GB258757A - Improvements in sliding latches - Google Patents

Abstract

258,757. Laing, J. G. Dec. 10, 1925. Night latches of the type wherein locking and unlocking means are provided on the knob side of the latch as well as on the pin tumbler lock side, have a special key for operating such locking means. The latch-bolt b, normally shot by springs d and retracted by the followed f of the knob g and the follower i of the pin-tumbler lock, can be blocked by the arm q of a lever pivoted on the rod o when the arm t of the lever is rocked. The arm t has a cam face s engaged by the lock-follower i so that the follower can move the arm q out of the path of the bolt b against action of the spring q<1>. From the handle side of the latch, the arms q, t are operated by a rod y<2> carried by a barrel operated by a special key from the side of the lock casing. To retain the arm q in inoperative position against the action of its spring q<1>, the arm t snaps into a slot w in an arm v carried by a spring-pressed rod u as shown in Fig. 4. The rod u is depressed to release the arm t to block the bolt by pressure on the knob y<1> from the handle side of the latch, and by the arrangement of an arm x on the follower i with a hook u<1> on the arm v from the pin-tumbler side.