Device in an automobile for preventing an accidental locking of a steering shaft in such a type of a locking system as a rotor of a cylinder lock is provided with a lock position of the steering shaft. The device comprises a stop provided in said rotor or in an associating locking bolt and a manually-operable means usually urged by a spring means to engage with said stop thereby to check a further rotation of the rotor from an OFF position of an ignition switch further to said lock position. For turning the rotor from the OFF position to the lock position, two manipulations, first, shifting said-manually operable means against the spring means to release it from an engagement with said stop and, second, turning the rotor with a key must be performed simultaneously. Thus constructed, the device can well prevent a danger of an accidental locking of the steering shaft while driving and assure a safety driving of the automobile.

A steering lock assembly to lock and unlock a steering shaft by use of a key. The rotation of the rotor through key manipulation is controlled by a knob provided back of the steering lock assembly with a spacing to make impossible one-hand operation. Only when the knob is depressed, control means permits the rotor to rotate from an unlock position to a lock position with the result that car accidents due to inadvertent pulling out of the key on a down-hill ride is avoided.

A pin-tumbler lock and method of use thereof has an inside cylinder and conventional outside cylinder. The inside cylinder operates with a pin-tumbler key but cannot be operated by the key that operates the outside cylinder. The pin-tumbler key is retained automatically in the inside cylinder once inserted but can be manually released by using an appropriate tool. The inside cylinder retains the pin-tumbler key because the pins become misaligned when the pin-tumbler key is inserted. Previous locks can be a fire hazard or can be burglarized too easily.

Sensors such as switches are arranged to detect the insertion of a key into a key cylinder, the rotation of the key to one or more operative positions, the position of a transmission shift level, the depressions of a brake pedal and the like, and to produce signals which are processed by logic circuits in a manner to determine the energization mode and timing of the solenoid or the like motor arrangement in a manner which locks or releases a safety button which must be pressed before the steering column of a vehicle can be locked. The mechanism which performs the locking operation is mounted on the exterior of the housing in which the key cylinder is disposed, thus facilitating assembly.

An ignition lock system for a motor vehicle includes an electronic ignition key and an electronic ignition lock having a key receptacle. The electronic ignition key can be inserted into the key receptacle to exchange coded operating signals, the key receptacle, together with the inserted electronic ignition key, being movable out of an initial position into at least one operating position. A mechanical blocking device is provided in the key receptacle, which blocks the electronic ignition key against withdrawal from the key receptacle in the operating position. The mechanical blocking device cooperates with the electronic ignition key in such a way that the electronic ignition key and/or the key receptacle is irreversibly damaged when blocking actions of the mechanical blocking device are forcibly overcome.