Patent US2736875A successfully refreshed from Google Patents.
Patent US2688520A successfully refreshed from Google Patents.
US2688520A
Expired / Lapsed
US
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Pressure seal for rotating shafts
Assignee: Union Oil Company of California
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Filing: 1950-09-11
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Granted: 1954-09-07
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Expires: 1970-09-11
Abstract
No abstract record available.
Inventors
- 👤 James M Covington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:26
CPC Classifications
F; F16; F16C; F16C33/00; F16C33/72; F16C33/76; F16C33/78
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1396327A
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US1755440A
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US1835877A
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US2390977A
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US2388570A
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US2423436A
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US2481430A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-09-06 | 1958-03-08 | 1958-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-09-06 | 1962-03-08 | 1962-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-09-06 | 1966-03-08 | 1966-09-07 | $7700.00 | Window Closed / Lapsed |