Patent ID: 6189563
Filing Date: 2001-02-20
Classification: F16K,Y10T

Abstract:
A fluid pressure relief valve, comprising:a valve body having bores forming inlet and outlet ports;a valve seat in the inlet port;an axially bored valve head on the body opposite the valve seat said valve head having a skirt projecting toward said valve seat;an axially bored piston valve slidably supported by the valve head for movement toward and away from the valve seat,said valve head having axially offset first and second fluid passageways respectively communicating with the outlet port and downstream limit of the valve head;a blind cylinder on said valve head having a wall forming a pressure chamber axially opposite the valve seat and having a third fluid passageway through the cylinder wall;a manifold having a valve chamber on the valve head providing fluid communication between the first, second and third fluid passages through the valve chamber;a pilot operated three-way two position control valve in the manifold valve chamber; and,fluid pressure sensing means responsive to the fluid pressure in the blind cylinder pressure chamber for normally maintaining the pressure differential across said piston valve equalized and shifting said control valve to exhaust fluid pressure downstream from the downstream limit of said piston valve in response to fluid pressure above a predetermined value.