Abstract: A lock which is adapted to transduce the code from a key by electronic means is constructed to resemble the form and functionality of a conventional mechanical cylinder lock. A main casing houses the bolt, a rotatable thrower or cam for retracting the bolt, an electromechanical release mechanism which normally blocks rotation of the thrower, and a processor to control the release mechanism in response to the detected key code. The electronic reading means are located in association with the keyway of a rotatable barrel in a cylinder unit manufactured as a separate unit from the main casing. The thrower and barrel have respective cooperating mechanical couplings and the main casing and cylinder unit have respective cooperating electrical connectors. The lock is therefore assembled by attaching the cylinder unit to the outside of the main casing, thus establishing a rotary driving connection from the barrel to the thrower and establishing an electrical connection from the key reader to the processor.

Abstract: An "electronic" lock has a thrower with a radial lug for extending and retracting the bolt when turned by a key carrying a proper code. Turning of the thrower through a sufficient distance to shift the bolt is normally blocked by a dogging lever with which the thrower lug abuts. The thrower lug also sweeps a cam track on a second lever so as to pivot the latter during initial turning movement of the thrower away from its rest position. The second lever carries an electromagnet. While the electromagnet remains de-energized there is no interaction between the two levers so that the second lever can pivot independently of the first and turning of the thrower remains limited. When a correct key code is detected, however, the electromagnet is energized to hold the two levers together. Initial turning of the thrower thereby causes the second lever to carry the dogging lever away from its blocking position and thus free the thrower for 360.degree. movement.