US Patent 7270311 Pendulum gate valve

A pendulum gate valve includes a housing defining a valve chamber, the valve housing having a vacuum-chamber opening in a front wall and an access opening in a rear wall aligned with the vacuum-chamber opening and defining a through-hole extending from one side of the valve housing to the other side for providing access to the vacuum chamber, a carriage assembly pivotally mounted within the valve housing and moveable between a open position remote from the openings and a closed position between the openings, a valve plate reciprocally mounted on one side of the carriage assembly and movable between an unsealed position spaced from the vacuum-chamber opening and a sealed position sealing the vacuum-chamber opening, a valve-plate actuator carried on the carriage assembly for moving the valve gate between the unsealed and sealed positions, a retractable support reciprocally mounted on another side of the carriage assembly movable between a retracted position spaced from the access opening and an extended position engaging the valve housing adjacent the access opening, and a retractable-support actuator carried on the carriage assembly for moving the valve support between the retracted and support positions. Preferably, the valve-plate and retractable-support actuators are fluid actuators. A method of using the pendulum gate valve is also disclosed.