US3613064A - Alarm control - Google Patents

Alarm control Download PDF

Info

Publication number
US3613064A
US3613064A US814537A US3613064DA US3613064A US 3613064 A US3613064 A US 3613064A US 814537 A US814537 A US 814537A US 3613064D A US3613064D A US 3613064DA US 3613064 A US3613064 A US 3613064A
Authority
US
United States
Prior art keywords
relay
flop
flip
alarm
circuit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US814537A
Inventor
Charles H Peterson
Curtiss C Krueger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Defensive Instruments Inc
Original Assignee
Defensive Instruments Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Defensive Instruments Inc filed Critical Defensive Instruments Inc
Application granted granted Critical
Publication of US3613064A publication Critical patent/US3613064A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B19/00Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow

Definitions

  • Plttsburgh ABSTRACT An alarm control system has an internal receiver module and an internal ultrasonic intruder detector module [54] ALARM CONTROL connected to one input channel of a bistable flip-flophAn intemal heat sensor fire detector is connected to another Input 18 Claims, 2 Drawing Figs. A
  • Remote Inputs are connectable to either input chan- U.S. nel Inputs in the first channel cause the to change to 340/213 340/326, 340/371, 340/420 the alarm state and to operate a relay driver which partially ll Int. Cl 7/00, com letes AC outlet relays and remote output relays and G08b13/0O which starts an adjustable delay timer to operate a second Field 01 swrch relay driver for completing a horn relay and for par. 420, 326, 213-1; 317/137 tially completing a circuit to a reset delay device.
  • a function 1 selector selectively grounds one or more of the output relays [56] Reirences cued preparatory to operation of the flip-flop and relay drivers so UNITED STATES PATENTS that the circuits are ready to operate the appropriate output 2,703,367 3/1955 Florman 340/371 X when the flip-flop is biased into an alarm state.
  • the second 3,200,393 3/1965 340/420 X channel is connected directly to the second relay driver and to 3,212,079 1 5 340/213.] the function selector for overriding the function selector for 3,257,653 1966 340/224 grounding all relay coils so that all signals operate when an ex 3,260,991 7/1966 Laakmann 340/258 UX tremely hazardous condition such as fire is sensed by second 3,380,044 4/1968 Mordwinkin 340/258 channel sensors.
  • Timing circuits heretofore available have experienced difficulty in providing an adjustable range ratio as high as the present circuit while maintaining a linear time scale on the time delay adjustment control.
  • Time delay controls such as in the present invention in which the time delay circuit resets itself instantaneously and can immediately resume the timing cycle with a very small amount of error have heretofore been unavailable.
  • Multiple function selection switches of conventional design require complex multiple-pole selector switches.
  • the present invention avoids the use of such devices by an unusual arrangement of diodes and a single pole switch.
  • the present apparatus overcomes that possibility by adding a time delay to the reset equipment so that an alarm output will occur for at least 5 seconds for any trigger caused by any sensor before the equipment is reset to a no alarm condition.
  • the alarm control module receives signals from a multitude of internal or remotely located sensors and provides logic and timing functions so that an appropriate alarm indicating device is actuated.
  • a horn that produces at least IOO-db. sound pressure level is used as an internal alarm indicating device.
  • Two outputs from the system are used for remotely located alarm indicating devices.
  • One output is a relay controlled outlet providing 1 17 volts AC at 600 watts.
  • the second output is a set of normally open or normally closed dry relay contacts which carry current up to 1 amp.
  • Various combinations of the alarm module outputs can be selected by the switching circuitry incorporated in the equipment.
  • the function selector enables the output or combination of outputs as selected. When an alarm trigger signal occurs, the outputs that are enabled will then be actuated; the outputs remain actuated until the system is reset or until a complete loss of power occurs.
  • Triggering input A causes all logic and timing functions to act normally and causes the output reaction to be that established by the function selector.
  • Input B referred to as the instant alarm input, bypasses all timing functions and function selection; a trigger at input 8 causes all outputs to be actuated instantaneously regardless of control positions.
  • Provisions are made in the system to accept three kinds of internal modules or sensors, which are a heat sensor, an ultrasonic intruder detector module, and a radiofrequency receiver module. All low-voltage inputs and outputs of the system are located on terminal strips mounted on the rear of the modules. ll7-Volt AC 60-cycle power or internal rechargeable battery power operates the system which is always ready irrespective of external power distribution systems or switches.
  • the internal ultrasonic intruder detection system is connected to the first triggering input channel to employ all logic and timing functions.
  • a system is used such as described in copending application Ultrasonic Detection System, filed Mar. 10, 1969, by C. H. Peterson'and C. C. Krueger, is used.
  • An internal radio receiver is connected to the same triggering input channel as the ultrasonic intruder detection system. Alternatively, the receiver may be connected to the immediate response input channel. When the receiver is keyed by radiofrequency within its sensitivity, logic and timing functions of the control circuit are set into operation.
  • One or more radiofrequency transmitters may be located at convenient locations remote from the alarm control.
  • the transmitters may be operated by buttons depressed by persons who wish to set off the alarm control, or the transmitters may be controlled by remote perimeter metering devices such as black light photoelectric cells, contact or broken circuit sensitive devices.
  • the transmitters may be connected to heat or flame sensitive devices to provide an alarm system with remote wireless fire detection stations.
  • Transmitters may be used with any automatic monitoring systems.
  • Personally carried transmitters may be connected to battery operated health condition monitors.
  • Each input circuit is provided with external connection jacks terminals so that any external detector may be wired to the alarm control and may activate its immediate response total signal mode or its programmed response mode. Any condition monitor may be connected to either input.
  • the alarm system may be wired to remote panic button stations or to any condition monitor.
  • One objective of this invention is the provision of alarm control systems with function selector means for individually and collectively enabling signaling means to respond to intruders, fire or other energy producing inputs.
  • This invention has as another objective the provision of alarm control systems which have first and second input channels from sensing means so that sensing means on one channel may operate through a logic control system to control the operation of signaling devices and so that energy sensing means on a second channel may directly operate the signaling devices, bypassing the logic control circuit.
  • Another objective of this invention is the provision of alarm control apparatus with bistable flip-flop circuits for remaining in an alarm state until intentionally reset.
  • Another objective of this invention is the provision of alarm control systems having time delay means for operation of localized signals in response to circuit tripping and for immediate operation of remote signals in response to the same tripping and for selection of local and remote signals.
  • a further objective of this invention is the provision of time delay reset means so that alarm control apparatus may not be deenergized before it has responded to a triggering for a predetermined time.
  • FIG. 1 is a schematic block diagram of the interrelationship of elements of the invention.
  • FIG. 2 is a schematic diagram of the electrical components of a preferred embodiment for carrying out the objectives of this invention.
  • FIG. I A reference to the functional block diagram FIG. I will aid in understanding the following description.
  • Multiple numbers, for example l-20 refer to elements having those and intermediate numbers in FIG. 2.
  • the equipment is comprised of major circuit sections, which are identified in the drawings as flip-flop 10-20, AC outlet relay 6A, remote output relay 7A, adjustable delay timer 22-30, horn relay 36A, function selector 50, input A, input B, reset delay 43-45, and power supply 51-69.
  • the power supply is connected to all other sections; therefore, for clarity in understanding the interrelation of other sections, the power supply connections are not shown in the schematic FIG. 1.
  • FLIP-FLOP Every input to the system is first fed to the bistable flip-flop 10-20; the reset command signal is also fed to this stage.
  • This logic element has two stable states. An alarm trigger signal from any input causes the flip-flop to set and remain in the alarm state even though the alarm trigger may be momentary. The flip-flop remains in the alarmed state until a reset pulse occurs and causes the flip-flop to assume its original no alarm state. The remainder of the system therefore, reads out the state of the flip-flop and acts accordingly. Both outputs of this logic element are used to drive the circuitry that follows.
  • a transistor switch 9 acts as the relay coil driver.
  • a relay driver transistor 9 switches on and connects one side of the AC outlet relay coil 6A to 8+. The other side of the relay coil is connected to the function selector 50. If the function selector has not been set to enable this relay, an open circuit is presented to the relay, and, the relay is not energized. If the function selector has enabled this relay, the relay circuit completes causing the relay to be energized.
  • REMOTE OUTPUT RELAY One side of the remote output relay coil 7A is connected to the same relay driver transistor 9 as the AC outlet relay 6A.
  • the remote output relay functions identically to the relay described in the above paragraph; its coil current is enabled or disabled by the function selector 50.
  • a form C relay contact arrangement 78 (FIG. 2) is used to provide both a normally open and normally closed set of relay contact outputs.
  • An adjustable delay timer 22-30 is actuated by the other output of the flip-flop 10-20.
  • a variable potentiometer makes the time delay adjustable from a small fraction of a second to at least 10 seconds.
  • the output of the timer remains in the no alarm state until the time period, as set by the control, is reached. At that time the output of the timer switches to the alarm state.
  • the delayed alarm signal is fed to the horn relay 36A only; therefore, the timer is referred to as the Horn Time Delay Control.
  • HORN RELAY-FLASHER DC current to the horn is switched on and off by the horn relay contacts.
  • the horn relay 36A is energized.
  • An electronic horn relay circuit 32-41 associated with the horn relay causes the relay current to be interrupted at time intervals and durations established by the electronic circuit.
  • the acoustical output of the horn therefore, is not continuous but is a beeping sound.
  • the function selector has not been set to enable the horn relay, no current flows through the horn relay coil, and no horn output occurs.
