Dean W May, Age 679449 Mcdaniel Rd, Terre Haute, IN 47802

4461315, Jul 24, 1984

Dec 15, 1982

6/449885

Dean W. May - Terre Haute IN

J. I. Case Company - Racine WI

F16K 1700

137255

A pressure protection system including a valve for isolating an auxiliary fluid circuit from a main fluid circuit when a leak occurs in the auxiliary fluid circuit. A valve is connected between a governor controlled compressor and the main fluid circuit and a pressure protection valve is connected between the compressor and an auxiliary fluid circuit. If a leak develops in the auxiliary fluid circuit, the pressure protection valve closes which permits most of the output from the compressor to be used to recharge the main fluid circuit. The pressure protection valve includes a supply passage and a delivery passage disposed substantially perpendicular to the supply passage. A plunger member is movable within the delivery passage for closing the supply passage when there is insufficient fluid pressure in the auxiliary fluid circuit. The pressure protection valve also includes a bypass orifice that permits a small amount of fluid to flow from the supply passage to the delivery passage when the supply passage is closed. If a leak develops in the auxiliary fluid circuit, the main fluid circuit does not lose pressure due to the leak because of the valve in the main fluid circuit.