US2579530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Four-wire to two-wire connecting circuit
Assignee: International Standard Electric Corp
•
Filing: 1948-04-28
•
Granted: 1951-12-25
•
Expires: 1968-04-28
Abstract
No abstract record available.
Inventors
- 👤 Wright Esmond Philip Goodwin
- 👤 Weir Donald Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:20
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/54; H04B1/58
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1829803A
Cited
US1961279A
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US1986515A
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US2145095A
Cited
GB489545A
Cited
US2322833A
Cited
GB560807A
Cited
US2462144A
Cited
US2498723A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-24 | 1955-06-25 | 1955-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-24 | 1959-06-25 | 1959-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-24 | 1963-06-25 | 1963-12-25 | $7700.00 | Window Closed / Lapsed |