Patent US2176720A successfully refreshed from Google Patents.
US2176720A
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US
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Electrical signaling system
Assignee: Associated Telephone and Telegraph Co
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Filing: 1935-07-05
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Granted: 1939-10-17
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Expires: 1955-07-05
Abstract
No abstract record available.
Inventors
- 👤 Rayner Thomas Robert
- 👤 Burns George Arthur
- 👤 Woodhead Harry Stanley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:59
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/12; G01D5/244; G01D5/245; G01D5/14; G01D5/18; H; H04; H04B; H04B10/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-10-16 | 1943-04-17 | 1943-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-10-16 | 1947-04-17 | 1947-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-10-16 | 1951-04-17 | 1951-10-17 | $7700.00 | Window Closed / Lapsed |