Patent GB-205824-A (GB)
Title: An improved lock for doors
IPC: E05B63/04
Filed: 1923-10-22
Abstract: 205,824. Moreaux Fils et Boyer. Oct. 21, 1922, [Convention date]. Locking sliding latches; latches, sliding; reversible latches; lock mechanism, lever type; bolts; keyholes, obstructing; keyhole escutcheons; striking plates.-- A lock having a spring-shot latch-bolt which can be locked by a tumbler or blocked either by a key-operated tumbler-controlled sliding blocking bolt from both sides of the door, or by a turn button operated by a knob from the inside and by a square key from the outside, is reversible for right and left hand doors, and has a plate for holding the blocking bolt out of action. This plate may be removed to another part of the casing if not required. The latch bolt has a head 37 with a groove 39 for housing the end of its spring 87 and for oiling, and a sheet metal tail 40 with a pair of lugs 41 to engage the follower arms 78, a projection 42, and a notch 50 for engagement by the clip 73 of the bolt tumbler 72, pivoted to the casing of 19. A gap 43 in the bolt tail enables the key to be turned. The bolt is retracted by turning the follower 76, the arms 78 of which are provided with detachable rollers or bushes 79,80 to reduce friction. In the position shown in Fig. 1, the lip 73 of the bolt tumbler 72 is resting on a lug 61 on the blocking bolt 52, which is in its retracted position. The bolt 37 can therefore be retracted by the follower. To lock the bolt in its shot position, the key is inserted into the keyhole 13 from either side of the door and turned, lifting levers 63 controlling the bolt 52 and shooting the bolt 52 forward so that its shoulder 55 blocks the latchbolt. This moves the lug 61 away from the lip 73 of the tumbler 72, which then drops into a notch 50 in the bolt and a notch 60 in the blocking bolt to further secure both. The blocking bolt may be used to withdraw the bolt 37 by means of a double turn of the key in the double talon 57, 58, the lug 59 engaging the lug 42 en the bolt. The latch bolt can be blocked, from the inside only, by the catch 86 pivoted at 81 and turned by an exterior knob. One arm of the bolt spring 87 engages flats to control the position of the catch. The bolt 52 may be prevented from being returned into its effective position by the key, by taking the plate 88 from the pin 21 and hanging it on the pin 20 where it is interposed between the end of the bolt 52 and the casing. Instead of the follower, a draw bar 46, Fig. 3, and knob 47 may be used to operate the bolt. The bolt and casing parts are symmetrical about a median horizontal plane, so that by moving the necessary parts such as levers, tumblers, &c., from one side of this plane to the other and inverting the lock, reversibility is rendered possible. The cover plate is provided with a key-pipe 34 having a slot 35 for the bit, and with an escutcheon having a keyhole cover pivoted thereto. The tumbler 72 comprises an arm carrying the bolt-engaging lip 73 and a part 70 to which is secured by a mortice and tenon for sliding adjustability, a key-bit engaging piece 71. The striking-plate, which is not reversible, comprises a securing flange 92, strenthening rib 93, and bevelled front plate with aperture 91 for the latch.