Patent GB-189543-A (GB)
Title: Improvements in permutation locks
IPC: E05B37/00
Filed: 1921-09-01
Abstract: 189,543. Bella, F., di. Sept. 1, 1921. Locks, permutation; bolts; staples for locks.- A lock has a hollow springless bolt inside which is yieldingly attached a core connected to the operating means, so that normally the core can operate the bolt but can move independently to avoid breakage when the bolt is blocked by a permutation mechanism. The box staple also has a sliding plate to allow the door to be opened when the bolt is shot, and a spring catch holds back the plate, and is released by the bolt when the door is shut with the bolt shot, to allow the plate to slide forward to lock the bolt. The casing 1 has a sleeve 4 extending through the door, inside which is a sleeve 15 carrying a dial 12 fitted with a milled part 11 for turning. The sleeve 15 has legs 16, Fig. 11, interfitting with legs 17 on a member carrying a fixed disc 19, this member forming a continuous sleeve with the sleeve 15 and carrying thereon two rotatable discs 20, 21. These discs are rotatably held in their correct position by a pair of guide-pieces 22, Fig. 12, secured to the casing by screws 23, 28, passing through holes 24, 29 respectively, and between these guide-pieces is a vertically sliding blocking- piece 55, Fig. 10, fitted in a guide 58, Fig. 14, both of these being recessed at 57, 60 respectively. The bolt 33 is hollow and houses a core 37 which is yieldingly connected to the bolt by spring- pressed balls 40 as shown in Fig. 13. The bolt has a slotted arm 42 which, with a screw 45 in the casing, serves as a guide, and an arm 43 for co-operating with the blocking-piece 55. This arm has a lug 46 working in a slot 47 also forming guiding means. The bolt-operating spindle 9 passes through the sleeve 15 and has a knob 1( fitting in a recess in the part 11. The inside end of the spindle has holes through which a pin 5' may pass to connect the flanged disc follower 48 by means of its neck 52. A screw 54 may pass through an eye in the pin 51 into a threaded hole in the disc 48 to secure the pin. The end of the spindle fits into a projecting part 8 on the casing A ring 49 to which the core is pivoted fits over the follower disc 48. The knob 11 is turned tc align various numbers on the dial 12 with a mark on the plate 13, so setting the discs 19, 20, 21 by interconnection of their screws 32. These screws may be put in various holes 31 to vary the combination. When the discs are set, theii notches 30 are aligned and are situated above the blocking-piece 55, which then rises under the action of its spring 56 to bring its recess 57 intc line with the recesses 60 of the fixed piece 58. If the knob 10 is now turned, the core pulls back the bolt 33, the arm 43 thereon passing through the recess 57. If the knob 10 is turned without setting the discs, the bolt cannot move, but the core can move independently of the bolt, thereby avoiding breakage of the lock. A bridge-piece 35 has a hole 35<1> corresponding to a hole 41 in the bolt, so that even when the combination is set. the bolt can be locked from the inside by means of a pin 61 passing through the holes 35<1>, 41. The box staple 65 of the lock retains the bolt by means of a sliding plate 67 which can be moved aside to release the door from the inside without withdrawing the bolt. The staple has an arm 68 which is bent over to form a tongue 69 carrying a spring-pin 75 and forming a neck within which is a fixed headed rod 71. The sliding plate 67 has a lug 73 sliding along the rod 71 and normally holding the plate 67 in its closed position by a spring 72. An operating lug 74 enables the plate 67 to be slid back to release the bolt, and the plate 67 can be retained in either of its positions by the spring pin 75 engaging holes 78, 79. To secure the door from the outside when the bolt is shut, the plate 67 is pushed back just sufficiently to be held retracted bv an L-shaped spring-catch 82. When the pin 75 is in the hole 78, the end of the plate 67 just covers the end of the L-shaped catch to hold it out of its operative position. When the catch holds back the plate as in Fig. 7, on shutting the door with the bolt shot, the bolt presses back the catch 82, releasing the plate 67, which is then shot forward over the bolt to lock it, by the spring 72.