US2542852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant voltage power supply
Assignee: Duracell Inc USA
•
Filing: 1944-10-14
•
Granted: 1951-02-20
•
Expires: 1964-10-14
Abstract
No abstract record available.
Inventors
- 👤 Robert O Whitesell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:29
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/12; G05F1/32; G05F1/33
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1650072A
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US1965439A
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US2085060A
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US2084899A
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US2157977A
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US2138732A
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US2322130A
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US2306998A
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US2346997A
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US2331131A
Cited
US2331411A
Cited
US2450012A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-19 | 1954-08-21 | 1955-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-19 | 1958-08-21 | 1959-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-19 | 1962-08-21 | 1963-02-20 | $7700.00 | Window Closed / Lapsed |