Patent US1428839A successfully refreshed from Google Patents.
US1428839A
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Ionizing electrode for precipitating apparatus
Assignee: Westinghouse Electric Corp
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Filing: 1919-02-25
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Granted: 1922-09-12
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Expires: 1939-02-25
Abstract
No abstract record available.
Inventors
- 👤 Charles Le G Fortescue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:17
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/34; B03C3/66
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) | 1925-09-11 | 1926-03-13 | 1926-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1929-09-11 | 1930-03-13 | 1930-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1933-09-11 | 1934-03-13 | 1934-09-12 | $7700.00 | Window Closed / Lapsed |