US2455738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic air filter and circulator
Assignee: Individual
•
Filing: 1945-06-30
•
Granted: 1948-12-07
•
Expires: 1965-06-30
Abstract
No abstract record available.
Inventors
- 👤 George W Crise
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:42
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/34; B03C3/66
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) | 1951-12-07 | 1952-06-07 | 1952-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-07 | 1956-06-07 | 1956-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-07 | 1960-06-07 | 1960-12-07 | $7700.00 | Window Closed / Lapsed |