Responsive To Intruder Energy Patents (Class 340/565)
  • Patent number: 4841163
    Abstract: A proximity switch immune to interference fields includes an oscillator circuit (1) that can be influenced by a permanent magnet, this circuit being damped in the basic condition by a core of a coil (13), which core consists of an amorphous metal, and being undampable by the approach of the permanent magnet. In order to prevent triggering of the proximity switch by a magnetic alternating field, a signal evaluating circuit (2), yielding a switching signal corresponding to the undamped condition of the oscillator circuit (1), and a signal evaluating circuit (8) are connected to the oscillator circuit output (17). The signal evaluating circuit (8) detects an output signal produced by a magnetic alternating field separately as interference and blocks, by way of a blockable holding circuit (5), the switching signal path so long as a magnetic alternating field is present.
    Type: Grant
    Filed: February 16, 1988
    Date of Patent: June 20, 1989
    Assignee: Werner Turck GmbH Co., KG.
    Inventor: Jens Mueller
  • Patent number: 4823367
    Abstract: The present invention provides a method and apparatus for counting the number of occurrences that a mobile unit comes within range of a stationary unit. The invention is useful in counting the number of laps which a runner or swimmer completes through a course. In one aspect, the present invention includes a timer which, in cooperation with the information generated by the lap counter, produces information corresponding to the lap time, average minutes per mile and other such data. In a preferred embodiment, a stationary transmitter emits an infrared signal to create a zone of detection which triggers a receiving unit attached to the runner or swimmer each time the runner or swimmer passes through the zone of detection.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: April 18, 1989
    Assignee: Rikagaku Kenkyujyo and Hochiki Corp.
    Inventor: Robert J. Kreutzfeld
  • Patent number: 4783379
    Abstract: The present invention provides a film comprising alternate layers of a metal such as zirconium and silicon. The film has a critical temperature at which the film can undergo explosive crystallization. The film undergoes explosive crystallization upon subjecting the film to an energy impulse at temperature equal to or greater than the critical temperature.
    Type: Grant
    Filed: April 17, 1987
    Date of Patent: November 8, 1988
    Assignee: Tosoh SMD, Inc.
    Inventors: Charles E. Wickersham, John E. Poole
  • Patent number: 4775853
    Abstract: A device and installation are provided for the instantaneous and simultaneous detection, inside and outside, of radiations emitted in the infrared, visible and ultraviolet spectra by simultaneous physical phenomena having a character of risk, such as intrusion, fire, explosion, leaks of dangerous fluids and electric leaks, disturbances and absence of movement of a regular periodic phemonenon, said radiations being emitted, directly by the phenmonena to be monitored at the time when the risk appears or being caused artifically by directing over an appropriate field of view, in which take place said phemonena, a source of radiation comprised in the infrared, visible and ultraviolet, and adapted to the nature of the phemonena involved, said field of view covered by the detection device having appropriate horizontal and vertical dimensions comprising at least one spectral correction filter known pass band chosen as a function of the nature of the radiation, a linear or circular polarization filter, a microprism a
    Type: Grant
    Filed: December 27, 1985
    Date of Patent: October 4, 1988
    Assignee: Compagnie Francaise de Protection Electrique Proteg (C.F.P.E. Proteg)
    Inventor: Hector Perez Borruat
  • Patent number: 4772875
    Abstract: An intrusion detector has a first sensor for monitoring a first condition and a second sensor for monitoring a second condition in a space to be protected against intrusion; a change in the condition sensed by the first sensor in a target area causes the second sensor to be aligned with the same target area; and if both sensors indicate a change in the respective conditions that they monitor an intrusion is indicated.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: September 20, 1988
    Assignee: Denning Mobile Robotics, Inc.
    Inventors: James F. Maddox, Mark B. Kadonoff, Robert W. George, II, Roger A. Wendt
  • Patent number: 4757304
    Abstract: There is provided a vehicle security system which is especially useful for night workers to secure themselves against burglars previously hidden their vehicles, comprising a sensing unit for detecting the presence of the burglar, and a warning unit for providing a warning to the burglar. Preferably, the security system has a remote control transmitter.
    Type: Grant
    Filed: September 25, 1986
    Date of Patent: July 12, 1988
    Assignee: San Sung Electronics Co. Ltd.
