← Back to Patent Explorer
US3975137A Expired / Lapsed US ⏱️ 0.0 years remaining

Burner control system

Assignee: Raytheon Co
•
Filing: 1975-02-03
•
Granted: 1976-08-17
•
Expires: 1995-02-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

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.

Inventors

  • 👤 William H. Hapgood

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 10:47
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/20; F23N1/00; F23N1/08; F23N1/082; F23N5/02; F23N5/08; F23N5/082; F23N2227/00; F23N2227/36; F23N2227/38; F23N2233/00; F23N2233/06; F23N2233/10

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 65 words
A heating system comprising: a burner positioned in a central plenum defined by an extended surface heat exchanger; optical sensing means for producing a control signal in response to the presence of a flame; and variable impedance means responsive to said sensing means for controlling the current through a series connected fuel control valve solenoid, thermal time delay means, and a source of electrical energy.
Claim 2
Dependent Claim 65 words
A heating system comprising: a burner positioned in a central plenum defined by an extended surface heat exchanger; optical sensing means for producing a control signal in response to the presence of a flame; and variable impedance means responsive to said sensing means for controlling the current through a series connected fuel control valve solenoid, thermal time delay means, and a source of electrical energy.
Claim 3
Dependent Claim 29 words
The heating system in accordance with claim 1 wherein said current controlling means comprises semiconductor means responsive to said optical sensing means and controlling the current through said solenoid.
Claim 4
Dependent Claim 15 words
The heating system in accordance with claim 2 wherein said semiconductor means comprises a transistor.
Claim 5
Dependent Claim 22 words
The heating system in accordance with claim 1 wherein said source of electrical energy comprises a transformer winding supplying a bridge rectifier.
Claim 6
Dependent Claim 98 words
A heating system comprising: a burner positioned in a central plenum defined by an extended surface heat exchanger; burner control means comprising optical sensing means responsive to the presence of a flame and controlling means for controlling the current through a series connected fuel control valve solenoid, thermal time delay means, and a source of electrical energy; and said burner being supplied with a fuel-air mixture from a blower whose input is supplied with said fuel from said valve through a pressure regulator which supplies gaseous fuel to the input of said blower at pressures below atmospheric pressure.
Claim 7
Dependent Claim 98 words
A heating system comprising: a burner positioned in a central plenum defined by an extended surface heat exchanger; burner control means comprising optical sensing means responsive to the presence of a flame and controlling means for controlling the current through a series connected fuel control valve solenoid, thermal time delay means, and a source of electrical energy; and said burner being supplied with a fuel-air mixture from a blower whose input is supplied with said fuel from said valve through a pressure regulator which supplies gaseous fuel to the input of said blower at pressures below atmospheric pressure.
Claim 8
Dependent Claim 117 words
In combination: a burner; a blower supplying said burner with a mixture of gaseous fuel and air; a solenoid controlled valve supplying the input of said blower with said gaseous fuel through a pressure regulator; and a control system for said burner comprising means for igniting said burner, sensing the presence of said ignition, and controlling the input of a semiconductor current amplifier in accordance with said sensing to vary the current through said amplifier and through said solenoid and a thermal time delay relay connected in series with said amplifier to open said series circuit a predetermined time after energization thereof when lack of a sensed signal indicates the absence of a flame at said burner.
Claim 9
Dependent Claim 117 words
In combination: a burner; a blower supplying said burner with a mixture of gaseous fuel and air; a solenoid controlled valve supplying the input of said blower with said gaseous fuel through a pressure regulator; and a control system for said burner comprising means for igniting said burner, sensing the presence of said ignition, and controlling the input of a semiconductor current amplifier in accordance with said sensing to vary the current through said amplifier and through said solenoid and a thermal time delay relay connected in series with said amplifier to open said series circuit a predetermined time after energization thereof when lack of a sensed signal indicates the absence of a flame at said burner.
Claim 10
Dependent Claim 31 words
The combination in accordance with claim 6 wherein said semiconductor amplifier comprises an emitter, a collector, and a base electrode being connected to an optical sensor for sensing said burner flame.
Claim 11
Dependent Claim 47 words
The combination in accordance with claim 7 wherein said base electrode is connected to said collector electrode through a control resistor and said base electrode is connected to said emitter electrode through said optical sensor whose resistance is reduced in the presence of radiation from said flame.
Claim 12
Dependent Claim 31 words
The combination in accordance with claim 8 wherein said series circuit is supplied with electrical energy from a source of power having a direct current component and an alternating current component.
Claim 13
Dependent Claim 19 words
The combination in accordance with claim 9 wherein said source of power comprises a transformer feeding a bridge rectifier.

References Cited (Backward Citations)

US2840146A Cited
US3537804A Cited
US3741709A Cited
US3770365A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-08-17 1980-02-16 1980-08-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-08-17 1984-02-16 1984-08-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-08-17 1988-02-16 1988-08-17 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag