Patent US2544971A successfully refreshed from Google Patents.
US2544971A
Expired / Lapsed
US
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Paper stock refining machine
Assignee: Individual
•
Filing: 1947-09-17
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Granted: 1951-03-13
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Expires: 1967-09-17
Abstract
No abstract record available.
Inventors
- 👤 Wells Harold Donald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:52
CPC Classifications
B; B02; B02C; B02C2/00; B02C2/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US282098A
Cited
US411251A
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US1350691A
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US1730908A
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US1814452A
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DE619102C
Cited
US1971335A
Cited
US1961808A
Cited
US1939747A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-03-12 | 1954-09-11 | 1955-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-12 | 1958-09-11 | 1959-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-12 | 1962-09-11 | 1963-03-13 | $7700.00 | Window Closed / Lapsed |