Patent GB-614292-A (GB)
Title: Improvements relating to combination lock
IPC: E05B37/00
Filed: 1946-07-11
Abstract: 614,292. Permutation locks. YOUNG, E. M. July 11, 1946, No. 20774. Convention date, July 11, 1945. [Class 44] A permutation lock of the kind in which a rotatably and axially movable member is moved progressively in response to rotary movements according to a pre-arranged code to release a latch, bolt, &c., comprises a bank of discs rotatable in a casing and axially movable therein, cam surfaces arranged on and inclined to the discs, and fixed abutment means engageable by the cam surfaces on rotation of the discs alternately in opposite directions to move the bank of discs from a normal to an operative position in which locking means are engaged to release the latch, &c. The lock comprises a cylindrical casing 5, Fig. 1, in the end wall 8 of which is journalled the stem 10 of a bearing 11 through which the squared end of the main spindle 12 extends, carrying a control knob 13. A plate 14 with an index mark, fixed to the spindle and rotating in an opening in a fixed dial plate 15 enables the predetermined rotary movements to be effected. A drum 18 is mounted to slide on the spindle, but constrained to rotate therewith by a pin 22 working in a slot in the spindle. The inner end of the spindle rotates in the wall of the latch casing 27. A spring 30 urges the drum 18 towards the knob 13. The inner part of the spindle is bored to house a rod 23 which carries a knob 31 and is secured to the drum 18 by pin 22. Mounted on the drum 18 is a bank of discs 33, Fig. 7, the drum having longitudinal grooves within which engage lugs 38 projecting inwardly into the central apertures of the discs; thus enabling the discs to be set on the drum in accordance with any pre-arranged code. Spacing washers are located between each disc. 'Except for the inner and outer discs, 33a, Fig. 6, and 33b, Fig. 8, respectively, each disc is formed with peripheral slots 39 having inclined vanes 40, 40a, the former being idle, while the latter, directed to the opposite side of the disc, coact with fixed screws 43, 44 in the casing to advance the drum progressively towards the latch, on rotation alternately in opposite directions, each time to the extent determined by the setting of the operative vanes 40a of the discs. The arrangement is shown diagrammatically in Fig. 5, in which one screw 43 is shown in the position occupied relatively to the discs between successive rotations. When the drum has been advanced to the full extent, a roller 54 on a disc 21 fixed to the end of the drum engages a flange 55 on the latch to withdraw it on further rotation. Each of the discs is also provided with a pair of open slots 47, Fig. 7, the slots on each disc being aligned with one another, and also, in the normal position of the drum and spindle, with the screws 43, 44. On release of the knob 13, the spindle is rotated to normal position by means of a spring 48, Fig. 1, and, the open slots 47 being then in line with the screws 43, 44, the drum is returned to the position of Fig. 1 by the spring 30. The latch can be operated from within by pulling out and turning the knob 31, thus advancing the drum to its opening position and withdrawing the latch. Provision may be made to lock the spindle by means of a plunger engaging a slot therein.