Patent US1681276A successfully refreshed from Google Patents.
US1681276A
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Fluid filter for the absorption of certain radiations
Assignee: SARAH G BELL
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Filing: 1924-12-01
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Granted: 1928-08-21
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Expires: 1944-12-01
Abstract
No abstract record available.
Inventors
- 👤 Sarah G Bell
- 👤 Wolfe Walter George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:20
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/16
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) | 1931-08-21 | 1932-02-20 | 1932-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-08-21 | 1936-02-20 | 1936-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-08-21 | 1940-02-20 | 1940-08-21 | $7700.00 | Window Closed / Lapsed |