US2737643A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flame detection apparatus
Assignee: Phillips Petroleum Co
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Filing: 1952-10-02
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Granted: 1956-03-06
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Expires: 1972-10-02
Abstract
No abstract record available.
Inventors
- 👤 Jr Ross S Marsden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:46
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/12; F23N5/123; F23N2229/00; F23N2229/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
FLAME DETECTING APPARATUS COMPRISING IN COMBINATION, AN ELECTRICAL CIRCUIT ADAPTED TO FUNCTION AS A RECTIFIER WHEN BRIDGED BY A FLAME, A SOURCE OF ALTERNATING ELECTRICAL ENERGY OF FIRST FREQUENCY APPLIED ACROSS SAID CIRCUIT, SAID CURRENT INDICATING MEANS CONNECTED ACROSS SAID CIRCUIT, SAID CURRENT INDICATING MEANS INCLUDING A FILTER TUNED TO PASS SIGNALS OF FREQUENCY TWICE THE FREQUENCY OF SAID SOURCE OF ALTERNATING ELECTRICAL ENERGY
Claim 2
Dependent Claim
64 words
FLAME DETECTING APPARATUS COMPRISING IN COMBINATION, AN ELECTRICAL CIRCUIT ADAPTED TO FUNCTION AS A RECTIFIER WHEN BRIDGED BY A FLAME, A SOURCE OF ALTERNATING ELECTRICAL ENERGY OF FIRST FREQUENCY APPLIED ACROSS SAID CIRCUIT, SAID CURRENT INDICATING MEANS CONNECTED ACROSS SAID CIRCUIT, SAID CURRENT INDICATING MEANS INCLUDING A FILTER TUNED TO PASS SIGNALS OF FREQUENCY TWICE THE FREQUENCY OF SAID SOURCE OF ALTERNATING ELECTRICAL ENERGY
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) | 1959-03-06 | 1959-09-05 | 1960-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-03-06 | 1963-09-05 | 1964-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-03-06 | 1967-09-05 | 1968-03-06 | $7700.00 | Window Closed / Lapsed |