Patent US2889991A successfully refreshed from Google Patents.
US2889991A
Expired / Lapsed
US
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Heating system
Assignee: Individual
•
Filing: 1956-08-14
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Granted: 1959-06-09
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Expires: 1976-08-14
Abstract
No abstract record available.
Inventors
- 👤 Follansbee Rogers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:51
CPC Classifications
F; F24; F24D; F24D19/00; F24D19/10; F24D19/1096
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2165970A
Cited
US2241070A
Cited
US2483896A
Cited
US2503600A
Cited
US2549952A
Cited
US2784945A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-06-08 | 1962-12-08 | 1963-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-08 | 1966-12-08 | 1967-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-08 | 1970-12-08 | 1971-06-09 | $7700.00 | Window Closed / Lapsed |