  • the function selector switch 50 has four positions, which are: AC outlet only; AC and horn; AC, horn, and remote output; and remote output only.
  • a diode matrix in conjunction with a single pole rotary switch are used to enable the combinations of outputs.
  • INPUT A Input A of the flip-flop 10-20 is a normally open input. When any alarm sensor is connected to this input and exhibits a close circuit, the flip-flop is set in the alarmed state. Even if the input reverts back to an open circuit condition almost instantaneously, the flip-flop remains in the alarm state. Because Input A is a normally open circuit configuration, an infinite number of alarm sensors can be connected in parallel to this input. If any one of these alarm sensor circuits close, the alarm trigger and timing functions commence immediately. Maximum current flow in this circuit is 2 milliamperes.
  • INPUT B Input B the instant alarm mode input, incorporates a diode matrix circuit to actuate the flip-flop, horn relay driver, and function selector simultaneously.
  • the multiple actuation causes the flip-flop to be set, bypasses the horn time delay circuit, and enables all relay output functions, regardless of the setting of the function selector switch.
  • Input B As long as Input B remains a closed circuit all functions are actuated instantaneously. If lnput Circuit B reverts to an open circuit at a later time, the output functions that are not selected or enabled by the function selector switch, are shut off, and only those functions selected by the selector switch remain in alarm condition.
  • POWER SUPPLY I l7-volt AC power is converted to l8-volt DC in the power supply section 51-69.
  • DC power is supplied to all active sections of circuitry as well as to the trickle charging circuit for the nickel cadmium standby battery pack.
  • a solid state switching circuit automatically connects the battery into the circuit in the event of AC power loss. In the latter mode of operation there is a 12-volt nominal Brivoltage. All logic and timing functions operate identically at either a standby l2-volt voltage or the normal l8-volt voltage.
  • a pilot lump indicates when AC power is applied to the equipment.
  • a dark pilot light indicates a loss of AC power or that the AC power switch on the rear of the module is in the off position.
  • the power supply also supplies DC power to the internal RF receiver module and the internal ultrasonic intruder detector module. Since the internal heat sensor and the remote accessories connected to the remote input terminals are'all passive devices, they do not require power. Under no alarm conditions, the power consumption is very minimal, allowing at least 8 hours of standby power operation. When the system is in the alarmed condition, the power consumption is dependent on the number of functions that are enabled. If the horn is actuated in standby battery mode of operation, 5 to 30 minutes of horn operation is available, depending on the duration of AC power loss before the horn was actuated. When a standby battery pack has been completely discharged, 16 hours of AC operation is required to fully recharge the bat tery.
  • FIG. 2 components utilized for the circuitry herein described are designated by numbers. Letter designations are used to indicate connecting points to conventional associated circuitry or electronic components, which, because they are conventional are not described in full detail.
  • the detailed circuit description of FIG. 2 fully describes all parts associated with the alarm control module.
  • the total system is a completely effective self-contained system without the use of accessory equipment.
  • accessory alarm sensors or remote alarm indicating systems can be connected to this system to further improve its effectiveness and versatility.
  • ALARM VOLTAGE INPUT Terminal R connects to the alarm output of the ultrasonic intruder detector module.
  • the output of that module is a DC voltage proportional to the amount of motion that the detector senses.
  • Resistors 72 and 71 and transistor 73 comprise a DC threshold transistor switch. When a certain DC level has been exceeded at terminal R, transistor 73 will switch on, causing a low-resistance condition between collector and emitter connections of transistor 73. This DC threshold switching action also causes a low resistance to ground condition at the input of the flip-flop circuit.
  • Resistor M in conjunction with resistor 13 determine the voltage threshold characteristics of transistor 15.
  • Resistor l7 and resistor 18 in conjunction with resistor 16 determine the voltage threshold characteristics of transistor 19.
  • Resistor 20 serves as the collector mode resistor for transistor 19. By intentionally making the resistance of resistor 20 much larger than that of resistors 10, and I1, transistor 19 saturates more easily than transistor 15. It is for this reason that transistor 19 is always the on transistor in the normal state. Since transistors 15 and 19 are cross coupled, the states of each are always opposite each other. Therefore, one or the other is on, and one or the other is off. This action causes current to flow always through diode 21.
  • the voltage drop across diode 21 remains essentially constant and serves as back-bias to transistors 15 and 1 .9, ensuring that the off transistor is definitely ofl".
  • the flip-flop shown herein by way of example is designed for circuit closing alarm sensors, conventional modification makes the flip-flop suitable for use with circuit opening alarm sensors.
  • RELAY 6 AND RELAY 7 Relay contacts 68 and 7B are shown in the deenergized state.
  • contacts 68 close, applying l20-volt AC power to AC outlet IJ.
  • contacts 78 switch from position 1 to position 2, causing output terminals E and F to change to an open circuit and output terminals G and H to present a closed circuit.
  • Remote alarm control apparatus connected to either of those output terminal pairs sense the change of state and actuate their particular alarm modes.
  • Diode 8 protects transistor 9 from any inductive kickback surges from relay coils 6A or 7A.
  • HORN DELAY TIMER It is normally very difficult to design a circuit with a time delay range ratio as high as the circuit designed in this system and to maintain a linear time scale on the time delay adjustment control.
  • the time delay circuit of the present invention resets itself instantaneously and can immediately resume the same timing cycle with a very small amount of error.
  • Circuit components 22 through 30 serve as the adjustable delay timer.
  • Normally capacitor 24 is grounded through resistor 23, diode 22, and flip-flop transistor 19.
  • Adjustable resistor 30 and resistors 29 and 28 serve as a variable voltage bias network in the emitter circuit of transistor 26.
  • Transistor 26 is normally off, since the emitter voltage is higher than the base voltage in the no alarm state.
  • transistor 19 shuts off, causing diode 22 to reverse bias, thereby ungrounding capacitor 24, which begins to charge towards B+ through resistor 25.
  • transistor 26 turns on. If variable resistor 30 is set at maximum resistance, the greatest amount of voltage exists at the emitter of transistor 26. That condition establishes the maximum time delay as established by the RC product of resistor 25 and capacitor 24. At that time, capacitor 24 will have accumulated enough charge so that its potential is higher than the emitter potential, and transistor 26 turns on. The delayed alarm trigger signal, therefore, is located across resistor 27. The time delay can be varied between minimum and maximum limits established by the variation of emitter potential on transistor 26.
  • HORN RELAY CIRCUIT Elements 32 through 41 comprise the horn relay circuit.
  • Resistor 32 establishes the base current flow for transistor 33.
  • transistor 33 When an alarm signal exists at the output of the adjustable horn delay timer circuit, transistor 33 is turned on causing the collector potential of transistor 33 to raise from zero to 13+ voltage.
  • Diode 34 couples this plus voltage to the horn flashing circuit.
  • the simple electronic circuit used in conjunction with the horn relay coil causes a flasher action.
  • the flashing rate and flashing duration is easily adjustable and can be varied over a wide range. The power consumption is very minimal when compared to standard flasher devices that typically work on a thermal heating effect of a bimetallic contact arrangement.
  • Transistor 38, resistors 37 and 40, capacitor 39 and unijunction transistor 41 comprise an electronic multivibrator circuit, causing relay coil 36A to be energized and deenergized at a predetermined rate.
  • Relay contacts 368 close and open, respectively causing horn 74 to be energized and deenergized.
  • RC product of resistor 40 and capacitor 39 determine the on time of the multivibrator circuit.
  • Diode 35 protects transistor 38 from inductive kickback voltages from relay coil 36A.
  • the relay circuit can be energized only when it is connected to ground. This again depends on the position of function selector switch 50.
  • FUNCTION SELECTOR Function selection used in this apparatus eliminates the use of a complex multiple-pole selector switch.
  • the combination of diodes and a one-pole switch yields an extremely simple solution to a typically difficult problem.
  • Function selector switch 50 enables relays 6A, 7A and 36A in the following manner. In position 1 relay 6A is grounded, and relays 7A and 36A are ungrounded due to diode 47 being back-biased. In position 2 relay 36A grounds directly, relay 6A grounds through diode 47 being forward biased, and relay 7A remains ungrounded due to diode 48 being back-biased.
  • relays 6A, 7A and 36A are grounded due to diodes 47, 48 and 49 forward conducting.
  • relay 7A grounds directly, and relays 6A and 36A are ungrounded due to diode 49 being backbiascd.
  • the function selector therefore, allows various combinations of events to occur when the alarm system has been triggered.
  • INSTANT ALARM CIRCUIT Diode matrixes of the function switch and Input B produce an all-function enabling override regardless of switch position.
  • This second logic loop forms the basis for many of the unique features and functions that are displayed in this equipments design.
  • This section of circuitry also overrides the adjustable time delay circuit function. Circuit components 31, 2, 3 and 4 cause an overriding chain of events to occur. Resistor 31 maintains input terminal A at a positive potential, back biasing diodes l, 2 and 4 to maintain an out of circuit condition. When a closed circuit exists between terminals A and B or terminals N and O, voltage at A drops to zero, causing diodes l, 2 and 4 to conduct.
  • relays 6A, 7A and 36A are effectively grounded.
  • the conduction of diode 1 causes the flip-flop to be triggered to the alarmed state. Therefore, relay 6A and 7A are instantly energized, regardless of the position of function switch 50.
  • the conduction of diode 2 causes the emitter potential of transistor 26 to be dropped to close to zero volts, which supercedes any preset timing delay voltage in the circuit; the horn relay circuit is energized instantaneously.
  • Relay 36A also is energized instantaneously due to the fact that it grounds through diode 4, regardless of the position of function switch 50. The instant alarm input, therefore,
  • RESET CIRCUIT The present method of reset timing does not allow the system to become completely disarmed. An alarm output will always occur for at least 5 seconds for any trigger caused by any sensor that is connected to the input of the system. There is no need to incorporate keylock switches and other such devices in order to provide a secure system.
  • the flip-flop remains in the alarmed state irregardless of which input circuit has triggered it; the trigger can be of a momentary or continuous nature depending on the source.
