Abstract: The invention adapts to an electronic lock comprising a housing, and a plug supported for rotation within the housing and having a keyway to receive the blade of a key which rotates the plug during operation of the locking apparatus. A locking member is movable into engagement with the plug to prevent the movement of the plug and the operation of the locking apparatus and movable out of engagement with the plug to allow the rotation of the plug and the operation of the locking apparatus. A solenoid having a core coupled to the locking member moves the locking member into and out of engagement with the plug. A permanent magnet is movable between a first position to receive and hold the solenoid core to maintain the locking member out of engagement with the plug, and a second position to release the solenoid core, and a driving means moves the magnet in at least one direction between the first and second positions.

Abstract: A security system has a key including a transmitter for emitting a coded signal and a receiver for the signal and connected to a latch of the vehicle for unlocking a door secured by the latch only when the coded signal is received. A column bolt is displaceable in a housing fixed around the steering column between a locking position preventing the column from rotating and a freeing position. A barrel rotatable in the housing is formed with an axially open pocket generally complementary to the key. A switch is actuatable in one end position of the barrel for starting the vehicle and a locking pin is displaceable in the barrel and engageable into the pocket and into a lateral recess of the key when same is fitted in the pocket. A lever can engage in the recess of the barrel in the other of the end positions and can also engage in this other end position with the pin to push same into the pocket and into the recess of the key therein.

Abstract: An automotive antitheft key arrangement for locking and unlocking an automotive vehicular door and for operating an ignition system includes a transmitter, first and second receiving means for receiving an input code signal sent from the transmitter unit, and a discriminator including a comparator which compares the input code signal received by the first or second receiving means with a present code signal. The discriminator produces a first or second comparator output when these signals match each other. In response to the first or second comparator output, electrical power is applied to a door lock mechanism for locking and unlocking the door or a starter motor for causing the engine starting operation. The door lock system further includes means for preventing either the first or second comparator output from being produced in response to turn ON or OFF of a starting switch so that the first comparator output is not produced when the second comparator output is produced, and vice versa.

Abstract: An electronic locking system and method provides a control unit in a receiver to open a lock of a locking system when a transmission sequence output by a transmitter of the electronic locking system coincides with a reference sequence within a re-synchronization region in the receiver, the transmission sequence being formed by a user by repeated actuation of the transmitter and stored in a mark memory of the receiver. If necessary, the synchronization unit synchronizes the reference generator to the most recent transmission mark of the transmission sequence.

Abstract: An anti-theft device for automobile vehicles disables the vehicle's starter ignition system unless a coded resistive element is inserted into the device by the vehicle's operator. A control system senses the value of the coded resistive element and enables the starter system if the sensed value is correct. A latching circuit latches-in enablement of the starter system after an arming switch is activated and the resistive element has been removed, serving to provide a valet function. A lock-out circuit prevents enablement of the starter system for a prescribed time period following an unauthorized attempt at enabling the system, as when an incorrect resistive element is inserted into the device. The device employs a normally closed relay to enable the starter system so that failure of those portions of the device which are most likely to fall does not affect normal operation of the starter system.

Abstract: An electronic locking system including a lock cylinder having an electronically actuable release assembly which is selectively enabled to disengage a pin from a cylinder plug, to permit the rotation of the plug by an inserted key. The lock cylinder and key each contain non-volatile, electronically alterable memory devices, such as EEPROM integrated circuits, which house keying system codes. The key EEPROM is preferably housed within the key blade, in a key design which closely resembles a traditional mechanical key. The release mechanism incorporates a locking pin which is moveable between plug-engaging and non-engaging positions, along a radius of the lock cylinder. The release mechanism may include a primary actuator which directly moves the locking pin, or may act indirectly upon the locking pin via a latching member.

Abstract: In this arrangement the lock may be operated only if a bolt is withdrawn. Such bolt is driven by a motor controlled by a micro-processor associated with a memory in which time slots for removal of the ban on lock operation are stored. These time slots are constantly compared with the time of day by the micro-processor which removes the ban by controlling the motor only if the time of day is within a time slot. Blocking intervals having precedence over the time slots may intervene so as to prevent removal of the ban during such intervals. A keyboard following checking of an authorizing code permits eventual modification of the time slots and the blocking intervals. The arrangement finds use for safes and other protected enclosures.

