Patent US428378A successfully refreshed from Google Patents.
US428378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric furnace for melting metals
Assignee: —
•
Filing: —
•
Granted: 1890-05-20
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Expires: 1907-05-20
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:12
CPC Classifications
F; F27; F27B; F27B14/00; F27B14/04; C; C21; C21C; C21C7/00; C21C7/10
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) | 1893-05-19 | 1893-11-18 | 1894-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1897-05-19 | 1897-11-18 | 1898-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1901-05-20 | 1901-11-19 | 1902-05-21 | $7700.00 | Window Closed / Lapsed |