GB608097A - Improvements in and relating to locks - Google Patents

Abstract

608,097. Revolving-barrel locks. TRIGGS, W. W. (Yale & Towne Manufacturing Co.). Feb. 15, 1946, No. 4768. [Class 44] In a revolving-barrel lock having key-set elements or tumblers controlling the positioning of locking elements or drivers, each of the former has surfaces to co-operate with at least two of the latter to release the lock; preferably the release surfaces of two of the key-set elements requiring to be aligned to release one locking element. The release surfaces may be constituted by depressions, each key-set element having two such depressions, each of which is aligned with depressions on adjacent elements to permit movement of a locking element. The depressions may be formed, for example on the side edges of sliding key-set elements. In the embodiment described, the key-set elements 15, Figs. 1 and 3, are in the form of sectors of a cylinder, and are axially movable by means of a key 16 having shoulders 17 so that halfconical depressions 35 on adjacent elements are aligned to permit inward movement of locking pins 27, the elements 15 and the pins 27 being housed in a rotatable cylinder or plug 13. Each element 15 has a bore 18 within which is housed a spring 19 fitting about a post 20, the posts 20 projecting from a plate 21 rotating, in the cylinder 10, and carrying the bar 23 which operates the lock. The locking pins 27 are pressed inwardly by leaf springs 28, but in the locked position, as shown in Fig. 1, their upper ends, of the shape shown, lie within conical bores 33 in the cylinder 10. This formation of the pins and bores prevents pick-. ing by the application of a torque to the plug 13. Each element 15 is formed with at least one depression 35 at each side edge, and two such depressions are brought together by movement of the elements 15 to allow each pin 27 to move inwardly to release the plug 13 for rotation. False non-effective depressions 35 may be provided. The posts 20 are made weaker than the pins 27 so that force applied to a tool inserted in the key-way will shear the posts rather than the pins.