Abstract: A tamper indication system for use with combination locks can indicate or signal that unauthorized manipulation of one or more of the lock components has occurred. In one mode, the tamper indication system senses unauthorized retraction of the lock bolt. Unauthorized movement of the lock cover or combination dial can also be sensed. Sensing can be achieved by generating a mechanical action responsive to the unauthorized manipulation and converting the mechanical action into an electrical signal for sensing and indicating. The mechanical action can utilize a snap action motion generation system, non-contact means such as magnets or a spring biased switch.

Abstract: The electric lock system operates to block access to the room when a guest key has been used and the guest is detected as being present in the room. The lock blocks access to hotel staff and provides the guest greater privacy in the room. The lock system employs an electronic lock in combination with a motion detector for detecting the presence of the guest in the room.

Abstract: A system for preventing the automatic or inadvertent opening of an aircraft door or access hatch that has not been closed and locked properly provides an increase in the overall flight safety of aircraft. The system includes a door monitoring system (1), which is connected to at least one of a cabin pressure control arrangement (4), a cabin temperature control arrangement (5), and an air tap system control arrangement (36). The door monitoring system (1) provides a signal indicating if at least one door or access hatch is not properly closed and locked. The controllers (4, 5, 36) receive the door monitor signal at respective inputs and also receive information necessary for determining the current flight configuration of the aircraft from various other aircraft systems, such as a landing gear control arrangement or an engine monitor arrangement.

Abstract: An electromagnetic door lock system employs an on-board microprocessor which is mounted in the housing for the electromagnet. The microprocessor is pre-programmed with possible operating parameters which are then selected at the installation site. In one embodiment, a contact activatable data reader is mounted at the housing to provide various input data for the microprocessor. The microprocessor is also capable of being interrogated to reveal the preset operating parameters and other information, including the identification of individuals requesting to egress through the associated doorway.

Abstract: An alarm system comprises a pair of interlocking components, which when separated causes an electrical switch operable in response there to change states and activate the alarm. The switch may be either a mechanical type device or a magnetic proximity type device. A cable may be attached to one or both components.

Abstract: A car audio apparatus mounted on an automobile and having a function for preventing theft, the car audio apparatus includes a main body portion fixed to the automobile and a front panel detachably mounted to the main body portion of the audio apparatus. The main body portion has a CPU and a first memory for storing a first secret code and the front panel has a second memory for storing a second secret code. The CPU is capable of respectively reading out the first and second secret codes from the first and second memories and comparing the first secret code with the second secret code so that when both secret codes agree, the CPU enables operation of the car audio apparatus and when both of the secret codes do not agree, the CPU inhibits the operation of the car audio apparatus.

Abstract: A personal alarm device having programmable deactivating, apparatus. The device includes a keypad by which a personal numerical code can be entered. This code is the only manner by which the alarm of the device can be shut off once activated. The code can be changed only by a user knowing the previously-entered deactivation code.

Abstract: The present invention relates to a method and apparatus for preventing an impaired person from operating a vehicle. The method includes a means for evaluating the level of the necessary skills for the safe operation of motorized vehicles, including automobiles, watercraft, aircraft and machinery. Once this level is determined on an individual basis, before operation of the motorized vehicle can be effected, each individual must match or surpass the safety level for enabling the ignition of the device. If the individual is impaired such as by drugs or alcohol use, the evidence is retained and the ignition disabled to prevent operation of the motorized vehicle. The apparatus includes an electronic module necessary to activate a test routine or program which also records the time, identity of the user, the number of times passed or failed and any attempts to tamper with our circumvent the system.

Abstract: A coded anti-theft system of the present invention employs a keyswitch board, a number of relays and timers, and a number of peripherals including a first sensing device, a second sensing device, a starting device, an indicating device, and an alarming device. Aggressive activity is sensed by the sensing devices to sound the alarming device. The system is set with a code by a user, and only the user who enters the correct code can enable the starting device to start the vehicle.

