GB190604215A - Improvements relating to Latch Locks - Google Patents

Abstract

4215. Taylor, W. H. Feb. 20. Latches; locks, key; knobs, attaching. - Relates to a night-latch the bolt of which can be blocked from either side, the blocking-mechanism being adapted for key-operation from outside. The latch-bolt 3 is operated from inside by the handle 12 through the follower 4, which acts on the ends 7 of rods 5 connected to the bolt. At the back of the latch case 2, which is placed in an outer casing 1, is mounted a slide 18 operable from inside the door by a lever 29 and provided with a block 19 adapted to be brought behind one of the latch rods 5 for locking the latch in its extended position. The slide is retained in either position by a spring pin 20. On the outer cover (not shown) of the casing 2 are mounted a disk 22, provided with a cam 23, and the bell-crank lever 24. The disk 22 is adapted to be operated by a key, the escutcheon being provided with suitable locking-mechanism, and the cam 23 is arranged to act on the tail end 7 of the latch in order to withdraw the latch from the outside. The bellcrank 24 has one arm engaging a slot 27 in the slide 18, the other is cam-shaped and engages with a pin 26 on the cam 23. If the slide 18 has been moved from the inside to block the bolt, by means of a key inserted from the outside and turned in a counter-clockwise direction, the slide is first moved downwards by means of the pin 26 acting on the bell-crank 24, and then the bolt is withdrawn by the cam 23. To block the bolt from the outside, the key is turned in the reverse direction, so as to cause the pin 26 to come in contact with the shoulder 28 of the bell.crank. The bolt may be held in its withdrawn position, by causing the part 7 to engage with the slot 32 in the slide 18. In a modification, the slide is placed just behind the latch bolt 3, a projection being provided thereon to come behind a corresponding projection on the bolt, and is operated from inside by a knob and from outside as described above. The follower 4 is attached to a disk mounted in the front plate of the case 2 and provided with a transverse slot, into which projections on the boss of the knob take, the knob being mounted in the front plate of the outer casing 1.