    Inventor: Ki-Ick Rho
  • Patent number: 4746906
    Abstract: Disclosed herein is a dual technology intruder detection system which features a modular optical system by which the field of protection of one subsystem can be changed relative to the field of view of the other by merely altering the orientation of one optical module relative to another. Such modular optical system includes a multifaceted reflector having two sets of planar reflective facets. Depending on the orientation of such multifaceted reflector relative to a separate spherical reflector, two different fields of view are provided, whereby false alarm-producing can be avoided.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: May 24, 1988
    Assignee: Detection Systems, Inc.
    Inventor: David B. Lederer
  • Patent number: 4743886
    Abstract: The monitoring of intrusion detectors is effected by an apparatus for testing the responsiveness to environment-caused, detector-specific useful and spurious signals. This testing apparatus is arranged inside of the intrusion detector and ensures that during installation and during the operation of the intrusion detector its electrical parameters are optimally adjusted. Deviations of these parameters from their nominal values and the location of these deviations are indicated.
    Type: Grant
    Filed: September 23, 1985
    Date of Patent: May 10, 1988
    Assignee: Cerberus AG
    Inventors: Peter Steiner, Rudolf Genahr, David Siegwart
  • Patent number: 4722574
    Abstract: A personnel detection and protection system comprises sensor means for detecting the presence of personnel in a prohibited operational zone, and for deriving signal means indicative of such a detected presence, and control means responsive to the deriving of such signal means to control the operation or movement of equipment in the prohibited zone.
    Type: Grant
    Filed: August 18, 1986
    Date of Patent: February 2, 1988
    Assignee: Coal Industry (Patents) Limited
    Inventors: Derek K. Barham, Philip P. Jenkins
  • Patent number: 4721945
    Abstract: A simulated target for use in conjunction with detection systems using coupled transmission lines. The simulated target is positioned in the vicinity of the transmission line and the response used both to monitor system operation and to calibrate system response levels. The simulated target can be of a type having its electrical length variable under system control or can be purely passive serving to alter the stationary response profile of the system.
    Type: Grant
    Filed: November 14, 1985
    Date of Patent: January 26, 1988
    Assignee: 501 Control Data Canada Limited
    Inventors: Melvin C. Maki, Roger G. Pither, James H. Chalmers
  • Patent number: 4706069
    Abstract: A security system is disclosed which senses a variety of activities which affect a secured area and/or the boundary which defines it and identifies particular activities rather than merely indicating that some activity is present. A transducer comprising an electroded ferroelectric film of polyvinylidene fluoride (PVDF) serves as a transducer which provides different output signals in response to different stimuli and responds simultaneously to thermal and mechanical activity. A signal processor separately recognizes the signals produced in response to different activities and identifies the activities detected. An alarm processor controls the system and generates alarm signals in response to the detection of specific activities.
    Type: Grant
    Filed: April 8, 1986
    Date of Patent: November 10, 1987
    Assignee: RCA Corporation
    Inventors: Edward Tom, Douglas E. McGovern
  • Patent number: 4658386
    Abstract: A device for repelling animals is disclosed which is adapted for use with refuse and garbage containers to discourage entry therein by foraging animals. The device comprises:(a) a detector for remote-sensing the presence of an animal within its vicinity;(b) an ultrasonic sound generator for producing an animal-repelling ultrasonic sound wave; and(c) means for temporarily activating the ultrasonic sound generator when the detector has sensed the presence of an animal within its vicinity.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: April 14, 1987
    Assignee: Mobil Oil Corporation
    Inventor: Kenneth L. Morris
  • Patent number: 4636774
    Abstract: The motion detector of the present invention, together with associated AC switching circuitry form a lighting control system which turns on room lights when the room is occupied, and extinguishes the lights when unoccupied. The detector sensitivity or threshold is adjusted in response to the previously detected conditions, providing reliable indication of both entry and continued presence in the controlled area, and producing few false alarms. The present embodiment of the invention has two threshold levels of detection, the higher level being used to detect initial entry into the room. After entry is detected, the motion detector lowers the threshold to detect the weaker signals usually occurring for continued presence in the area of the detector. When the occupant leaves the area, the motion detector threshold or sensitivity returns to the original value after a timeout period.
