Locking device for a lock, especially a vehicle-door lock having two different keys

摘要

The invention relates to a locking device for a lock, especially a vehicle lock having two different keys, namely a normal key (N-key) and a special key (S-key) which, in addition to normal securing, also brings about a special securing of the lock. So that a space-saving construction is achieved and there is nevertheless a high degree of safety against probing in break-in attempts, the cylinder core of the lock is provided with perforations for electromagnetic radiation and the S-key is provided with potential conduction points for the electromagnetic radiation which, when the S-key is inserted, are aligned with the passages in the cylinder core. The cylinder guide surrounding the cylinder core is respectively provided, in the path of rotation of the cylinder-core passages, with mutually aligned transmitters and receivers for the electromagnetic radiation which define electromagnetic operating planes offset in terms of rotation relative to the zero position of the cylinder core which allows the N-key and S-key to be inserted and withdrawn. The receivers are each connected to an electronic evaluator which is programmed to the conduction-point code of the S-key and the output of which is connected to the lock members of the special securing device. <IMAGE>