Individual hydraulic prop with filling/drawing valve and pressure fluid return

摘要

For use in underground individual prop support, an individual prop valve is provided whose case integrates a return valve for setting, a non- return valve for drawing, and a pressure-limiting valve for securing the prop against overload. The valve case of the pressure- limiting valve is moved hydraulically if the case is also equipped on the drawing side with a coupling piece which has a gripping groove and locking shoulder. A push bolt which is loaded correspondingly by the pressure fluid acts on the valve case and moves it by a predefined length, so that the non-return valve is hereby opened and the pressure fluid is able to flow from the prop interior through the suction pump connection located on the setting side. Here the channels or spaces are proportioned in such a way that an increased amount of pressure fluid may be discharged, whereby this process is supported by a pump connected to the suction pump connection.