Patent US4163903A successfully refreshed from Google Patents.
US4163903A
Expired / Lapsed
US
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Flame monitoring apparatus
Assignee: Leeds and Northrup Co
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Filing: 1977-10-27
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Granted: 1979-08-07
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Expires: 1997-10-27
Abstract
Abstract The apparatus includes a radiation gathering device having a narrow acceptance angle and mounted in a multiburner boiler to sight substantially across the discharge end of the burner nozzle. Radiation collected by the gathering device is transmitted by a fiber optic path to a radiation detecting device. The manner in which the apparatus is constructed and mounted insures that the radiation detecting device will be responsive only to the radiation resulting from the associated burner and not influenced by radiation from other burners in the boiler installation, or radiation from the boiler itself.
Inventors
- 👤 Donald Robertson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:03
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/08; F23N5/082; F23N2229/00; F23N2229/18; F23N2237/00; F23N2237/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
139 words
Flame monitoring apparatus capable of signalling the loss of flame from a single burner of a multiple burner installation in which each burner is individually mounted in a recess in a boiler wall comprising: radiation collecting means mounted for collecting radiation from a limited optical path extending across the opening of said recess and terminating on a wall of said recess to collect radiation from the flame of an individual burner in said path when said flame is present and for collecting radiation from only a portion of the wall of said recess associated with said burner when said flame is out, and means connected to said radiation collecting means for producing an output signal indicative of the presence or absence of flame at said burner in response to the level of radiation collected by said radiation collecting means.
Claim 2
Dependent Claim
139 words
Flame monitoring apparatus capable of signalling the loss of flame from a single burner of a multiple burner installation in which each burner is individually mounted in a recess in a boiler wall comprising: radiation collecting means mounted for collecting radiation from a limited optical path extending across the opening of said recess and terminating on a wall of said recess to collect radiation from the flame of an individual burner in said path when said flame is present and for collecting radiation from only a portion of the wall of said recess associated with said burner when said flame is out, and means connected to said radiation collecting means for producing an output signal indicative of the presence or absence of flame at said burner in response to the level of radiation collected by said radiation collecting means.
Claim 3
Dependent Claim
26 words
Apparatus according to claim 1 in which said radiation collecting means includes a light pipe for conducting radiation from said flame to said radiation sensing means.
Claim 4
Dependent Claim
23 words
Apparatus according to claim 1 in which said radiation collecting means includes means for limiting the acceptance angle for said radiation collecting means.
Claim 5
Dependent Claim
15 words
Apparatus according to claim 2 in which said light pipe includes a fiber optic element.
Claim 6
Dependent Claim
17 words
Apparatus according to claim 3 in which said means for limiting the acceptance angle includes a diaphragm.
References Cited (Backward Citations)
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US3689773A
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US3936648A
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US3940753A
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US3988104A
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US4039844A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-08-06 | 1983-02-05 | 1983-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-08-06 | 1987-02-05 | 1987-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-08-06 | 1991-02-05 | 1991-08-07 | $7700.00 | Window Closed / Lapsed |