Closure for a pressurized chamber

A door closure system for a pressurized chamber is provided. The door system includes a hinge affixed to the chamber housing which supports a transverse door beam of the door. An inner door plate is supported by a handwheel driven screw rotatably mounted to the door beam. As such, the door plate is displaceable between sealing, chamber opening confronting and open positions by the handwheel. A cam finger is provided on the door plate and the free end of the door beam is formed into latch hooks. A spring-biased swing latch is provided adjacent the chamber opening on the side of the chamber opposite the hinge means. The swing latch includes a latch bar and a recessed cam area. Accordingly, when the door plate is rotated into its confronting position and the handwheel is turned thereby advancing the door plate relative to the chamber opening, the cam finger is caused to ride in the recessed cam area of the swing latch. Such movement causes the swing latch to be rotated thereby causing the latch bar to engage and retain the latch hooks. Further rotation of the handwheel causes a sealing means on the door plate to sealingly engage the chamber opening.