US2800282A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual burner forced air furnace and control system therefor
Assignee: WILLIAMSON Co
•
Filing: 1953-09-04
•
Granted: 1957-07-23
•
Expires: 1973-09-04
Abstract
No abstract record available.
Inventors
- 👤 William H Calahan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:34
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/275; G05D23/27535; G05D23/2754; F; F24; F24D; F24D19/00; F24D19/10; F24D19/1084; F24H; F24H9/00; F24H9/20; F24H9/2064; F24H9/2085
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2502345A
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US2516062A
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US2549952A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-07-22 | 1961-01-21 | 1961-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-22 | 1965-01-21 | 1965-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-22 | 1969-01-21 | 1969-07-23 | $7700.00 | Window Closed / Lapsed |