Chamber door lock

Abstract

A chamber door lock for a roller lock system wherein a vertically reciprocable locking bar is provided with a series of rollers and a vertically reciprocable chamber door is provided with spaced block weldments. The chamber door lock includes a cam beam pivotably mounted on the chamber and coupled to the locking bar. Upward movement of the locking bar to its uppermost position clears the rollers from the door block weldments and swings the cam beam away from the top of the door to a clearance position whereby the chamber door can be raised and swung to an open position. Downward movement of the locking bar to its lowermost position moves the rollers into engagement with striker plates on the door block weldments thereby urging the door against the chamber face so as to compress the door gasket and seal the chamber face. Downward movement of the locking bar also swings the cam beam from the clearance position past an over-the-center position to a limit stop position wherein the cam beam is located at a slight clearance above the top of the door. Upward movement of the door then forces the cam beam against a stop so that any further movement of the door is obstructed by the cam beam.