Patent US4521567A successfully refreshed from Google Patents.
Patent US2223188A successfully refreshed from Google Patents.
US2223188A
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Signaling system
Assignee: General Electric Co
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Filing: 1938-02-01
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Granted: 1940-11-26
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Expires: 1958-02-01
Abstract
No abstract record available.
Inventors
- 👤 Norton F Shofstall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:41
CPC Classifications
H; H03; H03J; H03J3/00; H03J3/02; H03J3/12; H03J3/14; H03F; H03F1/00; H03F1/08; H03G; H03G3/00; H03G3/20; H03G3/22
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) | 1943-11-26 | 1944-05-27 | 1944-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-11-26 | 1948-05-27 | 1948-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-11-26 | 1952-05-27 | 1952-11-26 | $7700.00 | Window Closed / Lapsed |