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US2199183A
Expired / Lapsed
US
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Hot air furnace and controls therefor
Assignee: Individual
•
Filing: 1938-11-16
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Granted: 1940-04-30
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Expires: 1958-11-16
Abstract
No abstract record available.
Inventors
- 👤 George H Lippincott
- 👤 Edward H Ruppert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:01
CPC Classifications
F; F24; F24H; F24H9/00; F24H9/20; F24H9/2064; F24H9/2085; F24H15/00; F24H15/20; F24H15/254; F24H15/30; F24H15/33; F24H15/335; F24H15/345; F24H15/355; F24H15/36
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) | 1943-04-30 | 1943-10-30 | 1944-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-04-30 | 1947-10-30 | 1948-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-04-30 | 1951-10-30 | 1952-04-30 | $7700.00 | Window Closed / Lapsed |