Hydraulic operated valve

摘要

An hydraulic device for selectively providing a secondary pressure at a first or second port (31, 32) in accordance with the movement of an operating member (35) by means of first and second push rods (22, 22') disposed between the operating member (35) and respective first and second spool valves (28, 28'), which extend into first and second spring chambers (26, 26'), wherein first and second pistons (29, 29') fixed respectively to said first and second push rod (22, 22') in piston chambers (50, 50') form first and second damping chambers (24, 24') which communicate respectively with said first and second spring chambers via first and second check valves (25b, 25b') and form first and second oil chambers (24a, 24a') which communicate respectively with said first and second damping chambers via first and second throttles (25a, 25a').