Abstract: A security box for mounting against a wall and capable of holding keys and the like. The security box having a cover capable of being in alternatively open and closed positions and two switches for use with a standard electrical alarm circuit. The box containing at least one lock and a latch that has a cammed surface, for securing the cover of the box in the closed position in conjunction with the lock. The box further having a latch receiving structure, for receiving the latch when the cover of the box is in the closed position, that is integral to the box. The latch being attached to the cover of the box and having a spring for disengaging the latch from the closed position in conjunction with the lock. The latch being capable of actuating at least one of the two switches and the lid of the box being able to actuate the other switch when either the lock or the lid of the box is tampered with.

Abstract: A delay means in a security apparatus for identifying a code of characters to authenticate access to the apparatus by matching an entered code with a stored value by a procedure which so enciphers the coded information as it is entered into the apparatus and displayed on a keyboard that disclosure of the code by observation of the entry operation is prevented. A delay timing circuit produces a delayed signal in the matching of the entered code and the stored value so that the length of the period of time for authentication is controllable.

Abstract: A container, e.g., case or bag, has an internal compartment with an access opening that is entirely closed with a cover having a clasp that cooperates with a latch of an electronic lock carried on the container. Preferably, the cover carries a key pad on its external surface and the key pad is in circuit to an alarm system that includes a control unit, power supply, motion and/or shock detector, and an audible alarm such as a siren. Most preferably, the power supply comprises one and preferably a pair of panels of solar cells which are also located on an external surface of the top cover. The container has one or more handles which can include a shoulder carrying strap. Preferably the container is formed of a thermally insulating material so that the container also serves as a cooler for beverage cans and the like.

Abstract: A vehicle anti-theft device includes a lock body carried on the vehicle and having a key receiving a slot. A pair of bore holes are spaced apart from each other in a predetermined pattern and extend through the lock body, which is transparent to a particular frequency of electromagnetic radiation. The key includes a first radiation reflective area aligned with one of the bore holes and a second non-reflective area aligned with the other bore hole. A systems controller includes a pair of radiation emitters and associated radiation detectors. A pair of fiber optic cables connect the radiation emitters and the radiation detectors to the bore holes. The systems controller generates control signals in response to radiation reflected from the key through the optic cables. If a proper pattern of radiation is reflected through the optic cables, the vehicle will be operated in a normal manner.

Abstract: An accessory for use with a vehicle, equipped with a vehicle anti-theft system, and an interrogator device for the anti-theft system. The accessory includes a connector arrangement for establishing between the vehicle anti-theft system and the interrogator device an electrical current carrying path which passes through the vehicle ignition lock cylinder mechanism. An ignition key arrangement is provided which is cooperable with the connected arrangement and permits mechanical operation of the vehicle ignition switch mechanism while the electrical current carrying path remains established.

Abstract: A portable, personal alarm system (A) which incorporates a loud audio alert (19, 9/10) that, when engaged, is unable to be removed from the user, or terminated without the cooperation thereof. The preferred embodiment of the present invention comprises a small, hand-held alarm system having a strap (5) with a locking mechanism for securely affixing the system to the user, compressed gas containment or electrical power for providing a loud audio horn alert, a locator light (4) for signalling the location of the user in dark areas, and a mechanism for selectively locking the horn alert in the "on" operating position which cannot be reactivated without unlocking the strap, which uses a precoded combination type lock. In use the push button (3) end (24) is placed within the palm so that the push button lies right under the fingers, with the main body (1) extending up along side of the inner side of the wrist.

Abstract: A selective call receiver allows reprogramming of the options stored within a code plug only after entry of a correct password. After a predetermined number of unsuccessful attempts to enter a correct password, the selective call receiver is user disabled such that the user may not reenable the selective call receiver without returning the receiver to the manufacturer or without replacing expensive components thereof.

