US2474712A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable filter screen
Assignee: —
•
Filing: —
•
Granted: 1949-06-28
•
Expires: 1966-06-28
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:32
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/22; G02B5/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US504890A
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US695606A
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US1269422A
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US1515389A
Cited
US1780773A
Cited
US1782328A
Cited
AU820632A
Cited
US1940040A
Cited
US2300251A
Cited
US2373214A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-06-27 | 1952-12-27 | 1953-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-06-27 | 1956-12-27 | 1957-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-06-27 | 1960-12-27 | 1961-06-28 | $7700.00 | Window Closed / Lapsed |