Patent US1454841A successfully refreshed from Google Patents.
US2991981A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cyclones
Assignee: Hoechst AG
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Filing: 1957-10-15
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Granted: 1961-07-11
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Expires: 1977-10-15
Abstract
No abstract record available.
Inventors
- 👤 Andersen Heinz-Erhardt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:39
CPC Classifications
B; B60; B60G; B60G15/00; B60G15/08; B60G15/12; B04; B04C; B04C5/00; B04C5/20; B04C5/24; F; F16; F16F; F16F9/00; F16F9/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2437294A
Cited
US2536752A
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US2424122A
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US2519028A
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US2487633A
Cited
GB641357A
Cited
US2676667A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-07-10 | 1965-01-09 | 1965-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-07-10 | 1969-01-09 | 1969-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-07-10 | 1973-01-09 | 1973-07-11 | $7700.00 | Window Closed / Lapsed |