Patent US1934647A successfully refreshed from Google Patents.
Patent US2144844A successfully refreshed from Google Patents.
US2144844A
Expired / Lapsed
US
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Magnetic telegraphone
Assignee: AT&T Inc
•
Filing: 1936-08-06
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Granted: 1939-01-24
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Expires: 1956-08-06
Abstract
No abstract record available.
Inventors
- 👤 Clarence N Hickman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:47
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/74; G11B5/82; G10; G10H; G10H3/00; G10H3/03; G10H3/08; G10H3/09; G11B25/00; G11B25/04; G11B25/043; Y; Y10; Y10S; Y10S29/00; Y10S29/028
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) | 1942-01-23 | 1942-07-25 | 1943-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-01-23 | 1946-07-25 | 1947-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-01-23 | 1950-07-25 | 1951-01-24 | $7700.00 | Window Closed / Lapsed |