摘要 |
An improved solenoid actuated valve is provided of the type having a fluid pressure-operated diaphragm to move a valve head between open and closed positions. Fluid under pressure at a valve inlet is admitted through a diaphragm port to a control chamber for normally retaining the diaphragm and a valve head carried thereby in the closed position. A solenoid unit is actuatable to vent the control chamber to relieve pressure therein, whereby the fluid pressure at the valve inlet displaces the diaphragm to open the valve head. The opened valve head moves into close proximity with a flow control piston within the control chamber and cooperates therewith to meter fluid outflow from the control chamber in a manner maintaining a minimal or substantially zero pressure differential across the diaphragm. The position of the flow control piston is adjustable to variably select the open position of the valve head in accordance with a desired valve flow rate. Improved filters for the diaphragm port and for the solenoid unit are also disclosed.
|