Patent US2393021A successfully refreshed from Google Patents.
US2393021A
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Signaling system
Assignee: Westinghouse Electric Corp
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Filing: 1944-12-27
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Granted: 1946-01-15
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Expires: 1964-12-27
Abstract
No abstract record available.
Inventors
- 👤 Robert C Cheek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:46
CPC Classifications
H; H02; H02J; H02J13/00; H02J13/13; H02J13/1311; Y; Y02; Y02E; Y02E60/00; Y04; Y04S; Y04S40/00; Y04S40/12; Y04S40/121
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) | 1949-01-14 | 1949-07-16 | 1950-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1953-01-14 | 1953-07-16 | 1954-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1957-01-14 | 1957-07-16 | 1958-01-15 | $7700.00 | Window Closed / Lapsed |