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US2398045A
Expired / Lapsed
US
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Zig-zag filter construction
Assignee: Air Maze Corp
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Filing: 1943-02-01
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Granted: 1946-04-09
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Expires: 1963-02-01
Abstract
No abstract record available.
Inventors
- 👤 Oliver H Schaaf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:45
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/52; B01D46/521; B01D46/522; B01D29/00; B01D29/11; B01D29/13; B01D29/15; B01D29/21; B01D46/10
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) | 1949-04-08 | 1949-10-08 | 1950-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1953-04-08 | 1953-10-08 | 1954-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1957-04-08 | 1957-10-08 | 1958-04-09 | $7700.00 | Window Closed / Lapsed |