    Type: Grant
    Filed: November 8, 1983
    Date of Patent: January 13, 1987
    Assignee: American District Telegraph Company
    Inventors: Aaron A. Galvin, James B. Edson, John K. Guscott
  • Patent number: 4625199
    Abstract: A motion alarm system having a combination of microwave and ultrasonic subsystems is operative to reliably detect true moving targets and to discriminate false targets both caused by target motion reflected outside the surveillance space and by noise and other interfering phenomena. Microwave and ultrasonic signals received from the surveillance space are separately processed to provide ultrasonic motion detection signals and a microwave motion detection signal. A signal processing circuit interdependently combines the signals for producing a correlated system event signal. The presence of a true moving target within the surveillance space produces sufficient correlation to cause the system event signal to meet predetermined alarm criteria. The presence of either interfering phenomena or unwanted reflected outside signals, or both simultaneously, produces insufficient correlation to cause the system output signal to meet the predetermined criteria.
    Type: Grant
    Filed: January 14, 1985
    Date of Patent: November 25, 1986
    Assignee: American District Telegraph Company
    Inventor: Math M. J. Pantus
  • Patent number: 4598168
    Abstract: A strain sensitive coaxial cable is disclosed as comprising a centrally dosed conductor about which is disposed a first insulating layer, and a second conductor disposed coaxially about the center conductor, configured as a helix and dimensioned to loosely fit with respect to the first dielectric layer and to permit relative axial movement generally between the second conductor and the first dielectric layer, whereby more uniform signals, and elastic-inelastic strain discrimination are provided and spurious outputs eliminated. An outer protective sheath is disposed about the helical turns of the second conductor.
    Type: Grant
    Filed: November 29, 1983
    Date of Patent: July 1, 1986
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Gilbert F. Wagner, Arthur C. Tiemann
  • Patent number: 4546344
    Abstract: A temperature compensated alarm system includes a temperature transducer operative to produce an electrical output signal indicative of the ambient temperature, an alarm sensor, an electronic processing module, and a plurality of addressable registers for storing alarm threshold limits applicable at the operative ambient temperature. At selected times the electronic processing module reads a value indicative of the ambient temperature and thereupon determines the applicable alarm threshold limits by addressing the respective registers containing threshold limit data for the particular ambient temperature. In one embodiment, two sets of registers are provided; one set of registers containing higher sensitivity threshold limit data and the second set containing lower sensitivity threshold limit data. The applicable threshold data is determined by the state of a user settable switch.
    Type: Grant
    Filed: March 5, 1984
    Date of Patent: October 8, 1985
    Assignee: American District Telegraph Company
    Inventors: John K. Guscott, Mario Casamassima
  • Patent number: 4544920
    Abstract: Apparatus and method are provided for protecting an unoccupied building. The apparatus includes a noise detector for detecting noises generated by attempts to enter the building. Any noise detected is converted to an electronic signal and conveyed to an activator. The activator turns on a tape player which plays a tape recording of noise such as a barking dog. The noise is played through speakers within the building to give the impression the building is occupied or guarded by a watchdog.
    Type: Grant
    Filed: October 27, 1982
    Date of Patent: October 1, 1985
    Inventor: Jerry J. Hamlin
  • Patent number: 4533907
    Abstract: A swimming pool alarm in the form of an inexpensive compact unit which floats on the water in a swimming pool and which may be anchored to the side of the pool. The unit includes a hollow tubular probe which extends down below the surface of the water in the pool. The probe has an open bottom and a top closed by a flexible metal diaphragm. A piezoelectric ceramic member is attached to the upper surface of the diaphragm, and it serves to detect movements of the diaphragm in response to pressure changes in the air trapped in the upper portion of the probe. An electric circuit is connected to the piezoelectric ceramic member to activate and latch an electric alarm when the air pressure exceeds a predetermined threshold indicating, for example, that wave action in the pool has exceeded a predetermined level due to the fact that someone has fallen into the pool.
    Type: Grant
    Filed: May 9, 1983
    Date of Patent: August 6, 1985
    Inventor: John B. Thatcher
  • Patent number: 4476554
    Abstract: A sound actuated switch including a microphone coupled via an audio amplifier to a reset circuit. When a sound of sufficient intensity is received by the microphone a reset signal is supplied to the counter portion of an oscillator and counter circuit. The counter then begins counting oscillations and produces an "on" control signal until a predetermined count is reached, at which time an "off" control signal is produced. The control signal is supplied to the gate of a switching triac in a switch circuit. The presence of the on control signal causes the switching triac to electrically connect an AC power source to a load, typically a light. A simple, high efficiency DC power supply is also disclosed.
