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US2820331A
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Grinding device
Assignee: Ammco Tools Inc
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Filing: 1956-02-13
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Granted: 1958-01-21
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Expires: 1976-02-13
Abstract
No abstract record available.
Inventors
- 👤 Billeter Henry Robert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:45
CPC Classifications
B; B24; B24B; B24B19/00; B24B19/26; B24B19/28
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US675609A
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US1095338A
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US1287091A
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US2098267A
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US2289693A
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US2325826A
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US2715799A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |