Patent ID: 7186096
Filing Date: 2007-03-06
Classification: F04B

Abstract:
1. A swash plate type variable displacement compressor connected to an external drive source for compressing refrigerant gas that contains lubricating oil comprising: a cylinder block defining a cylinder bore; a housing fixed to the cylinder block, the housing defining a crank chamber, a suction chamber and a discharge chamber; a drive shaft supported by the housing and the cylinder block for rotation, the drive shaft being driven by the external drive source, the drive shaft having an axis; a swash plate supported by the drive shaft in the crank chamber so as to rotate integrally with the drive shaft, the swash plate being inclinable with respect to the axis of the drive shaft, an inclination angle of the swash plate being varied in accordance with the pressure in the crank chamber; a piston accommodated in the cylinder bore so as to define a compression chamber in the cylinder bore, the piston being coupled to the swash plate, the rotation of the swash plate being converted into the reciprocating movement of the piston, displacement of the compressor being varied by the reciprocation of the piston in accordance with the inclination angle of the swash plate; a control mechanism for controlling pressure in the crank chamber, the control mechanism including a bleed passage that interconnects the crank chamber with the suction chamber for decreasing the pressure in the crank chamber; and a communication path for interconnecting the crank chamber with the compression chamber only while the inclination angle of the swash plate is substantially the maximum inclination angle and the piston is located substantially at its bottom dead center.