US2531443A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control apparatus for alternating current
Assignee: Fkg Fritz Kesselring Geratebau AG
•
Filing: 1947-06-13
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Granted: 1950-11-28
•
Expires: 1967-06-13
Abstract
No abstract record available.
Inventors
- 👤 Kesselring Fritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:51
CPC Classifications
H; H01; H01H; H01H9/00; H01H9/54; H01H9/56; H01H33/00; H01H33/006
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1287232A
Cited
US1761006A
Cited
US1967850A
Cited
US1967849A
Cited
US2225763A
Cited
US2261686A
Cited
US2241973A
Cited
US2299561A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |