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US1640698A
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Assignee: De Laval Separator Co
•
Filing: 1924-09-04
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Granted: 1927-08-30
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Expires: 1944-09-04
Abstract
No abstract record available.
Inventors
- 👤 Forsberg Erik August
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:43
CPC Classifications
B; B01; B01D; B01D29/00; B01D29/44; B01D29/46; B01D25/00; B01D25/32; B01D25/38
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) | 1930-08-29 | 1931-02-28 | 1931-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-08-29 | 1935-02-28 | 1935-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-08-29 | 1939-02-28 | 1939-08-30 | $7700.00 | Window Closed / Lapsed |