US2800853A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic shutter for ventilators
Assignee: Nutone Inc
•
Filing: 1956-06-27
•
Granted: 1957-07-30
•
Expires: 1976-06-27
Abstract
No abstract record available.
Inventors
- 👤 Walter A Spear
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:32
CPC Classifications
F; F24; F24F; F24F7/00; F24F7/007; F24F11/00; F24F11/70; F24F11/72; F24F11/74; F24F11/745
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1114675A
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US2239767A
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US2334789A
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US2579395A
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US2739521A
Cited
US2718187A
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US2790377A
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US2741972A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-07-29 | 1961-01-28 | 1961-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-29 | 1965-01-28 | 1965-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-29 | 1969-01-28 | 1969-07-30 | $7700.00 | Window Closed / Lapsed |