    Type: Grant
    Filed: July 21, 1983
    Date of Patent: October 9, 1984
    Assignee: Jonathan Ehrenreich, Ehrenreich Electronics
    Inventors: Blaine M. Smith, James A. Taylor
  • Patent number: 4468658
    Abstract: An Improved Intruder Detection Module is disclosed that incorporates a compact, unique optical system, a detector array, and an electronic system of a combined size and configuration that permits the Module to be shaped to approximate a normal household wall outlet box and its associated face panel. The optical system incorporates removable facet reflectors enabling the system to monitor any of a variety of different fields of view. The detector array includes pyroelectric elements mounted in an adjacent facing relationship to cause radiation passing through one element to immediately pass through the adjacent element, thereby causing intense white light to which the detector elements are not particularly responsive to generate substantially the same electrical signal in both elements. The electronic system may include a unique self-checking feature to regularly insure that the system is properly functioning, thereby avoiding nonresponse to an intruder.
    Type: Grant
    Filed: December 12, 1980
    Date of Patent: August 28, 1984
    Inventor: John A. Rossin
  • Patent number: 4455631
    Abstract: The apparatus comprises a geophone connected to a circuitry case containing battery, a voltage regulator, a solid state preamplifier and amplifier tuned to respond to seismic signals between 2 and 25 Hz. The amplified seismic signals are rectified and applied to a microammeter connected to efficiently respond to pulsations at the step frequency of walking or crawling personnel. The apparatus can be used to measure seismic noise and to determine soil conditions prior to the emplacement of an intrusion detection system.
    Type: Grant
    Filed: July 20, 1981
    Date of Patent: June 19, 1984
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Ronald D. San Giovanni
  • Patent number: 4418335
    Abstract: An infrared intrusion detector, utilizing as a sensor element a pyroelectric detector element, accomplishes evaluation of the output signal of the detector element with a charge amplifier, for instance by means of a capacitive feedback coupled operational amplifier, the output signal of which is reset at certain time intervals. The evaluation circuit operates independently of the detector capacitance and therefore enables optimum utilization of the pyroelectrical properties. By virtue of the short-circuit operation and the low ohmic properties of the circuit there is obtained a particularly good non-sensitivity against external disturbances and low noise and increased sensitivity.
    Type: Grant
    Filed: September 18, 1981
    Date of Patent: November 29, 1983
    Assignee: Cerberus AG
    Inventor: Rudolf Genahr
  • Patent number: 4415979
    Abstract: The present invention provides a method and detection system for determining whether a person or other animate body is present in a vehicle by analyzing the power of the output signal from a geophone placed in contact with the vehicle structure. First an electrical signal is obtained which is a function of the vibrations emanating from the structure, and this signal is sampled on a contiguous basis over a plurality of time periods of equal duration. From these samples, a determination is then made as to whether a dense accumulation of power exists in the vicinity of the lowest power point of the sampled time periods and whether this lowest power point is above a predetermined minimum level. The system for accomplishing this method may include a seismic transducer used as a sensing device and a micro-computer for processing the output signals from the seismic transducer. The micro-computer will, on a continguous basis, sample about 22/3 seconds of data at a time.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: November 15, 1983
    Assignee: Ensco, Inc.
    Inventor: Walter C. Hernandez
  • Patent number: 4408308
    Abstract: A sound actuated switch including a microphone coupled via an audio amplifier to a reset circuit. When a sound of sufficient intensity is received by the microphone a reset signal is supplied to the counter portion of an oscillator and counter circuit. The counter then begins counting oscillations and produces an "on" control signal until a predetermined count is reached, at which time an "off" control signal is produced. The control signal is supplied to the gate of a switching triac in a switch circuit. The presence of the on control signal causes the switching triac to electrically connect an AC power source to a load, typically a light. A simple, high efficiency DC power supply is also disclosed.
    Type: Grant
    Filed: June 16, 1981
    Date of Patent: October 4, 1983
    Assignee: Ehrenreich Electronics, Inc.
