US2766880A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of fine-grained portions from granular materials
Assignee: Ruhrchemie AG
•
Filing: 1952-07-29
•
Granted: 1956-10-16
•
Expires: 1972-07-29
Abstract
No abstract record available.
Inventors
- 👤 Schaub Franz
- 👤 Tramm Heinrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:03
CPC Classifications
B; B07; B07B; B07B4/00; B07B4/02; B07B4/025
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
DE346574C
Cited
DE295828C
Cited
US940469A
Cited
FR464928A
Cited
US1522151A
Cited
US1569468A
Cited
DE453358C
Cited
US2421840A
Cited
US2446786A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-10-16 | 1960-04-16 | 1960-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-16 | 1964-04-16 | 1964-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-16 | 1968-04-16 | 1968-10-16 | $7700.00 | Window Closed / Lapsed |