Abstract: A keyless entry system, is associated with a steering lock device. The steering lock device includes an electrically operated actuator for operating the steering lock device between locking and unlocking positions. Steering locking and unlocking operation is triggered by a predetermined vehicle operation, such as closing of the vehicular doors. A predetermined steering lock condition is checked as triggered the steering locking and unlocking operation. Steering locking and unlocking operation is carried out when the operation is triggered and the steering lock condition is satisfied.

Abstract: An antenna for an automotive keyless entry system can ensure radio-wave transmission between a transmitter and a controller and can be conveniently mounted on a vehicle body. The antenna for an automotive keyless entry system, has a first planar antenna loop, and a second antenna loop disposed within the first antenna loop and lying in the plane thereof. The axis of the second antenna loop is substantially perpendicular to the axis of the first antenna loop. The first and second antenna loops form an antenna assembly which can be conveniently mounted on the vehicle body as, for example, within a door mirror of the vehicle.

Abstract: A system for securing a building complex incorporating a plurality of lockable access locations, including a keypad-operated remote unit at each access location coupled for communication with a control station through a communication network. Access locations are room doors, as of a hotel or an apartment building and the remote units are grouped by floor, each floor having a sub-controller to relay messages and perform control functions. The control station includes a desk unit with a keypad for entering floor-related access code information as chosen by a guest and a separate keyboard for assignment of a room number by a desk clerk which addresses a remote unit. Access codes are stored at remote units located at the assigned rooms so that a room can be unlocked only by manual entry of the proper access code on a keypad of the remote unit. Each remote unit functions independently to open a door associated with it and remains operable even if other portions of the system malfunction.

Abstract: A system for the locking and/or unlocking of a security device, particularly an automobile locking device, comprising a transmitting device for transmitting coded data recording, a receiving device for receiving the coded data recording, a transmitter-end storage and a receiver-end storage for storing codes and a comparator for comparing the received data recording with the stored data recording, a control signal being adapted to be given off to the security device from the receiving device in the event that said data agree. The receiving device has a signal generator to produce several further coded data which are stored in the transmitting device and in the receiving device and can be employed upon the subsequent use of the system. The further coded data recording may be random number and/or algorithms for changing the random numbers. The production of the further coded data recording is effected preferably upon actuation of the ignition lock.

Abstract: A security system includes a microcomputer with an auxiliary read-only memory and a key device including a similar read-only memory, each of the read-only memories containing corresponding pluralities of corresponding binary combination codes. Under the control of the microcomputer the codes are read and compared. If the combinations and the sequence do not compare, the system will not unlock and an alarm will be generated. The read-only memories are of the programmable type, so that changes in the combinations and sequences can be accomplished easily. A plurality of visual indicators and an audible alarm provide the user and personnel in the secure area with information concerning the status of the system.

Abstract: The device consists of a key having a passive memory zone and a circulating register, the code contained in the passive zone being intended to be transferred to the circulating register when the key is introduced into a lock, so that the said code may be transferred from the circulating register to the lock to be compared there with a reference code contained in the lock. The key comprises a circuit which is provided with a counter which is incremented each time voltage is applied to the key and a system for resetting the counter to zero, when the code is successfully transferred from the key, so that after a number of attempts determined by the counter of unsuccessful transfer attempts, the passive memory zone is destroyed by the output signal emitted by the counter.

Abstract: An anti-theft device for an automobile with high reliability is proposed. The device detects an intrusion and a battery disconnection and disables the engine. The device is powered by a battery prepared exclusively for the device besides the main battery of the automobile. The battery is mounted on the same board as the device, therefore increasing the reliability of that device. The device is simple to operate. When the driver leaves the car and the doors are locked, the anti-theft device is activated. No additional operation is required from the driver. The anti-theft device is even more reliable with the use of a key which has a bar-code printed on its surface.

Abstract: An electronic lock system for positioning one or more deadbolts, and responsive to a passive signal encoded and imposed upon a radio carrier wave, the carrier wave being received and decoded and passed into a computer that controls operation of a drive for closed and opened positioning of the deadbolt, or deadbolts, the computer being responsive to an obstructed deadbolt, responsive to door opening and closing, and indicating the locked and unlocked condition of the system.

Abstract: A battery powered electronic lock includes a control for indicating low battery voltage and reserving a portion of the battery's energy for operating the lock upon insertion of maintenance or emergency keys.

