AUTOMATIC VOLUME RATIO VARIATION FOR A ROTARY SCREW COMPRESSOR

摘要

A valve for varying volume ratio in a screw compressor to balance a compression pocket pressure and a discharge pressure in the screw compressor comprises a valve body and a reed valve. The valve body defines a duct and an auxiliary port. The duct includes an open end in communication with a discharge chamber of the compressor and thereby the discharge pressure. The auxiliary port extends from a rotor bore of the compressor to the duct and provides fluid communication therebetween for communicating the compression pocket pressure to the duct. The reed valve is disposed within the duct for regulating fluid flow between the compression pocket and the duct. The reed valve is operable via a pressure differential between the compression pocket pressure and the discharge pressure.