Abstract: A burglar alarm has a sound generating circuit which is actuated when the two magnets are moved away from each other. The sound generating circuit includes two coils of wire wound on a common core, and a permanent magnet hammering device which is actuated by the coils for sounding. When the two magnets are moved away from each other, a switch closes so that intermittent current can flow through one of the coils which repels the hammering device for sounding and releases it under the action of the other coil.

Abstract: A monitoring system for the notification of locations external to the area being monitored of a prolonged absence of motion within the area being monitored is disclosed consisting of a clock, an electronic counter designed to record the pulses emitted periodically by the clock and to signal an alarm trigger when a pre-programmed number of pulses are recorded, and reset means such that if activated the counter will return to zero thereby preventing activation of the alarm trigger. Also, this system uses circuit means incorporating a photoelectric cell to automatically increase the pre-programmed number of pulses necessary to cause activation of the alarm trigger during periods of darkness and to automatically return the counter to its original pre-programmed condition with the presence of light.

Abstract: It is herein disclosed a closed circuit alarm system comprising a number of alarm detectors, which system comprises an amplifier coupled through condensers to a first alarm relay and which is further coupled to a second relay the arrangement being such that when an electrical signal is generated in the first relay, in response to the bridging of any of the alarm detectors, such electrical signal is amplified and applied to such second relay thereby producing by said second relay an electrical signal which is applied to the first relay which then operates for putting the alarm device in the circuit.

Abstract: A monitoring system for use as an intruder alarm. The system which is designed to reduce the likelihood of generating false alarms, e.g. alarms generated in the absence of an attempt to break in to premises protected by the system but in the presence of some other occurrence, includes a sensor circuit having at least one set of normally-closed contacts coupled in series between terminal means for coupling the circuit to a source of current and output means coupled to the sensor circuit for providing, in use, a first output signal upon actuation of a set of contacts for a predetermined time interval the length of which may be varied as desired. The system includes pulse generating means for providing the first output signal in the form of pulses, timing means for defining said interval and counting means for counting the output pulses during the said interval and for providing a further output signal when the number of pulses counted in the said interval equals or exceeds a predetermined value.

Abstract: A three wire circuit for supplying electrical power to active, power-consuming detection devices and communicating electrical signals providing supervisory information and fire alarm information to a control panel. Two wires supply electrical power the third carrying supervisory and alarm signals. Passive non-power-consuming detectors may also be utilized on said circuit. Detection devices switch the positive power to the signal wire in the event of an alarm and an end-of-line device switches the negative power to the signal wire through a current limiting device as a supervisory signal when conditions are normal. The end-of-line device measures the voltage on the power supply wires and opens its switch when the voltage falls below a specific level to indicate trouble. The circuit can carry an alarm signal in spite of and overriding a supervisory signal.

Abstract: Alarm system in which the latch plate of the door jamb is movable to contact a striker plate spaced and insulated therefrom to close an alarm circuit. The system is so designed that if an attempt is made to force the lock, the latch plate which is resiliently mounted will move and thus make contact with the striker plate. A contact relay and thermal relay are incorporated in the alarm system in such a way that the alarm can be timed to signal for a predetermined length of time after which it will automatically shut off. As soon as the alarm signal has stopped the system is ready to signal again.

Abstract: A temperature indicating device for use with a conduit system wherein a fluid material is moved and is weighed by a continuous weighing mechanism comprising (a) an adapter which is partially shaped to be detachably connected to said continuous weighing mechanism and incorporated into said conduit system on that portion of said continuous weighing mechanism where the fluid material passes therefrom, said adapter being provided with a nipple in the side wall thereof; (b) a sensing probe which is slideably mounted within said nipple, said sensing probe extending throughout the entire length of said nipple and into the interior portion of said adapter whereby the sensing probe will be in thermoconducting relation with the fluid material moving through said adapter; (c) a control module containing input and output circuits, disposed remotely from said sensing probe and interconnected therewith by suitable electrically conductive means, said control module adapted to receive a signal from said sensing probe via sai

Abstract: A solid state electronic alarm circuit including means for sensing a predetermined change in a parameter such as the temperature in a freezer or the like from a predetermined safe limit and means for generating an audible alarm in response thereto.

Abstract: A rotatable element for a display element is constructed of an open ring which supports a display surface resiliently bent from its unstressed attitude and held in such position. The element is designed to be pivotally mountable on an axis generally parallel to the mean plane of the display surface.The element is preferably magnetically operable by an exterior magnetic field and the element carries a magnet defining a field transverse to the pivotal axis.The exterior field for the rotatable element is preferably provided by a coil wound core resiliently mounted on the support surface for the element.The support surface provides brackets for location on each side of the element position and designed to receive a shaft mounting such elements.

Abstract: A vibration sensitive electrical alarm system comprising an electrically conductive pendulum means swingably suspended from an axle member, a pendent body pivotally attached to said axle and having an electrically conductive projection secured to it extending in the direction of said pendulum means, the arrangement being such that when the pendulum means is set into motion, it is adapted to touch said projection whereby an alarm is activated.

Abstract: A device for signaling a patient when a predetermined load is placed on the patient's foot comprises a resilient foot pad having a toe end and a heel end and adapted to substantially cover the inner sole of a shoe. A resilient liquid filled tube is mounted within the pad with the tube extending from adjacent the toe end to adjacent the heel end of the pad. A signaling device is controlled by a pressure responsive means in communication with the liquid in the tube for the actuation of the signaling means at a predetermined pressure of said liquid.

