US3861854A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flame monitoring system
Assignee: BLOOM-1 Inc A CORP OF
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Filing: 1972-01-26
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Granted: 1975-01-21
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Expires: 1992-01-26
Abstract
Abstract Disclosed is a flame monitoring system having a sensing capacitor connected between the ''''hot'''' line of an a.c. power supply and a flame electrode in the flame and current isolated from the neutral line. Current rectified by flame charges the capacitor providing a flame indicating signal that is coupled into a control circuit fed by the a.c. power supply.
Inventors
- 👤 Lyman H Walbridge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:05
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/24; F23N5/242; F23N5/02; F23N5/12; F23N5/123; F23N5/20; F23N5/203; F23N2223/00; F23N2223/06; F23N2227/00; F23N2227/32; F23N2227/36; F23N2229/00; F23N2229/12
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
170 words
Circuit apparatus for monitoring flame generated by a fuel burner and comprising: first and second input terminals for connection to a source of a.c. power; a flame sensing electrode for disposition adjacent a fuel burner in the region occupied by flame emanating therefrom; direct current sensing means connected between said first terminal and said flame sensing electrode; said direct current sensing means being electrical current isolated from said second input terminal and adapted to produce a flame signal in response to current flow supported by a flame emanating from the burner; ground circuit means electrically isolated from said first and second terminals, said ground circuit means adapted for connecting a ground wire of a three-wire supply with a second electrode means spaced from said first electrode in said region occupied by flame; and control means connected between said first and second terminals so as to be powered by the source of a.c. power connected thereto, and coupled to said sensing means so as to be responsive to said flame signal.
Claim 2
Dependent Claim
170 words
Circuit apparatus for monitoring flame generated by a fuel burner and comprising: first and second input terminals for connection to a source of a.c. power; a flame sensing electrode for disposition adjacent a fuel burner in the region occupied by flame emanating therefrom; direct current sensing means connected between said first terminal and said flame sensing electrode; said direct current sensing means being electrical current isolated from said second input terminal and adapted to produce a flame signal in response to current flow supported by a flame emanating from the burner; ground circuit means electrically isolated from said first and second terminals, said ground circuit means adapted for connecting a ground wire of a three-wire supply with a second electrode means spaced from said first electrode in said region occupied by flame; and control means connected between said first and second terminals so as to be powered by the source of a.c. power connected thereto, and coupled to said sensing means so as to be responsive to said flame signal.
Claim 3
Dependent Claim
25 words
Circuit apparatus according to claim 1 wherein said direct current sensing means comprises a capacitive element for storing the current flow supported by the flame.
Claim 4
Dependent Claim
44 words
Circuit apparatus according to claim 1 wherein said direct current sensing means comprises a signal voltage source means that provides a d.c. signal voltage with respect to an a.c. voltage applied to said first terminal in response to current flow supported by the flame.
Claim 5
Dependent Claim
41 words
Circuit apparatus according to claim 3 wherein said signal voltage source means comprises a discharge capacitor for storing energy in response to current flow through the flame and switching means for periodically discharging said discharge capacitor to produce said signal voltage.
Claim 6
Dependent Claim
43 words
Circuit apparatus according to claim 4 wherein said direct current sensing means comprises a storage capacitor for storing energy in response to current flow through the flame, said storage capacitor being coupled to said discharge capacitor so as to provide electrical energy thereto.
Claim 7
Dependent Claim
37 words
Circuit apparatus according to claim 5 wherein said control means comprises a load and an SCR for controlling energization thereof, said SCR being coupled to said sensing means so as to be gated by said signal voltage.
Claim 8
Dependent Claim
18 words
Circuit apparatus according to claim 6 wherein said load comprises a solenoid for controlling a fuel supply valve.
Claim 9
Dependent Claim
19 words
Circuit apparatus according to claim 1 wherein said control means comprises an electrical operator for a fuel supply valve.
Claim 10
Dependent Claim
36 words
Circuit apparatus according to claim 1 wherein said control means comprises spark electrode means for supporting ignition sparks in said region, and a transformer having a winding for providing ignition pulses to said spark electrode means.
Claim 11
Dependent Claim
16 words
Circuit apparatus according to claim 9 wherein said spark electrode means comprises said flame sensing electrode.
Claim 12
Dependent Claim
25 words
Circuit apparatus according to claim 10 wherein said second electrode comprises the burner providing the flame, and said ground circuit comprises an electrically conductive housing.
Claim 13
Dependent Claim
61 words
Circuit apparatus according to claim 2 wherein said direct current sensing means comprises energy storage means for storing energy in said direct current; and including sampling means for periodically sampling the energy level stored in said energy storage means, and timing means coupled to said sampling means and adapted to produce sampling thereby at substantially zero-crossings of said a.c. power source.
Claim 14
Dependent Claim
30 words
Circuit apparatus according to claim 12 wherein said timing means produces said samplings only on particular zero-crossings during which said a.c. power source is proceeding to produce said direct current.
Claim 15
Dependent Claim
104 words
Circuit apparatus for monitoring flame generated by a fuel burner and comprising valve means for controlling flow of fuel to the burner; energy source means for providing a level of energy dependent upon the presence of flame at the burner; electrical sampling means for detecting the energy level provided by said source means, said sampling means drawing power only from said source means and providing a periodic output signal indicative of flame at the burner; and control means for closing said valve to prevent fuel flow to said burner in response to the absence of a minimum energy level sampled by said sampling means.
Claim 16
Dependent Claim
104 words
Circuit apparatus for monitoring flame generated by a fuel burner and comprising valve means for controlling flow of fuel to the burner; energy source means for providing a level of energy dependent upon the presence of flame at the burner; electrical sampling means for detecting the energy level provided by said source means, said sampling means drawing power only from said source means and providing a periodic output signal indicative of flame at the burner; and control means for closing said valve to prevent fuel flow to said burner in response to the absence of a minimum energy level sampled by said sampling means.
Claim 17
Dependent Claim
41 words
Circuit apparatus according to claim 14 wherein said energy source means comprises flame responsive means for providing a direct current in response to the presence of flame at the burner, and energy storage means for storing energy in said direct current.
Claim 18
Dependent Claim
22 words
Circuit apparatus according to claim 15 wherein said control means comprises amplifier means for amplifying the energy sampled by said sampling means.
Claim 19
Dependent Claim
34 words
Circuit apparatus according to claim 16 wherein said energy storage means comprises a discharge capacitance charged in response to flow of said direct current and discharged into said amplifier means by said sampling means.
Claim 20
Dependent Claim
54 words
Circuit apparatus according to claim 17 wherein said energy storage means further comprises a storage capacitance charged by said direct current so as to store energy therein and coupled to said discharge capacitor so as to provide charging current thereto and including current limiting means connected between said storage capacitance and said discharge capacitance.
Claim 21
Dependent Claim
24 words
Circuit apparatus according to claim 18 wherein said sampling means comprises a timer electronic switch for discharging said storage capacitance into said amplifier means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |