US2243296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter element and method of making the same
Assignee: Individual
•
Filing: 1938-06-01
•
Granted: 1941-05-27
•
Expires: 1958-06-01
Abstract
No abstract record available.
Inventors
- 👤 Ernest J Sweetland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:06
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14
Claims Analysis
Total Claims: 0
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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) | 1944-05-26 | 1944-11-25 | 1945-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-05-26 | 1948-11-25 | 1949-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-05-26 | 1952-11-25 | 1953-05-27 | $7700.00 | Window Closed / Lapsed |