US2457740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluidproof winding element
Assignee: SIGMUND Corp
•
Filing: 1944-12-02
•
Granted: 1948-12-28
•
Expires: 1964-12-02
Abstract
No abstract record available.
Inventors
- 👤 Frank J Sigmund
- 👤 William S Hlavin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:25
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/44
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1137278A
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US1524558A
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US1675419A
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US1925891A
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US2128544A
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US2173726A
Cited
US2417746A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-12-28 | 1952-06-28 | 1952-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-28 | 1956-06-28 | 1956-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-28 | 1960-06-28 | 1960-12-28 | $7700.00 | Window Closed / Lapsed |