a second abutment position, where the guided surface abuts on the guide surface when the inclination angle is minimum, is convex toward the guided surface.   
     
     
         2 . The variable displacement swash plate type compressor according to  claim 1 ,
 wherein a top portion of the guide surface is offset to the first abutment position side from a middle of the first abutment position and the second abutment position.   
     
     
         3 . The variable displacement swash plate type compressor according to  claim 1 ,
 wherein a radius of curvature of the guided surface differs between the first abutment position and the second abutment position.