Abstract: A keyless access control and security system especially adapted for use with an automobile and including a piezoelectric permutation touchpad unit which can be affixed, without requiring bodywork, to the outside of the vehicle's door in the key cylinder aperture. The touchpad is illuminated when touched and is therefore usable in the dark. The person seeking access must enter the correct access code combination on the touchpad to open the door and/or the trunk. The touchpad is connected to a remotely located logic circuit which controls access. The circuit provides for a signal of low intensity, indicating that a correction in the code entered into the touchpad should be made and, after a time delay, an alarm of high intensity, if no correction is made. Upon activation of the alarm, the head lights are flashed, the horn is sounded, or both.

Abstract: A keyless entry system can lock and unlock an automotive vehicle door, a trunk lid, a glove box and/or a steering column without an ignition key. The system comprises a transmitter producing a radio signal indicative of a preset unique code, and a controller receiving the radio signal and performing desired locking or unlocking operation when the code from the transmitter matches a preset code. A manual switch is provided to order the transmitter to transmit the code-indicative radio signal to the controller. The transmitter encloses a battery acting as a power source. A battery checker is provided to produce an alarm when the battery voltage becomes lower than a predetermined voltage.

Abstract: Safety mechanism for locks (electronic lock) comprising a pick-up performing the function of a key and a sensor performing the function of a lock part. The pick-up is provided with a pre-determined surface arrangement of magnetically permeable, preferably inactive material in the form of soft-iron pins forming exciting elements, which forms a code. For detecting the code of the pick-up, the sensor is provided with an arrangement of sensor elements in a surface matrix of the same geometrical extension, which sensor elements can be varied as to their ohmic resistance by a change in the distribution of the magnetic field lines and take the form of magnetically controllable magneto-resistors. The magneto-resistors are set up, preferably, in the manner of an integrated circuit.

Abstract: This invention relates to a button-type code car-switch controller, especially one which can turn on and off the car switches with the signal sent by the code operating circuit and control circuit formed by such electronic elements as transistor-transistor logic (TTL) and with the alarm interface circuit, can work together with various alarm systems so as to protect the car against thief, robbery and wire cutting-off. While the set code can be changed after the car switch is turned on, the alarm can be activated when a wrong code is keyed in. With this controller the car can be operated without conventional keys.

Abstract: For controlling a central locking installation and/or theft alarm of a motor vehicle a switch lock installation is provided which comprises at least one lock with mechanical tumblers for the mechanical locking and unlocking of a door or a bonnet of the motor vehicle. The tumblers form a first key secret. The key which blocks the tumblers carries an electrically, magnetically or optically readable information carrier for a second, operationally variable key secret. A reading device detects the information of the second key secret in a position in which the mechanical tumblers of the lock are released. If the key is moved in the opening direction of the lock, a control circuit compares the information read by the reading device with an ideal information stored in a memory circuit and controls the central locking installation and/or theft alarm accordingly.

Abstract: Key evaluating apparatus for receiving a key having a surface whose amplitude or height is variably coded and for sensing the coded key surface to provide a set of sample signals corresponding to a sequence of sampling points on the coded key surface. The key evaluating apparatus of this invention comprises a key follower suspended to follow the movement of the coded key surface as the key is inserted past a fixed point. A key movement responsive mechanism is responsive to the movement of the key follower for generating the set of signal samples corresponding to the sequence of sampling points of the coded key surface.

Abstract: An electronic locking system including a lock cylinder having an electronically actuable release assembly which is selectively enabled to disengage a pin from a cylinder plug, to permit the rotation of the plug by an inserted key. The lock cylinder and key each contain non-volatile, electronically alterable memory devices, such as EEPROM integrated circuits, which house keying system codes. The key EEPROM is preferably housed within the key blade, in a key design which closely resembles a traditional mechanical key without the usual bitting. The release mechanism incorporates a locking pin which is moveable between plug-engaging and non-engaging positions, along a radius of the lock cylinder. The release mechanism may include a primary actuator which directly moves the locking pin, or may act indirectly upon the locking pin via a latching member.

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: An encoded signal device employing a pulse generating means for generating plural encoded pulse trains. The pulse generating means is encoded so that a logical add signal of the plural pulse trains includes one pulse at each timing position of a pulse generation timing system. The logical add signal is utilized as a synchronizing signal in reading out the plural encoded pulse trains.

