Patent GB-583215-A (GB)
Title: Improvements in and relating to cylinder locks
IPC: E05B29/00
Filed: 1942-07-28
Abstract: 583,215. Revolving-barrel locks. MEFINA SOC. ANON. July 28, 1942, No. 10545. Convention date, Aug. 18, 1941. [Class 44] In a revolving barrel lock of the kind built up from any desired number of guide discs 10 each of which has, in one face, a grooved recess slidably guiding a diametrically movable plate tumbler 16 biassed by springs 13 to project from one side or other of the general cylindrical surface of the assembled discs to engage with recesses in a casing, not shown, the discs have registering apertures to receive pins 17 by which the discs are held against relative angular displacement, and each tumbler has recesses 23 to receive the springs 13, one end of each spring bearing against an end face of the corresponding recess, the other end bearing against a pin 17, whilst the other end face of the recess co-operates with the pin to limit the movement of the tumbler under the action of the spring. The discs are identical in size and shape, and the tumblers differ. as regards the disposition of the recesses 23. Disc and tumblers have slots 10a to allow passage of the key, and the edge of the key may co-operate with an end of the slot in each tumbler to retract the tumbler against action of the spring. As shown, however, the key 18 has grooved sides to provide suitably-shaped tumbler-operating surfaces 19, 20, 21, 22 which co-operate with inwardly-directed projections 25 on the tumblers. As only one of the surfaces 19-22 need be effective, a master key may be provided in which the different surfaces operate different locks. The Specification as open to inspection under Sect. 91 also describes various other forms of revolving barrel lock in which the tumblers of a lock may be correctly operated by two or more different keys, so that one key may be individual to the lock, whilst another serves as a master key for operating a number of locks. In one form cylindrical pin-tumblers are housed in radial boxes in the barrel and casing in the usual way, but the inner end of the tumbler has a portion reduced in diameter to leave a nipple-like projection. The edge of one key is contoured to co-operate with the ends of the nipples. The other key has a groove which receives but does not co-operate with the nipples, whilst the edges of the side-walls of the groove are contoured to co-operate with the shoulders at the bases of the nipples. Another form has tumblers of rectangular cross-section arranged side by side in registering longitudinal slots of the barrel and casing and driven inwards by one end of an arcuate blade spring, one to each tumbler. The inner end of each tumbler has a central tongue, the tongues being aligned to form a composite rib received in the grooved edge of a key, the side walls having contoured edges co-operating with the shoulders on the tumblers at each side of the tongues. Another key has its edge contoured to co-operate with the ends of the tongues. A modification of this form has the tongue formed at one side, one key having its bit off-set to that side to co-operate with the shoulders. Other forms have plate tumblers generally resembling those described above but with internal projections at the sides or ends of the central aperture and co-operating with grooved or ingrooved keys, or having stepped recesses formed in the edges of the central aperture co-operating with ribs of difierent widths and depths on the keys. This subject-matter does not appear in the Specification as accepted.