Patent US2821029A successfully refreshed from Google Patents.
US2821029A
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Method and apparatus for circulating air
Assignee: ALFORD REFRIGERATED WAREHOUSES
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Filing: 1953-05-25
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Granted: 1958-01-28
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Expires: 1973-05-25
Abstract
No abstract record available.
Inventors
- 👤 Simons Edward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:20
CPC Classifications
F; F26; F26B; F26B9/00; F26B9/06; F26B9/066; A; A23; A23B; A23B2/00; A23B2/80; A23B2/805; A23B2/90
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1330238A
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US1541350A
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US1793086A
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US1757647A
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US1923106A
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US2050226A
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US2079304A
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US2310222A
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US2364722A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-27 | 1961-07-29 | 1962-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-27 | 1965-07-29 | 1966-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-27 | 1969-07-29 | 1970-01-28 | $7700.00 | Window Closed / Lapsed |