US2537657A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Disk type magnetic recordingreproducing apparatus
Assignee: Western Union Telegraph Co
•
Filing: 1945-05-05
•
Granted: 1951-01-09
•
Expires: 1965-05-05
Abstract
No abstract record available.
Inventors
- 👤 Humy Fernand E D
- 👤 Raleigh J Wise
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:06
CPC Classifications
G; G11; G11B; G11B21/00; G11B21/16; G11B21/18; G11B19/00; G11B19/20; G11B19/24; G11B19/247; G11B21/02; G11B21/04; G11B21/06; G11B21/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US939781A
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FR457479A
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FR558207A
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US1827051A
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GB322033A
Cited
US1871752A
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GB512766A
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US2247847A
Cited
US2300209A
Cited
US2353408A
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US2386263A
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US2374704A
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US2361753A
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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) | 1954-01-08 | 1954-07-10 | 1955-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-08 | 1958-07-10 | 1959-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-08 | 1962-07-10 | 1963-01-09 | $7700.00 | Window Closed / Lapsed |