    Inventors: Blaine M. Smith, James A. Taylor
  • Patent number: 4377808
    Abstract: An improved dual-sensor infrared intrusion alarm system includes a motion discriminator that renders the system responsive to only radiation-emanating objects that are moving through the system's scope of surveillance. A positive or negative sensor signal is developed depending on the relative amounts of radiation impinging on the sensors. A switching amplifier selectively discharges one of two capacitors depending on the polarity of the sensor signal. The voltages across the capacitors are coupled to the inputs of a voltage comparator and the capacitor recharge time constants are selected so that an alarm is indicated only when the length of the time interval between the occurrence of a sensor signal of a given polarity and the subsequent occurrence of a sensor signal of the opposite polarity is within prescribed limits, for example, two seconds.
    Type: Grant
    Filed: July 28, 1980
    Date of Patent: March 22, 1983
    Assignee: Sound Engineering (Far East) Limited
    Inventor: Lin Kao
  • Patent number: 4364030
    Abstract: The improved intruder detection system of the present invention, because of its sensor, optical, and electronic systems, is uniquely capable of responding only to radiation from an intruder to signal an alarm. To achieve this, the sensor and optical systems are designed and cooperate to optically reject and balance-out extraneous, nonintruder-related radiation. In addition, the electronic system detects and rejects nonintruder-related inputs by recognizing certain uniquely intruder-related characteristics of the sensor signals, and to only signal an alarm in response to inputs evidencing such characteristics. Preferably the system is designed to reliably sense the presence of an intruder in multiple zones, to be economical to manufacture, easy to install, to be battery-powered and of a long life.
    Type: Grant
    Filed: September 10, 1979
    Date of Patent: December 14, 1982
    Inventor: John A. Rossin
  • Patent number: 4361767
    Abstract: An apparatus and method for automatically de-energizing electrically operable equipment in response to a lack of animal activity in a specified environment for predetermined time period. The apparatus of the present invention utilizes a circuit which is designed to detect activity which generates energy in a certain wavelength range and particularly, sonic energy in a certain environment and is responsive to the lack of activity within a certain predetermined time delay period or interval. Thus, if an activity which generates sonic energy is detected within a confined environment within the predetermined time interval, a signal is generated to energize or maintain energization of one or more electrical devices connected to the system of the invention. Contrariwise, if no sonic energy is detected within the predetermined time interval, there is a resultant de-energization of the electrically operable equipment. A control is provided to adjust the predetermined time delay period.
    Type: Grant
    Filed: March 24, 1980
    Date of Patent: November 30, 1982
    Assignee: National Technical Systems
    Inventors: David C. Pelka, Baron O. A. Grey
  • Patent number: 4344071
    Abstract: An electronic sensing device, operates to actuate a household lighting fixture in response to a sensed environmental condition such as sound or movement within a room. The device is provided with a receiver for sensing the particular environmental condition, a timer responsive to the output of the receiver, switching apparatus for switching on the household lighting fixture in response to the timer, and a power-providing circuit. The timer provides that the lighting fixture will remain on for a preselected time after sensing the environmental condition, and continually resets in the continued presence of the environmental condition. The switching apparatus switches the light fixture on in response to the timer output and further provides circuitry for varying the switched-on duty cycle of the lighting fixture in order to provide a dimmer control. The power-providing circuitry applies a portion of the leading edge of each half cycle of line current to power the circuitry of the sensing device.
    Type: Grant
    Filed: July 10, 1980
    Date of Patent: August 10, 1982
    Assignee: Roger A. Heller
    Inventor: Glenn R. Allen
  • Patent number: 4342987
    Abstract: The improved intruder detection system of the present invention, because of its sensor, optical, and electronic systems, is uniquely capable of responding only to radiation from an intruder to signal an alarm. To achieve this, the sensor and optical systems are designed and cooperate to optically reject and balance-out extraneous, nonintruder-related radiation. In addition, the electronic system detects and rejects nonintruder-related inputs by recognizing certain uniquely intruder-related characteristics of the sensor signals, and to only signal an alarm in response to inputs evidencing such characteristics. Preferably the system is designed to reliably sense the presence of an intruder in multiple zones, to be economical to manufacture, easy to install, to be battery-powered and of a long life.
