Fuel control valve

A pressure responsive control valve for a fuel system supplying fuel at a variable pressure to an internal combustion engine, said valve comprising:

• a housing having a cylindrical chamber therein and an inlet extending from one end of said cylindrical chamber to the variable pressure output of said fuel system, said housing means having a bypass outlet connected to a low pressure section of said fuel system;
• a cylindrical element having a conical elastomeric tip displaceable axially in said chamber from a first position in which the conical tip seats against said inlet to prevent flow through said chamber and a second position in which it permits flow therethrough, said valve element being urged toward said second position by the fuel pressure of said system, the area of said inlet being a given ratio less than the cross sectional area of said chamber taken in a plane at a right angle to the direction of travel of said valve element thereby permitting the area of the valve element exposed to fuel system pressure to vary from a first area when the valve element is in said first position to a second and substantially larger area when said valve is in said second position;
• a spring acting on said valve element;
• a plug threaded into the end of said housing and forming the end of said chamber opposite the inlet end, whereby said spring abuts said plug, said plug being rotatable to vary axial position of one end of said spring and thus vary the force it applies to said valve element, said plug having an elastomeric pad positioned in the threaded section thereof for restraining said plug in a selected position thereby varying the pressure at which fuel is bypassed;
• means defining a predetermined orifice removably interposed in said bypass outlet for providing a predetermined restriction to flow,
• whereby when the pressure in said fuel system exceeds a given first level said valve bypasses flow to reduce the pressure thereof, said valve requiring the fuel system pressure to drop to a second level below said first level before bypass flow is terminated and the output pressure of said fuel system is varied through a range of pressures intermediate said first and second levels.