Patent US3444667A successfully refreshed from Google Patents.
US3444667A
Expired / Lapsed
US
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Electrostatic precipitator
Assignee: Northrop Grumman Guidance and Electronics Co Inc
•
Filing: 1968-03-01
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Granted: 1969-05-20
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Expires: 1988-03-01
Abstract
No abstract record available.
Inventors
- 👤 Doyle D Mullin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:54
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/02; B03C3/04; B03C3/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2064587A
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US2336625A
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US2675090A
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US2949167A
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US2868322A
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US3035445A
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US3232094A
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US3148146A
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US3392512A
Cited
US3401503A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-05-19 | 1972-11-18 | 1973-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-05-19 | 1976-11-18 | 1977-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-05-19 | 1980-11-18 | 1981-05-20 | $7700.00 | Window Closed / Lapsed |