Patent US2638507A successfully refreshed from Google Patents.
US2638507A
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US
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Magnetic record eraser
Assignee: General Precision Laboratory Inc
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Filing: 1950-08-24
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Granted: 1953-05-12
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Expires: 1970-08-24
Abstract
No abstract record available.
Inventors
- 👤 Eugene H Lombardi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:48
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/027; G11B5/03
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE652011C
Cited
US1837586A
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FR691711A
Cited
US2288862A
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US2535481A
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US2538892A
Cited
US2498423A
Cited
US2535712A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-11 | 1956-11-10 | 1957-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-11 | 1960-11-10 | 1961-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-11 | 1964-11-10 | 1965-05-12 | $7700.00 | Window Closed / Lapsed |