Patent US2337133A successfully refreshed from Google Patents.
Patent US2239144A successfully refreshed from Google Patents.
US2239144A
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Assignee: CHICAGO DEV CO
•
Filing: 1938-07-11
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Granted: 1941-04-22
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Expires: 1958-07-11
Abstract
No abstract record available.
Inventors
- 👤 Reginald S Dean
- 👤 Charles W Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:36
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/06; H01F1/08; H01F1/083; B; B22; B22F; B22F9/00; C; C25; C25C; C25C5/00; C25C5/02; Y; Y10; Y10S; Y10S29/00; Y10S29/028
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) | 1944-04-21 | 1944-10-21 | 1945-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-04-21 | 1948-10-21 | 1949-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-04-21 | 1952-10-21 | 1953-04-22 | $7700.00 | Window Closed / Lapsed |