US3705783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Burner safeguard control apparatus
Assignee: Honeywell Inc
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Filing: 1971-07-21
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Granted: 1972-12-12
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Expires: 1991-07-21
Abstract
Abstract A fuel burner control system which includes a flame detecting unit and an electrically heated safety switch for safety starting and operating a fuel burner. The system includes a control relay connected in a unique and novel way to lock out and not recycle the system in the event of a loss of flame signal after the system has properly been started. The system does, however, recycle in the event of a power failure by using a fast dropout third relay.
Inventors
- 👤 James S Warren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:17
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/12; F23N5/123; F23N5/20; F23N5/203; F23N5/24; F23N5/242; F23N2227/00; F23N2227/12; F23N2227/22; F23N2227/28; F23N2229/00; F23N2231/00; F23N2231/04; F23N2231/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
402 words
Nonrecycle burner control apparatus for use with a fuel burner having spark ignition means, a pilot valve, and having an electrically energizable valve to control the flow of fuel to a main burner, the control apparatus being adapted to shut down and not recycle in the event of a flame failure, the control apparatus comprising: a control relay having a winding and normally open switch means; a flame detector circuit the input terminals of which are connected to means adapted to be subjected to the presence or absence of flame at the fuel burner, and the output terminals of which are connected to the winding of a flame relay having normally closed switch means and normally open switch means, said circuit being constructed and arranged to energize the winding of said flame relay in the presence of flame at the fuel burner and deenergize upon the absence of flame at the fuel burner; a further relay including a winding, normally closed switch means and normally open switch means, said normally closed switch means being connected to supply operating voltage to said spark ignition means, said normally open switch means being connected to supply operating voltage to said electrically energizable valve when said further relay is energized; circuit means under control of means responsive to the need for operation of the fuel burner including a normally closed switch means of said further relay and arranged to supply operating voltage to said control relay winding upon such a need to cause said control relay to pull in; holding circuit means for the winding of said control relay including normally open switch means of said control relay and normally open switch means of said flame relay; so that said control relay drops out on the occurrence of a flame failure; second circuit means energized responsive to the energization of said flame relay and including normally open switch means of said flame relay for supplying operating voltage to the winding of said further relay; and holding circuit means for the winding of said further relay including normally open switch means of said further relay, said holding circuit means arranged and connected so as not to be interrupted by any switch means of said control relay and flame relay whereby when said further relay has been energized in response to the energization of said flame relay said further relay will not drop out on a flame failure.
Claim 2
Dependent Claim
402 words
Nonrecycle burner control apparatus for use with a fuel burner having spark ignition means, a pilot valve, and having an electrically energizable valve to control the flow of fuel to a main burner, the control apparatus being adapted to shut down and not recycle in the event of a flame failure, the control apparatus comprising: a control relay having a winding and normally open switch means; a flame detector circuit the input terminals of which are connected to means adapted to be subjected to the presence or absence of flame at the fuel burner, and the output terminals of which are connected to the winding of a flame relay having normally closed switch means and normally open switch means, said circuit being constructed and arranged to energize the winding of said flame relay in the presence of flame at the fuel burner and deenergize upon the absence of flame at the fuel burner; a further relay including a winding, normally closed switch means and normally open switch means, said normally closed switch means being connected to supply operating voltage to said spark ignition means, said normally open switch means being connected to supply operating voltage to said electrically energizable valve when said further relay is energized; circuit means under control of means responsive to the need for operation of the fuel burner including a normally closed switch means of said further relay and arranged to supply operating voltage to said control relay winding upon such a need to cause said control relay to pull in; holding circuit means for the winding of said control relay including normally open switch means of said control relay and normally open switch means of said flame relay; so that said control relay drops out on the occurrence of a flame failure; second circuit means energized responsive to the energization of said flame relay and including normally open switch means of said flame relay for supplying operating voltage to the winding of said further relay; and holding circuit means for the winding of said further relay including normally open switch means of said further relay, said holding circuit means arranged and connected so as not to be interrupted by any switch means of said control relay and flame relay whereby when said further relay has been energized in response to the energization of said flame relay said further relay will not drop out on a flame failure.
Claim 3
Dependent Claim
20 words
The invention as described in claim 1 wherein the flame detector circuit input terminals are connected to a flame rod.
Claim 4
Dependent Claim
44 words
The invention as described in claim 1 in which the flame detector circuit has a first portion thereof which generates a cyclic signal when sensing flame and has a second portion thereof for energizing the flame relay only when said cyclic signal is present.
Claim 5
Dependent Claim
34 words
The invention as described in claim 1 wherein said second circuit means further includes normally open switch means of said control relay in series with said normally open switch means of said flame relay.
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) | 1975-12-12 | 1976-06-12 | 1976-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-12 | 1980-06-12 | 1980-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-12 | 1984-06-12 | 1984-12-12 | $7700.00 | Window Closed / Lapsed |