Variable displacement swash-plate compressor

Abstract

A compressor includes an actuator that is configured to change the inclination angle of a swash plate. A movable body, which is part of the actuator, has a primary acting portion and a secondary acting portion. The swash plate has a primary receiving portion and a secondary receiving portion. When the inclination angle of the swash plate is maximized, the primary acting portion contacts the primary receiving portion to push the swash plate. When the inclination angle of the swash plate is minimized, the secondary acting portion contacts the secondary receiving portion to push the swash plate.

1 . A variable displacement swash-plate compressor comprising:
 a housing, in which a swash plate chamber and a cylinder bore are defined;   a drive shaft rotationally supported by the housing;   a swash plate rotational in the swash plate chamber by rotation of the drive shaft;   a link mechanism arranged between the drive shaft and the swash plate, wherein the link mechanism allows change of an inclination angle of the swash plate with respect to a direction perpendicular to an axis of the drive shaft;   a piston reciprocally received in the cylinder bore;   a conversion mechanism, which causes the piston to reciprocate in the cylinder bore by a stroke corresponding to the inclination angle of the swash plate through rotation of the swash plate;   an actuator configured to change the inclination angle of the swash plate; and   a control mechanism, which controls the actuator,   
       wherein
 the link mechanism includes
 a lug member, which is located in the swash plate chamber and is fixed to the drive shaft, and 
 a transmitting member, which transmits rotation of the lug member to the swash plate, 
 
 the actuator includes
 the lug member, 
 a movable body, which is rotational integrally with the swash plate, wherein the movable body is configured to change the inclination angle of the swash plate by moving along the axis of the drive shaft, and 
 a control pressure chamber, which is defined by the lug member and the movable body, wherein the movable body is moved by changing a pressure in the control pressure chamber, 
 
 the movable body has a primary acting portion and a secondary acting portion, which are configured to push the swash plate with the pressure in the control pressure chamber, 
 the swash plate has a primary receiving portion and a secondary receiving portion, which are pushed by the primary acting portion and the secondary acting portion, 
 a top dead center associated part for positioning the piston at a top dead center and a bottom dead center associated part for positioning the piston at the bottom dead center are defined on the swash plate, 
 the primary acting portion is configured to contact the primary receiving portion to push the swash plate when the inclination angle of the swash plate is maximized, 
 the secondary acting portion is configured to contact the secondary receiving portion to push the swash plate when the inclination angle of the swash plate is minimized, and 
 the secondary acting portion is located between the primary acting portion and the bottom dead center associated part. 
 
     
     
         2 . The variable displacement swash-plate compressor according to  claim 1 , wherein
 an inclination range in which the inclination angle of the swash plate changes includes a first inclination range, which includes the maximum inclination angle, and a second inclination range, which includes the minimum inclination angle,   in the first inclination range, the primary acting portion contacts the primary receiving portion, and the secondary acting portion is separated from the secondary receiving portion, and   in the second inclination range, the primary acting portion is separated from the primary receiving portion, and the secondary acting portion contacts the secondary receiving portion.   
     
     
         3 . The variable displacement swash-plate compressor according to  claim 2 , wherein the primary acting portion is located between the axis of the drive shaft and the top dead center associated part. 
     
     
         4 . The variable displacement swash-plate compressor according to  claim 2 , wherein the secondary acting portion is located between the axis of the drive shaft and the bottom dead center associated part. 
     
     
         5 . The variable displacement swash-plate compressor according to  claim 2 , wherein
 a discharge chamber is defined in the housing,   a check valve is located between the discharge chamber and an external condenser,   when a differential pressure of the discharge chamber relative to the condenser is greater than or equal to a predetermined value, the check valve is switched to an open state,   when the differential pressure of the discharge chamber relative to the condenser is less than the predetermined value, the check valve is switched to a closed state to prevent refrigerant gas from flowing back from the condenser to the discharge chamber, and   a boundary between the second inclination range and the first inclination range is defined in accordance with time at which the check valve is switched from the closed state to the open state as the inclination angle of the swash plate is increased from the minimum inclination angle.   
     
     
         6 . The variable displacement swash-plate compressor according to  claim 1 , wherein
 the primary acting portion is one of a first-side primary acting portion and a second-side primary acting portion, which form a pair, wherein the first-side primary acting portion and the second-side primary acting portion are arranged on opposite sides of a bottom dead center plane, which includes the bottom dead center associated part and the axis of the drive shaft,   the primary receiving portion is one of a first-side primary receiving portion, which corresponds to the first-side primary acting portion, and a second-side primary receiving portion, which corresponds to the second-side primary acting portion,   the secondary acting portion is one of a first-side secondary acting portion and a second-side secondary acting portion, which form a pair, wherein the first-side secondary acting portion and the second-side secondary acting portion are arranged on opposite sides of the bottom dead center plane, and   the secondary receiving portion is one of a first-side secondary receiving portion, which corresponds to the first-side secondary acting portion, and a second-side secondary receiving portion, which corresponds to the second-side secondary acting portion.   
     
     
         7 . The variable displacement swash-plate compressor according to  claim 1 , wherein
 the swash plate has a weight, which is located between the axis of the drive shaft and the bottom dead center associated part and projects toward the movable body, and   the secondary receiving portion is located on the weight.