US2631789A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording apparatus
Assignee: J P SEEBURG Corp
•
Filing: 1946-12-19
•
Granted: 1953-03-17
•
Expires: 1966-12-19
Abstract
No abstract record available.
Inventors
- 👤 Roy H Watterlohn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 05:27
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/18; G11B15/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1943453A
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US663605A
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US852148A
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US1560721A
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US1881383A
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US1939181A
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US2091756A
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US2084134A
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US2519245A
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US2427193A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-03-16 | 1956-09-15 | 1957-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-03-16 | 1960-09-15 | 1961-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-03-16 | 1964-09-15 | 1965-03-17 | $7700.00 | Window Closed / Lapsed |