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US1236581A
Expired / Lapsed
US
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Apparatus for extracting values from flue-dust.
Assignee: Individual
•
Filing: 1917-05-16
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Granted: 1917-08-14
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Expires: 1937-05-16
Abstract
No abstract record available.
Inventors
- 👤 Thomas F Mcgrath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:57
CPC Classifications
F; F23; F23J; F23J15/00; F23J15/02; F23J15/04; B; B01; B01F; B01F23/00; B01F23/20; B01F23/23; B01F23/231; B01F23/23105; B01F23/2312; B01F23/23123
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) | 1920-08-13 | 1921-02-12 | 1921-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1924-08-13 | 1925-02-12 | 1925-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1928-08-13 | 1929-02-12 | 1929-08-14 | $7700.00 | Window Closed / Lapsed |