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US2941783A
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Hydraulic earth boring and cyclone separation system
Assignee: Phillips Petroleum Co
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Filing: 1957-07-15
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Granted: 1960-06-21
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Expires: 1977-07-15
Abstract
No abstract record available.
Inventors
- 👤 Donald L Stinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:02
CPC Classifications
E; E21; E21B; E21B21/00; E21B21/06; E21B21/063; E21B21/065
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2156333A
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US2338174A
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US2301371A
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US2555314A
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US2610737A
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US2632631A
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US2756965A
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US2849213A
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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) | 1963-06-21 | 1963-12-21 | 1964-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-21 | 1967-12-21 | 1968-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-21 | 1971-12-21 | 1972-06-21 | $7700.00 | Window Closed / Lapsed |