GB456801A - Improvements in electric door locks - Google Patents

Abstract

456,801. Electrically - controlled locks. DAVEY, W. C., 176, Tottenham Court Road, London. Feb. 20, 1936, Nos. 5115 and 12638. [Class 44] To enable a lock tc be released from a distance the striking plate is pivoted anc normally held fast by locking-means releas able by a solenoid the locking means be ing engaged in its un locked position by a mechanical catch which is released by the closing of the door Mounted in an E- shaped casting 1 is a T-shaped plate 2 pivoted about pins 3 and normally retained in the position shown by a pin 6 passing through a solenoid 4 and engaging a recess in the plate. When the solenoid is excited the pin 6 is raised and its head is engaged by a pivoted catch 8 on a swinging member 9 which is retained in its normal position by springs 22. The bolt of the lock can then turn the plate 2 as the door is pushed but on reclosing the door the plate 2 is returned to its normal position, aided by spring-pressed balls 10 and the member 9 is swung laterally to permit the pin 6 to fall and re-engage the plate 2. In a modification the pivoted catch 8 is carried by an extension of the pivot of the striking plate 2 and turns therewith, a horizontal plate on the top of the striking plate preventing the pin from dropping further until the plate 2 occupies its normal position. Instead of locking the plate 2 directly, the pin 6 may actuate a pivoted catch 15, Fig. 10, which engages a projection on the plate 2. When the pin 6, which is loaded by a weight 20, is raised by the solenoid the catch 15 is raised by a spring and the door as it opens can then turn the plate 2 until one edge engages a recess in a pivoted spring-pressed lever 17. As the door closes the end of the lever 17 is struck to release the plate 2 which is returned by a volute spring 21 acting on the pivot extension which carries the pivoted detent 8.