GB734722A - Locks - Google Patents

Abstract

734,722. Locks; sliding bolts. PARKES & SONS, Ltd., J., and BUTTER, F. J. May 12, 1954 [May 28, 1953], No. 14846/53. Class 44. In a lock of the kind in which a dead bolt 12 is operated by a lever, the lever is mounted to rock about a fixed axis 23 and has two arms 13, 14 which co-operate respectively with inclined ramps 15, 16 on the bolt to effect full throw of the bolt, one in the bolt-shooting direction and the other in the bolt-withdrawing direction and at the end of the bolt-throwing action whichever arm has effected such action rides off the associated ramp and takes up a dead-centre position, or a position a little beyond dead-centre, in which it operates as a strut between an abutment 17 or 18 on the bolt and the lever pivot to retain the bolt against movement in the opposite direction until again actuated by the lever. As shown, the lever is adapted to be rocked from one side of the door by a handle (not shown) and is provided with an arm 24 by which the lever is rocked from the other side of the door by a thrower 28 carried by a cylinder lock 26. A pin 30 on the arm 24 co-operates with one arm of a spring located on a stump 32 to bias the lever to either of its extreme positions. In another arrangement, Fig. 2 (not shown), the arm 24 is engaged and rocked by an intermediate bellcrank member which is engaged by the thrower 28. In a further arrangement, the thrower 28 engages a slider which is adapted to rock the bolt lever, the runner being indexed in its extreme positions by one arm of a leaf spring mounted in the lock case. The slider may be secured by levers and the levers in the slider may be operated directly by the bit of a key.