Patent US2237569A successfully refreshed from Google Patents.
US2237569A
Expired / Lapsed
US
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Induction heater
Assignee: Individual
•
Filing: 1940-08-03
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Granted: 1941-04-08
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Expires: 1960-08-03
Abstract
No abstract record available.
Inventors
- 👤 Einar G Lofgren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:30
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/02; H05B6/10; H05B6/105; H05B6/108; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49073
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) | 1944-04-07 | 1944-10-07 | 1945-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-04-07 | 1948-10-07 | 1949-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-04-07 | 1952-10-07 | 1953-04-08 | $7700.00 | Window Closed / Lapsed |