Variable displacement compressor

A variable displacement compressor comprising:

• a housing, wherein the housing includes a cylinder bore;
• a single-headed piston accommodated in the cylinder bore;
• a drive shaft rotatably supported by the housing;
• a rotor supported by the drive shaft, wherein the rotor rotates integrally with the drive shaft;
• a drive plate supported by the drive shaft, wherein the drive plate slides along and inclines with respect to the drive shaft;
• and
• a hinge mechanism located between the rotor and the drive plate, wherein rotation of the drive shaft is converted into reciprocation of the piston via the rotor, the hinge mechanism, and the drive plate, wherein the hinge mechanism guides the drive plate such that the drive plate slides along and inclines with respect to the drive shaft, and wherein the inclination angle of the drive plate determines the displacement of the compressor,
• wherein the hinge mechanism includes a cam, which is located on one of the rotor and the drive plate, and a guide portion, which is located on the other one of the rotor and the drive plate, wherein the cam has a cam surface, which has a predetermined profile, and the guide portion abuts against the cam surface, wherein one of the cam surface and the guide portion slides against the other in accordance with inclination of the drive plate, and the guide portion traces a path corresponding to the profile of the cam surface with respect to the cam, and
• wherein the path includes a first path corresponding to a small displacement region of the compressor and a second path corresponding to a large displacement region of the compressor, wherein the profile of the cam surface is determined such that the first path and the second path bulge in a direction opposite to each other to compensate for fluctuation of a top dead center position of the piston with respect to the housing.