  • a means of resetting the flip-flop must be provided. Two conditions must exist before the flip-flop can be reset; a specific time interval must exist after the horn circuit has been energized, and all input circuits must be cleared. Components 43, 44 and 45 act as a timing pulse circuit, determining the time interval before the flip-flop can be reset. When the horn circuit has been energized, capacitor 44, begins to charge through resistor 43. The voltage versus time relationship established by this RC product determines the amount of time delay. Unijunction transistor 45 does not fire until reset switch 46 has been depressed.
  • AC PRIMARY CIRCUIT Reference 51 connects to -volt AC 60-cycle power source; the third wire represents the equipment ground return.
  • Switch 53 acts as the AC power on and off switch.
  • Fuse 54 will open circuit due to fault currents in either transformer 58 of AC outlet IJ. This protects all internal wiring as well as relay contacts 68 against an over current situation.
  • Resistors 55, 56, and neon lamp 57 are used to indicate when AC power is applied to the electronic circuitry. With l20-volt AC applied across the primary of transformer 58A, a voltage stepdown to 12 volts AC occurs at secondary 588. Secondary AC voltage is rectified by diodes 59, 60, 61 and 62 to produce a DC output voltage of approximately 19 volts.
  • Capacitors 63, 64 and 65 filter out AC ripple from the rectification process to produce an acceptable pure DC voltage, referred to as B+ voltage.
  • B+ voltage is fed to all active circuits contained in the alarm control module and is fed to terminals Q and S to supply power to auxiliary equipments.
  • INTERNAL STANDBY POWER Elements 66 through 69 comprise the internal standby battery power system.
  • Switch 68 connects or disconnects battery 69 from the circuitry. It also connects or disconnects the B+ voltage to terminals which feed DC power to auxiliary equipment.
  • Battery 69 is a nickel cadmium battery capable of being charged and discharged many times. With switch 68 on, resistor 67 determines the trickle charge current. Diode 66 is back-biased when AC power is applied; therefore, the rectified AC supplies all circuit power, and battery 69 is effectively disconnected from the circuit and is in a trickle charging mode. When AC power fails, B+ voltage begins to drop.
  • diode 66 When it drops 0.6 volts below the battery voltage, diode 66 conducts and automatically connects battery 69 to the B+ line, allowing the battery to supply uninterrupted power to the electronic circuitry.
  • the intentional voltage difference between the two sources of DC power allows the standby power switchover arrangement to be utilized.
  • DC ClRCUlT TO ULTRASONIC MODULE Switch 70 when closed applies the battery voltage to terminal P to enable and supply standby power to the ultrasonic intruder detector module.
  • switch 70 When switch 70 is opened or in the off position, the ultrasonic intruder detector module is disabled or disarm'ed and, therefore, is not capable of triggering the alarm control module, irregardless of the positions of switch 68 or 53.
  • Switches 53 and 68 being in the off position, disarms the complete system. All alarm inputs are armed when either switch 53 or switch 68 in on.
  • ljAlarm control apparatus comprising:
  • control circuit means connected to the energy sensing input means
  • function selector means connected to each signalling means separately from the control circuit means for individually and I collectively enabling the signalling means for response to the energy sensing means and control means.
  • the energy sensing input means comprises first and second energy sensing input means, and wherein the secondenergy sensing input means is connected to the signalling means, whereby the signalling means operates in response to the control circuit means in response to energy sensing by the first input means, and whereby the signalling means directly operate in response to energy sensing by the second input means.
  • the alarm control apparatus of claim 2 wherein the energy sensing input means comprises first and second energy sensing input means, and wherein the second input means is connected to the function selector means for selectively enabling the signalling means in responseto energy sensing by the second input means.
  • first energy sensing input means comprises an ultrasonic intruder detector means and wherein the second energy sensing input means comprises heat sensor means.
  • the alarm control apparatus of claim 4 wherein the first energy sensing means additionally comprises a radiofrequency receiver and connection means for remote accessories, and wherein the second input means further comprises second connections for remote accessories.
  • control circuit comprises a bistable flip-flop circuit connected to the energy sensing input means.
  • control circuit means further comprises relay driver means connected to the flip-flop means and signal relay means connected to the relay driver means for controlling the signalling means.
  • control circuit means further comprises adjustable delayed timer means interposed between the flip-flop circuit and the relay driver means, a reset switch means connected to the flip-flop means and reset delay means connected between the relay driver means and the reset switch means for delaying resetting of flip-flop to a no alarm condition.
  • control circuit means include time delay apparatus comprising a first normally on transistor having an emitter connected to ground, a diode connected to a collector of the first transistor, a capacitor connected between the diode and ground, a first resistor connected between the capacitor and a source of DC power whereby the capacitor is charged through the first resistor when the first transistor is 01?, a second transistor having a base connected to the capacitor and having an emitter-collector circuit connected to a source of power and to an alarm response circuit for operating the alarm response circuit when the second transistor is conductive, an emitter of the second transistor being connected through second resistor to a source of power and through a potentiometer to ground whereby the emitter is held at a voltage higher than the'base when the capacitor is grounded through the first transistor, and whereby adjusting the potentiometer controls the time required after the first transistor has been turned off for the capacitor to charge sufiiciently toturn the second transistor on thereby completing circuit means b etween the power source and a
  • the function sel ectbr means includes a function selector switch for selectively connecting a single movable pole to first,second and third connecting lines which are connected to respective signalling means contacts comprising: a movable pole, a first contact connected to a first line, a second contact connected'to the second line and connected via a unidirectional element to the first line, a third contact connected to the 'thirdline, and a fourth contact connected to the third contact via a unidirectional element and connected to the second contact via a unidirectional element, whereby thefirst contact provides a pole contact for the firstv line, the second contact provides a pole contact for first and second lines, the third contact provides ground contact for the third line and thefourth contact provides pole contact for first, second and third lines.
  • control circuit means includes a reset time delay comprising a unijunction transistor connected to a source of power and to an alarm reset switch which is in turn connected to a flip-flop circuit, a unijunction transistor having a biasing connection connected to a capacitor which is grounded on one side thereof and which is connected through a resistance to the output of a time delay relay, whereby closing the alarm reset switch after the time delay relay has become energized charges the capacitor through the resistance to a potential required to make the unijunction transistor conductive enabling resetting of the control circuit means after a time delay.
  • An alarm control system comprising first and secondenergy sensing input means,
  • controlcircuit means connected to the energy sensing input means
  • signalling means connected to the control circuit means and to the second energy sensing means for controlled response to the energy sensing of the first input means and for direct response to energy sensing by the second input means
  • function selector means connected to the signalling means separately from the control circuit means for severally enabling the signalling means for response to the sensing means and control means
  • control circuit means comprises a bistable flip-flop connected to the first and second energy sensing input means
  • first and second relay drivers respectively connected to the flip-flop and to the adjustable delay timer
  • a reset delay and reset switch connected between the second relay driver and the flip-flop for resetting the flipflop after a time delay
  • the function selector is connected to the AC outlet relay, to the remote output relay, and to the horn relay, whereby the function selector may select either AC outlet control, AC outlet control and horn operation, AC outlet control, horn operation and remote output, or remote output,
  • the second energy sensing input means is connected to the flip-flop, to the second relay driver and to the function selector for overriding the function selector and operating all of the signalling means in response to the energy sensing by the second input means.
  • a self-contained alarm system for sensing the presence of intruders or of excessive heat and for responding by a selfcontained alarm device, comprising a power source having a cord and plug for connection to a conventional ll-volt AC input source and having transformer and rectifier means for producing a relatively low DC voltage from the AC input voltage, multiple signal means connected to the power source, an ultrasonic intruder sensor connected to the power source, a fire sensor having a heat sensitive switch connected to the power source, a radiofrequency sensor, an alarm control circuit connected to the fire sensor, to the ultrasonic intruder sensor and to the radiofrequency sensor and to the signal means and function selector means connected to the signalling means independently of the control circuit, for operating a signal means in response to an input from the sensors.
  • the method of controlling alarms comprising connecting condition sensors to two input channels, connecting the input channels to a bistable flip-flop circuit, changing state of the bistable flip-flop in response to condition sensing by one of the sensors, connecting a power source to a first set of relay coils in response to changing of state of the flip-flop, beginning operation of a time delay circuit in response to changing of state of the flip-flop, connecting the power source to a relay for operating the local signal in response to completion of the time delay circuit and selectively grounding any or all of the relays preparatory to the changing of state of the flip-flop device, whereby selected relays are enabled for causing operation of relay switches in response to changing of state of the flip-flop device.
  • the beginning operation of a time delay circuit comprises the sequential steps of biasing a first transistor off by providing an emitter potential higher than a base potential, shorting a capacitor connected to the transistor base, unshorting the capacitor upon a start signal, slowly charging the capacitor to a potential above emitter potential, thereby causing the transistor to turn on completing an alarm circuit and controlling time delay by varying emitter potential.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)

