Rotary piston refrigerant compressor for vehicle air conditioning - has inlet ports on inside of four epitrochoidal piston lobes

摘要

The compressor has a piston (3) mounted on a crank of a shaft in a cylinder (5). The piston has a pinion which engages an annular wheel to make the piston rotate on its own axis as it travels round the inside of the cylinder. The piston has four epitrochoidal lobes and the cylinder has five correspondingly shaped recesses. These form variable volume working spaces (12-16) as the piston revolves. Admission to the working spaces is through ports (19) in the piston lobes. Refrigerant enters these from a space (20) within the piston which it reaches through a passage (21) in the end of the piston. A valve disc (23) inside the piston attached to the crank regulates the opening of the ports.