Photoelectric Sensor Patents (Class 431/79)
  • Patent number: 4491142
    Abstract: An automatic fuel supply stopping device incorporated in fuel combustion equipment including a shut-off valve and a combustor. The automatic fuel supply stopping device comprises a fluid intercepting mechanism interposed in a channel through which the fuel supply to the combustor is supplied. A photosensor is adapted to detect fuel combustion in the combustor by radiation emitted from a thermosensitive luminous medium. The fluid intercepting mechanism alternately takes its first stable state or passage blocking state and is changed over, in response to an output from a sensor circuit, from the passage opening state to the passage blocking state.
    Type: Grant
    Filed: September 14, 1982
    Date of Patent: January 1, 1985
    Assignee: Touto Denki Kabushiki Kaisha
    Inventor: Kunio Shimizu
  • Patent number: 4477245
    Abstract: A flame monitor for a burner comprises an oscillator which generates a signal at a characteristic frequency, a flame modulator connected to the oscillator and the burner for modulating the flame which produces an electromagnetic signal at the same frequency and a signal detector for detecting the electromagnetic signal. A bandpass filter is connected to the detector for passing only the signal at the characteristic frequency. Circuitry is provided for detecting the intensity of the electromagnetic signal which is proportional to the flame temperature and which can be used to control the fuel or air supplied to the burner and thus optimize the flame. A single detector can be used to detect the flame from various burners where each burner is supplied with its own characteristic frequency and the detector is multiplexed to share its operation over the various burners.
    Type: Grant
    Filed: September 3, 1982
    Date of Patent: October 16, 1984
    Assignee: The Babcock & Wilcox Company
    Inventors: Joseph M. Giachino, Marion A. Keyes, IV
  • Patent number: 4455949
    Abstract: The burner is formed of a tubular housing including a central tubular passage and a boundary annular passage for feeding into the gasification reactor under high speed a carburation medium such as oxygen or steam. At least three intermediate channels of coaxial annular sections are symmetrically arranged about the central channel and each communicates with a separate inlet conduit for feeding a mixture of powderized fuel with a carrier gas. The transition between the annular intermediate channel and the tubular inlet conduits is made such that the varying outline of the cross-section encloses the same area as the tubular inlet conduit or the annular section intermediate channel. The central tubular channel and the boundary annular channel for feeding the carburation fluid is configurated so as to divert one stream of the carburation fluid at an angle of about 45.degree. toward the axially directed jet of the powderized fuel mixture.
    Type: Grant
    Filed: February 13, 1980
    Date of Patent: June 26, 1984
    Assignee: Brennstoffinstitut Freiberg
    Inventors: Horst Kretschmer, Klaus Fleischer, Peter Gohler, Manfred Schingnitz, Friedrich Berger, Aleksander Jegorow, Vasilij Fedotov, Vladimir Gavrilin, Ernest Gudymov, Vladimir Semenov, Igol Achmatov, Nikolaj Majdurov, Evgenij Avraamov
  • Patent number: 4435149
    Abstract: A furnace burner flame monitoring method and apparatus are provided for controlling the burner fuel mixture in order to operate a furnace at maximum burning efficiency. A radiometer having an infrared detector views the flame and detects infrared radiation emitted from the flame. A filter wheel is interposed between the infrared detector and the flame for transmitting at least three different, discrete, infrared radiation bands from the flame to the detector with the detector thereby generating at least three signals in response to radiation received from the three infrared radiation bands. A control parameter is derived using a ratio of at least two of the signals from the infrared radiation bands which are compensated for flame length using a third of the signals generated by the infrared detector. The control parameter may then be utilized for controlling the fuel/air mixture which is burned for thus monitoring and maintaining the furnace at maximum efficiency.
    Type: Grant
    Filed: December 7, 1981
    Date of Patent: March 6, 1984
    Assignee: Barnes Engineering Company
    Inventor: Robert W. Astheimer
  • Patent number: 4415264
    Abstract: This invention relates to a spectrophotometer which includes a burner adapted for burning a gaseous fuel and for atomizing a sample to be analyzed in a burner compartment, mechanical elements or electrical circuitry serving to periodically pass a beam of light through the burner compartment, a detector, electrical circuitry for energizing the detector during the period of absence of the beam of light through the burner compartment, said detector being adapted when energized to produce an electronic signal representative of the presence of a flame in the burner compartment; and control elements responsive to the electronic signal for controlling the feeding of fuel to the burner.
