GB620352A - Improvements in and relating to night and other latches or locking devices for doors - Google Patents

Abstract

620,352. Locks. WARING, D. A. W., PARRATT, A. R., STOKES, Ltd., A., and FARNHAM ENGINEERING WORKS, Ltd. Jan. 13, 1947, No. 1074. [Class 44] A lock of the type operable by a handle, on the inside and by a barrel lock on the outside has independent key and handle actuated followers each provided with a cam form which, upon rotation in the direction opposite to opening, provides a wedging obstruction to the bolt for deadlocking the bolt or retaining it in the retracted position. The key actuated follower 8, Fig. 2, has a lug 14 normally engaging the forward side of the bridge piece 5 on the slotted lath 3 for withdrawing the bolt. When the key is turned in a clockwise direction through 360 degrees to the position shown a cam 15 engages under the bridge piece 5. In the shot position of the bolt the bridge piece 5 lies to the right of the trunnion centre, so that rearward movement causes binding engagement between the bridge piece 5 and the follower. The lock follower is segmentally enlarged at 16 to allow the barrel lock to turn through a complete revolution so that the key may be withdrawn. The handle actuated follower 7, Fig. 4, has a similar cam portion 21 for deadlocking the bolt and a segment 17 with shoulders 18, 19 the former engaging the bridge piece for normal retraction and the latter for deadlocking. The bolt is retained retracted by forcing back the bolt as shown in Fig. 6 and turning the handle clockwise until the cam 21 engages under the bridge piece 5. Forward movement of the bolt now causes rotation of the follower and binding engagement with the bridge piece 5. Specification 578,397 is referred to.