A Study on Capacity Control of a Vane Type Rotary Compressor for Automotive Air Conditioners

Abstract

Since a compressor used for an automotive air conditioner is driven by an engine, refrigerating capacity will change according to the speed of the engine. While wobble plate compressors achieve continuous capacity control by changing the slope of the wobble plate, rotary compressors can perform only a few stage capacity control by opening or closing bypass ports. We developed a rotary compressor with a continuous capacity control mechanism which is activated by rotating a bypass port in a front plate, and evaluated its performance. The experimental compressor showed a high coefficient of performance under operating conditions which simulated practical conditions of automotive air conditioners, though its performance slightly decreased due to the re-expansion loss with the increase of the rotating angle of the bypass port.