Patent DE1573076A1 successfully refreshed from Google Patents.
US2971157A
Expired / Lapsed
US
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Electronic commutators
Assignee: International Business Machines Corp
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Filing: 1956-03-15
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Granted: 1961-02-07
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Expires: 1976-03-15
Abstract
No abstract record available.
Inventors
- 👤 Leonard R Harper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:44
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/04; H04J3/042; H03; H03K; H03K21/00
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) | 1964-02-07 | 1964-08-08 | 1965-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-02-07 | 1968-08-08 | 1969-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-02-07 | 1972-08-08 | 1973-02-07 | $7700.00 | Window Closed / Lapsed |