Slant plate type compressor with variable displacement mechanism and method of controlling the capacity thereof

Abstract From the Canadian patent

In a slant plate type compressor with a variable displacement mechanism the stroke of the piston changes in response to the change of the slant angle. The relative distance of the piston from the valve plate when in top dead center position varies within a certain range in response to the change of the stroke of the piston. A detecting device disposes adjacent the cylinder detects the top dead center position of the piston in the compression space. The piston's stroke length is related to the detected top dead center position and once the piston's stroke length, is known this information can be used to determine whether capacity control is required.