Patent ID: 8621902

Claim:
A programmable lock cylinder assembly comprising: a lock housing having a body defining a tubular opening; a cylinder plug having a body mounted for rotation within the tubular opening, the cylinder plug including a keyway extending therein; a set of rack pins in the cylinder plug and moveable between a locked position wherein the cylinder plug is rotationally locked relative to the housing and an unlocked position wherein the cylinder plug is rotational relative to the housing, the set of rack pins includes at least a first subset of rack pins and a second subset of rack pins, the first subset of rack pins having at least two operable bitting configurations where one of the at least two bitting configurations of the first subset of rack pins is separated by a pre-determined number of bittings from the other of the at least two bitting configurations, and the second subset of rack pins having a different bitting configuration than the first subset of rack pins whereby the bitting configurations of the second subset of rack pins are separated by a different pre-determined number of bittings than the pre-determined number of bittings of the first subset of rack pins such that the lock cylinder assembly is master keyable, wherein each rack pin includes serrations and a notch formed in the serrations for receiving a locking sidebar, wherein a height dimension of the notch on the rack pins of the first subset of rack pins differs from the height dimension of the notch on the rack pins of the second subset of rack pins; and a re-combinating assembly within the cylinder plug configured to facilitate reprogramming of the rack pins without removing the rack pins from the cylinder plug.