Abstract: A radio wave signal control arrangement for a lock mounted on a vehicle door which is controlled on an on-off basis. A portable key signal generator is provided which issues a radio wave instruction signal. A stationary lock controller receives the instruction signal. An actuator is mounted on the vehicle door and is operated by the lock controller when the latter is actuated by reception of the radio wave instruction signal. An outside accessible switch is mounted on the vehicle door, and provides a door-lock state reversing enabling signal to the lock controller to unlock the lock if it is locked or to lock the lock if it is unlocked.

Abstract: A device for detecting the removal of a cylinder lock used on cars, trunks, etc. when an unjust force is applied to the cylinder lock. The device also detects the locked and unlocked conditions of the cylinder lock. Magnets and magnetic sensor switches are used. A magnetic shield plate shields the flow of magnetic flux between the magnet and the magnetic sensor switch. When an unjust force is applied to the cylinder lock to take off the cylinder lock, the magnetic shield plate will be removed from between the magnet and the magnetic sensor switch, causing the magnet to energize the magnetic sensor switch, thereby detecting the removal of the cylinder lock.In addition, when the cylinder lock is turned by a key, another magnet connected to a rotor of fixed on the cylinder lock approaches either of a pair of magnetic sensor switches, whereby the locked and unlocked conditions of the cylinder lock are detected.

Abstract: There is provided a keyless entry system in which a permanent code, or first code, and a user's code, or second code are used. The second code is presettable in conjunction with use of the first code. When the first code is inputted, the system gets ready for presetting a desired number of code elements consituting the second code. According to the invention, the system is provided with a circuit for variably presetting the number of the code elements, which circuit is responsive to the first code to vary the presetted number of the second code elements to that inputted following to the input of the first code. Preferably, the keyless entry system further includes a theft prevention circuit which inhibits input of a code for a given period of time when wrong codes are inputted more than a predetermined number of times.

Abstract: A door locking system for an automotive vehicle including an anti-theft automatic door locking apparatus by which the door can automatically be locked a fixed time period after the door has been closed in the case where an ignition switch is open and the ignition switch is left at the steering-lock position. The door locking system according to the present invention comprises an ignition switch for detecting the state in which the engine is not operating, a door-close switch for detecting the state where the vehicle doors are closed, a timer for delaying the automatic locking of the doors for a fixed time period, and an AND gate, in addition to the conventional door locking system.

Abstract: A mischief preventive electronic lock device has a mischief prevention system which prevents lock/unlock operation for a given period of time after a pushbutton input unit has been operated extraordinarily often in comparison with usual number of keystrokes required for entry of an input code. The electronic lock device is normally operated to lock/unlock a door matching by the input code with a preset code. The mischief prevention system is adapted to count the number of keystrokes from the input unit to perform the foregoing preventive operation whenever the keystroke count exceeds a predetermined value. The mischief prevention system permits further input after expiration of the given period. This discourages trial-and-error attempts to satisfactorily protect the electronic lock device from mischief.

Abstract: An electronical locking/unlocking system by which a door can be unlocked when a single switch is depressed repeatedly by an operator in time with a musical rhythm which he knows or in accordance with a Morse-type code. The electronical locking/unlocking system according to the present invention comprises a single switch for generating a predetermined series of on-time interval and off-time interval signals, a first counting unit for counting the on-time intervals, a second counting unit for counting the off-time intervals, a memory unit for previously storing reference ratios of on-time intervals to off-time intervals, a calculating unit for dividing the counted on-time intervals by the counted off-time intervals, a comparating unit for comparing the calculated values with the reference values, a third counting unit for counting the number of accurate on/off ratios up to a predetermined number, and an unlocking actuator.

Abstract: An electronic door locking system for an automotive vehicle with which vehicle doors can be locked, by depressing a proper push-button type switch representative of a predetermined door-locking digit, only when an ignition key is brought near the switch. Therefore, it is possible to lock vehicle doors without leaving the ignition key in the keyhole, with the result that the vehicle can be prevented from being stolen by a thief when parked. The electronic door locking system according to present invention comprises means for detecting the presence of the ignition key brought near the switch and an AND gate for passing a locking command signal to a door lock/unlock actuating solenoid only when the presence of the key is detected, in addition to the conventional electronic door locking system.