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Patent US2567709A successfully refreshed from Google Patents.
US2567709A
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Electrical precipitator with dual discharge electrodes
Assignee: Research Corp
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Filing: 1948-08-18
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Granted: 1951-09-11
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Expires: 1968-08-18
Abstract
No abstract record available.
Inventors
- 👤 Carl W J Hedberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:20
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/02; B03C3/04; B03C3/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-09-10 | 1955-03-12 | 1955-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-09-10 | 1959-03-12 | 1959-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-09-10 | 1963-03-12 | 1963-09-11 | $7700.00 | Window Closed / Lapsed |