Electronic locking device having key and lock parts interacting via electrical pulses

An electronic locking device of the type having pulse-operated interacting key and lock units each including a random number generator, data processing means connected to the random number generator and communication means connected to the random number generator and to the data processing means, the lock unit being connectable to an object to be locked and including a bolt control means which in response to an assigned key unit moves between an operative and an inoperative position, at least the lock unit generating, in response to a start pulse, a sequence of digital input data in the form of electrical pulses which are transmitted to the key unit, the key and lock units being preprogrammed respectively for a specific association between the unanimous input and output data generated at each unit, the two specific associations being in tune only for key and lock units which belong one to another, whereby the tuned up associations serve as an electric code for the units, a common comparator arranged at least in the lock unit for comparing the pulse sequences of the output data and for generating an actuation pulse for the bolt control means when the two pulse sequences are in tune, comprising

• means for generating a start pulse at the key unit;
• said input data being at least one randomized random number;
• two-stage coding means for generating an electronic code characteristic of the associated pair of key and lock units, one coding stage including means for performing in each unit computations according to a preset algorithm whereby the resulting values of these computations depend on the input random number, the other stage of the coding means including means for generating from the results of the computations in the first-mentioned stage a fragmented number derived according to a preset formula or rule which is independent from the input random number;
• and
• means for applying the fragmented numbers generated at respective key and lock units as said output data to said common comparator.