Abstract: An automatic bypass switch comprising an electronic switch circuit responsive to voltage signals generated by the delay circuit and armed status of an electronic alarm system. The output of the bypass switch is connected to one or more detection circuits so as to shunt or prevent activation when the control has been armed until the delay circuit has been activated. From this time until the panel has been disarmed and rearmed again, the controlled detection circuit(s) is active and not shunted.

Abstract: A security-ensuring apparatus capable of operating in an unmanned security-ensuring operation mode, a manned security-ensuring operation mode, or a management operation mode having at least a maintenance mode or a patrol mode, the apparatus having an operation mode-switching unit, an emergency-detecting unit for detecting an emergency or abnormality which has occurred in a predetermined area, and a control unit for permitting transmission of an emergency or abnormality signal to a central monitoring station on the basis of discrimination of the current operation mode of the apparatus.

Abstract: A low fuel indicator system 10 for a motor vehicle comprises a light-emitting indicator 12 which is energized or de-energized by an output signal derived from a voltage comparator 14 which receives a reference voltage from a reference voltage source 20 and a variable voltage signal from a time delay circuit 22, which variable voltage signal is derived from a voltage signal generated by a fuel level sensor in a fuel tank of the vehicle. The light-emitting indicator 12 is energized when the fuel level in the fuel tank falls below a predetermined low level, and time delay circuit 22 operates to isolate the voltage comparator 14 and light-emitting indicator 12 from temporary variations in fuel level produced by "fuel-slosh" in the fuel tank caused by variations in the motion or orientation of the motor vehicle.

Abstract: Discrimination apparatus for use in a fire and explosion detection and suppression system which includes plural detectors and suppression apparatus operated thereby and including apparatus for sensing detection by a first number of detectors within a predetermined time period and providing an output signal only when the first plurality of detectors detect within the predetermined time period and apparatus operative in response to the output signal for inhibiting operation of the suppression apparatus.

Abstract: A memory device for lighting control purposes, including, for example a battery. The charge of which is controlled by at least one photodetector, which receives light from a lighting means when the latter is in operation. Charging the battery takes place during an operating period of the lighting means. When the latter is not operating, the battery discharges into a light emitting diode. Thus, the information concerning the satisfactory operation of the lighting means is stored for a certain time and after said operation it is possible to check that the latter has taken place. The device has applicability to the control of a public lighting system.

Abstract: Low oil level in an engine crankcase is detected immediately after the ignition switch is turned on by a circuit including the ignition switch, an oil level sensor and a coolant temperature sensor wherein a control circuit generates an output if a low oil level signal is present when the ignition switch is turned on. An enabling circuit allows an output only if the ignition switch has been turned off for a sufficient time period to allow oil drain back to the crankcase. A time delay circuit responsive to coolant temperature and the ignition switch prevents a control circuit output after the ignition switch is turned off for a short period when the temperature is high and a long period when the temperature is low.

Abstract: A sensing and display system for a refrigerator includes a plurality of sensors which are sequentially monitored at a first rate in order to determine whether certain conditions in the refrigerator are within predetermined ranges. If the sensed conditions are within their ranges, a first plurality of visual indicators are sequentially energized at a second rate and a separate indicator is continuously energized to indicate normal operating conditions. If the system detects that one or more of the sensed conditions are not within their ranges, the first plurality of indicators and the separate indicator are de-energized, and one or more of a second plurality of indicators are energized to inform the user of the existence of one or more abnormal operating conditions. The system delays an abnormal condition indication, such as an overtemperature condition, until the condition has existed for a predetermined period of time.

Abstract: A fire alarm control system in which an electronic switch circuit is responsive to an increase input current signal generated by one or more fire detection devices. A local alarm is connected to the electronic switch circuit to indicate an alarm state. A delay timer circuit is connected to the electronic switch circuit and operated thereby to activate a remote alarm after a predetermined time delay. A manual two-position switch is movable to a silence position from its normal position within the time delay to disable the local and remote alarms and movable back to its normal position to cut off power to the detection devices and electronic switch means to unlatch the alarms. A further pair of manually operable switches are provided to instantaneously reactivate the disabled local and remote alarms when the two-position switch is in the normal position.

