GB205615A - Improvements in locks - Google Patents

Abstract

205,615. Morris, A. W. Aug. 8, 1922. Sliding latches; preventing operation of; lock mechanism, operated by non-rotating key.-A latch bolt is operated by a plate-like follower, through a slot in which pass locking pins, with waists, which can be set to allow movement of the follower, or which can block it against movement, preventing actuation of the latch bolt. The pins are brought to their inoperative or operative position by a flat non-rotating key on the outside and by a sliding plate forming part of the mechanism on the inside. The follower 23 is carried by the squared central part 22 of the handle spindle 20, and has a pair of pins engaging arms 38 of the yoke 39 through a central slot in which passes the T-head 43 of the shank of the latch, a spring 46 being fitted between a fixed abutment 48 and a shoulder 47 of the latch. Two fixed pins 33 secure the abutment 48 and also the end plates 31, 24 and the disc 30. A third fixed pin 34 works in a curved slot 35 in the follower. Three locking pins 53 pass through slots in the disc 30. The cover plate 31 and a plate 26 secured inside the end cap 24, serve as a key-guide when the key is inserted in a slot 25 in the cap. The pins are secured at their other end by a channel-shaped cap 60. The pins have a tang 54 at the end covered by the cap 60, a cut-away part 55 at the keyhole end, and, in the middle, flattened waists 56 which co-operate with enlarged parts 58 in an arcuate slot 57 in the follower. When the waists 56 of the locking pins are not in alignment with the slot 57, the follower 23 cannot be turned by the handles 21 to withdraw the latch. To turn them to the position for operating the latch, from the outside, a key 61 is thrust into the key-slot 25, when inclined parts 62 contact with the cut-away parts 55 to turn the pins to align their waists 56 with the slot in the follower, allowing it to be turned. To adjust the pins from the inside, a sliding plate 59 is provided below the cap 60. Slots 63<1> in this plate have inclined sides 64, 65. The sides 64 when pulled into contact with the tangs 54 of the pins position the waists for preventing operation of the follower, while when the plate is pushed to contact the sides 65 with the tangs, the pins are rotated into position for allowing operation of the follower. A keyhole-shaped slot 66 in the sliding plate co-operates with a piece 69 on a trigger 70 to prevent sliding of the plate 59 to position the pins for unlocking. Sleeves are provided on the handle spindle and fixed pins 33, 34, to prevent displacement of the discs. The nose 50 of the latch has a flat 49 working in a plate 52 to prevent rotation of the latch A projection 40 on the yoke 39 travels in a slot 41 in the disc 30 to guide the yoke.