Patent ID: 6875941

Claim:
A hydraulic operating apparatus for a switch, comprising: an operating piston connected to a movable contact element of a circuit breaker; a main control valve for controlling high-pressure hydraulic fluids acting on both surfaces of said operating piston to thereby switching said circuit breaker through said operating piston; and a pressure accumulator for exerting accumulated pressures on said high-pressure hydraulic fluids; wherein said pressure accumulator comprises a closing pressure accumulator and an interrupting pressure accumulator provided independently from each other, and said closing pressure accumulator and said interrupting pressure accumulator comprise a closing pressure accumulation chamber and an interrupting pressure accumulation chamber into which said high-pressure hydraulic fluids acting on both surfaces of said operating piston are introduced respectively, a closing pressure accumulation piston and an interrupting pressure accumulation piston disposed respectively in said closing pressure accumulation chamber and said interrupting pressure accumulation chamber, and a closing accumulated pressure exerting means and an interrupting accumulated pressure exerting means for exerting the accumulated pressures respectively on said high-pressure hydraulic fluids introduced into said closing pressure accumulation chamber and said interrupting pressure accumulation chamber through said closing pressure accumulation piston and said interrupting pressure accumulation piston.