Method and circuit arrangement for the electronically controlled release of door, safe and function locks using electronically coded keys

Abstract

A safety system comprising closure means, hereinafter termed locks, and associated closure release means, hereinafter termed keys, which operate electronically and which grant access. The lock release is dependent on the agreement or coincidence of a variable lock/key code pair. Random codes are employed which are altered either automatically each time a lock is actuated or only as required. A plurality of locks can be actuated by a common key which possesses another variable code for each lock. In addition, a plurality of keys can actuate a common lock which possesses another variable code for every key. Both possibilities can be combined, since every key and every lock possesses another associated code pair whose association is automatically produced when a lock is actuated. By means of a central key which is safeguarded in the same manner, the user can produce and vary any desired lock/key association so as to eliminate misuse. All keys and locks operate independently of one another and do not require any coordination center. Lost keys can be made immediately from standardized keys with the aid of the central key, the lost key being automatically blocked or eliminated. Moreover, the central key permits the user to correct malfunctions of the key or lock fits. Disturbances or malfunctions of the system or the loss of the central key are not critical, since in such a case an emergency code known only to the manufacturer or an authorized safety official can be read into the affected locks either automatically or manually triggered. Since no key contains the emergency code and since this can be different for every lock, there is no restriction of safety. Auxiliary measures are included which prevent the respective key code from unfortunately being read out of the apparatus. The different users can also be automatically identified or, if desired, registered automatically with the aid of the employed code association. This also prevents misuse. Time-outs and similar safeguards can also be included in the system.

Dependencies are inferred from the claim text.