US2107871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil burning furnace
Assignee: Chicago Flexible Shaft Co
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Filing: 1934-10-01
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Granted: 1938-02-08
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Expires: 1954-10-01
Abstract
No abstract record available.
Inventors
- 👤 John W Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:51
CPC Classifications
F; F23; F23C; F23C99/00; F23D; F23D11/00; F23D11/36; F23D11/44; F23C2700/00; F23C2700/02; F23C2700/026
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) | 1941-02-07 | 1941-08-09 | 1942-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-02-07 | 1945-08-09 | 1946-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-02-07 | 1949-08-09 | 1950-02-08 | $7700.00 | Window Closed / Lapsed |