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US2857050A
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Hydraulic classifier
Assignee: Dorr Oliver Inc
•
Filing: 1955-01-20
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Granted: 1958-10-21
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Expires: 1975-01-20
Abstract
No abstract record available.
Inventors
- 👤 Emil C Nebel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:21
CPC Classifications
B; B03; B03B; B03B5/00; B03B5/62; B03B5/623
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2416450A
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US2708517A
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US2714958A
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US2677463A
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US2714955A
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US2714956A
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US2715463A
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US2715462A
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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) | 1961-10-20 | 1962-04-21 | 1962-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-20 | 1966-04-21 | 1966-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-20 | 1970-04-21 | 1970-10-21 | $7700.00 | Window Closed / Lapsed |