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US3548290A
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Proportional control systems using two capacitors in series in the firing circuit with the smaller one shunted by a current drain device
Assignee: Cutler Hammer Inc
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Filing: 1967-07-31
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Granted: 1970-12-15
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Expires: 1987-07-31
Abstract
No abstract record available.
Inventors
- 👤 Merle R Swinehart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:54
CPC Classifications
H; H02; H02P; H02P25/00; H02P25/02; H02P25/10; H02P25/14; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/20; G05D23/24; Y; Y10; Y10S; Y10S323/00; Y10S323/902
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3242346A
Cited
US3244964A
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US3368140A
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US3344311A
Cited
US3410105A
Cited
US3385077A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-12-14 | 1974-06-15 | 1974-12-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-12-14 | 1978-06-15 | 1978-12-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-12-14 | 1982-06-15 | 1982-12-15 | $7700.00 | Window Closed / Lapsed |