Patent ID: 8464753

Claim:
A valve system for activating a piston of a piston-cylinder arrangement, the piston being configured to activate a movable contact piece of a high-voltage power switch, the valve system comprising: a pilot control valve including 3/2-way valve; and a main valve arrangement including a first main valve and a second main valve, wherein the first and second main valves include 2/2-way valves, wherein in a first position the pilot-control valve is configured to move the first main valve into an open position so as to direct a path for a high pressure fluid to a space above the piston, wherein in a second position the pilot-control valve is configured to connect the space to a low-pressure tank so as to relieve a pressure in the space above the piston via the second main valve, wherein the pilot-control valve is configured to open the second main valve and configured to close the first main valve, wherein the first and the second main valves each include a valve body, a slide, which is displaceably arranged within the valve body, and a plurality of control faces, wherein each control face comprises one or more annular surfaces, wherein a pressurized fluid is configured to be applied to the plurality of control faces, wherein the plurality of control faces include a first control face and a second control face acting on the slide in one direction and a third control face acting on the slide in another direction, such that a sum of a force from the first control face and a force from the second control face is equal to a force from the third control face, and wherein the first control face of the second main valve includes a first and a second end face and is connected to the low-pressure tank.