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US2700380A
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Radiant tube heater and combustion air preheater therefor
Assignee: Surface Combustion Corp
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Filing: 1950-12-29
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Granted: 1955-01-25
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Expires: 1970-12-29
Abstract
No abstract record available.
Inventors
- 👤 Philip L Knight
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:57
CPC Classifications
F; F23; F23L; F23L15/00; F23L15/04; Y; Y02; Y02E; Y02E20/00; Y02E20/34
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1244864A
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US1288516A
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US2146410A
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US2188133A
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US2226816A
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US2200731A
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US2299901A
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US2391447A
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US2465711A
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US2549093A
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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) | 1958-01-24 | 1958-07-26 | 1959-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-01-24 | 1962-07-26 | 1963-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-01-24 | 1966-07-26 | 1967-01-25 | $7700.00 | Window Closed / Lapsed |