Patent GB-1313396-A (GB)
Title: Combination lock
IPC: E05B37/08
Filed: 1970-04-16
Abstract: 1313396 Locks MOSLER SAFE CO 16 April 1970 18285/70 Heading E2A A combination lock comprises a set of tumbler sliders 84 each of which is settable in a predetermined position in order to withdraw a bolt 21 and is biassed towards engagement with a corresponding one of a set of cam followers 88 for movement therewith, the cam followers being biassed against the slide bias towards engagement with respective cams 79, a movable pin 100 engageable with the sliders to prevent their movement and ratchet 106 and pawl means for advancing the pin to accumulatively engage the sliders. Setting the combination is by rotation of a dial on a shaft 33 which turns a cam shaft 59 and the cams 79 through balls 57 movable in grooves 56 in a driver 36 secured to the shaft 33 allowing axial and rotary movement of the shaft. As the cams rotate one end of the pivoted cam followers 88 follows the periphery of the respective cam while the other end moves the respective slider 84 laterally on two posts 94. Springs 89 urge the cam followers towards the cams and springs 95 urge the sliders in engagement with the cam followers. Pushing in the shaft 33 sets each slider, by pivoting a plate 50 connected to the driver 36 this being possible only at integer dial positions in which one of the notches on the driver flange 39 aligns with a stud 45 on a housing. An indexing pawl 112 on the plate 50 engages in the first notch of a ratchet 106 and moves it one step and a holding pawl 113 drops into the second notch of the ratchet. The plate 50 is returned to its original position by two biasing springs. The pin 100 projecting from a bracket 105 secured to the ratchet 106 is inserted in one of a plurality of holes 98 in the first slider 84 and retains the slider stationary with a tooth on the end of the slider aligned with a gate 97 in one of a series of fences 85 supported by a pin 132 passing through a slot therein. When all the numbers of the combination have been dialled, resulting in the slider having its tooth 96 aligned with the gate 97 of the corresponding fence 85, each slider being held by the pin 100 on the ratchet 106 which is moved one step each time a number is dialled and the shaft 33 pushed in, a surface of the bracket moves from beneath a leg 157 of a lever 155 which is pivotally connected to the bolt 21 and the lever moves downwardly urged by a spring 159. This movement imparts downward movement to the fences 85 by engagement of the tip of fence pin 132 in a lever slot 161, and the lever nose 158 drops onto the periphery of a cam 72 on the shaft 59. Dial 23 is then turned to a fixed zero position in which the nose 158 engages a notch 73 in the cam thereby connecting the cam with the lever 155 and the bolt 21. Further rotation of the dial withdraws the bolt. The bolt is projected by opposite rotation of the dial. Location of the nose with the edge of the slot lifts the nose from the slot and raises the fences away from the sliders, raising the lever. The dial 23 with the shaft 33 is pulled out and the plate 50 moves the pawl 112 to engage release member 121 and the pawl is thereby swung from the ratchet. Camming surface 128 on the plate disengages the holding pawl 113 from the ratchet. The ratchet then moves to its original position under the bias of a spring 110 raising the leg 157 onto the bracket surface and the pin 100 disengages the sliders and the springs 95 restore the sliders into engagement with the respective cam followers. To change the combination, the combination is first set and the bolt is withdrawn, the head of a fence shaft 137 is then accessible through an aperture 151 in the lock cover. The shaft is rotated to free the fence members for individual movement and a spring 138 shifts the shaft so that the fence pin 132 disengages the lever slot 161. The bolt is then extended, the fences remain engaged with the sliders, the new combination is then set, the bolt is withdrawn, the shaft 137 is rotated to clamp the fences in their new positions and the bolt is extended.