Abstract

An alarm control system has an internal receiver module and an internal ultrasonic intruder detector module connected to one input channel of a bistable flip-flop. An internal heat sensor fire detector is connected to another input channel. Remote inputs are connectable to either input channel. Inputs in the first channel cause the flip-flop to change to the alarm state and to operate a relay driver which partially completes AC outlet relays and remote output relays and which starts an adjustable delay timer to operate a second relay driver for partially completing a horn relay and for partially completing a circuit to a reset delay device. A function selector selectively grounds one or more of the output relays preparatory to operation of the flip-flop and relay drivers so that the circuits are ready to operate the appropriate output when the flip-flop is biased into an alarm state. The second channel is connected directly to the second relay driver and to the function selector for overriding the function selector for grounding all relay coils so that all signals operate when an extremely hazardous condition such as fire is sensed by second channel sensors.

Description

ass sR 39 27M? [72] Inventors Charles H. Peterson; 3,401,234 9/1968 Heald 340/213 X Kruger bow of San Dlego Primary Examiner-John W. Caldwell Assistant Examiner-Perry Palan [21] Appl. No. 814,537 [22] Filed Apr. 9, 1969 Attorney-Lrttlepage, Quaintance, Wray & Alsenberg [45] Patented Oct. 12, 1971 [73] Assignee Defensive Instruments,1nc.
Plttsburgh ABSTRACT: An alarm control system has an internal receiver module and an internal ultrasonic intruder detector module [54] ALARM CONTROL connected to one input channel of a bistable flip-flophAn intemal heat sensor fire detector is connected to another Input 18 Claims, 2 Drawing Figs. A
channel. Remote Inputs are connectable to either input chan- U.S. nel Inputs in the first channel cause the to change to 340/213 340/326, 340/371, 340/420 the alarm state and to operate a relay driver which partially ll Int. Cl 7/00, com letes AC outlet relays and remote output relays and G08b13/0O which starts an adjustable delay timer to operate a second Field 01 swrch relay driver for completing a horn relay and for par. 420, 326, 213-1; 317/137 tially completing a circuit to a reset delay device. A function 1 selector selectively grounds one or more of the output relays [56] Reirences cued preparatory to operation of the flip-flop and relay drivers so UNITED STATES PATENTS that the circuits are ready to operate the appropriate output 2,703,367 3/1955 Florman 340/371 X when the flip-flop is biased into an alarm state. The second 3,200,393 3/1965 340/420 X channel is connected directly to the second relay driver and to 3,212,079 1 5 340/213.] the function selector for overriding the function selector for 3,257,653 1966 340/224 grounding all relay coils so that all signals operate when an ex 3,260,991 7/1966 Laakmann 340/258 UX tremely hazardous condition such as fire is sensed by second 3,380,044 4/1968 Mordwinkin 340/258 channel sensors.
. [9 REMOTE 6A REMOTE INPUT RELAY AC OUTLET AccEssORIEs DRIVER RELAY PRE-SET 57A INTERNAL [IO- REMOTE 2335 RECEIVER OUTLET A RF MODULE FL'P FLOP RELAY K-L-M 5 H REsET MOVING INTERNAL 46 OBJECT ULTRASONIC W DETECTION MODULE r43 P-Q-R ADJUSTABLE RESET DELAY INTERNAL DELAY 5 SEC. HEAT l HEAT sENsoR 32-4l REMOTE ital J RELAY HORN CE 0 5 AC RIE INSTANT DRIVER RELAY "7 VAC ENABLE ALL I AC POWER FUNCTIONS FUNC'HON 2 Ac 8 HORN |NPUT SELECTOR 3-AC, HORN, REA
4-REMOTE PAIENTEBIIU I2 I971 REMOTE ACCESSORIES REMOTE TRANSMTTTER MOVING OBJECT DETECTION HEAT REMOTE ACCESSORIES ll? VAC POWER INPUT SHEET 16F 2 [9 6A REMOTE RELAY AC OUTLET INPUT DRIvER RELAY PRE-sET INTERNAL [IO-2O REMOTE REcEIvER r OUTLET A RF MODULE RELAY FLIP-FL0P \KLM T RESET INTERNAL J ULTRAsONIc 1 SW MODULE f 30 43 45 P-Q-R II ADJUSTABLE RESET DELAY INTERNAL DELAY TIMER 5 SEC.
HEAT A sENsOR Luv 36A I1 REMOTE RELA O N INPUT Y 7 H R DRIVER RELAY INsTANT [SI-69 I [50 ENABLE ALL I AC POWER FUNCTIONS FUNCTION 2* Ac 8 HORN J SUPPLY SELECTOR 3AC,AHORN,REM
4-REMOTE F/G. I INVENTORS C. H. PETERSON CURTISS C. KRUEGER May,
ALARM CONTROL BACKGROUND OF THE INVENTION The need for improved fire and burglar alarms is well recognized. l-leretofore, compact plug-in equipment, which requires no special installation and which is contained in a single small self-sufficient package, has been unavailable. Moreover, combined burglar alarm and fire alarm control equipment which effects a time delay control for the burglar alarm and immediate response for fire alarms is not known The present apparatus accepts radio signals, detects motion and senses heat and controls an alarm response in a completely effective selfcontained system without the use of accessory equipment. However, accessory alarm sensors or remote alarm indicating systems can be connected to the present system to further extend its effectiveness and versatility. The present system, in response to remote radio transmitters or remote electrically connected devices, responds with time delayed local signals and the completing of power connections for remote signalling devices.
Most systems of conventional design connect relay control circuits directly to various alarm sensors. Because it is desirable to provide a latching function so that once the alarm is actuated it remains actuated until intentionally reset, many of the latching relays that are commercially available are very complex mechanically and are highly unreliable.
Timing circuits heretofore available have experienced difficulty in providing an adjustable range ratio as high as the present circuit while maintaining a linear time scale on the time delay adjustment control. Time delay controls such as in the present invention in which the time delay circuit resets itself instantaneously and can immediately resume the timing cycle with a very small amount of error have heretofore been unavailable.
Multiple function selection switches of conventional design require complex multiple-pole selector switches. The present invention avoids the use of such devices by an unusual arrangement of diodes and a single pole switch.
One very real danger in the successful use of intruder alarms, particularly, is the danger that the intruder will disconnect the alarm or disable the alarm such as by depressing the reset button and resetting the equipment to a no alarm condition. The present apparatus overcomes that possibility by adding a time delay to the reset equipment so that an alarm output will occur for at least 5 seconds for any trigger caused by any sensor before the equipment is reset to a no alarm condition.
SUMMARY OF THE INVENTION The alarm control module receives signals from a multitude of internal or remotely located sensors and provides logic and timing functions so that an appropriate alarm indicating device is actuated. A horn that produces at least IOO-db. sound pressure level is used as an internal alarm indicating device. Two outputs from the system are used for remotely located alarm indicating devices. One output is a relay controlled outlet providing 1 17 volts AC at 600 watts. The second output is a set of normally open or normally closed dry relay contacts which carry current up to 1 amp.
Various combinations of the alarm module outputs can be selected by the switching circuitry incorporated in the equipment. The function selector enables the output or combination of outputs as selected. When an alarm trigger signal occurs, the outputs that are enabled will then be actuated; the outputs remain actuated until the system is reset or until a complete loss of power occurs.
The system has two basic alarm trigger inputs. Triggering input A causes all logic and timing functions to act normally and causes the output reaction to be that established by the function selector. Input B, referred to as the instant alarm input, bypasses all timing functions and function selection; a trigger at input 8 causes all outputs to be actuated instantaneously regardless of control positions.
Provisions are made in the system to accept three kinds of internal modules or sensors, which are a heat sensor, an ultrasonic intruder detector module, and a radiofrequency receiver module. All low-voltage inputs and outputs of the system are located on terminal strips mounted on the rear of the modules. ll7-Volt AC 60-cycle power or internal rechargeable battery power operates the system which is always ready irrespective of external power distribution systems or switches.
The internal ultrasonic intruder detection system is connected to the first triggering input channel to employ all logic and timing functions. Preferably a system is used such as described in copending application Ultrasonic Detection System, filed Mar. 10, 1969, by C. H. Peterson'and C. C. Krueger, is used. An internal radio receiver is connected to the same triggering input channel as the ultrasonic intruder detection system. Alternatively, the receiver may be connected to the immediate response input channel. When the receiver is keyed by radiofrequency within its sensitivity, logic and timing functions of the control circuit are set into operation. One or more radiofrequency transmitters may be located at convenient locations remote from the alarm control. The transmitters may be operated by buttons depressed by persons who wish to set off the alarm control, or the transmitters may be controlled by remote perimeter metering devices such as black light photoelectric cells, contact or broken circuit sensitive devices. The transmitters may be connected to heat or flame sensitive devices to provide an alarm system with remote wireless fire detection stations. Transmitters may be used with any automatic monitoring systems. Personally carried transmitters may be connected to battery operated health condition monitors.
Each input circuit is provided with external connection jacks terminals so that any external detector may be wired to the alarm control and may activate its immediate response total signal mode or its programmed response mode. Any condition monitor may be connected to either input. The alarm system may be wired to remote panic button stations or to any condition monitor.
Very little power is used in standby operation when AC power is off. The equipment runs for an extended period when the internal battery power operates the system. When AC power is applied to the system, the battery is charged. If the AC power supply fails, the internal battery is automatically switched in and continues to supply power to all the module circuits except the AC outlet.
One objective of this invention is the provision of alarm control systems with function selector means for individually and collectively enabling signaling means to respond to intruders, fire or other energy producing inputs.
This invention has as another objective the provision of alarm control systems which have first and second input channels from sensing means so that sensing means on one channel may operate through a logic control system to control the operation of signaling devices and so that energy sensing means on a second channel may directly operate the signaling devices, bypassing the logic control circuit.
Another objective of this invention is the provision of alarm control apparatus with bistable flip-flop circuits for remaining in an alarm state until intentionally reset.
Another objective of this invention is the provision of alarm control systems having time delay means for operation of localized signals in response to circuit tripping and for immediate operation of remote signals in response to the same tripping and for selection of local and remote signals.
A further objective of this invention is the provision of time delay reset means so that alarm control apparatus may not be deenergized before it has responded to a triggering for a predetermined time.
These and further objectives of the invention will be apparent from this disclosure which includes the specification which is the written material, including the claims, and from the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram of the interrelationship of elements of the invention.
FIG. 2 is a schematic diagram of the electrical components of a preferred embodiment for carrying out the objectives of this invention.
DETAILED DESCRIPTION OF THE DRAWINGS A reference to the functional block diagram FIG. I will aid in understanding the following description. Multiple numbers, for example l-20 refer to elements having those and intermediate numbers in FIG. 2. The equipment is comprised of major circuit sections, which are identified in the drawings as flip-flop 10-20, AC outlet relay 6A, remote output relay 7A, adjustable delay timer 22-30, horn relay 36A, function selector 50, input A, input B, reset delay 43-45, and power supply 51-69. The power supply is connected to all other sections; therefore, for clarity in understanding the interrelation of other sections, the power supply connections are not shown in the schematic FIG. 1.
FLIP-FLOP Every input to the system is first fed to the bistable flip-flop 10-20; the reset command signal is also fed to this stage. This logic element has two stable states. An alarm trigger signal from any input causes the flip-flop to set and remain in the alarm state even though the alarm trigger may be momentary. The flip-flop remains in the alarmed state until a reset pulse occurs and causes the flip-flop to assume its original no alarm state. The remainder of the system therefore, reads out the state of the flip-flop and acts accordingly. Both outputs of this logic element are used to drive the circuitry that follows.
AC OUTLET RELAY I l7-volt AC power is applied to the AC outlet when the AC outlet relay contacts close. A transistor switch 9 acts as the relay coil driver. When the flip-flop 10-20 is in the alarm state, a relay driver transistor 9 switches on and connects one side of the AC outlet relay coil 6A to 8+. The other side of the relay coil is connected to the function selector 50. If the function selector has not been set to enable this relay, an open circuit is presented to the relay, and, the relay is not energized. If the function selector has enabled this relay, the relay circuit completes causing the relay to be energized.
REMOTE OUTPUT RELAY One side of the remote output relay coil 7A is connected to the same relay driver transistor 9 as the AC outlet relay 6A. The remote output relay functions identically to the relay described in the above paragraph; its coil current is enabled or disabled by the function selector 50. A form C relay contact arrangement 78 (FIG. 2) is used to provide both a normally open and normally closed set of relay contact outputs.
