Patent US3778218A successfully refreshed from Google Patents.
US3778218A
Expired / Lapsed
US
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Ignition and control systems for gas burners
Assignee: Emerson Electric Co
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Filing: 1971-02-01
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Granted: 1973-12-11
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Expires: 1991-02-01
Abstract
Abstract A BURNER IGNITION AND CONTROL CIRCUIT IN WHICH A NORMALLY OPEN THERMAL RELAY HAVING AN ELECTRICAL RESISTANCE HEATER SERIES CONNECTED ACROSS A POWER SOURCE WITH AN ELECTRICAL RESISTANCE GLOW IGNITER CLOSES TO EFFECT THE ENERGIZATION AND OPENING OF A NORMALLY CLOSED SOLENOID GAS VALE WHEN THE IGNITER AND RESISTANCE HEATER HAVE BEEN ENERGIZED FOR A PERIOD OF TIME SUFFICIENT TO INSURE THAT THE IGNITER HAS ATTAINED GAS IGNITION TEMPERATURE.
Inventors
- 👤 J Wright
- 👤 R Forrest
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:57
CPC Classifications
F; F23; F23Q; F23Q7/00; F23Q7/06; F23Q7/10; F23Q7/12; F23N; F23N5/00; F23N5/02; F23N5/04; F23N5/045; F23N2227/00; F23N2227/42
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |