Servo-controlled fluid valve - has bypass with throttle and relief arrangement to eliminate valve closing surge

摘要

The main operating element of the valve is a diaphragm performing opening and closing movements against a valve seat according the momentary pressure differential between valve inlet and pressure chamber. A pilot valve is operated by a solenoid and when in a closed position pressure between the chamber and valve inlet is equalised and the diaphragm stays closed. When the solenoid is energised the core of the solenoid is pulled back against spring force and fluid accumulated in the chamber via a hypass and the throttle starts to flow through the open pilot valve seat.