ADJUSTABLE DELAY TIMER An adjustable delay timer 22-30 is actuated by the other output of the flip-flop 10-20. When an alarm state occurs in the flip-flop the timer circuit begins to time. A variable potentiometer makes the time delay adjustable from a small fraction of a second to at least 10 seconds. The output of the timer remains in the no alarm state until the time period, as set by the control, is reached. At that time the output of the timer switches to the alarm state. The delayed alarm signal is fed to the horn relay 36A only; therefore, the timer is referred to as the Horn Time Delay Control.
HORN RELAY-FLASHER DC current to the horn is switched on and off by the horn relay contacts. When an alarm signal output occurs from the adjustable delay timer, the horn relay 36A is energized. An electronic horn relay circuit 32-41 associated with the horn relay causes the relay current to be interrupted at time intervals and durations established by the electronic circuit. The acoustical output of the horn, therefore, is not continuous but is a beeping sound. As before, if the function selector has not been set to enable the horn relay, no current flows through the horn relay coil, and no horn output occurs.
FUNCTION SELECTOR The function selector switch 50 has four positions, which are: AC outlet only; AC and horn; AC, horn, and remote output; and remote output only. A diode matrix in conjunction with a single pole rotary switch are used to enable the combinations of outputs.
INPUT A Input A of the flip-flop 10-20 is a normally open input. When any alarm sensor is connected to this input and exhibits a close circuit, the flip-flop is set in the alarmed state. Even if the input reverts back to an open circuit condition almost instantaneously, the flip-flop remains in the alarm state. Because Input A is a normally open circuit configuration, an infinite number of alarm sensors can be connected in parallel to this input. If any one of these alarm sensor circuits close, the alarm trigger and timing functions commence immediately. Maximum current flow in this circuit is 2 milliamperes.
INPUT B Input B, the instant alarm mode input, incorporates a diode matrix circuit to actuate the flip-flop, horn relay driver, and function selector simultaneously. The multiple actuation causes the flip-flop to be set, bypasses the horn time delay circuit, and enables all relay output functions, regardless of the setting of the function selector switch.
As long as Input B remains a closed circuit all functions are actuated instantaneously. If lnput Circuit B reverts to an open circuit at a later time, the output functions that are not selected or enabled by the function selector switch, are shut off, and only those functions selected by the selector switch remain in alarm condition.
RESET When either Input A or Input B is a closed circuit, it is impossible to reset the flip-flop. The system, therefore, remains in the alarmed state until Input A and/or B is cleared.
RESET DELAY Assuming Input A and B are clear, the system cannot be reset until 5 seconds after the horn relay driver circuit 32-41 has been actuated. This holds true regardless of the position of the function selector switch. If the horn is enabled, after the horn time delay period has passed, the horn sounds and continues sounding for a period of 5 seconds even though the reset button has been depressed for the whole duration. It is therefore impossible to disable the alarm control module from sensing an alarm condition and from actuating the selected alarm output.
POWER SUPPLY I l7-volt AC power is converted to l8-volt DC in the power supply section 51-69. DC power is supplied to all active sections of circuitry as well as to the trickle charging circuit for the nickel cadmium standby battery pack. A solid state switching circuit automatically connects the battery into the circuit in the event of AC power loss. In the latter mode of operation there is a 12-volt nominal Brivoltage. All logic and timing functions operate identically at either a standby l2-volt voltage or the normal l8-volt voltage. There are two means for identifying on which power mode the equipment is functioning. A pilot lump indicates when AC power is applied to the equipment. A dark pilot light indicates a loss of AC power or that the AC power switch on the rear of the module is in the off position. There is also a noticeable difference in pitch of the audible horn signal, a pure tone indicating standby battery operation.
The power supply also supplies DC power to the internal RF receiver module and the internal ultrasonic intruder detector module. Since the internal heat sensor and the remote accessories connected to the remote input terminals are'all passive devices, they do not require power. Under no alarm conditions, the power consumption is very minimal, allowing at least 8 hours of standby power operation. When the system is in the alarmed condition, the power consumption is dependent on the number of functions that are enabled. If the horn is actuated in standby battery mode of operation, 5 to 30 minutes of horn operation is available, depending on the duration of AC power loss before the horn was actuated. When a standby battery pack has been completely discharged, 16 hours of AC operation is required to fully recharge the bat tery.
DETAILED CIRCUIT DESCRIPTION In FIG. 2, components utilized for the circuitry herein described are designated by numbers. Letter designations are used to indicate connecting points to conventional associated circuitry or electronic components, which, because they are conventional are not described in full detail. The detailed circuit description of FIG. 2 fully describes all parts associated with the alarm control module. The total system is a completely effective self-contained system without the use of accessory equipment. However, accessory alarm sensors or remote alarm indicating systems can be connected to this system to further improve its effectiveness and versatility.
ALARM INPUT A AND INPUT B Input terminals C and L are connected to the input of the flip-flop through resistor 12. Resistor l2 and capacitor 5 serve as an RF filter network to suppress any radiofrequency currents that may exist on their respective connecting wires. Diode l connects Input Terminals A and O to the input of the flip-flop circuit. Terminals B, D, K and N serve as the ground return for each of the four input terminals aforementioned. When a closed circuit condition exists between either Terminals A and C or L and O and circuit ground, a low-resistance ground will be exhibited at the base of Transistor l9. Normally on transistor 19 in the flip-flop circuit will, therefore, be shut off by that input circuit condition.
ALARM VOLTAGE INPUT Terminal R connects to the alarm output of the ultrasonic intruder detector module. The output of that module is a DC voltage proportional to the amount of motion that the detector senses. Resistors 72 and 71 and transistor 73 comprise a DC threshold transistor switch. When a certain DC level has been exceeded at terminal R, transistor 73 will switch on, causing a low-resistance condition between collector and emitter connections of transistor 73. This DC threshold switching action also causes a low resistance to ground condition at the input of the flip-flop circuit.
BISTABLE MEMORY The system described herein has incorporated a flip-flop circuit design for normally open alarm circuits. The particular design techniques utilized cause the flip-flop to always come on in the same state. When a closed circuit exists on its input, the flip-flop changes state. The flip-flop remains latched in that state until it is reset by the use of a separate signal. With slight modification, the same design is extended to include both normally open and normally closed input circuits simultaneously. Elements 10 through 21 comprise the components used in the flip-flop circuit. Resistors 10 and 11 serve as the collector load resistors for transistor 15, the normally off transistor of the flip-flop. Resistors 13 and to serve as the cross coupling impedances from each collector to each other's base. Resistor M in conjunction with resistor 13 determine the voltage threshold characteristics of transistor 15. Resistor l7 and resistor 18 in conjunction with resistor 16 determine the voltage threshold characteristics of transistor 19. Resistor 20 serves as the collector mode resistor for transistor 19. By intentionally making the resistance of resistor 20 much larger than that of resistors 10, and I1, transistor 19 saturates more easily than transistor 15. It is for this reason that transistor 19 is always the on transistor in the normal state. Since transistors 15 and 19 are cross coupled, the states of each are always opposite each other. Therefore, one or the other is on, and one or the other is off. This action causes current to flow always through diode 21. The voltage drop across diode 21 remains essentially constant and serves as back-bias to transistors 15 and 1 .9, ensuring that the off transistor is definitely ofl". Although the flip-flop shown herein by way of example is designed for circuit closing alarm sensors, conventional modification makes the flip-flop suitable for use with circuit opening alarm sensors.
RELAY DRIVER When an alarm signal triggers the flip-flop, transistor 9 turns on due to current flow through resistor 11 and transistor 15 of the flip-flop. Relay coils 6A and 7A are connected to the collector of transistor 9. Therefore, one side of each of the relay coils is now at a positive potential. When the other side of either of these coils is grounded, that coil is energized. The position of function selector switch 50 determines whether or not either of these relays are grounded, enabling either or both of them to be energized when the alann trigger occurs.
RELAY 6 AND RELAY 7 Relay contacts 68 and 7B are shown in the deenergized state. When coil 6A is energized, contacts 68 close, applying l20-volt AC power to AC outlet IJ. When relay coil 7A is energized, contacts 78 switch from position 1 to position 2, causing output terminals E and F to change to an open circuit and output terminals G and H to present a closed circuit. Remote alarm control apparatus connected to either of those output terminal pairs sense the change of state and actuate their particular alarm modes. Diode 8 protects transistor 9 from any inductive kickback surges from relay coils 6A or 7A.
HORN DELAY TIMER It is normally very difficult to design a circuit with a time delay range ratio as high as the circuit designed in this system and to maintain a linear time scale on the time delay adjustment control. The time delay circuit of the present invention resets itself instantaneously and can immediately resume the same timing cycle with a very small amount of error. Circuit components 22 through 30 serve as the adjustable delay timer. Normally capacitor 24 is grounded through resistor 23, diode 22, and flip-flop transistor 19. Adjustable resistor 30 and resistors 29 and 28 serve as a variable voltage bias network in the emitter circuit of transistor 26. Transistor 26 is normally off, since the emitter voltage is higher than the base voltage in the no alarm state. When an alarm trigger occurs, transistor 19 shuts off, causing diode 22 to reverse bias, thereby ungrounding capacitor 24, which begins to charge towards B+ through resistor 25. When its base voltage exceeds its emitter voltage by 0.6 volts, transistor 26 turns on. If variable resistor 30 is set at maximum resistance, the greatest amount of voltage exists at the emitter of transistor 26. That condition establishes the maximum time delay as established by the RC product of resistor 25 and capacitor 24. At that time, capacitor 24 will have accumulated enough charge so that its potential is higher than the emitter potential, and transistor 26 turns on. The delayed alarm trigger signal, therefore, is located across resistor 27. The time delay can be varied between minimum and maximum limits established by the variation of emitter potential on transistor 26.
HORN RELAY CIRCUIT Elements 32 through 41 comprise the horn relay circuit. Resistor 32 establishes the base current flow for transistor 33. When an alarm signal exists at the output of the adjustable horn delay timer circuit, transistor 33 is turned on causing the collector potential of transistor 33 to raise from zero to 13+ voltage. Diode 34 couples this plus voltage to the horn flashing circuit. The simple electronic circuit used in conjunction with the horn relay coil causes a flasher action. The flashing rate and flashing duration is easily adjustable and can be varied over a wide range. The power consumption is very minimal when compared to standard flasher devices that typically work on a thermal heating effect of a bimetallic contact arrangement. There is an order of magnitude improvement in the consistency of the timing factors under the conditions of varying supply voltage as compared to the typical thermal flasher unit. Transistor 38, resistors 37 and 40, capacitor 39 and unijunction transistor 41 comprise an electronic multivibrator circuit, causing relay coil 36A to be energized and deenergized at a predetermined rate. Relay contacts 368 close and open, respectively causing horn 74 to be energized and deenergized. RC product of resistor 40 and capacitor 39 determine the on time of the multivibrator circuit. Diode 35 protects transistor 38 from inductive kickback voltages from relay coil 36A. The relay circuit can be energized only when it is connected to ground. This again depends on the position of function selector switch 50.
FUNCTION SELECTOR Function selection used in this apparatus eliminates the use of a complex multiple-pole selector switch. The combination of diodes and a one-pole switch yields an extremely simple solution to a typically difficult problem. There is a suitable diode configuration for any combination of functions that one desires to be able to select. Function selector switch 50 enables relays 6A, 7A and 36A in the following manner. In position 1 relay 6A is grounded, and relays 7A and 36A are ungrounded due to diode 47 being back-biased. In position 2 relay 36A grounds directly, relay 6A grounds through diode 47 being forward biased, and relay 7A remains ungrounded due to diode 48 being back-biased. In position 3 relays 6A, 7A and 36A are grounded due to diodes 47, 48 and 49 forward conducting. In position 4 relay 7A grounds directly, and relays 6A and 36A are ungrounded due to diode 49 being backbiascd. The function selector, therefore, allows various combinations of events to occur when the alarm system has been triggered.
