Patent ID: 7370503

Claim:
A locking system comprising: a plurality of safety keys and locking cylinders; each of the locking cylinders having a stator and a rotor having at least one rotor control surface, a front end, a rear end, and a keyway having parallel sides, wherein a width of the rotor control surface is less than that of the keyway; and each of the safety keys having a shank which is provided with a plurality of first shank control surfaces on the upper surface of the shank which position tumblers in a body of the rotor and a front end and a rear end; wherein the at least one rotor control surface is located on the front end of the rotor and engages with a second shank control surface which is recessed below the upper and/or the lower surface of the shank and arranged at the rear end of the shank; wherein a lug projecting transverse to the plane of the shank is fixed on the rear end of the shank and engages a corresponding first recess on front of the rotor, the first recess having sides perpendicular to the sides of the keyway, wherein the lugs of the plurality of safety keys have different shapes or dimensions in order to increase the number of locking arrangements, and wherein the rotor control surfaces of the rotors are formed by second recesses of different extents or in different positions corresponding to different shapes or dimensions of the second shank control surface arranged at the rear end of the shank.