Abstract: An anti-theft device for motorized vehicles consisting of three relays and a number of switches controlled by the relays that are wired into the existing electrical system of the vehicle. The first relay energizes in response to an electrical signal generated by the existing electrical system and controls the sequencing of the disarming steps. The second relay disarms the device when energized by a signal generated in the existing electrical system but only after the first relay has been energized. The third relay activates the alarm and/or disables the vehicle starter when energized. The third relay will energize when there is an attempt to start a vehicle without following the prescribed sequence of disarming steps and is prevented from sounding an alarm and/or disabling the vehicle starter by the second relay when the second relay is energized. A connector consisting of a male-female pair that is installed with the pair disconnected.

Abstract: Automobiles such as a cash carrying car, truck, police car and so on, are prevented from being ridden away during loading or unloading cash or goods or being robbed by robbers after having been forcibly stopped on road. When a door of the automobile is opened, a opened-door detection switch operates and a first-control means stores in its memory the switch's action and cuts off an engine start-up circuit. The engine can be restarted when a registered password is entered into the device through a password inputting means, whereby a second-control means stores the signal and enters a resetting signal into the first control means to restore the engine start-up circuit. At the same time, a resetting signal produced by a reset signal generating means is inputted into the second control means which is thereby restored to the initial state.

Abstract: A security system for controlling access to property having a user-operated keyboard to key in and reset a composite password code. An indicator visually displays at least one code symbol varying with time. A memory device stores a current composite password code including at least two code symbols so that upon entry of the keyed-in password code through the keyboard, one of the stored password code symbols is replaced directly by the time varying code symbol to form a regenerated, composite password code which is then compared with the keyed-in password code to grant access to the property when coincidence occurs between the keyed-in and the regenerated password codes. In response to non-coincidence, an alerting signal is generated to indicate the incorrect password condition.

Abstract: A vehicular anti-theft system, comprising: a mechanical key switch which can be turned with a matching mechanical key between a first angular position suitable for receiving the mechanical key therein and corresponding to an inoperative state of the vehicle and a second angular position corresponding to an operative state of the vehicle; electronic code matching circuit for detecting an electronic code signal transmitted from a transmitter incorporated in a part of the mechanical key; a control circuit which enables the vehicle when the mechanical key switch is turned with a matching key to the second angular position and the electronic code matching circuit has detected the matching code signal from the transmitter; a trigger circuit which acts upon the control circuit into detecting the matching code signal transmitted from the transmitter; wherein the trigger circuit is activated when the angular position of the mechanical key switch is set to a certain position preceding the position for starting the vehi

Abstract: According to the invention, the keyboard consists of a matrix of keys and variable visible indicia. Each of the variable visible indicia is associated with a key. Upon each keystroke on the keyboard, the system randomly changes the positions of all of the indicia on the matrix. Because the true value of any particular key is independent of the value displayed on the variable visible indicia, a casual observer can not learn the keystrokes being entered into the keyboard. If the code entered at the keyboard matches a stored value, the user is granted access.

Abstract: An aircraft exit door locking system in which an exit door is automatically locked depending on three dissimilar inputs to a logic system. The inputs are provided from acceleration, pressure, and motion sensors and are utilized in a manner whereby any two can determine whether the lock in the passenger cabin exit door will be energized or deenergized.

Abstract: A combination lock is provided with an additional security lock wherein an electrically operable solenoid, having an armature post normally biased outwardly of a solenoid body is mounted to the combination lock housing so as to position the armature post normally to block movement of either the combination lock bolt or the bolt release lever associated with the bolt. An electrical signal generator which may be an electrical switch, electronic lock mechanism or other electrical signal generating means, is provided for selectively operating the solenoid to retract the post from a bolt and/or bolt release lever blocking position to thereafter allow operation of the combination lock in an otherwise standard mechanical manipulation or electronic digital input of the main combination lock.

