DRUCKMITTELBETAETIGTES DREIWEGEVENTIL ZUM UMSTEUERN HYDRAULISCHER MEDIEN

摘要

A three-way valve suitable for reversing a fluid actuating device such as the kind used for actuating an electrical switching apparatus includes a cylinder defining inlet and outlet passages as well as a space between these passages which is connectable with the actuating device. A drive piston is movable in the cylinder between respective end positions. The piston is configured as a differential piston and has one end-face portion facing the space intermediate the inlet and outlet passages; this end-face portion of the piston is configured as a valve body corresponding to one of the passages. A second valve body is provided and corresponds to the other passage. The second valve body is mounted on a valve rod which extends through the intermediate space and into the differential piston for coupling the valve bodies together. The differential piston engages the valve rod to hold the same so as to facilitate the movement of the rod within defined limits relative to the piston whereby a firm seating of the valve bodies on valve seats corresponding to respective ones of the valve passages is assured.