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Patent USRE18971E successfully refreshed from Google Patents.
USRE18971E
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct-current voltage transfor
Assignee: —
•
Filing: —
•
Granted: 1933-10-24
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Expires: 1950-10-24
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:19
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/22; H02M3/34; H02M3/38; H02M3/42
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) | 1936-10-23 | 1937-04-24 | 1937-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-10-23 | 1941-04-24 | 1941-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-10-23 | 1945-04-24 | 1945-10-24 | $7700.00 | Window Closed / Lapsed |