Abstract: A three terminal coulometric timer cell is provided having two terminals available to detect continuity of an anode filament that is ruptured after a predetermined time period by plating away upon a cathode cup-like container. Connected across said two terminals is a light emitting diode to visually indicate the end of the time period. Simplified circuit configurations requiring only the cell, two resistors and the light emitting diode are provided with variations permitting AC -- DC operation, reliable high voltage operation, low operating power and temperature stable operation.

Abstract: A physiotherapy timing and control device for instructing a patient to perform a prescribed program of exercise including a series of "exercise" periods each followed by a "rest" period at the start of which the patient is required to read and record his pulse, includes a spring-wound timer having a dial time-graduated in intervals corresponding to the periods of the exercise program to provide visual guidance concerning the progress of the program, and signal generating means actuable in response to operation of the timer for generating an audible signal of relatively short duration at times corresponding to the start of an exercise period, and an audible signal of longer duration at times corresponding to the start of a rest period. In the preferred embodiment the longer audible signal has a duration of fifteen seconds so that a pulse count observed during the signal when multiplied by four gives the patient's pulse rate in beats per minute.

Abstract: A three-wire alarm system is disclosed which features a plurality of plug-in strips each carrying a plurality of three-connector receptacles. These strips may be interconnected one to the next and to a battery-powered alarm box by identical jumper cables with three-pinned plugs. Other cables with identical plugs are fastened to valuable items which a merchant desires to display. When these items are placed on display, they are plugged into a nearby plug-in strip. The items may be plugged in without setting off the alarm; but removing any plug or cutting, shorting, or breaking the cables produces an alarm that can be turned off only with a key.The three-contact receptacles of the invention contain a spring that (1) serves to interconnect two of contacts when the receptacle is not in use, (2) contacts the pin mating with the third contact when a plug is inserted, and (3) is dragged by that pin into contact with one of the other contacts when the plug is withdrawn thereby causing an alarm.

Abstract: A light emitting diode indicator assembly for a multiple pushbutton array has a printed circuit board with a plurality of circuits thereon, each circuit having a connection position for a light emitting diode; a spacer attached to the printed circuit board with a location for a light emitting diode coincident with a related connection position; a light emitting diode at each location with leads connected to the related circuit; a lens over each diode; and a bezel having a first row of apertures with a lens situated in each aperture, and a second row of apertures with a pushbutton in each aperture, the bezel and spacer having interengaging formations whereby the spacer is inserted into a recess in the bezel and the formations engaged by lateral movement of the spacer relative to the bezel. There can be more than one row of lens containing apertures, and also more than one row of pushbuttons containing apertures.

Abstract: Circuitry is disclosed that monitors the frequency at which a heater controller applies pulses to a heater to determine if the heater controller is operating properly. If the heater controller fails to generate a pulse in a selected interval, the circuitry generates a signal that activates an alarm and interrupts the operation of a machine that is processing material heated by the heater.

Abstract: A flame detection system comprising two light responsive photovoltaic photocell sensors in combination with corresponding light filters, a photovoltaic sensing amplifier, a control amplifier, and a power source. The photocell/filter combinations are responsive to spectral energy in two different regions of the spectrum, said regions being such that illumination from a hydrocarbon flame causes a reversal in voltage polarity of the signal from the pair of photovoltaic photocells. The photovoltaic photocells are serially connected in voltage opposition and the voltage produced by the combination is applied as an input coupled to the sensing amplifier. The latter is arranged and configured to respond to a selected voltage polarity generated by the photovoltaic combination, when illuminated by a hydrocarbon flame, by providing a control signal to the control amplifier. The control amplifier is typically coupled to a relay and/or solenoid valve which controls the turn-on of a fire alarm and/or extinguishing means.

Abstract: An electronic security system adapted for use in a controlled area such as a retail store and employing a multi-frequency resonant tag circuit having distinct frequencies for detection and discrimination. An electromagnetic field is provided within the controlled area at a frequency which is swept through a range including the detection frequency of the resonant tag circuit. In the presence of a tag circuit within the controlled area, pulses are detected by a receiver which includes noise rejection circuitry for discriminating true signals from noise. The noise rejection circuitry is sensitive to expected signals and operative to discriminate true signals from noise on the basis of several different criteria, resulting in substantially reduced false alarm actuation.

Abstract: A fire alarm and protection booth having means therein for signalling an alarm to a fire station and/or police station as well as providing refuge in the case of an emergency. The booth comprises an enclosure having a door and a foot treadle which are coupled to electrical switches adapted to provide input signals to a solid state control circuit which upon the actuation of an alarm switch, sets off an alarm as well as detains the person in the enclosure for a predetermined period. An emergency switch is also included which when actuated locks the door during the time the emergency switch is continuously pressed. In the event that the alarm switch is subsequently actuated, the emergency switch is overridden. The solid state control circuit is further operative to defeat any attempt to compromise the alarm system and thereby render the apparatus fool-proof and tamper-proof.

Abstract: A control device repeatedly starts operation of a portable machine by detecting the movement of a hand on a watch mechanism and producing a first start signal to start operation of one portion of the portable machine. A delay arrangement then produces a second start signal to actuate the remainder of the portable machine. A timing device, actuated by the first start signal, stops operation of the machine before occurrence of another first starting signal.