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US2716564A
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US
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Arrangement for attaching a drill crown to a drill steel or drill steels to each other
Assignee: Sandvik AB
•
Filing: 1950-08-31
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Granted: 1955-08-30
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Expires: 1970-08-31
Abstract
No abstract record available.
Inventors
- 👤 Lofqvist Bengt Erik Ragnwald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:43
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/02; E21B17/04; E21B17/046; Y; Y10; Y10T; Y10T403/00; Y10T403/57; Y10T403/5733
Claims Analysis
Total Claims: 0
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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) | 1958-08-29 | 1959-02-28 | 1959-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-08-29 | 1963-02-28 | 1963-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-08-29 | 1967-02-28 | 1967-08-30 | $7700.00 | Window Closed / Lapsed |