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US2764940A
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Oil well pump with diluent delivery means
Assignee: EMSCO Manufacturing Co
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Filing: 1953-07-27
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Granted: 1956-10-02
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Expires: 1973-07-27
Abstract
No abstract record available.
Inventors
- 👤 John A Long
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:01
CPC Classifications
F; F04; F04B; F04B47/00; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0391
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) | 1959-10-02 | 1960-04-02 | 1960-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-02 | 1964-04-02 | 1964-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-02 | 1968-04-02 | 1968-10-02 | $7700.00 | Window Closed / Lapsed |