Pilot operated pressure valve

Abstract

A pilot operated pressure valve which limits the rate of pressure rise and substantially eliminates excessive system pressure spikes, the valve including an inlet, a hollow cylindrical main body sealingly connected at one end thereof to the inlet, a pilot chamber having a sleeve slidably mounted within the main body and an operating pressure adjustment connected to another end of the main body adjacent another end of the pilot chamber for varying the operating pressure of the valve. A main chamber receives pressurized fluid metered through a main orifice and discharges pressurized fluid through a damping orifice when the main chamber is filled and fluid inlet pressure exceeds a preselected inlet pressure level sufficient to open a spring biased pilot ball downstream of the damping orifice. The inlet will open an exit port upstream of the main orifice for discharging pressurized fluid from the valve back to a supply tank when inlet pressure exceeds the operating pressure. Pressurized fluid is also metered from the pilot chamber through a control orifice into a loading chamber to automatically further vary the operating pressure of the valve by including a relief valve for discharging pressurized fluid from said pilot chamber when fluid pressure exceeds the operating pressure.