US2935690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistor tube switching circuits
Assignee: International Business Machines Corp
•
Filing: 1955-01-13
•
Granted: 1960-05-03
•
Expires: 1975-01-13
Abstract
No abstract record available.
Inventors
- 👤 Carl A Bergfors
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:53
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/28; H03K3/281
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2717961A
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US2562171A
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US2695959A
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US2701309A
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US2506439A
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US2605306A
Cited
US2707752A
Cited
US2623170A
Cited
US2744198A
Cited
US2628310A
Cited
US2761965A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-05-03 | 1963-11-02 | 1964-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-05-03 | 1967-11-02 | 1968-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-05-03 | 1971-11-02 | 1972-05-03 | $7700.00 | Window Closed / Lapsed |