Abstract: A Simplified Intruder Detector is disclosed that incorporates a compact, unique optical system and detector array, including pyroelectric elements mounted in an adjacent, facing relationship. This causes radiation passing through one element to immediately pass through the adjacent element, thereby ensuring that white light, to which the detector elements are not particularly responsive, will generate substantially the same electrical signal in both elements. The electrical system preferably includes a unique power test feature to regularly insure that the system is adequately powered, but only after an intruder has been detected, thereby avoiding nonresponse to an intruder as well as false alarms.

Abstract: In a central station alarm system the alarm sensors associated with a particular subscriber's premises are monitored by a local control unit associated with those premises and controllable by the subscriber. The local control unit automatically reminds the subscriber when he is supposed to close the premises and turn on the system. The local control unit allows the subscriber to change his expected closing time. The local control unit may also perform various other functions such as automatically cutting off power to low priority alarm sensors during a prolonged power failure, automatically cancelling any audible alarm indication silence commands when there are no alarms to silence, and automatically forming a bridge connection between the remote ends of two communication circuits when there is a break in either circuit.

Abstract: In an electrical power transmission system, transmitter-receiver pairs at stations which communicate with similar pairs at other stations to block tripping of circuit breakers or for other control functions are periodically tested. An electrical circuit periodically activates a transmitter to send a test signal from a first station over a power line to a receiver at another station in the system. The receiver at the other station activates the associated transmitter in response to receipt of the incoming signal to send a signal back to the receiver of the first station. If this cycle is not completed in a specified time, indicating loss of communication between the two transmitter-receiver pairs, an alarm is activated.

Abstract: A motion detection system is disclosed which utilizes a lens or other imaging device to be responsive to motion in a particular field of view in a room, for example, and pass illumination to a photocell. The photocell or a screen in front thereof establishes image distortion so that there is a nonuniform electrical output from the photocell upon motion of objects in the given field of view. The nonuniform electrical output establishes pulses which are passed to a timer and continually resets the timer so long as there is motion detected. Upon discontinuance of any motion in the field of view, no further pulses are passed to reset the timer, and the timer times out to de-energize an electrical load. This may be an electrical lamp illuminating the field of view, or it may be an electric soldering iron or typewriter which is de-energized when the person has left the room.

Abstract: In a central station alarm system the alarm sensors associated with a particular subscriber's premises are monitored by a local control unit associated with those premises and controllable by the subscriber. The local control unit automatically reminds the subscriber when he is supposed to close the premises and turn on the system. The local control unit allows the subscriber to change his expected closing time. The local control unit may also perform various other functions such as automatically cutting off power to low priority alarm sensors during a prolonged power failure, automatically cancelling any audible alarm indication silence commands when there are no alarms to silence, and automatically forming a bridge connection between the remote ends of two communication circuits when there is a break in either circuit.

Abstract: A smoke detector includes a sensing unit which has a power terminal adapted to receive electrical energy. A timing device in the smoke detector includes a switch, a timer and a manually operable device. The switch is coupled to the power terminal for interrupting current thereat. The timer can operate the switch to cause interruption of current at the power terminal for a predetermined interval. The manually operable device can actuate the timing means and start its predetermined interval.

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.

Abstract: Apparatus is provided for a wall mounted thermostat to accept and convert manually generated instructions to binary encoded electronic impulses to control ambient air conditions in the environment in which the thermostat is located. The parameters of operation include a building heating control which reduces the desired ambient temperature at night, beginning at a prescribed time and returning to a higher daytime level at a different prescribed time. The system may also adjust desired temperature depending upon humidity conditions and alter the timing of heating and air conditioning control by predicting when a desired temperature will be reached in order to avoid overshoot. The system includes a liquid crystal or light emitting diode display and communicates with a power source and with heating and air conditioning switches such as relays or contactors.

