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| Number | Title | Issue Date |
| 4255748 | Bus fault detector The present invention comprises computer system equipment useful for detection of faults in data transmission within a computer system. Fault detection is accomplished by monitoring the current flow through a digital signal source means, which is characte... | 03/10/1981 |
| 4251769 | Indicator and limit value alarm device The present electronic indicator or display device is equipped with adjustable upper and/or lower limit value markers to provide a respective alarm if such limit values are exceeded or not reached. The display itself comprises an electronic circuit and op... | 02/17/1981 |
| 4246572 | Detection circuit with hysteresis A battery-powered fire alarm including a smoke detector circuit, a controllable horn circuit and a battery monitoring circuit. The smoke detector employs a pair of complementary field-effect transistor switches with gates respectively connected to an ioni... | 01/20/1981 |
| 4241336 | Method and apparatus for monitoring poly-phase currents in poly-phase equipment A method of and a device for monitoring poly-phase currents in poly-phase equipment, in which a phase signal representative of the current in each phase of the equipment is obtained, the phase signals multiplexed so as to obtain a single multiplexed signa... | 12/23/1980 |
| 4240077 | Thermostat A thermostat monitoring and controlling the temperature of produce ripening within an enclosure and featuring a bridge circuit sensing errors between the actual and desired temperatures in which the desired temperature is selected directly in units of deg... | 12/16/1980 |
| 4238696 | Failsafe electrical circuitry A fail safe control circuit in which an input signal for initiating control of a potentially dangerous system is amplified only if it lies between given limits and also only if electrical power is being supplied to the system. The outputs of the amplifier... | 12/09/1980 |
| 4235181 | Automatic blower control system for inboard marine engines 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 ... | 11/25/1980 |
| 4231026 | Battery discharge level detection circuit A circuit for detecting the discharge level of a long life battery, such as a lithium battery, in which the battery is periodically subjected to an increased load for short durations of time. The periodic increases in load allows the end of battery life t... | 10/28/1980 |
| 4228429 | Alarm system having phase-sensitive bridge circuit An alarm system for detecting a dangerous condition such as the increase in content of or the presence of toxic or inflammable gas in the air and giving a warning signal. The alarm system comprises an AC power supply, a full-wave rectifier connected to th... | 10/14/1980 |
| 4222045 | Capacitive shift fire detection device A capacitive shift fire detection device having a sample circuit and a reference circuit, each circuit having an air capacitor connected to an oscillator and a counter. The presence of particles of combustion in the ambient environment results in a change... | 09/09/1980 |
| 4219702 | Malfunction detector for a dictation system A dictation system having means for providing a signal for indicating when dictation which the system has been made operative to record on a recording medium is not being recorded on the recording medium because of a malfunction of the system or the impro... | 08/26/1980 |
| 4210906 | Transient suppression and detection system with operational indicator means A system for providing the suppression of voltage transients and other electromagnetic interference with positive indication of the operational status of the system. More particularly, a transient suppression circuit is utilized that suppresses and dissip... | 07/01/1980 |
| 4205307 | Device for monitoring the function of electromagnets A first amplifier measures the instantaneous voltage across a resistor, connected in series with the electromagnet of a solenoid valve, as the current increases following energization of the electromagnet. A second amplifier measures the same voltage and ... | 05/27/1980 |
| 4203095 | Monitoring apparatus for direct wire alarm system For monitoring the supervisory current in a communications line between a power source and a protected premises which forms a security protection circuit, monitoring apparatus utilizes sensitive solid state circuitry which appears transparent to the prote... | 05/13/1980 |
| 4201979 | Conveying data signals between relatively rotatable units When high-speed digital signals are transmitted through a slip ring connection between relatively rotatable systems, the slip ring connection is prone to brief interruptions of contact which introduce extra "ones" or "zeros" into the transmitted digital w... | 05/06/1980 |
| 4194195 | Portable liquid level maintenance monitor system for vehicles A monitoring circuit for monitoring a plurality of signals developed by remote sensors which preferably are capacitance probe sensors. The circuit is intended for use with a motor vehicle maintenance system employing capacitance probes to detect low and s... | 03/18/1980 |
| 4173750 | Incandescent lamp monitoring device A monitoring device for monitoring incandescent lamps, especially in motor vehicles, is provided. A measuring resistor is connected in series with an incandescent lamp to be monitored. Means for monitoring the voltage drop at the measuring resistor are pr... | 11/06/1979 |
| 4163971 | Systems for displaying analog values In the system disclosed a driving circuit repeatedly scans along a plurality of aligned electrodes in an enclosure filled with ionizable gas, by sequentially grounding the aligned electrodes and repeating the process cyclically. Within each cycle, a pulse... | 08/07/1979 |
| 4152656 | Apparatus for monitoring an AC variable Apparatus for the rapid monitoring of an alternating (a-c) variable with respect to amplitude, frequency and phase which includes a generator circuit for forming, from an actual a-c voltage imaging the monitored a-c variable, a reference a-c voltage of pr... | 05/01/1979 |
| 4149160 | Multi-input signal comparator and indicator circuit A multi-input signal comparator and indicator circuit for comparing a plurality of signal levels with a reference level and an indicator circuit arranged to respond to a comparator output signal for indicating an error in any of the comparator input signa... | 04/10/1979 |
