US2815824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic precipitator
Assignee: Research Corp
•
Filing: 1955-05-12
•
Granted: 1957-12-10
•
Expires: 1975-05-12
Abstract
No abstract record available.
Inventors
- 👤 John A Armstrong
- 👤 Cooperman Philip
- 👤 Harry J White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:20
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/34; B03C3/36; B03C3/40; B03C3/45; B03C3/47
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1960-12-09 | 1961-06-10 | 1961-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-09 | 1965-06-10 | 1965-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-09 | 1969-06-10 | 1969-12-10 | $7700.00 | Window Closed / Lapsed |