US2220574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for clarifying liquid
Assignee: AT&T Inc
•
Filing: 1937-03-31
•
Granted: 1940-11-05
•
Expires: 1957-03-31
Abstract
No abstract record available.
Inventors
- 👤 John S Little
- 👤 John N Selvig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:11
CPC Classifications
B; B01; B01D; B01D21/00; B01D21/0018; B01D21/0084; B01D21/0096; B01D21/02; B01D21/04; B01D21/24; B01D21/2433; B01D21/30; B01D21/34
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1943-11-05 | 1944-05-06 | 1944-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-11-05 | 1948-05-06 | 1948-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-11-05 | 1952-05-06 | 1952-11-05 | $7700.00 | Window Closed / Lapsed |