US2840380A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recorder sound unit
Assignee: IIT Research Institute
•
Filing: 1952-01-23
•
Granted: 1958-06-24
•
Expires: 1972-01-23
Abstract
No abstract record available.
Inventors
- 👤 Camras Marvin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:24
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/18; G11B15/26; G11B15/34
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2003434A
Cited
FR899195A
Cited
US2482672A
Cited
US2535480A
Cited
US2532761A
Cited
US2518556A
Cited
US2709596A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-23 | 1961-12-23 | 1962-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-23 | 1965-12-23 | 1966-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-23 | 1969-12-23 | 1970-06-24 | $7700.00 | Window Closed / Lapsed |