    Type: Grant
    Filed: June 25, 1981
    Date of Patent: November 15, 1983
    Assignee: The Perkin-Elmer Corporation
    Inventor: Charles M. Wittmer
  • Patent number: 4406612
    Abstract: An oil burner primary control in an interrupted ignition burner control system includes a regulating circuit for regulating the voltage across a flame-responsive photo-conductive cell. The regulating circuit ensures that, in the event the cell becomes defective so as to exhibit abnormal resistance characteristics, the system will not permit fuel to flow unless a burner flame exists or unless the igniter and a safety circuit are energized.
    Type: Grant
    Filed: October 22, 1981
    Date of Patent: September 27, 1983
    Assignee: Emerson Electric Co.
    Inventor: Donald E. Donnelly
  • Patent number: 4402664
    Abstract: An improved waste oil heater that includes a vaporizer pan having a mounting ring, a replaceable aluminum foil piece mounted on the ring to form the bottom of the pan and a member mounted on the ring to provide threads, a tool threadingly engageable with the threaded ring member for breaking the pan loose from the bottom wall of a burner pot and removing the ring with caked residue thereon for purposes of cleaning, the burner pot having a novel arrangement of apertures for flow of air into the pot, and solid state electronic control apparatus to control the feed of waste oil that automatically compensates for variations in viscosities and caloric values found in a variety of used oils and automatically discontinues the feed in the event the flame in the burner pot goes out.
    Type: Grant
    Filed: May 5, 1981
    Date of Patent: September 6, 1983
    Inventor: Wolfgang A. Kutrieb
  • Patent number: 4395224
    Abstract: A burner control apparatus for use with a fuel installation that has an operating control to produce a request for burner operation, a flame sensor to produce a signal when flame is present in the monitored combustion chamber, and one or more devices for control of ignition and/or fuel flow. The burner control apparatus comprises lockout apparatus for de-energizing the control apparatus, a control device for actuating the ignition and/or fuel control devices, and a timing circuit that provides four successive and partially overlapping timing intervals of precise relation, including a purge timing interval, a pilot ignition interval, and a main fuel ignition interval. The present invention further includes a burner control system which verifies the proper operation of certain sensors in a burner or furnace including particularly the air flow sensor.
    Type: Grant
    Filed: September 24, 1980
    Date of Patent: July 26, 1983
    Assignee: Electronics Corporation of America
    Inventor: Phillip J. Cade
  • Patent number: 4395229
    Abstract: An ignitor assembly for oil stoves is disclosed which includes an ignitor plug held in alignment with an exposed portion of a wick for firing the wick through the utilization of discharge originated from the ignitor plug. A light-sensitive element is disposed at a predetermined distance from the ignitor plug and in alignment with the exposed portion of the wick.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: July 26, 1983
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shuji Yasuhira, Shinichi Naka
  • Patent number: 4370125
    Abstract: A control system for fluid fuel burners, particularly for blue-flame oil burners, utilizes flame conduction to control energizing of the light emitting portion of an optical coupler. Circuit means including the light responsive portion of the optical coupler is effective, in the presence of a predetermined level of illumination from the light emitting portion which occurs in the absence of a burner flame, to enable flow of a combustible fuel-air mixture and energizing of ignition means, and, in the subsequent absence of the predetermined level of illumination when burner flame exists, to terminate energizing of the ignition means and to enable continued flow of the combustible mixture. The control system further includes means for reducing the rate and level of illumination of the light emitting portion so that it requires a predetermined time period for the light emitting portion to be energized to the predetermined level of illumination.
    Type: Grant
    Filed: October 1, 1980
    Date of Patent: January 25, 1983
    Assignee: Emerson Electric Co.
    Inventors: Donald E. Donnelly, Francis J. Maney
  • Patent number: 4370557
    Abstract: In a multi-burner boiler or industrial furnace installation that uses pulverized coal for fuel and utilizes an oil pilot torch it has been difficult to sense and discriminate satisfactorily between safe and unsafe burner operation in these multi-burner arrangements. By using both a Si detector (visible light responsive) and a lead sulfide detector (infrared responsive) and selectively combining the signals therefrom, the best characteristics of both detectors are utilized to provide satisfactory flame sensing.