Abstract: The device can be applied to vehicles provided with an electronic control device for the vehicle engine. The protecting device for includes a keyboard for entering a user's code, a microprocessor for converting entered data coming from the keyboard into an output message containing the user's code, programmable and non-volatile memory for storing the code for unlocking the engine electronic control device, a microprocessor for comparing the unlocking code stored in the memory with the user's code contained in said message coming from the keyboard and unlocking the engine electronic control device when there is coincidence of the code contained in the memory with that contained in said output message, and the microprocessor and the memory being capable of effecting replacement of the unlocking code of the engine control device with a new unlocking code through action on the keyboard.

Abstract: A signal is received from a key having predetermined information. A resulting output signal is discriminated as to whether it represents the predetermined information. A predetermined anti-theft operation is actuated in response to output signals from first and second detectors indicating that at least one predetermined one of the covering members is closed and locked. Operation of the actuator is disabled in response to an output signal indicating that the received signal represents the predetermined information. The key includes a magnetic element forming first predetermined information, and light emitting elements for emitting infrared ray carrying second predetermined information. The predetermined anti-theft operation is actuated in response to an output signal from a third detector indicating that the key has been removed from a predetermined key hole, in addition to the output signals from the first and second detectors.

Abstract: A security device for credit cards, charge cards, cash cards and the like has a base, an integrally molded top partially extending along the length of the base and a lid pivotally secured to one end of the base. A key pad is recessed into the top. The lid has an electrically operated latch operated by the key pad. A cartridge for the cards is formed of cardboard bent into a serpentine format to provide an upper compartment and a lower compartment, each compartment being suitable for holding up to four cards each. The internal surfaces of the cartridge are coated with a pyrotechnic material and a heating coil is connected to the cartridge. An authorized user of the device has a personal code which when inputted via the key pad opens the lid. Incorrect input of the code causes a piezoelectric bleeper to sound. Two incorrect input sequences are permitted but on the third incorrect sequence the coil causes the pyrotechnic solution on the cartridge to heat up and destroy the cards within the device.

Abstract: A door lock includes circuitry for signalling the condition and operation of the lock. The lock has a bolt and two separate locking mechanisms, each operable to lock the bolt in its projected position. A bolt position signal switch generates a signal indicating the position of the bolt, either projected or retracted. Two lock signal switches are operated by the respective locking mechanisms to provide respective lock position signals. An intruder alarm using the lock includes a perimeter alarm subsystem, an interior alarm subsystem and an alarm conditioning control. The control is responsive to an unlocked condition of the door as signalled by the bolt position signal to disable both the perimeter and the interior alarm subsystems. When the door is locked from outside the premises protected, the control activates the perimeter and interior alarms, while locking of the door lock from inside locks the perimeter alarm only.

Abstract: A computer-controlled password lock system having a user operated keyboard to key in and reset a password. An indicator visually displays at least one code symbol varying with time. A memory device stores a current password including at least two code symbols so that upon entry of a keyed-in password code through the keyboard, one of the stored password code symbols of the current password is replaced by the time varying code symbol and password then compared with the keyed-in password code to generate a lock opening signal when coincidence occurs. In response to non-coincidence, an alerting signal is generated to indicate the incorrect password condition.

Abstract: This disclosure teaches a battery powered security indicating device which ttaches to the drawer of a safe. Sensors send drawer position and combination dial rotation signals to a microprocessor which in turn provides audio and or visual indication to the operator indicating when the drawer is open, when it is properly closed and when it is improperly locked.

Abstract: A safe for a loaded hand gun has a box which includes a receptacle for containing the gun. The receptacle has a bottom providing a mounting surface. A lid is hingedly mounted on the box and is movable between a closed position covering the receptacle and an open position in which the gun is accessible. A locking device normally holds the lid in its closed position, and a touch pad mechanism is operable only by authorized personnel provides for releasing the locking device when access to the gun is desired, permitting the lid to move to its open position. The touch pad may be a numerical touch pad, an alphabetical touch pad or a fingerprint indentification touch pad. The mounting surface has a mounting hole for use in attaching the safe to another structure. A pressure sensitive pad is affixed to the mounting surface at the mounting hole and is positioned to be overlapped by the head of a mounting screw.