Abstract: An electronic safe has a secure housing including a lockable door thereto, a programmable control unit within said housing, a keyboard mounted on an external side of the housing and connected to the control unit, whereby a user can program a selected combination code into the control unit through the keyboard, a motor driven lock bolt for locking the door to the housing upon the programming of a combination code by a user and closing of the door, and a program control for recognizing entry of the selected combination code to open the lock bolt to permit access into the safe. The electronic safe further has a display for displaying the codes entered by the user, and an override device for randomly generating an alternate code and permitting access into the safe upon entry by the user of an override code corresponding to the alternate code. A pull-out component is also provided for altering the alternate code generating program in the event the security of the override code list has been breached.

Abstract: A burglarproof device which can facilitate the activation of an alarm system and can provide lock-out protection. It uses a set of correct-signal generating reed switches and a set of incorrect-signal generating reed switches to activate the alarm signal, and the input of a correct signal within the preset lock-out time after receipt of an incorrect signal will not be able to open the door lock or disarm the alarm system.

Abstract: The system is an electric control circuit and associated components including a door locking circuit and an ignition circuit. The ignition circuit is connected to the vehicle battery power through a latch circuit. The latch circuit has alternative "lock" and "unlock" modes for, respectively, connecting battery power to and disconnecting battery power from the ignition circuit. A code sensing circuit provides switching for the latch circuit. This circuit includes means for programming a preselected unlocking code. The code sensing circuit includes code inputting means which might be a push button pad, a barcode reader, an optical binary-code reader, or a magnetic reader; the inputting means being mounted on an entry door of the vehicle. The code sensing circuit includes comparator means for comparing the inputted code to the preprogrammed code for the sending of an unlocking signal to the latch circuit.

Abstract: The composite automatic control system for vehicle engine with theft prevention circuit serves the purpose of controlling the door lock and engine starting power supply. It comprises present correct keys S.sub.1, S.sub.2, S.sub.3 and error keys S.sub.4, S.sub.5. . . S.sub.10. Decoding of the system depends upon the pressing of keys in a sequential order of S.sub.1, S.sub.2, S.sub.3 at predetermined time intervals, for instance 5 seconds as set forth in the model circuit. Failure to do this within the time limit causes the previous input signal to be entirely nullified. The alarm is then triggered to prevent theft upon improper sequence of correct keys or input of error keys.

Abstract: An anti-theft device for automobile vehicles disables the vehicle's starter ignition system unless a coded resistive element is inserted into the device by the vehicle's operator. A control system senses the value of the coded resistive element and enables the starter system if the sensed value is correct. A latching circuit latches-in enablement of the starter system after an arming switch is activated and the resistive element has been removed, serving to provide a valet function. A lock-out circuit prevents enablement of the starter system for a prescribed time period following an unauthorized attempt at enabling the system, as when an incorrect resistive element is inserted into the device. The device employs a normally closed relay to enable the starter system so that failure of those portions of the device which are most likely to fail does not affect normal operation of the starter system.

Abstract: A portable case (2) is provided for emitting, in response to pressure on a push button (1), a control signal (S) coded in accordance with a code recorded in said case. Timing means (8) are provided for automatically neutralizing the code when a predetermined time has elapsed from a predetermined moment, which then makes the case inoperative.

Abstract: An apparatus and method for providing a universal electronic locking system (UELS) which controls an actuating device for a lock is disclosed. The system is composed of two elements, a signal-transmitting unit and a signal-receiving unit. The integrated circuit chip of the watch is expanded to include a programmable memory unit such that various codes may be entered in the watch and the codes may be changed at any interval desired by the operator. The signal-receiving unit comprises a photodetector for receiving an optical signal from the signal-transmitting unit and contains a programmable memory unit which is responsive to each and all codes contained in the signal-transmitting unit. Upon changing the code signal in the signal-transmitting unit, the memory unit of the signal-receiving unit may be reprogrammed so as to be responsive to the newly encoded signal and allow the latching mechanism of the lock system to be operated.

