Patent US2661847A successfully refreshed from Google Patents.
US2661847A
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Assignee: Individual
•
Filing: 1950-09-23
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Granted: 1953-12-08
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Expires: 1970-09-23
Abstract
No abstract record available.
Inventors
- 👤 Buettner Arthur J Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:49
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/14; B01D35/143; B01D35/147; B01D35/153; Y; Y10; Y10S; Y10S116/00; Y10S116/42; Y10T; Y10T137/00; Y10T137/794
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1632773A
Cited
US2085173A
Cited
GB495751A
Cited
US2253260A
Cited
US2447142A
Cited
US2494802A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-12-07 | 1957-06-08 | 1957-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-12-07 | 1961-06-08 | 1961-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-12-07 | 1965-06-08 | 1965-12-08 | $7700.00 | Window Closed / Lapsed |