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US3029488A
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US
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Earth boring equipment
Assignee: Dowty Rotol Ltd
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Filing: 1960-05-16
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Granted: 1962-04-17
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Expires: 1980-05-16
Abstract
No abstract record available.
Inventors
- 👤 Richard N Knighis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:26
CPC Classifications
E; E21; E21B; E21B19/00; E21B19/10; Y; Y10; Y10T; Y10T279/00; Y10T279/17; Y10T279/17666; Y10T279/17692; Y10T279/17717
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US689658A
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US684594A
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US1280850A
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US1731128A
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US1986284A
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US2256155A
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US2700201A
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US2755758A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-04-16 | 1965-10-16 | 1966-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-04-16 | 1969-10-16 | 1970-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-04-16 | 1973-10-16 | 1974-04-17 | $7700.00 | Window Closed / Lapsed |