Abstract: In a vehicle alarm system there is provided apparatus for producing a digital control signal that defines a command to initiate a timing operation such as an entry delay. The apparatus comprises a transducer, preferably including a piezoelectric device, for generating an electrical waveform that, while the vehicle is undergoing vibration, has an acceleration-representing analog signal component. The apparatus further comprises threshold-setting circuitry responsive to the electrical waveform for causing the initiate-timing command to be given when the acceleration representing signal component exceeds a predetermined threshold.

Abstract: A smoke alarm having means for detecting smoke and producing a signal in response to the detected smoke is provided with a manually-actuated control which cooperates with the signal producing means to temporarily deactivate the same and to automatically reactivate the same after a predetermined time delay. A temperature responsive override switch is provided to actuate the signal in the event of a fire during the time delay. Thus, a homeowner is able to temporarily deactivate the smoke alarm, such as duringcooking, parties, showering, etc. to thereby prevent the alarm from going off in response to non-fire conditions.

Abstract: The smoking elimination guidance system of the invention, which is preferably incorporated in a cigarette lighter, includes a timer which is responsive to each operation of the cigarette lighter automatically to initiate a new predetermined timing period during which only a single cigarette is to be smoked. Indicator means visible on the outside of the cigarette lighter indicate to the user when the end of the current timing period is reached. Timing period modifying means are provided for automatically at various times progressively increasing the timing period initiated by the operation of the cigarette lighter, such as by a predetermined fixed percentage. Before the timer starts into operation, a smoking elimination program suitable to the user is selected automatically during a measurement period when the user's cigarette smoking rate is determined.

Abstract: An alarm device responsive to vibration includes a unitary housing in which is disposed an SCR for connecting an alarm signal to an associated source of power, the gate of the SCR being connected to a pendulum and ring assembly with the pendulum being normally suspended within the ring out of engagement therewith but which moves into engagement with the ring when the housing is subjected to vibration to apply power to the SCR gate so that the SCR conducts to actuate the alarm signal for indicating the application of a vibration to the housing or a supporting structure on which the housing is mounted. The alarm device may also include timing circuitry which deactivates the SCR after a predetermined period of time.

Abstract: In an alarm control system for protecting a premises, a four conductor bus line leading from a master control station is extended about the interior perimeter of the premises. Sensors positioned near each port of entry to be monitored are connected in parallel relationship to the bus line, as is at least one remote station for manually arming, disarming or activating the system. Each sensor comprises a biased reel carrying line secured to window, door, screen, or the like. Disturbance of a sensor causes a magnetically responsive switch therein to generate a pulse triggering circuitry within the control station to activate the desired alarm device for a predetermined period of time. The system then resets automatically to an armed or ready condition to continue protecting the premises against subsequent intrusions. Preferably, the lines in the sensors are of a thermoplastic material so that the system is also activated by abnormally high temperature in the event of fire.

Abstract: A system for monitoring the liquid level in containers such as boilers and tanks. An electrode inserted into the container completes a path through the liquid when the liquid is at or above a predetermined level. When the liquid falls below the level, the path is opened. If the open path persists uninterruptedly for a timed period, an output device such as a relay is energized (or deenergized, if desired) to signal the low fluid level. The circuit path is powered at a low AC level from an AC source which also powers the output device. The low level AC in the circuit path to the liquid minimizes electrolytic and other problems within the container. The low level AC periodically resets a timing device within a direct current monitoring circuit before the expiration of the timed period, as long as the circuit path through the liquid remains closed. The output device is an optical coupling device isolating the output device from the timing device and from the low level AC path.

Abstract: A scram signal generating circuit for nuclear reactor installations monitors a flow signal representing the flow rate of the liquid sodium coolant which is circulated through the reactor, and initiates reactor shutdown for a rapid variation in the flow signal, indicative of fuel motion. The scram signal generating circuit includes a long-term drift compensation circuit which processes the flow signal and generates an output signal representing the flow rate of the coolant. The output signal remains substantially unchanged for small variations in the flow signal, attributable to long term drift in the flow rate, but a rapid change in the flow signal, indicative of a fast flow variation, causes a corresponding change in the output signal. A comparator circuit compares the output signal with a reference signal, representing a given percentage of the steady state flow rate of the coolant, and generates a scram signal to initiate reactor shutdown when the output signal equals the reference signal.

