US2694174A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency and voltage control apparatus
Assignee: AT&T Inc
•
Filing: 1950-02-18
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Granted: 1954-11-09
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Expires: 1970-02-18
Abstract
No abstract record available.
Inventors
- 👤 John R Stone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:31
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/245; H02P9/00; H02P9/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1563140A
Cited
US1552781A
Cited
US1691222A
Cited
US1776592A
Cited
US2344608A
Cited
US2496730A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-11-08 | 1958-05-10 | 1958-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-11-08 | 1962-05-10 | 1962-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-11-08 | 1966-05-10 | 1966-11-09 | $7700.00 | Window Closed / Lapsed |