Patent GB-869533-A (GB)
Title: An improved combination lock
IPC: E05B37/16
Filed: 1957-05-30
Abstract: 869,533. Combination locks. MARTI, A. S., MARTI, J. S., MARTI, J. S., and MARTI, M. S. May 30, 1957 [May 30, 1956], No. 17154/57. Class 44. A combination lock comprises a plurality of superimposed discs 46 each having a notch 48 and a toothed portion 47 on the circumferential edge, an axle 33 on which the discs are freely rotatably mounted, a plurality of toothed racks 41, one for each disc and each having a rack portion 43 on one edge engaged with the toothed portion of one of the discs and a toothed portion 42 on the opposite edge, a plurality of claws 24 one for each rack and each having a tooth 25 thereon engageable between the teeth of the toothed portion 42 of one of the racks and having a tail 26 spaced from the tooth, a slidable claw-carrying plate 15 on which the claws are pivotally mounted in superimposed position, a reciprocally mounted feeler button means 15 engageable with the carrying plate 15, pawl means 58 engageable with the racks for holding the racks after movement thereof by the feeler button means, the carrying plate and one of the claws, a selector axle 33 having a knob 3 on one end and having a plurality of eccentric portions 37 thereon spaced axially and angularly from each other, the selector axle extending through the space between the teeth and the tails on the claws with one eccentric portion corresponding to each tail, spring means 28 bearing against the claws urging the tails into contact with the axle, whereby when a tail engages an eccentric portion, the tooth on that claw is engaged with one of the racks, a pivotal arm 50 having a bar 53 thereon bearing against the peripheries of the discs, and a sliding plate means 73 engaged with the pivotal arm for preventing sliding movement of the plate means 73 in one position and permitting the sliding plate 73 to slide in a straight line when the arm is moved. The button 5 has a shaft 7 formed with an inclined portion 8 which acts on the plate 15 to displace it. For each position of the selector axle 33 one claw engages its corresponding rack so that upon actuation of the feeler button the respective disc is rotated. When all the notches 48 in the discs are aligned, the bar 53 is moved into the aligned notches. The portions 37 of the' axle 33 are arranged so that only one claw at a time can engage its respective rack. When the knob 3 has been rotated to its first position, depression of the feeler button 5 against the pressure of a spring 10 causes the inclined portion 8 of the shaft 7 to engage an inclined portion of a block 13 attached to the plate 15 and move the plate upwardly against a spring; the claw engaged with its corresponding rack then moves the rack upwardly to the extent of one tooth and when the feeler button is released the plate 15 moves downwardly carrying the claw with it so that the claw engages the next rack tooth; downward movement of the rack is prevented by the pawl means 58 which engages a section of pawl teeth 57. Thus a series of depressions of the feeler button is necessary to rotate the respective disc 46 to the position in which its notch 48 is aligned with the bar 53. When one disc has been aligned with the bar the selector knob 3 is further rotated so that the next claw engages its rack and the button is again depressed. The process is repeated until all the discs are in the position in which their notches are aligned. The bar 53 thenmoves into the notches and the consequent movement of the arm 50 moves the sliding plate 73 through a pin-and-slot connection 77, 76. The plate 73 carries a stop peg 62 and when the plate is moved by the arm 50, this peg moves out of the path of a lock bolt so that the lock bolt can be moved to its unlocking position. The movement of the plate 73 also rotates a pivoted lever 68 one end 71 of which engages a notch 72 in the plate. The rotation of the selector axle 33 is controlled so that the axle can only rotate in one direction by means of a ratchet wheel 36 which co-operates with a pawl 64; the ratchet wheel is provided with as many teeth as there are racks and it is also provided with a projection 67 which when the selector axle has been rotated through a complete revolution bears on one arm of the lever 68 when this lever has been moved by the sliding of the plate 73. When it is desired to restore the lock into its locked condition the selector axle is rotated so that the projection 67 bears on the arm of the lever 68 and a tail portion 78 of the lever engages a rod 79 which disengages the pawls 58 from the racks; at the same time the end 71 on the lever 68 moves the plate 73 to its initial position and through the pin-and-slot connection the arm 50 is moved so that the bar 53 moves out of the notches in the discs; the discs and racks are then returned to their original positions. The discs are mounted on a plate 44 which is pivoted at one end on a pin 81; the plate 44 is provided with an opening 82 which can be engaged by the bit of a key after the key has been passed through a keyhole in the rear wall of the lock; when the key is turned the plate 44 disengages the discs 46 from the racks 41 provided that the discs are in their unlocking position with their notches aligned so that the bar 53 can move into the notches. The selector knob is then turned to move the pawl 58 to release the racks and the combination of the lock can then be changed. A push button and selector knob can be provided on both sides of the lock.