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: An electronic security system which includes an infrared (IR) transmitter operable to broadcast a digital identification code signal at a pre-selectable programmable baud rate. Also included is an IR receiver responsive to the identification code signal received at the programmed baud rate. Further included is a comparator within the receiver to compare the received IR signal and its baud rate with baseline references. The comparator is operably coupled with an ignition circuit when the pre-selected code and baud rate matches the received digital code and baud rate. Both said transmitter and receiver are held within enclosures that are, on their external surfaces, IR transparent and visible light opaque. The internal surfaces of said enclosures are IR reflective.

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: An electronic lock and key includes an electronic key which produces a specific electric signal such as a frequency signal, photo signal or logic signal when inserted into the key holder of the lock; and an electronic lock which is comprised of a power source, a key holder, a lock signal generator, and a signal comparing circuit that compares the signal of said key and the signal of said lock signal generator.

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: An intrusion detection system of the type employing a keypad utilizing the keys to conventionally enable a user to key in a secret code capable of arming or disarming the system. The present apparatus includes a hold-down feature whereby if any one of the plurality of keys on the keypad is depressed for a predetermined interval, the apparatus detects the predetermined timing interval and transmits an audible sound to the user indicating that the requisite timing interval has transpired. Upon receipt of the audible sound, as depending upon the test to be performed, the user is thus informed that the system will now commence the test procedure as defined by the selected key. Thus the system includes apparatus for detecting the requisite timing interval. Upon detection of the requisite timing interval a storage means is activated, which storage means is associated with the selected key.

Abstract: A security installation with a portable transmitter and a receiver arranged at the object to be protected for an IR, respectively, UHF code signal which is changeable at least in part; alone the code signal of the transmitter can be changed upon random command and can be written into the associated storage device of the transmitter.

Abstract: A method and apparatus is disclosed for verifying whether a particular individual is a member of a predetermined group of authorized individuals. The subject apparatus is particularly suited for controlling access to a secure resource such as a computer network or data base. In accordance with the subject invention, time delays are measured between successive strokes of a keyboard as the individual enters his name. A timing vector, which is constructed from the time delays, is statistically compared with a stored timing vector derived from the authorized individual. If the timing vectors are statistically similar, the individual will be permitted access to the resource.

Abstract: A remote controlled switching apparatus for controlling the operation of a device having a plurality of modes of operation. In the apparatus there is provided a first switch assembly responsive to a positive potential for causing the apparatus to operate in a first mode of operation and a second switch assembly responsive to a negative potential for causing the apparatus to operate in a second mode of operation irrespective of the mode of operation in which the device is then currently operating. Automatic and manually controlled switch assemblies selectively provide the positive and negative potentials. Status indicators provide an indication of the current mode of operation of the device being controlled.

Abstract: Alarm producing apparatus for safeguarding a container carried by a messenger including a time countdown system and a status detection system assuring that container and messenger remain together. Countdown time is set sufficiently to allow normal delivery of container by messenger. Smoke, sound and/or visual signals are triggered by separating container from messenger or by excess time lapse occurring during delivery of container by messenger.

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: A composite locking device comprises a case frame adapted to be connected to the inside of a door and a lock lever within the case frame. The lock lever is capable of lateral movement and has a first end which extends through the opening in the case frame to be received in a recess in a door jamb, and a second end within the case frame. The case frame includes a rotatable disk which is adapted to receive a key for laterally displacing the lock lever. A lockhead is fastened adjacent to the disk so that the key passes therethrough before it is received by the rotatable disk. The lockhead includes a power switch which is activated by insertion of the key, the power switch in turn activating a code switch. The code switch activates an electromagnet. A lock bolt is provided in the case frame which engages the lock lever. When the electromagnet is activated, it attracts the lock bolt away from the lock lever thus permitting lateral displacement of the lock lever by the key without activating an alarm.