    Type: Grant
    Filed: August 27, 1980
    Date of Patent: January 25, 1983
    Assignee: Honeywell Inc.
    Inventors: Roger E. Axmark, Ernest A. Satren
  • Patent number: 4368031
    Abstract: A flame monitoring system for use on the furnace (10) of a vapor generator (2) employing tiltable burners (14) and particularly on a furnace equipped with tilting burners arranged in accord with the tangential firing method. Each burner is provided with its own individual scanner. Each scanner (20) is disposed to sight transversely across the base (30) of the flame (18) emanating from its associated burner (14). A plurality of at least three light transmission tubes (26) are stationarily mounted within each scanner head (24) with at least one tube (26A) mounted to sight at an upward acute angle across the flame, at least one other tube (26B) mounted to sight horizontally across the flame, and at least a third tube (26C) mounted to sight at a downward acute angle across the flame. A separate fire ball scanner (60) is mounted in the waterwall and aimed to sight at the center of the furnace (10) to monitor the fire ball (50) formed therein by the flames (18) emanating from the individual burners (14).
    Type: Grant
    Filed: July 14, 1980
    Date of Patent: January 11, 1983
    Assignee: Combustion Engineering, Inc.
    Inventor: Roman Chadshay
  • Patent number: 4351316
    Abstract: Combustion apparatus for burning waste oils of various viscosities with high combustion efficiency and which can meet strict polution regulations comprises primary and secondary combustion chambers with the secondary combustion chamber located above the primary combustion chamber and the primary combustion chamber located within an outer housing so as to define between the outer housing and the primary combustion chamber a plenum space. An air blower delivers air to the plenum space which feeds air into the primary combustion chamber through air inlet openings in its side wall. The primary combustion chamber has a burner bowl provided at its base and a burner ring disposed above the burner bowl. Oil is supplied at a constant rate to the burner bowl via a positive displacement pump. The burner ring features a central aperture and two concentrically disposed rings of orifices with the orifices of the outer ring being of larger diameter than the orifices of the inner ring.
    Type: Grant
    Filed: October 9, 1979
    Date of Patent: September 28, 1982
    Inventor: Walter Kroll
  • Patent number: 4321480
    Abstract: A solid state switching circuit using a capacitive feedback that creates a positive differential. This positive differential overcomes any half-wave operation of the solid state switches caused by lack of symmetry in its gating circuit.
    Type: Grant
    Filed: February 14, 1980
    Date of Patent: March 23, 1982
    Assignee: Honeywell Inc.
    Inventor: Gregory M. Miles
  • Patent number: 4278419
    Abstract: A primary oil burner safety control and intermittent ignition system for initiating and supervising the combustion of fuel oil in furnaces, the system including thermostatic switch means controlling the energization of a relay having contacts controlling the energization of an oil burner, means constantly monitoring the state of the relay contacts with respect to the state of the thermostatic switch means, and means to effect safety shutdown of the oil burner in the event the state of the relay contacts disagrees with the state of the thermostatic switch means.
    Type: Grant
    Filed: April 30, 1979
    Date of Patent: July 14, 1981
    Assignee: Robertshaw Controls Company
    Inventors: Jon H. Bechtel, Frederick J. Geary
  • Patent number: 4242081
    Abstract: An oil burner primary control in an interrupted ignition burner control system includes a miniature coupling transformer for controlling operation of the igniter. The gate circuit of a flame responsive switch is effective, in the absence of a burner flame, to generate a plurality of gating pulses at a frequency substantially greater than line frequency. The flame responsive switch is cyclically gated on by the pulses for energizing a safety switch resistance heater. The primary winding of the coupling transformer is connected in the gate circuit of the flame responsive switch and is responsive to the gating pulses to induce voltage pulses in its secondary winding which is connected in the gate circuit of an ignition switch controlling the igniter. At least one of the pulses occurs sufficiently early in each half cycle of the sine wave alternating current appearing at the ignition switch so that the ignition switch conducts during essentially all of the sine wave, as long as there is no burner flame.
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: December 30, 1980
    Assignee: Emerson Electric Co.
