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Patent US2568487A successfully refreshed from Google Patents.
US2568487A
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Multiple tube radiator forced circulation air heating furnace
Assignee: Individual
•
Filing: 1948-05-13
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Granted: 1951-09-18
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Expires: 1968-05-13
Abstract
No abstract record available.
Inventors
- 👤 Carswell Allan Bryson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:45
CPC Classifications
F; F24; F24H; F24H3/00; F24H3/02; F24H3/06; F24H3/08; F24H3/087
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US315040A
Cited
US867572A
Cited
US2296185A
Cited
US2363742A
Cited
US2313933A
Cited
US2404592A
Cited
US2376140A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-09-17 | 1955-03-19 | 1955-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-09-17 | 1959-03-19 | 1959-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-09-17 | 1963-03-19 | 1963-09-18 | $7700.00 | Window Closed / Lapsed |