Abstract: A combination changing method is used in an access control system which includes one or more keys encoded at a central console with a function information code, a key identification information code, an operation select information code and a two-field key combination information code and one or more locks having at least one memory level in which a lock identification information code and a lock combination information code are stored. A key is initially inserted into a selected lock and the data from the key is transferred to the lock. The lock identification information code is first compared with the key identification information code. If there is no correspondence, power to the lock is turned off for a set period of time. If the identification information codes correspond, a test field of the key combination information code is compared with the lock combination information code. If these correspond, the lock opens.

Abstract: A circuit produces a control signal which is input through a bi-directional communication device to a removable circuit. The removable circuit is set to a first logic state which is a function of the control signal and thereafter steps through a sequence of logic states with each logic state being a function of the previous logic state. The entire sequence of logic states is represented by a state signal or code word which is a function of the control signal. The produced state signal is compared to a predetermined stored state signal. Access is enabled in response to the production of a proper sequence of logic states, as indicated by the comparison of the produced state signal to the predetermined stored state signal. Security is improved because without knowledge of the control signal input to the removable circuit, an unauthorized user cannot ascertain the code word.

Abstract: The invention proposes an improved keyless steering shaft lock arrangement which comprises a gearing unit operatively connected with an electric motor; a rotator operatively connected with output shaft means of the gearing unit; and a rod movable between a locking and an unlocking position to engage with and disengage from a reception recess on a steering shaft depending upon rotational position of said rotator. Operation of the arrangement is controlled by a combined electronic and electric control circuit. The control circuit includes several safety means adapted for cooperation with the conventional engine ignition circuit, engine-running sensor, and vehicle-running sensor, for assuring proper and safe cooperation among these constituents.

Abstract: A keyed lock in which a key transmits programmed high frequency pulses which are capacitively coupled to an electronic lock which processes and decodes the high frequency pulses and provides an unlocking signal when the programmed pulses match a preset lock program.

Abstract: An apparatus for use in a secure entry system including a case and a container carried by the case. A mechanism is carried by the case and the container movable between container retaining and container access positions. A retainer is provided which is receivable by said case and movable between latched and unlatched positions. First and second electromagnetic latch mechanisms are carried within the case for use in operation of the container and the retainer respectively. A power supply is provided in the case. Circuitry is mounted within the case and connects the power supply to the first and second electromagnetic latch mechanisms. A code actuated assembly is carried by the case and is connected to the circuitry for selectively operating the first and second electromagnetic latch mechanisms.

Abstract: A radio transmitting and receiving system for operating the doors of an automobile to locked or unlocked condition and unlocking the automobile trunk or hood. The unlocking code may also activate the electric power to the engine starter motor, hood and manual switches of the power door operating motor.

Abstract: An apparatus for mutual information transmission between an electronic lock and a key uses antenna coils at both the key and lock. A periodic signal is emitted from the lock and is received by the key upon activation of a key electronics and emission of a coded information signal. This returned signal received from the lock coil is briefly short-circuited or damped at the key side in order to produce a synchronization switch synchronizing the points in time of the signal appearance. Electronic converters are provided which, given the pre-condition that the short-circuit signal extends over a plurality of signal pulses, generate a digital signal corresponding to the short-circuit times.

Abstract: An apparatus for electronically controlling the activation of a lock-release mechanism comprising a small, lightweight portable housing that can be easily carried and includes electromechanical means for converting mechanical movement initiated by an operator to electrical signals and an energization source for powering both the electromechanical means and the lock-release mechanism. The lock-release mechanism includes an electronic decoder and detector for receiving the signals generated by the electromechanical means and for receiving power from the energization source within the portable housing. In response to a correct signal code, the electronic decoder and detector in the lock-release mechanism releases an associated lock, thereby freeing the structure secured by the lock.

Abstract: The present invention provides a safety lock actuatable with a flat key carrying a code. The code is digitally generated by a laser beam and is sensed by detector laser beam upon or after the introduction of the key into the lock. The digital coding is produced by means of burning discrete depressions into a suitable layer on the key with a sufficiently strong laser beam and the sensing of the coding is done by means of a weaker laser beam.

Abstract: An automatic system for identifying an authorized key utilized to lock and unlock a door lock and to record pertinent data attendant thereto is disclosed herein having a key sensing mechanism incorporated into a lock that operates a switch circuit to generate a key identification signal. A control circuit receives the signal as well as time and date information and introduces this data to a printer for producing a visual record of the door lock transaction. The authorized key is coded not only to lock and unlock the door lock but includes a plurality of identification number codes along a given length.