Abstract: A secure keyboard input terminal is disclosed in which a secret user identification code number or other confidential data sequence formed from a set of alpha-numeric characters (for example, the ten numerical digits 0 through 9) may be input secretly by a user, the terminal itself comprising (a) a plurality of input keys (in the case of one illustrated apparatus, 10 separate keys), (b) a corresponding plurality of character displays adapted for displaying said characters and (c) electronic circuitry for (1) apparently randomly associating selected ones of said character set to respective individual keys, (2) displaying to the user the character thus associated with each key and (3) translating a signal representing the actuation of a particular key by the user into a signal representing the particular character then associated with that key.

Abstract: A slide switch is movable in the direction of oscillation of the reed of a magnetic circuit. A resilient arm is attached at one of its ends to the switch. The slide switch drives the arm in the direction of the oscillation of the reed, the motion of the arm being in a plane parallel to the oscillation path of the reed but removed from it. A ramp is located adjacent the opposite end of the arm and intersects the plane of the oscillation path of the reed, one end of the ramp engaging the opposite arm end at its equilibrium position and the other end of the ramp extending well into the plane of the oscillation path of the reed.

Abstract: The anti-theft control system includes a sending module (A) for sending encoded signals on a power line (12) of a vehicle power supply (B). The sending module (A) includes a keyboard (52) on which an authorized user enters his code. If the proper code is entered, a digital encoder (40) produces a preselected encoded signal which is imposed on the power signal by an interface circuit (60). The anti-theft control system further includes a receiving module (C) which receives encoded signals from the power line. The receiving module includes a detector (70) for separating encoded signals from the power signal and a decoder (80) for comparing the received encoded signal with the preselected encoded signal. If the decoder (80) determines that the preselected encoded signal has been received, it enables an ignition control circuit (90) to pass electric power from the vehicle ignition key switch (20) to the vehicle ignition (22).

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: A combination lock of the dial operated tumbler wheel type comprising lock mechanism components including a fence lever and rotatable members to be rotatably positioned responsive to rotation of a dial, the rotatable members including peripherally gated tumbler wheels and a drive cam driven from the dial, and electro-optical light sensing and electrical signalling means for producing sensible indications at a remote monitoring station signifying movement of components of the combination lock mechanism. This means comprises a marking having optically distinctive reflectivity properties on a component of the lock mechanism such as the driving cam and/or a tumbler wheel and/or the fence lever and optical sensor means positioned to receive light from the optically distinctive marking electrical signal signifying movement of the optically distinctive marking.

Abstract: An electronic key (A) includes an electrical plug (10) which is connected with the power, and ground, and output terminals of an encoder (20). An electrical jack (30) is adapted to receive the electronic key plug (10) to supply ground and power thereto and receive an encoded signal therefrom. A decoder (50) is connected with the jack to receive the encoded signal and produce an enable signal if the encoded signal has a preselected code. The enable signal is extended by a first latch (54) to an indefinite duration and the extended enable signal closes an enabling switch (56) and disables an alarm control (80). The enabling switch (56) allows an automotive ignition key (60) to operate the automotive ignition (62). When the enabling switch (56) and the ignition key switch (60) are closed, the first latch is reset and a second latch (68) is enabled to continue producing the enable signal of indefinite duration.

Abstract: An electronic sequential combination locking device comprising a main switch to which a timer circuit is connected. The timer circuit is activated by the main switch to provide a timer output signal after a predetermined time lapse. An electronic switch means is connected to receive the timer output signal. An alarm is connected to the electronic switch means and is operable by the presence of the timer output signal. A combination lock circuit having a plurality of manually actionable switches is operable in a predetermined sequence to activate a supply switch and disable the electronic switch. The supply switch provides a supply to an operable means.

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 combination 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.