Patent US3277540A successfully refreshed from Google Patents.
US3277540A
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Device for refining foundry sand in a continuous manner
Assignee: Georg Fischer AG
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Filing: 1963-09-06
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Granted: 1966-10-11
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Expires: 1983-09-06
Abstract
No abstract record available.
Inventors
- 👤 Buhrer Erwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:33
CPC Classifications
B; B22; B22C; B22C5/00; B22C5/04; B22C5/0409; B22C5/0459; B01; B01F; B01F29/00; B01F29/40; B01F29/403; B01F29/4033; B01F29/60; B22C5/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1905490A
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GB361700A
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US2176874A
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US2573296A
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US2707314A
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US2783511A
Cited
US2877524A
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US3060496A
Cited
US3151368A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-10-10 | 1970-04-11 | 1970-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-10 | 1974-04-11 | 1974-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-10 | 1978-04-11 | 1978-10-11 | $7700.00 | Window Closed / Lapsed |