US3404241A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helical scan magnetic tape apparatus with self-energized air lubrication
Assignee: Ampex Corp
•
Filing: 1965-02-12
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Granted: 1968-10-01
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Expires: 1985-02-12
Abstract
No abstract record available.
Inventors
- 👤 John H Streets
- 👤 Alexander R Maxey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:09
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/60; G11B15/61
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3075049A
Cited
US3159501A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-10-01 | 1972-04-01 | 1972-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-10-01 | 1976-04-01 | 1976-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-10-01 | 1980-04-01 | 1980-10-01 | $7700.00 | Window Closed / Lapsed |