Operating device for gas circuit breaker

An operating device for a gas circuit breaker, the operating device comprising:

• an operating cylinder having an exhaust port;
• and an operating piston having one end operatively connected to the gas circuit breaker for effecting a breaking operation and closing operation, said operating piston being received in said operating cylinder so as to reciprocably move between a first position and a second position, said operating piston dividing an internal space of said operating cylinder into a first chamber and a second chamber respectively disposed on opposite sides of said operating piston, said operating piston being movable from said first position to said second position at a time of the breaking operation of said operating device, said operating piston being movable from said second position to said first position at a time of the closing operation of said operating device, an exhaust port communicating with said first chamber when said operating piston is disposed near said second position, and said exhaust port communicating with said second chamber when said operating piston is remote from said second position;
• means for introducing high-pressure air into said first chamber at the time of said breaking operation;
• and
• exhaust valve means for discharging the air from said first chamber when the air pressure within said first chamber decreases below a predetermined level, said exhaust valve means including a valve element having a pressure-receiving portion which receives the air pressure from said first chamber, and wherein said pressure-receiving portion is positioned so that said pressure-receiving portion is out of contact with said operating piston when said operating piston is disposed at said first position.