Patent US4559847A successfully refreshed from Google Patents.
US1843291A
Expired / Lapsed
US
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Well drilling and pumping apparatus
Assignee: Shell Petroleum Co Ltd
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Filing: 1928-12-03
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Granted: 1932-02-02
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Expires: 1948-12-03
Abstract
No abstract record available.
Inventors
- 👤 Mcconnell Glenver
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:41
CPC Classifications
E; E21; E21B; E21B1/00; E21B1/02; E21B1/04
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) | 1935-02-01 | 1935-08-03 | 1936-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-02-01 | 1939-08-03 | 1940-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-02-01 | 1943-08-03 | 1944-02-02 | $7700.00 | Window Closed / Lapsed |