Patent US2491291A successfully refreshed from Google Patents.
US2491291A
Expired / Lapsed
US
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Common trunk selecting means for all relay telephone switches
Assignee: Automatic Electric Laboratories Inc
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Filing: 1945-12-03
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Granted: 1949-12-13
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Expires: 1965-12-03
Abstract
No abstract record available.
Inventors
- 👤 John H Voss
- 👤 Roy W Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:37
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0008
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2133415A
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US2135921A
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US2292371A
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US2302587A
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US2377453A
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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) | 1952-12-12 | 1953-06-13 | 1953-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-12 | 1957-06-13 | 1957-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-12 | 1961-06-13 | 1961-12-13 | $7700.00 | Window Closed / Lapsed |