    Inventors: Donald E. Donnelly, William B. Feero
  • Patent number: 4233596
    Abstract: A flare monitoring apparatus for detecting the generation of black smoke in a flare, the excessiveness of a flare and extinguishment of a flare based on the ratio and/or difference between an emissive power of infrared radiation emitted from a flare at a wave length at which a peak of the emissive power due to a resonance infrared radiation of a specified gas contained in a flue gas exists and an emissive power of infrared radiation emitted from the flare at another wave length at which a peak of the emissive power due to a resonance radiation does not exist. The apparatus produces an alarm and automatically controls the state of the flare upon the detection of the abnormality of the flare.
    Type: Grant
    Filed: August 15, 1978
    Date of Patent: November 11, 1980
    Assignee: Showa Yuka Kabushiki Kaisha
    Inventors: Hiroo Okamoto, Shunsaku Nakauchi
  • Patent number: 4167389
    Abstract: An oil burner primary control in an interrupted ignition system includes therein circuit means responsive to burner flame for initiating energizing of an ignition transformer in the absence of burner flame and for maintaining energizing thereof for a short time period beyond the time at which the burner flame appears.
    Type: Grant
    Filed: November 2, 1977
    Date of Patent: September 11, 1979
    Assignee: Emerson Electric Co.
    Inventors: Donald E. Donnelly, John W. Breig, Robert L. Gellner
  • Patent number: 4150941
    Abstract: A device for photoelectrically starting and stopping the operation of a bunsen burner in response to the shadow of an operator's hand holding an object to be heated includes a solenoid valve in a line supplying gas to the burner and electronic control circuitry having secondary and primary photoelectric cells arranged in a differential response circuit. Changes in the intensity of the ambient light are cancelled by the differential response circuit, while a hand shadow, which affects only the primary cell, triggers the solenoid valve, via a gate circuit and solenoid switch.
    Type: Grant
    Filed: September 28, 1977
    Date of Patent: April 24, 1979
    Assignee: Firma Dr. Th. Wieland
    Inventor: Friedrich Obermeier
  • Patent number: 4113419
    Abstract: Burner control apparatus includes a control device for actuating an ignition control means, and a timing circuit for providing an ignition timing interval of precise duration. The timing circuit is actuated in response to a request for burner operation and the control device is energized in response to the actuated timing circuit. The control device is maintained energized if a signal from the flame sensor is received before the end of the ignition timing interval, and the control device is deenergized and lockout circuitry is energized in the absence of a signal from the flame sensor.
    Type: Grant
    Filed: April 12, 1976
    Date of Patent: September 12, 1978
    Assignee: Electronics Corporation of America
    Inventor: Phillip J. Cade
  • Patent number: 4070144
    Abstract: A control system for a fuel flow control valve which is enabled on thermostatic demand and closed thereafter if ignition fails. The control system includes an enabling circuit for the control valve in series with a controlled switching device and a circuit for energizing a fuel igniting system. The control system also includes circuitry for selectively supplying enabling pulses to the controlled switching device to enable the control valve and to energize the fuel igniting system along with timing circuitry for selectively preventing the application of those enabling pulses to the controlled switching device. The timing circuitry includes a transistor which when enabled shunts those pulses to ground rather than to the controlled switching device, and the control system is fail safe in the sense that neither a shorted transistor nor a shorted controlled switching device will allow the escape of significant unburned fuel.
    Type: Grant
    Filed: January 30, 1976
    Date of Patent: January 24, 1978
    Assignee: General Electric Company
    Inventors: Alvin D. Wyland, Jaykishan C. Patel
  • Patent number: 4059385
    Abstract: A real time monitoring and control system for single or multi-fired combustion systems which permits adjustment of the air fuel ratio in the system for optimized efficiency and minimized pollution content in the exhaust gas, while providing safety control of the combustion process. The system includes a high sensitivity light sensor which is utilized to monitor the combustion flame and provide an electrical output proportional to flame temperature, that is utilized to control the air fuel ratio of the system. The wavelength sensitivity of the sensor is capable of selection, for example by selection of sensor type and/or use of appropriate filters, to monitor a predetermined range or region of the flame emission spectrum in order to enable correlation of the intensity of the emission spectrum of the type of fuel being utilized, i.e., oil or natural gas, with temperature and combustion efficiency.
