Patent US2839189A successfully refreshed from Google Patents.
US2839189A
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Electrostatic separation method
Assignee: Quaker Oats Co
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Filing: 1954-02-01
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Granted: 1958-06-17
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Expires: 1974-02-01
Abstract
No abstract record available.
Inventors
- 👤 Herbert B Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:28
CPC Classifications
B; B03; B03C; B03C7/00; B03C7/02; B03C7/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1153182A
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US1549875A
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US2135716A
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US2197864A
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US2197865A
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US2317210A
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US2445229A
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US2357658A
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US2559076A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-16 | 1961-12-16 | 1962-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-16 | 1965-12-16 | 1966-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-16 | 1969-12-16 | 1970-06-17 | $7700.00 | Window Closed / Lapsed |