Electrohydraulic flow medium control - uses torque and solenoid amplification and regulates mean discharge pressure by response of feedback circuit

摘要

An electro-hydraulic flow medium control valve, has a first amplification stage represented by a torque drive. It can adjust the position of the valve plug relative to two nozzles. There is a second amplification stage represented by a solenoid valve. It has very good response characteristics and a high resolution capacity. The coil responds to the control pressure of the flow medium to regulate the mean discharge pressure of the valve. The mean flow pressure operates the feedback circuit. The feedback responds to the mean pressure of the flow medium at the outlet of the valve to change the position of the valve plug in such a way that the setting of the plug by the torque drive is counteracted.