Electro-mechanical system for determining key cuts for tumbler and wafer locks

A system for decoding tumbler locks and wafer locks having a rotatably mounted cylindrical plug having an elongated key receiving slot interactive with a series of slideable members spring urged orthogonally toward said slot and having different travel distances relative to flush fit with the surface of said plug, said flush fit establishing a shear line which permits rotation of the plug, said system comprising:

• a) a probe device having the general contour of a key expected to fit within said key receiving slot and having:
• 1) a straight shank fabricated of electrically insulative material and elongated between forward and rearward extremities and bounded by opposed flat side surfaces and straight parallel upper and lower edge surfaces, and terminating in a tip portion having an oblique ramp surface extending forwardly from said upper edge surface and convergent toward said lower edge surface, said ramp surface configured to sequentially contact said slideable members,
• 2) a series of spaced apart electrical conductors embedded within said shank in parallel relationship to said edge surfaces and forwardly terminating in electrical contacts in said ramp surface, and
• 3) a head portion associated with the rearward extremity of said shank to facilitate manipulation of the probe device, and equipped with electrical terminals interactive with each electrical conductor,
• b) electronic monitoring and display means interactive with said electrical conductors by way of said terminals and serving to indicate an individual conductor and its distance from the upper edge surface of said shank, said distance corresponding to the travel distance of a slideable member touching the corresponding electrical contact,
• c) a source of low voltage direct current adapted to flow through said lock, shank and electronic monitoring and display means, and
• d) correlation means for associating the indicated travel distance with a particular slideable member.