US2579217A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Harmonic electrical alternating-current generation
Assignee: FERRIS INSTR LAB
•
Filing: 1947-02-07
•
Granted: 1951-12-18
•
Expires: 1967-02-07
Abstract
No abstract record available.
Inventors
- 👤 Howard J Tyzzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:33
CPC Classifications
H; H03; H03B; H03B19/00; H03B19/06; H03B19/08; H03B19/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-17 | 1955-06-18 | 1955-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-17 | 1959-06-18 | 1959-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-17 | 1963-06-18 | 1963-12-18 | $7700.00 | Window Closed / Lapsed |