Hydraulically trippable check valve

摘要

The body (1) of the hydraulically trippable check valve for mine support hydraulics according to the invention contains: a valve poppet (13) biased in the closing direction by a spring (22); a control piston (17) which can be acted on by a hydraulic control pressure, causing the poppet (13) to be lifted off its seat (11); and an initial relief valve (20, 21) which can be tripped by the control piston (17) against its spring closing force. Matters are arranged so that the control piston (17) which can be acted on by the hydraulic control pressure is dimensioned in terms of piston surface area (17') so that the poppet (13) of the check valve cannot be lifted off its seat (11) until the opening of the initial relief valve has caused a predetermined initial relief of operating pressure on the high-pressure side. Harmful oscillation or chatter of the valve poppet (13) of the check valve and/or control piston (17) are prevented by providing a restrictor in a transverse bore (26).