    Type: Grant
    Filed: February 4, 1980
    Date of Patent: August 3, 1982
    Assignee: Rossin Corporation
    Inventor: John A. Rossin
  • Patent number: 4333094
    Abstract: A free-floating self-contained swimming pool alarm unit in which a hollow housing forms a float structure having an internal chamber within which an audible alarm device is mounted adjacent sound transmitting openings in a top wall of the housing. An upstanding flared chimney surrounds the openings and provides a sound amplifying horn, the outer end of the chimney being provided with a shielding cap. Electronic control is arranged to trigger and activate the alarm device by connecting it to an electric source in the housing in response to the operation of a liquid sensor switch as a result of tilting movements of the housing due to wave disturbances produced by an object or person falling into the pool. Once the alarm is triggered, it will continue to operate until deactivated by an appropriate switch such as a manual switch mounted in an accessible portion of the housing.
    Type: Grant
    Filed: June 26, 1980
    Date of Patent: June 1, 1982
    Assignee: Homexx International Corp.
    Inventor: William E. Osborne
  • Patent number: 4327358
    Abstract: A physical deterrent barrier is utilized as an integral part of an intruder detection sensor that provides surveillance of intrusions in the air space over the barrier. The sensor is a corner reflecting antenna that is coextensive with and mounts on the top of the barrier and is integrated into a barbed wire topped chain link fence by arranging appropriately spaced parallel strands of barbed wire into a V configuration so as to effect an electrical corner reflector at the system operating frequency.
    Type: Grant
    Filed: February 29, 1980
    Date of Patent: April 27, 1982
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Nicholas V. Karas
  • Patent number: 4311889
    Abstract: An alarm device including an alarm switch mounted on the structure of a building that carries walking surfaces such as a floor joist. A switch is actuated upon structural deflection associated with imposition of predetermined amount of weight at the area of the switch as when a person is walking thereon. The deflection of the structure causes relative movement between an electrical contact and an electrically conductive taut wire to energize a circuit which can give an alarm or other indication.
    Type: Grant
    Filed: January 28, 1980
    Date of Patent: January 19, 1982
    Inventors: Jeffrey R. Blanchard, Lawrence J. Themmes
  • Patent number: 4306228
    Abstract: A method and system for evaluating output signals from at least one sound pickup of a security alarm system and for generating an alarm signal by performing the following operations: before the system is placed into operation, determining a first signal frequency range containing the frequency of a signal to be determined and a second signal frequency range containing the frequency of an interference signal; then, during operation, filtering the two frequency range components out of the sound pickup output signals, each component containing a respective one of the frequency ranges, comparing the amplitudes of the two frequency components to one another and generating a difference signal representative of the difference therebetween, and generating an alarm signal whenever the difference signal traverses a threshold value.
    Type: Grant
    Filed: January 7, 1980
    Date of Patent: December 15, 1981
    Assignee: Licentia Patent-Verwaltungs-G.m.b.H.
    Inventor: Gunther Meyer
  • Patent number: 4297684
    Abstract: An intruder alarm for protecting the perimeter of an area utilizes a multimode optic fiber as the deformable sensing element, wherein a length of multimode optic fiber is buried in the ground of an area or perimeter to be protected. As coherent light from a laser is directed through a length of optic fiber, the output light pattern therefrom is speckled. When a deformation of the fiber occurs, even a small amount, the speckle pattern changes and is detected electronically indicating that a disturbance has taken place.
    Type: Grant
    Filed: March 26, 1979
    Date of Patent: October 27, 1981
    Assignee: Honeywell Inc.
    Inventor: Charles D. Butter
  • Patent number: 4286261
    Abstract: A dual signature perimeter detection system utilizing an elongated solenoid ype transducer having a ferromagnetic core as a line sensor is buried in the ground around an area to be protected against intrusion. One end of the transducer is impressed with constant frequency oscillator signals from a signal generator, while a resistance load impedance is connected across the other end of the transducer at the input side of an amplifier used to pass amplified signals selectively to the inputs of either a bandpass type filter or an A.M. detector, or to both simultaneously, then to their related alarms. The line sensor is sensitive to both magnetic and strain stimuli, but the system hereof, which utilizes dual alarm devices, not only provides for determining the type of stimulus creating the signals, but also improves the sensitivity and response uniformity of the transducer.
