Patent US3520979A successfully refreshed from Google Patents.
US3520979A
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US
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Electrode circuit for hex electric furnace
Assignee: PENELECTRO Ltd
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Filing: 1968-02-26
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Granted: 1970-07-21
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Expires: 1988-02-26
Abstract
No abstract record available.
Inventors
- 👤 Frederick Scarfe
- 👤 Harvey Larry Penberthy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 06:32
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/0019; H05B3/0023; C; C03; C03B; C03B5/00; C03B5/02; C03B5/027; C03B5/0275; C03B5/03; C03B5/031; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2749378A
Cited
US2993079A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-20 | 1974-01-19 | 1974-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-20 | 1978-01-19 | 1978-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-20 | 1982-01-19 | 1982-07-21 | $7700.00 | Window Closed / Lapsed |