Patent US2620787A successfully refreshed from Google Patents.
US2620787A
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Forced air flow unit air-heating furnace
Assignee: Individual
•
Filing: 1946-10-28
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Granted: 1952-12-09
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Expires: 1966-10-28
Abstract
No abstract record available.
Inventors
- 👤 John S Zink
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:42
CPC Classifications
F; F24; F24H; F24H3/00; F24H3/02; F24H3/06; F24H3/065
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2172667A
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US2470860A
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US1583238A
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US2172399A
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US2263098A
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US2363742A
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US2386160A
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US2408691A
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US2411663A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-09 | 1956-06-09 | 1956-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-09 | 1960-06-09 | 1960-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-09 | 1964-06-09 | 1964-12-09 | $7700.00 | Window Closed / Lapsed |