Abstract: A hinge for use with a swinging door provided with an electric lock or other electrically operated device or component therein in which the hinge is provided with chases and hollow hinge barrels sheathing a tubular collar which also serves as a hinge pin and provides a continuous passageway through the hinge for electrical conductors in order to maintain a continuous circuit or circuits through the hinge regardless of the position of the door. Each hinge leaf includes a barrel integral therewith with the barrel and leaf being a one-piece casting. The barrels completely enclose the tubular collar which forms a hollow hinge pin and protects the electrical conductors from attack in the event the leaves and barrels are pried apart.

Abstract: A prison door locking mechanism particularly suitable for use with each of a pair of sliding prison doors laterally movable into stacking or overlapping position. The door locking mechanism includes a novel pivotally mounted locking dog having a latch engageable with a door-suspending carriage to lockably restrain carriage movement. The locking dog includes a projecting arm engaged by a rack bar coupled to the carriage to insure deadlock rotation of the locking dog to its locking position.