Patent GB-1184442-A (GB)
Title: Combination Lock for Security Cabinets and the like
Inventor: MILLER HARRY C
IPC: E05B37/08
Filed: 1967-06-17
Abstract: 1,184,442. Combination padlocks. SARGENT & GREENLEAF, Inc. 17 June, 1967, No. 28049/67. Heading E2A. A combination padlock having a concealed shackle or bolt 41 for engaging in a staple 29 has a dial 19 associated with a driving cam 50 for positioning in known mnaner a number of co-axial tumbler wheels 47, 48, 49 and a fence lever 58, Fig. 4, carried by a turntable 45 so as to be movable around the peripheries of the tumbler wheels and acted upon by an over-centre spring 61 so as normally to assume either an outer inactive position as shown or, after the tumbler wheels and driving cam have been correctly set, an inner active position, Fig. 8, in which its base 60 enters aligned gates in the tumbler wheels and driving cam, a device being provided for impulsing the fence lever 58 from its inactive to active position. If, when the device is operated, the tumbler wheels are not correctly set, the spring 61 immediately returns the fence lever to its inactive position. The device may take the form of a shaft 74 which carries a cam 75, Fig. 8, and which is rotated through 360‹ by the operator to raise a slide 65 and then allow it to be snapped downwardly by a spring 68 so that its V-shaped end 71 engages an ear 76 of the fence lever 58. The ear 76 moves in a groove 77 in a base 24 and is cammed by the end surface 71a of the slide 65 outwardly when the lock is locked to move the fence lever to its inactive position. The turntable 45 carrying the fence lever 58 has an edge 54a, Fig. 4, which cooperates with an enlargement 39a, of the sliding bolt plate 39 to raise the bolt plate and bolt 41 when the turntable 45 (with the fence lever 58) is moved clockwise from the position shown in Fig. 8 to the locking position shown in Fig. 4. The bolt is lowered by the engagement of the ear 76 of the fence lever 58 with a projection of the bolt 39. The bolt 41 moves through an enlargement 43, Fig. 3, of the base 24, a recess 44 being provided for the staple 29. The base is formed with the post 38 on which tumbler wheels 47, 48 and 49 and the driving cam 50 are mounted, and is readily removable from a casing 13 carrying the dial 19, the latter having recesses for cooperation with projections 62 of the driving cam. The casing 13 and knob 19 have hardened steel linings 37 and 22 and the dial has cavities containing balls 21 to interfere with X-rays which might be used to study the lock. The casing 13 has flanges 33 for engagement in channels 32 of a support 30 carried by a file drawer, e.g., to be locked, the staple 29 being secured to the cabinet frame 26. In normal operation of the lock, a stud 34 mounted in the base 24 is held in engagement with an aperture 36 in the support 30 to prevent removal of the lock. Changing the combination. To change the combination, the tumblers are set to open the lock and the shaft 74 and cam 75 are given an extra 180‹ rotation, in addition to the usual 360‹, to leave the slide 65 in a raised position, Fig. 9. The turntable 45 can then be moved clockwise beyond the locking position to the position shown in Fig. 9, the ear 76 entering an extension 77c of the groove 77. In this position of the turntable, an offset foot 45b of it allows a spring to withdraw the stud 34 from interlocking engagement with the support 30, Fig. 3, secured to the drawer. The lock can then be removed to give access through the base 24 for a change-combination key by which the tumbler wheels 47, 48, 49 may be de-clutched from their hubs in known manner to permit re-setting. Scattering tumblers. The bolt plate 39 carries a hooked slide 80, Fig. 4, which by engaging serrations on the tumbler wheels is drawn downwardly against the action of a spring on locking, clockwise movement of the turntable 45, so that when the fence lever 58 disengages the tumbler wheels, the latter are suddenly moved counter-clockwise.