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US1921731A
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Assignee: CHARMAN
•
Filing: 1931-01-24
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Granted: 1933-08-08
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Expires: 1951-01-24
Abstract
No abstract record available.
Inventors
- 👤 Walter M Charman
- 👤 Heights Cleveland
- 👤 Harry J Darlington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:34
CPC Classifications
B; B22; B22D; B22D7/00; B22D7/06; B22D7/10
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) | 1936-08-07 | 1937-02-06 | 1937-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-08-07 | 1941-02-06 | 1941-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-08-07 | 1945-02-06 | 1945-08-08 | $7700.00 | Window Closed / Lapsed |