Abstract: An ignition lock for a motor vehicle has a cylinder provided with a recess into which the plunger of an electromagnet can project in the absence of energization of the electromagnet when the ignition switch is in the off position. A remote control circuit for operating the doors of the vehicle is independent of a second circuit for responding to the presence of an appropriate key in the cylinder while a control circuit is responsive to both of these previously mentioned circuits for energizing the electromagnet only when the appropriate signal is received from the remote control unit and when the proper key is inserted in the cylinder so that in the absence of the first-mentioned signal even the proper key will not cause retraction of the plunger to permit the ignition lock to be operated.

Abstract: An apparatus and method for providing a universal electronic locking system (UELS) which controls an actuating device for a lock is disclosed. The system is composed of two elements, a signal-transmitting unit and a signal-receiving unit. The signal-transmitting unit is envisioned, in one embodiment, as contained within a watch and powered by the power source of the watch so as to transmit an optical signal to the signal-receiving unit. The integrated circuit chip of the watch is expanded to include a programmable memory unit such that various codes may be entered in the watch and the codes may be changed at any interval desired by the operator. The digital display of the watch serves a dual purpose for displaying time and for entering key codes. The signal-receiving unit comprises a photodetector for receiving an optical signal from the signal-transmitting unit and contains a programmable memory unit which is responsive to each and all codes contained in the signal-transmitting unit.

Abstract: An electronic lock system for power positioning of a deadbolt, responsive to passive code combinations of tone frequencies imposed upon a radio frequency carrier wave, the code combinations being encoded and decoded with direct activation of switching to control operation of a motor drive for closed and opened positioning of said deadbolt.

Abstract: Device for identifying an information, particularly of an access control consisting of electronic lock and key part, wherein given approach of the key part toward the lock part, its oscillator part oscillates at a high frequency, the oscillation is picked up by the key part and, modulated with a frequency or pulse pattern serving as a key identifier, is transmitted back to the lock part and is further processed by the reception and recognition means at the lock side. The reciprocating transmission of the energy between the lock and key part is carried out by a wave coupling by means of antenna coils whereby an inductively coupled synchronization switch is produced in that an altered signal curve is produced at a first coil at the lock side, being produced, for example, by means of a more or less complete short at a second coil at the key side or by means of impressing energy on the second coil.

Abstract: A printed circuit board including a dielectric material having first and second major surfaces, a predetermined number of electrical conductors attached to the major surfaces, a plurality of slots in the board, the slots beginning at the free edge of the board and continuing inwardly for a predetermined length, a portion of the electrical conductors lying parallel and adjacent to a portion of the longitudinal axis of the slots on both of the major surfaces, and a "U" shaped current carrying connector inserted into one of the slots the terminal free edges thereof in mechanical engagement with a preselected conductor of the first surface and a preselected conductor of the second surface forming an electrical path there between.

Abstract: An electrical circuit, the starting circuit for a motor vehicle for example, is selectively enabled by a control circuit which includes a magnetic field responsive switching device. Proper positioning of a magnet which provides a field of the appropriate polarity and strength relative to the switching device results in the energization of a relay which has contacts connected in series with the circuit being controlled. In the motor vehicle application, operation of the ignition switch within a pre-determined time subsequent to removal of the magnet will latch the relay in the energized state.

Abstract: An operating scheme for electronic locks wherein both the key and the lock have a first and second combination. The lock will open when the first key combination equals the first lock combination and the second key combination equals the second lock combination. The lock recombinates to the first key combination and the second key combination when the first key combination equals the second lock combination.

Abstract: Disclosed is an electronic locking device including electrically interacting key part and lock part each including electronic data processor with an inner code which is particular for a pair of key and lock units which belong one to another. To increase the number of variations and to inhibit the breaking of the code, the latter is generated in two stages whereby the input magnitudes for the code are retrieved from a collection of random numbers randomly generated in each unit. In the first stage of the coding process, the input magnitudes are subjected to computation according to a definite algorithm. In the second stage, only a fragment of the computation result is used and arranged according to a definite rule or formula to serve as output magnitudes for a comparator where the final arrangement of the fragments formed in respective units is tested as to mutual agreement. In the case of an agreement, a switching pulse is generated which activates bolt control mechanism in the locking unit.