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Patent US2225826A successfully refreshed from Google Patents.
US2225826A
Expired / Lapsed
US
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Lens surfacing machine
Assignee: Individual
•
Filing: 1940-01-29
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Granted: 1940-12-24
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Expires: 1960-01-29
Abstract
No abstract record available.
Inventors
- 👤 Robert F Duffens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:23
CPC Classifications
B; B24; B24B; B24B13/00; B24B13/02
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) | 1943-12-24 | 1944-06-24 | 1944-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-12-24 | 1948-06-24 | 1948-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-12-24 | 1952-06-24 | 1952-12-24 | $7700.00 | Window Closed / Lapsed |