US2129751A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Operation of a centrifuge for separating the petroleum oil from sulphuric acid
Assignee: Standard Oil Development Co
•
Filing: 1934-05-25
•
Granted: 1938-09-13
•
Expires: 1954-05-25
Abstract
No abstract record available.
Inventors
- 👤 Alfred A Wells
- 👤 David F Edwards
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:23
CPC Classifications
B; B04; B04B; B04B1/00; B04B1/04; B04B1/08; Y; Y10; Y10S; Y10S494/00; Y10S494/901
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1941-09-12 | 1942-03-14 | 1942-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-09-12 | 1946-03-14 | 1946-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-09-12 | 1950-03-14 | 1950-09-13 | $7700.00 | Window Closed / Lapsed |