US2684461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct current electric transmission system
Assignee: ERA Patents Ltd
•
Filing: 1952-02-29
•
Granted: 1954-07-20
•
Expires: 1972-02-29
Abstract
No abstract record available.
Inventors
- 👤 Busemann Felix
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:35
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/40; H02M5/42; H02M5/44; H02M5/443; H02M5/447
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2532107A
Cited
US2534036A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-07-19 | 1958-01-18 | 1958-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-07-19 | 1962-01-18 | 1962-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-07-19 | 1966-01-18 | 1966-07-20 | $7700.00 | Window Closed / Lapsed |