| 4110687 | Dual threshold logic probe A logic probe includes a first lamp for indicating an input voltage level above a first predetermined magnitude or upper threshold, a second lamp for indicating an input voltage below a second predetermined magnitude or lower threshold, and a pulse lamp f... | 08/29/1978 |
| 4109234 | Anti skid fault detection circuit Fault detection circuit which is intended to be included in an anti-skid control system for a braking system of a motor vehicle. The fault detection circuit is coupled between the sensor coil and tachometer portion of the anti-skid control system and dete... | 08/22/1978 |
| 4084156 | Voltage monitoring circuit Circuit for indicating when a voltage indicative of a condition, such as the presence of smoke, changes to a value outside of a given voltage range. It includes an oscillator which oscillates in response to a value of voltage within said range and which s... | 04/11/1978 |
| 4065758 | Alarm detector responsive to rate of change of a monitored condition A physical quantity such as temperature, infrared radiation or smoke is detected by means of a conversion device for emitting an alarm signal whose amplitude is representative of the intensity of the physical quantity. The detector comprises a unit for me... | 12/27/1977 |
| 4052717 | Battery condition monitoring method and apparatus A battery condition monitoring device which senses battery terminal voltage and creates a function thereof and tests that function against predetermined criteria and determines battery condition as a result of such tests. Furthermore, the invention operat... | 10/04/1977 |
| 4032853 | Overdrive detector for radio frequency amplifier A relatively simple, inexpensive, effective circuit for detecting overdriving of a radio frequency amplifier by an amplitude modulated signal. The input and output signals of the amplifier are coupled to peak detectors. A light emitting diode which provid... | 06/28/1977 |
| 4032094 | Control of positioning system authority over aircraft control surfaces as a function of surface movement rate Method and apparatus for controlling aircraft flight control surfaces. A signal indicative of control surface movement rate is provided and tested for level and duration. When said rate indicative signal exceeds a predetermined level for a predetermined t... | 06/28/1977 |
| 4020479 | Fire detector An improved early warning fire detector of the ionization type is provided wherein detection circuitry having adjustable sensitivity is connected to an ionization chamber responsive to products of combustion. A supervisory circuit monitors the unit to ass... | 04/26/1977 |
| 4017724 | Apparatus for measuring battery depletion by monitoring reductions in voltage The apparatus comprises means for sensing reductions in the output terminal voltage of the battery due to varying load conditions and producing a signal in response thereto during the time that the terminal voltage is below a threshold value. The apparatu... | 04/12/1977 |
| 4010456 | Low battery voltage indicator for a portable digital electronic instrument The output voltage of a battery in a portable digital electronic instrument is compared with an internal voltage reference. When the battery voltage falls below the reference voltage, the true decimal point of the number being displayed is not illuminated... | 03/01/1977 |
| 4005365 | Voltage comparator and indicating circuit A device including a voltage indicator circuit has the capability of indicating positive, neutral and negative voltages with respect to a reference voltage. Three indicator circuits are mounted on a single substrate. Each indicator circuit energizes a res... | 01/25/1977 |
| 3999124 | Reference quantity and unknown quantity comparator A method of and apparatus for determining when an unknown quantity is within a desired range of a reference quantity. The apparatus includes a dual slope integrator which integrates the reference quantity and the unknown quantity and discharges the result... | 12/21/1976 |
| 3997869 | Speed limit passing indicator A speed limit system providing a passing of a given limit is disclosed. The speed-limit indicator comprises a frequency-voltage converter receiving at its input a signal which is produced by a sensor indicative of vehicle speed. A detection circuit compri... | 12/14/1976 |
| 3991553 | Low voltage battery indicator for a solid state watch Disclosed is a solid state wristwatch having a digital light emitting diode display and a low battery voltage circuit for actuating the display to indicate the approach of battery failure. The battery voltage sensing circuit draws power only when the disp... | 11/16/1976 |
| 3991302 | Method for detecting and isolating faults in digital and analog circuits with multiple infrared scanning under conditions of different stimuli A method for detecting faults in digital and analog circuits including the steps of thermally stabilizing the circuit, applying electrical stimulus to the circuit for a predetermined time period, scanning the circuit to determine the infrared response, ap... | 11/09/1976 |
| 3987341 | Open neutral protection An artificial neutral voltage derived from the voltages on both energized lines of a three-wire, single-phase energy supply system is compared to the voltage on the neutral line. Comparator means energize interrupter means to cause the cessation of a curr... | 10/19/1976 |
| 3979657 | Battery monitor with automatic scale and recycle prevents A monitor for disabling a selected operative function of the battery powered vehicle when the battery reaches a predetermined discharge state is disclosed. The discharge state of the battery is determined by continuously monitoring the terminal voltage of... | 09/07/1976 |
| 3974403 | Digital data transmission system A driver circuit for a digital data transmission system is provided with a transistor current limiting network, the network being bypassed by a capacitor. The network is selectively supplied with a disabling signal via another transistor to disconnect the... | 08/10/1976 |
| 3967133 | Power supply means A power source particularly for use in remote locations which can be operated off of conventional sources of power such as off a battery source, said power source including means for distinguishing between different voltages and including means to indicat... | 06/29/1976 |
| 3964276 | Knitting error detecting apparatus for circular knitting machine A circular knitting machine having a device for electronically issuing a pattern-forming command is provided with a needle selection verification pulse detector. The needle selection verification pulse detector produces a needle selection verification pul... | 06/22/1976 |