Abstract: A moisture responsive switch is employed for controlling the operation of a fluid operated sprinkling system or the like. The moisture responsive switch provides adjustable time delay means to prevent sprinkler flutter due to intermittent rain fall. Switch recovery time delay means may be adjusted to simulate irrigation evaporation conditions of local geographical terrain. Signal alarm means are provided that signal during precipitation independently of sprinkler system control by the moisture responsive switch.

Abstract: A photosensitive alarm system is provided which produces an alarm signal upon exposure to ambient light for protection of cash drawers, file cabinets, and shipping or storage containers from unauthorized intrusion. The alarm system includes photosensitive arming and trigger circuits which allow the system to become armed when placed in darkness and to be subsequently triggered when exposed to the ambient light. The arming and trigger circuits include separate photocells which are arranged to draw a minimal current to allow a DC battery to be used as a power source for an extended period of time without need for recharging or replacement. Preferably, the alarm system includes a warning circuit capable of producing different output signals in response to multiple exposures of the trigger circuit to the ambient light to indicate the number of intrusions and a clock circuit for indicating the time and date of the initial intrusion into the protected area.

Abstract: An alarm system including an alarm which is actuated when a sensor such as a microphone detects an emergency condition. In one embodiment the output of the microphone is fed through a filter circuit tuned to frequencies characteristic of breaking glass. In conventional systems failure of the microphone may remain undetected but in the system of the present invention an alarm is instituted when the sensor detects any emergency signals and when the sensor fails to detect a reference signal. The reference signal is produced at regular intervals but the alarm instituting means includes a delay and is operable to switch off the reference signal within the delay period to avoid false alarms.

Abstract: A control system for automatic actuation of an exhaust blower associated with an internal combustion inboard marine engine. The control system includes a starter interlock circuit which prevents engine starting for a predetermined period of time to allow the blower to exhaust explosive fumes from the engine compartment and a low speed actuation circuit which operates in response to detection of engine speed below a predetermined level to actuate the exhaust blower. Also included is a emergency override of the starter interlock circuit.

Abstract: A multiple sensor intrusion alarm system including a central controller which communicates with a plurality of sensors over a single, interconnecting cable. The controller periodically polls each of the sensors, and in response to this polling signal, each sensor returns a signal indicating its status. The absence of a return signal from a particular sensor indicates to the controller that the sensor is malfunctioning or has been tampered with. In a preferred embodiment, the interconnecting cable is a single, two-conductor cable. The controller may also be connected to an alarm panel or remote monitoring station to indicate the presence of an alarm condition.

Abstract: The wireless alarm system comprises a portable wireless transmitter assembly adapted to be concealed on the person, a radio receiver and signal decoder for receiving a coded wireless signal transmitted by the radio transmitter, an adjustable timer and signal relay means for relaying the wireless alarm signal received by the radio receiver on to personnel alerting means a predetermined period of time after the wireless alarm signal is received by the radio receiver, and personnel alerting means activated by the alarm signal received from the adjustable timer and signal relay means.

Abstract: A switch connected to a power source is closed automatically in response to a vehicle being conditioned for travel and is opened in response to the vehicle being stopped. First and second apparatuses deliver first and second electrical signals, respectively, to a switching device in response to the switch being closed. The switching device is rendered conductive for connecting the power source to an alarm for energizing the alarm when either one or both of the first and second signals is delivered thereto. The switching device is rendered nonconductive for deenergizing the alarm in response to neither of the signals being present. A timer stops delivery of the first signal to the switching device only after the first signal has been delivered to the switching device for a predetermined period of time. A manual override is provided for manually selectively stopping delivery of the second signal to the switching device.