    Type: Grant
    Filed: July 26, 1976
    Date of Patent: November 22, 1977
    Assignee: International Business Machines Corporation
    Inventors: Louis Gulitz, Theodore William Kwap, Walter Irving Lisle, Daniel Francis O'Kane, Michael Robert Poponiak
  • Patent number: 4043743
    Abstract: A combustion control system is operated based on the detection of smoke density. A photoelectric device measures the intensity of light directed through the smoke by a lamp in order to measure the smoke density. This measurement is employed to control fuel and/or air supply or the like. To provide a standard reference, light is directed from the lamp through an alternate path not affected by the smoke to the photoelectric device. A shutter mechanism alternately exposes the photoelectric device to light passing through or circumventing the smoke. The photoelectric measurement is compared with a standard and the comparison is used to adjust circuitry connected to the photoelectric device to stabilize the effects of the latter. A continuous monitoring of the adjustment is carried out to determine when an acceptable range of adjustment has been exceeded. A smoke density amplifier is employed to increase effectiveness.
    Type: Grant
    Filed: August 9, 1976
    Date of Patent: August 23, 1977
    Assignee: B.S.C. Industries Corporation
    Inventor: Seymour Seider
  • Patent number: 4043742
    Abstract: A furnace containing a burner, supplied by fuel to be ignited at the burner, in the presence of air, is provided with a viewing duct for viewing the flame and means for detecting the radiation intensity at a plurality of different wavelengths of the radiation spectrum. The output from the detector is amplified and integrated and a signal representing the ratio of intensities at the selected wavelengths is applied to an indicator to indicate fuel-air ratio and also is applied to control means for the fuel flow or the air flow, or both, to control the fuel-air ratio at the burner and to maintain it substantially constant at a desired value. This can be done at more than one burner, providing balanced furnace operation. With this balanced furnace, there is improved firing efficiency, resulting in fuel saving and lowered pollution emissions. A computer type master controller can be used to correlate the fuel-air ratios for the individual burners.
    Type: Grant
    Filed: May 17, 1976
    Date of Patent: August 23, 1977
    Assignee: Environmental Data Corporation
    Inventors: Dale W. Egan, Lyman F. Gilbert, Harry C. Lord, Alan E. Opel, Geoffrey B. Holstrom
  • Patent number: 4028047
    Abstract: A device for electrically starting and stopping the operation of a gas burner in response to the shadow of the user's hand holding an object to be heated, the device including a solenoid valve in the gas line and a dimmer circuit with a directional photoelectric sensor, a switching amplifier, and a valve relay controlling the solenoid valve. The dimmer circuit can be bypassed for continuous operation by means of a selector switch.
    Type: Grant
    Filed: December 19, 1975
    Date of Patent: June 7, 1977
    Assignee: Firma Dr. Th. Wieland
    Inventors: Alfred Strunz, Jurgen Rohrer
  • Patent number: 4024412
    Abstract: A primary side of a burner control circuit includes a triac switch for applying a line voltage to a burner motor and an igniter in response to a signal from a first optical coupler, and a circuit breaker responsive to a second optical coupler for disconnecting the primary from the line voltage. A low voltage or secondary side of the control circuit, which is responsive to a thermostat, contains a light sensitive element for detecting a flame at the burner and the light sources for both optical couplers and, as such, is effective to control both the triac and the circuit breaker. The secondary also contains an electrical timing circuit for causing the triac to shut the motor and igniter off when, a predetermined time after a call for heat by the thermostat has elapsed, a flame has not been detected in the furnace.
    Type: Grant
    Filed: February 7, 1975
    Date of Patent: May 17, 1977
    Assignee: The Scott & Fetzer Company (France Division)
    Inventor: Robert Bruce MacAskill, Jr.
  • Patent number: 4015927
    Abstract: A method of operating a burner in which fuel and airborne combustible debris to be incinerated are received in a burner while fuel delivered to the burner is decreased in quantity in the absence of debris to be incinerated so that delivery of excess fuel in the absence of debris is avoided.
    Type: Grant
    Filed: January 12, 1976
    Date of Patent: April 5, 1977
    Assignee: Aero-Dyne Manufacturing, Inc.
    Inventor: Clifford Culpepper, Jr.