    Type: Grant
    Filed: September 1, 1978
    Date of Patent: August 25, 1981
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Gilbert F. Wagner, J. Louis Berger
  • Patent number: 4206451
    Abstract: A system for detecting intrusions into a protected area by personnel, vehicles, or other objects, including a sensor capable of detecting magnetic and/or pressure disturbances and a signal processing means for generating an alarm signal when an unwanted intrusion occurs. The signal processing apparatus includes a first band-pass filter for selecting the portion of the signal from the sensor which is within a first frequency range, and a second band-pass filter for selecting a portion of the signal within a second frequency range. Logic circuitry is provided to process the two analog signals from the two band-pass filters using amplitude, signal energy and zero-crossing characteristics of the two signals in a cross-channel relationship to eliminate false alarms which might be caused by disturbances such as lightning, thunder, or wind.
    Type: Grant
    Filed: November 5, 1975
    Date of Patent: June 3, 1980
    Assignee: Honeywell Inc.
    Inventor: Dennis L. Kurschner
  • Patent number: 4189722
    Abstract: The present apparatus is designed to determine the presence of an intruder in a swimming pool by detecting a predetermined change in water level caused by displacement. The surface of the pool water forms the lower boundary of an air filled acoustic cavity, and cavity resonance is excited therein by a sonic transducer coupled to the cavity and also to a signal amplifier, causing the cavity to determine the frequency of oscillation of the feedback amplifier. A rise in water level caused by intruder displacement decreases the vertical dimension of the cavity so that the cavity has a different resonant frequency than before intrusion, and the amplifier therefore oscillates at a different frequency. The predetermined change in amplifier signal output frequency is sensed by an electrical network and converted to an alarm device activating signal to indicate an intrusion.
    Type: Grant
    Filed: November 17, 1977
    Date of Patent: February 19, 1980
    Inventor: Julius O. Lerner
  • Patent number: 4179691
    Abstract: A circuit for an infrared intrusion detector comprising a plurality of receiving directions or regions which are separated from one another and a radiation receiver, at the output of which there appears an electrical signal corresponding to the infrared radiation which is absorbed by all of the receiving directions or regions. The circuit is structured such that an alarm signal is delivered when the received infrared radiation both ascends in a predetermined manner as well as descends in a predetermined manner within a given delay time.
    Type: Grant
    Filed: July 22, 1977
    Date of Patent: December 18, 1979
    Assignee: Cerberus AG
    Inventor: Hansjurg Keller
  • Patent number: 4159473
    Abstract: A charge-sensitive switch is described sensitive to the adjacency of, or transfer of charge from a person, for controlling lamps, appliances, motors, etc. The switch contains an over-current sensor for detecting excess load current, and takes action to shut off the current. It can also switch successive loads, as would be required in a tri-light lamp. The input sensitivity of the switch is adjustable so as to be able to switch in the presence of an adjacent charge, as would be required for proximity detection in a burglar alarm.
    Type: Grant
    Filed: May 2, 1977
    Date of Patent: June 26, 1979
    Assignee: Johnson-Lazare Canada Limited
    Inventor: Miro Senk
  • Patent number: 4149224
    Abstract: A personal security device incorporated into a conventional flashlight for informing a person, by remote control means, who is outside the door of the house, and indicating by a picture, whether it is a man, woman or child, the picture appearing on a view screen of a unit mounted on the flashlight, so that a person is thus cautioned against opening the door, particularly if there is a man outside.
    Type: Grant
    Filed: January 11, 1977
    Date of Patent: April 10, 1979
    Inventors: William G. King, George Spector
  • Patent number: 4141008
    Abstract: A shielded two-wire cable used to transmit signals from one or more remote receivers to a central signal processing unit in an energy-responsive system is simultaneously used to transmit from the signal processing unit to the receivers (a) a signal proportional to the system noise level, (b) a pulsating signal when the system noise exceeds a level indicative of a desired margin of safety, and/or (c) a steady-state signal when an alarm signal is generated by the signal processing unit.
    Type: Grant
    Filed: December 21, 1977
    Date of Patent: February 20, 1979
    Assignee: Detection Systems, Inc.
    Inventor: Richard L. McMaster
  • Patent number: 4118691
    Abstract: A spring within a container is maintained in compression by a first movable pin that extends from the inside to the outside of a container. In response to the first pin being pulled from a set position, a spring drives a hammer against a dispensing button of a tear gas cannister whereby the cannister dispenses tear gas. Additionally, a second pin extends from the inside to the outside of the container. In response to the second pin being pulled from a set position, a switch causes the application of a voltage of a battery to a horn whereby the horn emits sound.
    Type: Grant
    Filed: February 17, 1977
    Date of Patent: October 3, 1978
    Inventor: Ruth E. Sims