Patent US6168631B1 successfully refreshed from Google Patents.
US2033592A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drill pipe protector
Assignee: Individual
•
Filing: 1935-03-13
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Granted: 1936-03-10
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Expires: 1955-03-13
Abstract
No abstract record available.
Inventors
- 👤 Walter L Skeen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:26
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1042; E21B17/105; E21B17/12; Y; Y10; Y10T; Y10T24/00; Y10T24/14; Y10T24/1457; Y10T24/1482
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) | 1939-03-10 | 1939-09-09 | 1940-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1943-03-10 | 1943-09-09 | 1944-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1947-03-10 | 1947-09-09 | 1948-03-10 | $7700.00 | Window Closed / Lapsed |