  • Patent number: 3990835
    Abstract: A technique is described for igniting the oil shale rubble pile in an in situ oil shale retort. A gas-air burner is lowered through a hole to a plenum over the oil shale to be ignited. An excess of air is passed through the hole and around the burner so that it is kept cool as the flame from it impinges on the rubble pile and the air also provides oxygen for combustion of carbonaceous material in the shale. Preferably the burner is in a cylindrical housing having a refractory exit nozzle at its lower end so that a hot flame is ejected downwardly. Air is brought to the inlet of the nozzle through an outer feed tube in the housing and coaxial therewith. Combustible gas is introduced through an inner axial feed tube which terminates short of the inlet end of the nozzle in a mixing chamber. A mixing orifice is provided between the mixing chamber and the nozzle for thorough mixing of the gas and inhibition of travel of the flame back into the burner.
    Type: Grant
    Filed: July 26, 1974
    Date of Patent: November 9, 1976
    Assignee: Occidental Petroleum Corporation
    Inventor: Robert S. Burton, III
  • Patent number: 3988104
    Abstract: The invention is concerned with a burner monitor comprising a variator which is arranged to cause a predetermined fluctuation of the flow of a reactant to a burner to cause flickering of the burner flame. A detector for radiation from the flame from the burner emits a signal corresponding to the radiation. A comparator assesses the polarity of any correlation between the applied fluctuations and the signal from the detector and an indicator indicates the assessed polarity. The output from the indicator may be integrated to produce a quantitative assessment of the fuel rich or fuel lean flame condition.
    Type: Grant
    Filed: May 7, 1975
    Date of Patent: October 26, 1976
    Assignee: Land Pyrometers Limited
    Inventor: Roy Barber
  • Patent number: 3986814
    Abstract: A device for controlling a gaseous or liquid fuel fired appliance as a function of a parameter includes a fuel supply controlled by a valve operated in dependence on a signal furnished by means sensitive to the parameter. The device includes a first circuit triggerable by the parameter-sensitive means when the parameter exceeds a first value and a second circuit triggerable by the parameter-sensitive means when the parameter falls below a second value lower than the first value. These circuits operate the valve appropriately for a given period of time. The device includes a spark generator for ignition of the fuel and an inhibitor to stop spark generation on fuel ignition. The device also includes first and second dc sources for independent supply of the first and second circuits, which require negligible current when not operative.
    Type: Grant
    Filed: October 1, 1975
    Date of Patent: October 19, 1976
    Assignee: Bicosa-Societe de Recherches
    Inventor: Henri Courier De Mere
  • Patent number: 3975137
    Abstract: A burner control circuit in which the flame of a high capacity burner is ignited by a spark or hot wire and ignition is sensed by a photocell positioned outside the flame and controlling a semiconductor current amplifier which controls the current in a series path through the solenoid of a fuel valve, a thermal time delay relay and a bridge rectifier energized by a transformer winding. The relay opens the series circuit a predetermined time after the transformer has been energized if ignition has not been achieved. The system using the burner is a high capacity heater having the burner positioned inside a plenum of an extended surface heat exchanger for heating a fluid to supply to a second heat exchanger, and energization of the control circuit for the ignition and flame sensing is controlled by the heat required by the first and/or second heat exchangers.
    Type: Grant
    Filed: February 3, 1975
    Date of Patent: August 17, 1976
    Assignee: Raytheon Company
    Inventor: William H. Hapgood
  • Patent number: 3964044
    Abstract: An alarm system uses a series string of sensors including burglar, fire and cold detectors in series with a relay coil. The coil when activated, assures that all sensors are indicating a no fault condition and a contact associated with the coil, energizes a source of light to illuminate a photo detector. Upon an intrusion, the coil is energized causing an alarm to activate, which alarm may cause another alarm to continue warning of a fault in spite of a predetermined reset condition, which may undesirably occur.Other embodiments show a technique of monitoring a plurality of secured locations to determine the exact one experiencing a fault.
    Type: Grant
    Filed: November 29, 1974
    Date of Patent: June 15, 1976
    Inventor: Anthony R. Busco
  • Patent number: 3959697
    Abstract: A solid state oil burner safety control system with integral ignition and particularly adapted for use with a motor powered oil burner, the system providing intermittent ignition, timed safety shutdown, motor starting capability and automatic restart in the event of combustion failure. The system is also adapted to prevent burner motor starting if the line voltage is below a predetermined value.
