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US3475674A
Expired / Lapsed
US
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Device for controlling the average output power of a silicon controlled rectifier inverter for induction heating uses
Assignee: Park Ohio Holdings Corp
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Filing: 1967-08-29
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Granted: 1969-10-28
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Expires: 1987-08-29
Abstract
No abstract record available.
Inventors
- 👤 Cecil P Porterfield
- 👤 Graham R Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:52
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/525; H02M7/527; H05; H05B; H05B6/00; H05B6/02; H05B6/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3360712A
Cited
US3325716A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-10-27 | 1973-04-28 | 1973-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-27 | 1977-04-28 | 1977-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-27 | 1981-04-28 | 1981-10-28 | $7700.00 | Window Closed / Lapsed |