INSTANT ALARM CIRCUIT Diode matrixes of the function switch and Input B produce an all-function enabling override regardless of switch position. This second logic loop forms the basis for many of the unique features and functions that are displayed in this equipments design. This section of circuitry also overrides the adjustable time delay circuit function. Circuit components 31, 2, 3 and 4 cause an overriding chain of events to occur. Resistor 31 maintains input terminal A at a positive potential, back biasing diodes l, 2 and 4 to maintain an out of circuit condition. When a closed circuit exists between terminals A and B or terminals N and O, voltage at A drops to zero, causing diodes l, 2 and 4 to conduct. Since the anode of diode 4 is connected to position 3 of function selector switch 50, relays 6A, 7A and 36A are effectively grounded. The conduction of diode 1 causes the flip-flop to be triggered to the alarmed state. Therefore, relay 6A and 7A are instantly energized, regardless of the position of function switch 50. The conduction of diode 2 causes the emitter potential of transistor 26 to be dropped to close to zero volts, which supercedes any preset timing delay voltage in the circuit; the horn relay circuit is energized instantaneously. Relay 36A also is energized instantaneously due to the fact that it grounds through diode 4, regardless of the position of function switch 50. The instant alarm input, therefore,
triggers all output circuits as long as a closed circuit exists at the input terminals. When an open circuit condition is reestablished, the output circuits that remain energized will be determined by the position of function selector switch 50. The flip-flop is still in the alarmed state.
RESET CIRCUIT The present method of reset timing does not allow the system to become completely disarmed. An alarm output will always occur for at least 5 seconds for any trigger caused by any sensor that is connected to the input of the system. There is no need to incorporate keylock switches and other such devices in order to provide a secure system.
The flip-flop remains in the alarmed state irregardless of which input circuit has triggered it; the trigger can be of a momentary or continuous nature depending on the source. A means of resetting the flip-flop must be provided. Two conditions must exist before the flip-flop can be reset; a specific time interval must exist after the horn circuit has been energized, and all input circuits must be cleared. Components 43, 44 and 45 act as a timing pulse circuit, determining the time interval before the flip-flop can be reset. When the horn circuit has been energized, capacitor 44, begins to charge through resistor 43. The voltage versus time relationship established by this RC product determines the amount of time delay. Unijunction transistor 45 does not fire until reset switch 46 has been depressed. Even if reset switch 46 is depressed before or at the time of alarm trigger, a reset pulse is not generated until capacitor 44 charges to the firing potential of unijunction transistor 45. At that time a positive pulse will appear at the base of flip-flop transistor 19, causing the flip-flop to be reset to its original state, with transistor 19 in the on condition.
AC PRIMARY CIRCUIT Reference 51 connects to -volt AC 60-cycle power source; the third wire represents the equipment ground return. Switch 53 acts as the AC power on and off switch. Fuse 54 will open circuit due to fault currents in either transformer 58 of AC outlet IJ. This protects all internal wiring as well as relay contacts 68 against an over current situation. Resistors 55, 56, and neon lamp 57 are used to indicate when AC power is applied to the electronic circuitry. With l20-volt AC applied across the primary of transformer 58A, a voltage stepdown to 12 volts AC occurs at secondary 588. Secondary AC voltage is rectified by diodes 59, 60, 61 and 62 to produce a DC output voltage of approximately 19 volts. Capacitors 63, 64 and 65 filter out AC ripple from the rectification process to produce an acceptable pure DC voltage, referred to as B+ voltage. B+ voltage is fed to all active circuits contained in the alarm control module and is fed to terminals Q and S to supply power to auxiliary equipments.
INTERNAL STANDBY POWER Elements 66 through 69 comprise the internal standby battery power system. Switch 68 connects or disconnects battery 69 from the circuitry. It also connects or disconnects the B+ voltage to terminals which feed DC power to auxiliary equipment. Battery 69 is a nickel cadmium battery capable of being charged and discharged many times. With switch 68 on, resistor 67 determines the trickle charge current. Diode 66 is back-biased when AC power is applied; therefore, the rectified AC supplies all circuit power, and battery 69 is effectively disconnected from the circuit and is in a trickle charging mode. When AC power fails, B+ voltage begins to drop. When it drops 0.6 volts below the battery voltage, diode 66 conducts and automatically connects battery 69 to the B+ line, allowing the battery to supply uninterrupted power to the electronic circuitry. The intentional voltage difference between the two sources of DC power allows the standby power switchover arrangement to be utilized.
DC ClRCUlT TO ULTRASONIC MODULE Switch 70 when closed applies the battery voltage to terminal P to enable and supply standby power to the ultrasonic intruder detector module. When switch 70 is opened or in the off position, the ultrasonic intruder detector module is disabled or disarm'ed and, therefore, is not capable of triggering the alarm control module, irregardless of the positions of switch 68 or 53.
Switches 53 and 68, being in the off position, disarms the complete system. All alarm inputs are armed when either switch 53 or switch 68 in on.
That which is claimed is:
ljAlarm control apparatus comprising:
energy sensing input means,
control circuit means connected to the energy sensing input means,
power source connected to thecontrol circuit means,
more than one signalling means connected to the control circuit means,
function selector means connected to each signalling means separately from the control circuit means for individually and I collectively enabling the signalling means for response to the energy sensing means and control means.
2. The alarm control apparatus of claim 1 wherein the energy sensing input means comprises first and second energy sensing input means, and wherein the secondenergy sensing input means is connected to the signalling means, whereby the signalling means operates in response to the control circuit means in response to energy sensing by the first input means, and whereby the signalling means directly operate in response to energy sensing by the second input means.
3. The alarm control apparatus of claim 2 wherein the energy sensing input means comprises first and second energy sensing input means, and wherein the second input means is connected to the function selector means for selectively enabling the signalling means in responseto energy sensing by the second input means.
4. The alarm control apparatus of claim 3 wherein the first energy sensing input means comprises an ultrasonic intruder detector means and wherein the second energy sensing input means comprises heat sensor means.
5. The alarm control apparatus of claim 4 wherein the first energy sensing means additionally comprises a radiofrequency receiver and connection means for remote accessories, and wherein the second input means further comprises second connections for remote accessories.
6. The alarm control apparatus of claim 1 wherein the control circuit comprises a bistable flip-flop circuit connected to the energy sensing input means.
7. The alarm control apparatus of claim 6 wherein the control circuit means further comprises relay driver means connected to the flip-flop means and signal relay means connected to the relay driver means for controlling the signalling means.
8. The alarm control apparatus of claim 7 wherein the control circuit means further comprises adjustable delayed timer means interposed between the flip-flop circuit and the relay driver means, a reset switch means connected to the flip-flop means and reset delay means connected between the relay driver means and the reset switch means for delaying resetting of flip-flop to a no alarm condition.
9. The apparatus of claim 1 wherein the control circuit means include time delay apparatus comprising a first normally on transistor having an emitter connected to ground, a diode connected to a collector of the first transistor, a capacitor connected between the diode and ground, a first resistor connected between the capacitor and a source of DC power whereby the capacitor is charged through the first resistor when the first transistor is 01?, a second transistor having a base connected to the capacitor and having an emitter-collector circuit connected to a source of power and to an alarm response circuit for operating the alarm response circuit when the second transistor is conductive, an emitter of the second transistor being connected through second resistor to a source of power and through a potentiometer to ground whereby the emitter is held at a voltage higher than the'base when the capacitor is grounded through the first transistor, and whereby adjusting the potentiometer controls the time required after the first transistor has been turned off for the capacitor to charge sufiiciently toturn the second transistor on thereby completing circuit means b etween the power source and a signalling means. i I
1 0. The apparatus of claim 1' wherein the function sel ectbr means includes a function selector switch for selectively connecting a single movable pole to first,second and third connecting lines which are connected to respective signalling means contacts comprising: a movable pole, a first contact connected to a first line, a second contact connected'to the second line and connected via a unidirectional element to the first line, a third contact connected to the 'thirdline, anda fourth contact connected to the third contact via a unidirectional element and connected to the second contact via a unidirectional element, whereby thefirst contact provides a pole contact for the firstv line, the second contact provides a pole contact for first and second lines, the third contact provides ground contact for the third line and thefourth contact provides pole contact for first, second and third lines.
11. The apparatus of claim 1 wherein the control circuit means includes a reset time delay comprising a unijunction transistor connected to a source of power and to an alarm reset switch which is in turn connected to a flip-flop circuit, a unijunction transistor having a biasing connection connected to a capacitor which is grounded on one side thereof and which is connected through a resistance to the output of a time delay relay, whereby closing the alarm reset switch after the time delay relay has become energized charges the capacitor through the resistance to a potential required to make the unijunction transistor conductive enabling resetting of the control circuit means after a time delay.
12. An alarm control system comprising first and secondenergy sensing input means,
controlcircuit means connected to the energy sensing input means,
signalling means connected to the control circuit means and to the second energy sensing means for controlled response to the energy sensing of the first input means and for direct response to energy sensing by the second input means,
function selector means connected to the signalling means separately from the control circuit means for severally enabling the signalling means for response to the sensing means and control means, and
power source means connected to the control circuit means and to the signalling means.
13. The alarm control system of claim 12 wherein the second energy sensing input means is connected to the function selector means for overriding the function selector means and enabling all signalling means for response to energy sensing in the second input means.
14. The alarm control system of claim 13 wherein the control circuit means comprises a bistable flip-flop connected to the first and second energy sensing input means,
an adjustable delay timer connected to the bistable flip-flop,
first and second relay drivers respectively connected to the flip-flop and to the adjustable delay timer,
an AC outlet relay and a remote output relay connected to the first relay driver,
a horn relay connected to the second relay driver,
a reset delay and reset switch connected between the second relay driver and the flip-flop for resetting the flipflop after a time delay,
and wherein the function selector is connected to the AC outlet relay, to the remote output relay, and to the horn relay, whereby the function selector may select either AC outlet control, AC outlet control and horn operation, AC outlet control, horn operation and remote output, or remote output,
and wherein the second energy sensing input means is connected to the flip-flop, to the second relay driver and to the function selector for overriding the function selector and operating all of the signalling means in response to the energy sensing by the second input means.
15. A self-contained alarm system for sensing the presence of intruders or of excessive heat and for responding by a selfcontained alarm device, comprising a power source having a cord and plug for connection to a conventional ll-volt AC input source and having transformer and rectifier means for producing a relatively low DC voltage from the AC input voltage, multiple signal means connected to the power source, an ultrasonic intruder sensor connected to the power source, a fire sensor having a heat sensitive switch connected to the power source, a radiofrequency sensor, an alarm control circuit connected to the fire sensor, to the ultrasonic intruder sensor and to the radiofrequency sensor and to the signal means and function selector means connected to the signalling means independently of the control circuit, for operating a signal means in response to an input from the sensors.
16. The method of controlling alarms comprising connecting condition sensors to two input channels, connecting the input channels to a bistable flip-flop circuit, changing state of the bistable flip-flop in response to condition sensing by one of the sensors, connecting a power source to a first set of relay coils in response to changing of state of the flip-flop, beginning operation of a time delay circuit in response to changing of state of the flip-flop, connecting the power source to a relay for operating the local signal in response to completion of the time delay circuit and selectively grounding any or all of the relays preparatory to the changing of state of the flip-flop device, whereby selected relays are enabled for causing operation of relay switches in response to changing of state of the flip-flop device.
17. The method of claim 16 further comprising overriding the time delay and function selector and actuating all signals when input is received on a selected one of the input channels.
18. The method of claim 18 wherein the beginning operation of a time delay circuit comprises the sequential steps of biasing a first transistor off by providing an emitter potential higher than a base potential, shorting a capacitor connected to the transistor base, unshorting the capacitor upon a start signal, slowly charging the capacitor to a potential above emitter potential, thereby causing the transistor to turn on completing an alarm circuit and controlling time delay by varying emitter potential.

