PRESSURE SHIFT VALVE AND ELECTRICAL BY-PASS

摘要

A hydraulic valve in which a pressure shift is caused between an inlet pressure (P0) and an outlet pressure (P1) by a piston (2) sliding within a bore (2a) counter to a spring (11), and supporting a valve (5, 7) which is opened by a needle (8) once the piston has travelled over a given distance. The needle is driven by a solenoid (9) and keeps the valve permanently open while the solenoid is not energised, in order to cancel out the differential pressure between the valve inlet and outlet when the valve is not operational.