A lock and key mechanism reduces exposure to lock picking by including an extension into a key slot to receive and conceal tapered end portions of key pins. The only portions of key pins exposed in a key slot are cylindrical portions that are difficult to move from a resting position. A key includes a beveled leading edge and a spring-loaded pin activation element at the leading edge of the key. As the key is inserted into the key slot, the spring-loaded pin activation element is compressed to permit entry into the key slot. As the pin activation element reaches a pin, an aperture in the extension allows the spring-loaded pin activation element to move toward the key pin and move the key pin from its resting position. In this activated position, the tapered end portion of the key pin is exposed for further activation by the beveled leading edge of the key. The process is repeated until the pin activation element engages and activates each successive key pin and allows full insertion of the key.

A lock cylinder has a reset condition wherein the lock cylinder can be put into a "learn" mode. In the "learn" mode, the original key can be removed and replaced by replacement key and, when the replacement key is removed, the lock cylinder 10 is rekeyed to the new key. The original key no longer operates the rekeyed lock cylinder 10.

A re-keyable lockset that employs pairs of first and second pins. Coupling of the first and second pins to one another defines a key profile for a mating key. A second key with a different key profile may be installed to the lockset when the first and second pins are uncoupled from one another. Thereafter, the first and second pins may be re-coupled to one another to define the key profile of a new mating key. A method for re-keying a lockset is also provided.

A method and assembly for preventing unauthorized manipulation of common cylinder locks, as executed by use of the principles of the Bumpkey or Blowgun methods. The pin assembly, containing a tumbler pin and a driver pin, is adapted so as to alter linear displacement thereof, by forming a recession in one of the pins contained in the pin assembly , and an engagement means, in the other of the pins, for engaging the recession, such that when an impact-driven blow of a given intensity is applied so as to linearly displace the tumbler and driver pins, the pin engagement means engages the pin recession, strongly binding the tumbler and driver pins together, thereby, blocking the shear line and, consequently, preventing unauthorized manipulation of the common cylinder lock.

The present invention provides a lock keying system comprising: a lock cylinder (10) comprising: a cylinder body (12); a plug assembly (14) disposed in the cylinder body (12) and comprising a plurality of pins (113) and a one-to-one corresponding plurality of racks (92) for relocating the plurality of pins (113); and a rack alignment tool receiving aperture (335) defined by the lock cylinder (10); and a rack alignment tool (310) comprising: a base plate (312); and a plurality of spaced elongated prongs (314); each prong from the plurality of prongs comprising a first longitudinal end adapted to engage a corresponding one of the plurality of racks (92), each prong from the plurality of prongs dimensioned lengthwise to relocate to a first predetermined position the corresponding one of the plurality of racks, the first predetermined position common to each of the plurality of racks, each prong from the plurality of prongs comprising a second longitudinal end connected to the base plate.