    Type: Grant
    Filed: November 29, 1974
    Date of Patent: May 25, 1976
    Assignee: Robertshaw Controls Company
    Inventors: Frederick T. Bauer, Frederick J. Geary
  • Patent number: 3947219
    Abstract: An interrupted ignition system for a burner control circuit having a primary side which has as its primary function the application of a line voltage to a burner motor and a fuel igniter and a secondary side, which is responsive to a thermostat, and includes a light sensitive element for detecting a flame at the burner plus a current responsive element which in combination with a circuit breaking switch in the primary functions as a circuit breaker for disconnecting the igniter and motor from the line voltage under certain conditions. The igniter is controlled by a triac switch in the primary side which in turn is responsive to an optical coupler connected to the secondary side of the burner control circuit. When the thermostat contacts are closed, thereby indicating a call for heat, the optical coupler will cause the triac to switch on resulting in current flow through the igniter.
    Type: Grant
    Filed: February 24, 1975
    Date of Patent: March 30, 1976
    Assignee: Sundstrand Corporation
    Inventor: Eugenio Espiritu Santo
  • Patent number: 3947218
    Abstract: An electronic network for safe operation of an infrared flame flicker burner control system is disclosed. The network is placed across the infrared flame detector and modifies the detector's action in the event of a flameout so that a refractory shimmer effect is reduced to avoid falsely causing the burner control system to indicate the presence of flame.
    Type: Grant
    Filed: January 23, 1975
    Date of Patent: March 30, 1976
    Assignee: Honeywell Inc.
    Inventor: William R. Landis
  • Patent number: 3938939
    Abstract: The primary side of the burner control circuit, which has as its primary function the application of a line voltage to the burner motor and igniter, includes: a triac switch for applying the line voltage to the burner motor and igniter; in response to a first optical coupler; a circuit breaker switch for disconnecting the primary from the line voltage; and a light source for a second optical coupler. The secondary side of the burner control circuit, which is responsive to a thermostat, includes: a light sensitive element for detecting a flame at the burner; a light source for the first optical coupler; and a current responsive element which in combination with the circuit breaking switch in the primary functions as a circuit breaker.
    Type: Grant
    Filed: February 12, 1975
    Date of Patent: February 17, 1976
    Assignee: Sundstrand Corporation
    Inventors: Robert Bruce MacAskill, Jr., Charles Norvin Porter
  • Patent number: 3938940
    Abstract: A solid state primary control and ignition system for oil burners, the system including burner control means, an isolated low voltage control circuit, plasma generator means, combustion initiation means and combustion sensing means, and being effective to provide improved intermittent ignition and improved control for initiating and supervising the combustion of fuel oil in furnaces.
    Type: Grant
    Filed: January 9, 1975
    Date of Patent: February 17, 1976
    Assignee: Robertshaw Controls Company
    Inventor: Frederick T. Bauer
  • Patent number: 3936648
    Abstract: A filter having a cut-off frequency of the order of 50Hz is included in the circuit of flame monitoring apparatus to remove signals below the cut-off frequency. In the circuit shown, a silicon p-n junction photo-electric pick-up is capacitively connected to an amplifier, the amplifier is connected to a high-pass filter, the output of the filter is connected to a further amplifier, the output of the further amplifier is applied to a detector integrator, the output of the detector integrator is connected to a Schmitt trigger, and the output of the trigger is applied to an output circuit giving a warning signal if the flame being monitored is extinguished. The use of sighting tubes for the photo-electric pick-ups is disclosed.
    Type: Grant
    Filed: March 18, 1974
    Date of Patent: February 3, 1976
    Assignee: Electricite de France
    Inventors: Pierre J. B. Cormault, Jean M. Megnoux
  • Patent number: 3932137
    Abstract: Burner apparatus in which fuel and airborne combustible debris to be incinerated are received in a burner while fuel delivered to the burner is decreased in quantity in the absence of debris to be incinerated so that delivery of excess fuel in the absence of debris is avoided.
    Type: Grant
    Filed: November 8, 1973
    Date of Patent: January 13, 1976
    Assignee: Aero-Dyne Manufacturing, Inc.
    Inventor: Clifford Culpepper, Jr.