US2978545A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic playback heads
Assignee: McGraw Edison Co
•
Filing: 1956-10-15
•
Granted: 1961-04-04
•
Expires: 1976-10-15
Abstract
No abstract record available.
Inventors
- 👤 Dennis H Howling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:00
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/07; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/142
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2553490A
Cited
US2768243A
Cited
US2702316A
Cited
US2736822A
Cited
US2714182A
Cited
US2907834A
Cited
US2866013A
Cited
US2900451A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-03 | 1964-10-03 | 1965-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-03 | 1968-10-03 | 1969-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-03 | 1972-10-03 | 1973-04-04 | $7700.00 | Window Closed / Lapsed |