Claims (18)

1. Alarm control apparatus comprising: energy sensing input means, control circuit means connected to the energy sensing input means, power source connected to the control circuit means, more than one signalling means connected to the control circuit means, function selector means connected to each signalling means separately from the control circuit means for individually and collectively enabling the signalling means for response to the energy sensing means and control means.
2. The alarm control apparatus of claim 1 wherein the energy sensing input means comprises first and second energy sensing input means, and wherein the second energy sensing input means is connected to the signalling means, whereby the signalling means operates in response to the control circuit means in response to energy sensing by the first input means, and whereby the signalling means directly operate in response to energy sensing by the second input means.
3. The alarm control apparatus of claim 2 wherein the energy sensing input means comprises first and second energy sensing input means, and wherein the second input means is connected to the function selector means for selectively enabling the signalling means in response to energy sensing by the second input means.
4. The alarm control apparatus of claim 3 wherein the first energy sensing input means comprises an ultrasonic intruder detector means and wherein the second energy sensing input means comprises heat sensor means.
5. The alarm control apparatus of claim 4 wherein the first energy sensing means additionally comprises a radiofrequenCy receiver and connection means for remote accessories, and wherein the second input means further comprises second connections for remote accessories.
6. The alarm control apparatus of claim 1 wherein the control circuit comprises a bistable flip-flop circuit connected to the energy sensing input means.
7. The alarm control apparatus of claim 6 wherein the control circuit means further comprises relay driver means connected to the flip-flop means and signal relay means connected to the relay driver means for controlling the signalling means.
8. The alarm control apparatus of claim 7 wherein the control circuit means further comprises adjustable delayed timer means interposed between the flip-flop circuit and the relay driver means, a reset switch means connected to the flip-flop means and reset delay means connected between the relay driver means and the reset switch means for delaying resetting of flip-flop to a no alarm condition.
9. The apparatus of claim 1 wherein the control circuit means include time delay apparatus comprising a first normally on transistor having an emitter connected to ground, a diode connected to a collector of the first transistor, a capacitor connected between the diode and ground, a first resistor connected between the capacitor and a source of DC power whereby the capacitor is charged through the first resistor when the first transistor is off, a second transistor having a base connected to the capacitor and having an emitter-collector circuit connected to a source of power and to an alarm response circuit for operating the alarm response circuit when the second transistor is conductive, an emitter of the second transistor being connected through second resistor to a source of power and through a potentiometer to ground whereby the emitter is held at a voltage higher than the base when the capacitor is grounded through the first transistor, and whereby adjusting the potentiometer controls the time required after the first transistor has been turned off for the capacitor to charge sufficiently to turn the second transistor on thereby completing circuit means between the power source and a signalling means.
10. The apparatus of claim 1 wherein the function selector means includes a function selector switch for selectively connecting a single movable pole to first, second and third connecting lines which are connected to respective signalling means contacts comprising: a movable pole, a first contact connected to a first line, a second contact connected to the second line and connected via a unidirectional element to the first line, a third contact connected to the third line, and a fourth contact connected to the third contact via a unidirectional element and connected to the second contact via a unidirectional element, whereby the first contact provides a pole contact for the first line, the second contact provides a pole contact for first and second lines, the third contact provides ground contact for the third line and the fourth contact provides pole contact for first, second and third lines.
11. The apparatus of claim 1 wherein the control circuit means includes a reset time delay comprising a unijunction transistor connected to a source of power and to an alarm reset switch which is in turn connected to a flip-flop circuit, a unijunction transistor having a biasing connection connected to a capacitor which is grounded on one side thereof and which is connected through a resistance to the output of a time delay relay, whereby closing the alarm reset switch after the time delay relay has become energized charges the capacitor through the resistance to a potential required to make the unijunction transistor conductive enabling resetting of the control circuit means after a time delay.
12. An alarm control system comprising first and second energy sensing input means, control circuit means connected to the energy sensing input means, signalling means connected to the control circuit means and to the second energy sensing means for controlled response to the energy sensing of the first input means and for direct response to energy sensing by the second input means, function selector means connected to the signalling means separately from the control circuit means for severally enabling the signalling means for response to the sensing means and control means, and power source means connected to the control circuit means and to the signalling means.
13. The alarm control system of claim 12 wherein the second energy sensing input means is connected to the function selector means for overriding the function selector means and enabling all signalling means for response to energy sensing in the second input means.
14. The alarm control system of claim 13 wherein the control circuit means comprises a bistable flip-flop connected to the first and second energy sensing input means, an adjustable delay timer connected to the bistable flip-flop, first and second relay drivers respectively connected to the flip-flop and to the adjustable delay timer, an AC outlet relay and a remote output relay connected to the first relay driver, a horn relay connected to the second relay driver, a reset delay and reset switch connected between the second relay driver and the flip-flop for resetting the flip-flop after a time delay, and wherein the function selector is connected to the AC outlet relay, to the remote output relay, and to the horn relay, whereby the function selector may select either AC outlet control, AC outlet control and horn operation, AC outlet control, horn operation and remote output, or remote output, and wherein the second energy sensing input means is connected to the flip-flop, to the second relay driver and to the function selector for overriding the function selector and operating all of the signalling means in response to the energy sensing by the second input means.
15. A self-contained alarm system for sensing the presence of intruders or of excessive heat and for responding by a self-contained alarm device, comprising a power source having a cord and plug for connection to a conventional 110-volt AC input source and having transformer and rectifier means for producing a relatively low DC voltage from the AC input voltage, multiple signal means connected to the power source, an ultrasonic intruder sensor connected to the power source, a fire sensor having a heat sensitive switch connected to the power source, a radiofrequency sensor, an alarm control circuit connected to the fire sensor, to the ultrasonic intruder sensor and to the radiofrequency sensor and to the signal means and function selector means connected to the signalling means independently of the control circuit, for operating a signal means in response to an input from the sensors.
16. The method of controlling alarms comprising connecting condition sensors to two input channels, connecting the input channels to a bistable flip-flop circuit, changing state of the bistable flip-flop in response to condition sensing by one of the sensors, connecting a power source to a first set of relay coils in response to changing of state of the flip-flop, beginning operation of a time delay circuit in response to changing of state of the flip-flop, connecting the power source to a relay for operating the local signal in response to completion of the time delay circuit and selectively grounding any or all of the relays preparatory to the changing of state of the flip-flop device, whereby selected relays are enabled for causing operation of relay switches in response to changing of state of the flip-flop device.
17. The method of claim 16 further comprising overriding the time delay and function selector and actuating all signals when input is received on a selected one of the input channels.
18. The method of claim 18 wherein the beginning operation of a time delay circuit comprises the sequential steps of Biasing a first transistor off by providing an emitter potential higher than a base potential, shorting a capacitor connected to the transistor base, unshorting the capacitor upon a start signal, slowly charging the capacitor to a potential above emitter potential, thereby causing the transistor to turn on completing an alarm circuit and controlling time delay by varying emitter potential.
US814537A 1969-04-09 1969-04-09 Alarm control Expired - Lifetime US3613064A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US81453769A 1969-04-09 1969-04-09

