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US2509621A
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US
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Dynamic pressure measurement
Assignee: Shell Development Co
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Filing: 1948-10-26
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Granted: 1950-05-30
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Expires: 1968-10-26
Abstract
No abstract record available.
Inventors
- 👤 Richard B Willoughby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:49
CPC Classifications
G; G01; G01L; G01L23/00; G01L23/08; G01L23/18
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-05-29 | 1953-11-28 | 1954-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-05-29 | 1957-11-28 | 1958-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-05-29 | 1961-11-28 | 1962-05-30 | $7700.00 | Window Closed / Lapsed |