Anti-manipulation device for permutation locks
OwnerJames Main, Leslie Robert Moss +1inventors
InventorsJames Main, Leslie Robert Moss, Ralph Perryman
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Abstract
This invention is concerned with permutation locks having a wheel pack comprising a plurality of rotatable permutation discs, each having a recess which must be correctly aligned before the bolt of the lock can be withdrawn. One known method for determining the positions of the permutation discs is by analysis of X-radiation which has passed through the wheel pack parallel to the axis of rotation of the discs. In locks according to this invention, the opacity of the wheel pack to penetrating electromagnetic radiation along any line parallel to the axis of rotation of the discs is independent of their orientation.
Claims4
A permutation lock having a wheel pack comprising a plurality of rotatable permutation discs each of which has a peripheral portion and a radially extending recess in the peripheral portion thereof, a bolt, and a fence which moves with the bolt and which engages in the recesses of said discs when the bolt is in a retracted position, wherein the construction of the wheel pack is such that the total thickness, in a direction parallel to the axis of rotation of the permutation discs, of the material of each permutation disc is substantially constant along any cylindrical locus concentric with the said axis and passing through the recess.
Dependencies are inferred from the claim text.