US2658142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-speed commutator
Assignee: Northrop Grumman Corp
•
Filing: 1951-07-09
•
Granted: 1953-11-03
•
Expires: 1971-07-09
Abstract
No abstract record available.
Inventors
- 👤 John Dale E St
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:24
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/04; H04J3/042
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2169409A
Cited
US2287881A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-11-02 | 1957-05-04 | 1957-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-02 | 1961-05-04 | 1961-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-02 | 1965-05-04 | 1965-11-03 | $7700.00 | Window Closed / Lapsed |