Patent GB-200946-A (GB)
Title: Improvements in door-locks and the like
IPC: E05B37/00
Filed: 1922-04-29
Abstract: 200,946. Cappellari, A., and Donzelli, L. April 29, 1922. Locks, permutation; keyholes, obstructing.-The bolt of a key-operated lock can only be operated when permutation elements are set correctly, attempts to withdraw the bolt with the elements incorrectly set resulting in a slight movement of the bolt which is then held against movement in either direction and causing the key to be retained in the keyhole. The bolt 42 is operated by the key 43 by releasing the usual tumblers. A double-hook-headed member 31 is carried by the bolt and when the discs 11, 24 are not correctly set, an attempt to withdraw the bolt results in the engagement of the hook with the sharp edges of a washer 20 pressed upwardly by a spring 19 and of a block 27 pressed downwardly by a spring 30, these sharp edges and the edge 41 of the circular recess 39 in the block 27 preventing movement of the bolt in either direction. In this condition, it is impossible to release the bolt from the outside without breaking the lock. From the inside it is released by a screw which passes through a hole in the casing 18 and engages a threaded hole in the washer 20 and pushes up the block, releasing the hook. By leaving the screw in this position the permutation device is rendered inoperative. For rendering it possible to operate the bolt without using the screw, the washer 20 is provided with a radial block 5 extending into a radial slot 14 in a boss 13 at the end of a spindle 1, which is held in rotatably adjustable connection with the setting disc 11 by the teeth 23 on the back of the disc and similar teeth on a disc 10 which can slide but not turn in relation to the spindle 1. The block 27 can slide, but not turn, in an open ended box 6 which is rigid with the serrated disc 8 and column 3 enclosing the column 2 fixed to the disc 11. The disc 8 is in rotatably adjustable connection with a serrated disc 9, which can slide in relation to a cylinder 4 carried by the second setting disc 24, which is held against turning therein by lugs 38 engaging slots in the cylinder. The under surface of the block 27 is provided with a circular recess 39 bounded by a sharp edged flange 40 and a flange 41, and this recess is interrupted by a radial groove 29, Fig. 5, bounded by sharp edges 39<1>, 39<11>. When the disc 11 is turned to the correct position, the polygonal projection 15 on the spindle turns the washer 20 to bring the block 5 in alignment with the lower hook of the head 31 and when the disc 24 is correctly set, the radial slot 29 is in alignment with the upper hook of the head. When the key is turned to withdraw the bolt, the hook head 31 pushes apart the members 27, 20 against their springs 30, 19, and is not held by the sharp edges 40. 21 against further movement since the groove 29 interrupts the edge 40 and the block 5 keeps it out of engagement with the edge 21. In the form shown in Fig. 8, the bolt has a projection 31 with one hook only which engages the edge 21 of the washer 20 unless the washer is set to align a radial block similar to the block 5 with the hook. In this construction, the keyhole is provided in a cylinder of adjustable length to allow for the thickness of the door, and the cylinder is turned to operate the cog 44 through intermediate gearing. The cog 44 turns a star wheel 54, between a pair of teeth of which is engaged a spring arm 55 fixed to the block 13 which has a radial slot 14 to allow entry of the hook 31. The block 13, turned by the star wheel, turns the washer 20 and has a spindle 56 carrying a nut 321 on the outside, said nut carrying a sleeve 57. To disengage the hook 31 from the washer 20 from the inside, the sleeve 57 is turned, moving the block 13 and washer bodily towards the casing 59, axial alignment being maintained by the shank 60 in a recess in the pivot 53 of the gear wheel. To change the combination, the sleeve is rotated till the spring 55 is disengaged from the star wheel.