US2780894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Twist drill sharpening attachment for tool grinder
Assignee: Nordberg Manufacturing Co
•
Filing: 1954-04-28
•
Granted: 1957-02-12
•
Expires: 1974-04-28
Abstract
No abstract record available.
Inventors
- 👤 Clyde K Jensch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:50
CPC Classifications
B; B24; B24B; B24B3/00; B24B3/24; B24B3/247
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US622212A
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US1093028A
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CH236272A
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US2511055A
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US2583159A
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US2632983A
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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) | 1960-02-12 | 1960-08-13 | 1961-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-02-12 | 1964-08-13 | 1965-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-02-12 | 1968-08-13 | 1969-02-12 | $7700.00 | Window Closed / Lapsed |