Patent US1140940A successfully refreshed from Google Patents.
Patent US2619280A successfully refreshed from Google Patents.
US2619280A
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Centrifugal contactor and method of contacting
Assignee: Shell Development Co
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Filing: 1948-10-25
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Granted: 1952-11-25
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Expires: 1968-10-25
Abstract
No abstract record available.
Inventors
- 👤 Redlich Otto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:57
CPC Classifications
B; B04; B04B; B04B5/00; B04B5/06; B01; B01D; B01D11/00; B01D11/04; B01D11/0446; B01D11/0461
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2209577A
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US2281616A
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US2313541A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-11-25 | 1956-05-26 | 1956-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-25 | 1960-05-26 | 1960-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-25 | 1964-05-26 | 1964-11-25 | $7700.00 | Window Closed / Lapsed |