Publications (1)

Publication Number Publication Date
US3613064A true US3613064A (en) 1971-10-12

Family

ID=25215350

Family Applications (1)

Application Number Title Priority Date Filing Date
US814537A Expired - Lifetime US3613064A (en) 1969-04-09 1969-04-09 Alarm control

Country Status (1)

Country Link
US (1) US3613064A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3848231A (en) * 1970-12-31 1974-11-12 Baldwin Electronics Inc Alarm system utilizing pulse position modulation and dual conductor sensor
US3967261A (en) * 1974-10-10 1976-06-29 Fudaley Solly L Proximity sensor with simultaneously active intermixed sensor types
US4365238A (en) * 1979-06-08 1982-12-21 Adam Kollin Visual signalling apparatus
US5742231A (en) * 1996-07-16 1998-04-21 Kolodin; Louis Intrusion detection system
US5764143A (en) * 1997-05-29 1998-06-09 Napco Security Systems, Inc. Combination temperature unit/intruder sensor utilizing common components
US20080291036A1 (en) * 2007-05-25 2008-11-27 Robert Charles Richmond Multifunction smoke alarm unit

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2703367A (en) * 1950-06-02 1955-03-01 Florman Irving Radiation detector means on vehicles and like carriers
US3200393A (en) * 1962-06-18 1965-08-10 Emmett J Worley Electric burglar alarm system with exit and entry delay
US3212079A (en) * 1961-03-18 1965-10-12 Eberle & Kohler Kommanditgesel Signalling arrangement
US3257653A (en) * 1963-06-21 1966-06-21 Benrus Watch Company Inc Alarm system
US3260991A (en) * 1963-03-20 1966-07-12 American District Telegraph Co Apparatus for detecting motion and objects
US3380044A (en) * 1964-09-04 1968-04-23 Sensor Corp Universal-sensor control system
US3401234A (en) * 1965-04-16 1968-09-10 Rimac Ltd Combined audio program and alarm signaling system with line supervision

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2703367A (en) * 1950-06-02 1955-03-01 Florman Irving Radiation detector means on vehicles and like carriers
US3212079A (en) * 1961-03-18 1965-10-12 Eberle & Kohler Kommanditgesel Signalling arrangement
US3200393A (en) * 1962-06-18 1965-08-10 Emmett J Worley Electric burglar alarm system with exit and entry delay
US3260991A (en) * 1963-03-20 1966-07-12 American District Telegraph Co Apparatus for detecting motion and objects
US3257653A (en) * 1963-06-21 1966-06-21 Benrus Watch Company Inc Alarm system
US3380044A (en) * 1964-09-04 1968-04-23 Sensor Corp Universal-sensor control system
US3401234A (en) * 1965-04-16 1968-09-10 Rimac Ltd Combined audio program and alarm signaling system with line supervision

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3848231A (en) * 1970-12-31 1974-11-12 Baldwin Electronics Inc Alarm system utilizing pulse position modulation and dual conductor sensor
US3967261A (en) * 1974-10-10 1976-06-29 Fudaley Solly L Proximity sensor with simultaneously active intermixed sensor types
US4365238A (en) * 1979-06-08 1982-12-21 Adam Kollin Visual signalling apparatus
US5742231A (en) * 1996-07-16 1998-04-21 Kolodin; Louis Intrusion detection system
US5764143A (en) * 1997-05-29 1998-06-09 Napco Security Systems, Inc. Combination temperature unit/intruder sensor utilizing common components
US20080291036A1 (en) * 2007-05-25 2008-11-27 Robert Charles Richmond Multifunction smoke alarm unit
US7994928B2 (en) * 2007-05-25 2011-08-09 Robert Charles Richmond Multifunction smoke alarm unit

Similar Documents

Publication Publication Date Title
US4199754A (en) Circuit for an emergency lighting and fire detector system
US4204201A (en) Modular alarm system
US4264034A (en) Digital thermostat
US4752698A (en) Emergency supervisory system
US5786644A (en) Two wire PIR occupancy sensor utilizing a rechargeable energy storage device
US4103294A (en) Intruder deterrent apparatus and method
US3289194A (en) Power line sensing appliance theft alarm
WO2009099662A1 (en) Arrangement for controlling and testing a notification appliance circuit
US3613064A (en) Alarm control
US3707708A (en) Muting circuit for a security alarm system providing a sonic alert
GB1584045A (en) Fire alarms
US6049446A (en) Alarm systems and devices incorporating current limiting circuit
US4365167A (en) Switchover system for binary load control
US3974426A (en) In-line energization and de-energization of an external load in series with an external source of electricity in response to externally sensed parameters
US3629608A (en) Remote control circuits
US4074248A (en) Dual operating control circuits for intrusion detection systems
US4477798A (en) Fire Alarm control system
US3678509A (en) Security alarm system
US3962696A (en) Protective systems
US3653041A (en) Annunciator system
JPS6017156B2 (en) fire alarm system
US3582717A (en) Humidity-responsive circuit
US3854127A (en) Alarm system with automatic ringback
US4234834A (en) D.C. Motor directional control
US3801971A (en) Telephone alarm system