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US3175166A
Expired / Lapsed
US
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Direct-current switch employing pnpn controlled rectifiers
Assignee: AT&T Inc
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Filing: 1961-12-27
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Granted: 1965-03-23
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Expires: 1981-12-27
Abstract
No abstract record available.
Inventors
- 👤 Lester F Bird
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:17
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/722; H03K17/723
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-03-22 | 1968-09-21 | 1969-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-22 | 1972-09-21 | 1973-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-22 | 1976-09-21 | 1977-03-23 | $7700.00 | Window Closed / Lapsed |