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Class 307/653 - Flame responsive (e.g., flame acts as a rectifier in circuit)


Subclass of Class 307 - Electrical transmission or interconnection systems
Definition: Subject matter wherein a control or detecting means is constituted
No. of patents: 22
Last issue date: 05/02/1989


NumberTitleIssue Date
4827133Infrared space surveillance detector circuit
A circuit layout for an infrared space surveillance detector with a sensor and a field effect transistor following the sensor. An operational amplifier with a negative input is connected to the drain electrode of a field effect transistor. The output sign...
05/02/1989
4710125Safety device for oil burner
A safety device for an oil burner is disclosed which is capable of carrying out the detection of flame by means of a DC flame current obtained due to the rectification of flame to detect the abnormal combustion in the oil burner. The safety device include...
12/01/1987
4672324Flame protection circuit
A flame control circuit becomes a flame protection circuit when the whole circuit is also controlled with respect to correct operation. A final output signal 32, "presence of flame", is supplied only if a flame 6 is present and the circuit operates correc...
06/09/1987
4599568Electrostatic afterburner light-off detector
A light-off detector for an afterburner of a gas turbine jet engine comprises an afterburner flameholder (24) electrically insulated (70) from an attached igniter (38) and insulated from other engine parts by means of non-electrically-conductive support r...
07/08/1986
4591725System for amplifying all frequencies detected from a flame detector
A fail-safe, self-checking flame monitoring circuit is provided without the use of a mechanical shutter in which a photodetector provides a signal corresponding to flame intensity (including flicker), an amplifier amplifies the signal, the amplification i...
05/27/1986
4538137Fire detector
In a fire detector that includes a sensor for producing an output voltage corresponding to smoke concentration, temperature, etc., there is provided a charge-and-discharge circuit to be reset by the turning ON of a switching circuit which is made ON at a ...
08/27/1985
4527125Flame detecting apparatus
A flame detecting apparatus used in a combustion control apparatus for a water heater provided with a gas burner comprises a pressure switch serving as means for detecting presence or absence of flame and a voltage comparison circuit serving as means for ...
07/02/1985
4507702Relay controlled load
There is provided a control unit for controlling the operation of a fuel valve. The control unit includes a first relay and a second relay. The first relay and the second relay are connectable in series and oppositely actuable. The first relay is actuable...
03/26/1985
4436505Device for detecting flame in open-type combustor and oxygen density of indoor air
A device for detecting the presence or absence of flame in a combustor and an oxygen density of room air used to operate the combustor. An ion current detecting sensor increases a flame ion current value in the combustor to an ion current value at which e...
03/13/1984
4412809Oxygen density detecting device in combustor
An oxygen density detecting device for a combustor in which individual adjustment of reference levels for each combustor is not necessary. A memory device stores a reference ion current value from a sensor disposed in the combustor for a predetermined per...
11/01/1983
4307305Precision rectifier circuits
A precision rectifier circuit includes two differential amplifiers each having a negative feedback path including a diode. Two pnp transistors have their base-emitter paths connected in parallel with the respective diodes and their collectors connected to...
12/22/1981
4300099Fire detecting system
A fire detecting system which is capable of successively controlling the forecasting of a fire, setting off alarms and activating fire-extinguishing equipment. The system includes a detector adapted to produce an electric impedance corresponding to an amo...
11/10/1981
4280184Burner flame detection
Method and apparatus for evaluating the quality of a flame in response to outputs from a flame sensor. The present invention includes a method and apparatus in which output pulses from a flame sensor are continuously counted.The number of pulses is accumu...
07/21/1981
4245977Method and apparatus for hydrocarbon flame ignition and detection
A method and apparatus for hydrocarbon flame ignition and detection is disclosed utilizing a pair of flame-detecting electrodes positioned at the flame site in contact with the flame and in a spaced-apart relationship to accommodate, in the gap therebetwe...
01/20/1981
4177033Flame detection arrangements and the like
A circuit arrangement for utilizing the "flame (or hot gas) rectification" effect in an air gap is provided in which the air gap is defined between electrodes one of which is connected to a source of A.C. and the other of which is connected to earth or ot...
12/04/1979
4168949Flame signal stabilization circuit
A flame rectification system is disclosed wherein a flame rod is used to detect the presence of a flame to control a relay or solenoid operated valve. Upon the initial indication of a flame, a pulse generating circuit momentarily overrides the flame rod s...
09/25/1979
4157506Flame detector
A method and apparatus for processing signals produced by a flame detector. A phase-locked loop is used to generate a binary indication of whether the signal from a flame probe is within a predetermined frequency band. A signal indicative of the average a...
06/05/1979
4146803Fire-responsive control device utilizing thyristors
In a thyristor fire-responsive control device including a fire detector which has a thyristor as output switching means, a control circuit is responsive to the detector. A controlled apparatus is responsive to the detector through the control circuit for ...
03/27/1979
4034235Circuits
This invention relates to a circuit for monitoring the presence of a flame of a gas burner, comprising a probe means connectible to a source of alternating signal and locatable in a combustion area of the flame for applying said alternating signal across ...
07/05/1977
3995221Flame responsive system
A flame responsive system includes a flame sensor, flame signal generating circuitry responsive to the flame sensor and flame signal inhibiting circuitry also responsive to the flame sensor. A fast filter and a slower filter are coordinated so that total ...
11/30/1976
3987319Radiation-activated sensor
A sensing system for use in a remote location which detects electromagnetic adiation energy, the system being self-activating, turning itself automatically on and off, as a function of radiation intensity across the detector. In essence, when no radiation ...
10/19/1976
3943386Burner fuel supply control signal generating device
The device comprises flame detection means and a generating circuit adapted to deliver a signal when a flame signal, generated by the flame detection means, is applied to one of its inputs. The generating circuit is arranged so as to be unable to deliver ...
03/09/1976
 
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