Patent US2609448A successfully refreshed from Google Patents.
US2609448A
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Electrical differentiating circuit
Assignee: AC Cossor Ltd
•
Filing: 1945-06-01
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Granted: 1952-09-02
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Expires: 1965-06-01
Abstract
No abstract record available.
Inventors
- 👤 Bedford Leslie Herbert
- 👤 Jofeh Lionel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:48
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/30; G; G06; G06G; G06G7/00; G06G7/12; G06G7/14; G06G7/18; G06G7/182
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1435009A
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US2377903A
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US2217957A
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US2437951A
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US2439198A
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US2450352A
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US2437313A
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US2236134A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-09-02 | 1956-03-03 | 1956-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-09-02 | 1960-03-03 | 1960-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-09-02 | 1964-03-03 | 1964-09-02 | $7700.00 | Window Closed / Lapsed |