GB1196945A - Improvements in and relating to Locking Door Handles - Google Patents

Abstract

1,196,945. Locks; latches. W. BARDFELD. 17 July, 1967, No. 32732/67. Heading E2A. A cylinder lock has its plug 2 fixed and its cylinder body 3 rotatable, when an appropriate key is inserted into the plug, to operate a latch or other member. Since the key serves only to unlock the cylinder body, it can be of relatively weak material such as plastics. The lock is fitted into a door-knob 8 controlling a sliding latch bolt 4. The knob 8 is secured to the cylinder body 3 and has an inwardlyprojecting flange 9 which engages in an annular space between plates 11 and 12 secured to the door by screws 15, only accessible in certain positions of the cylinder body 3. The plug 2 is keyed at 17 to the plate 11 and retained by a ring 34. A pin I projecting from the body 3 moves in arcuate slots 37, 38, 24 in the plates 11, 12 and in the case 23 of the latch bolt 4 and enters a slot in the latter. When the knob 8 is unlocked, the bolt 4 is free to be moved either outwardly by a spring or inwardly by the knob. The knob can however be locked with the bolt in either its withdrawn position or its fastening position. In the first case, the bolt is held inoperative and in the second case, it is not possible to withdraw the bolt by means of the knob. The bolt 4, however, may have recesses (28, 29), Fig. 2 (not shown), engageable by a further bolt to retain it in either its operative or its withdrawn position.