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US3018846A
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Electrostatic precipitators
Assignee: American Air Filter Co Inc
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Filing: 1958-03-03
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Granted: 1962-01-30
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Expires: 1978-03-03
Abstract
No abstract record available.
Inventors
- 👤 Lawrence J Czerwonka
- 👤 Richard D Rivers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:53
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/34; B03C3/40; B03C3/45; B03C3/47
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US856131A
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US1697316A
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GB385508A
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FR773867A
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US2542262A
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US2616142A
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US2642952A
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DE893555C
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-01-29 | 1965-07-31 | 1966-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-01-29 | 1969-07-31 | 1970-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-01-29 | 1973-07-31 | 1974-01-30 | $7700.00 | Window Closed / Lapsed |