US2422591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetizable core
Assignee: SIGMUND Corp
•
Filing: 1943-04-12
•
Granted: 1947-06-17
•
Expires: 1963-04-12
Abstract
No abstract record available.
Inventors
- 👤 Frank J Sigmund
- 👤 William S Hlavin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:41
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/32; H02K3/34; H02K3/345
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US422550A
Cited
US464026A
Cited
US1315936A
Cited
US1678380A
Cited
US1875207A
Cited
US1974406A
Cited
GB451776A
Cited
US2124610A
Cited
US2128544A
Cited
US2169097A
Cited
US2320866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-06-16 | 1950-12-16 | 1951-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-06-16 | 1954-12-16 | 1955-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-06-16 | 1958-12-16 | 1959-06-17 | $7700.00 | Window Closed / Lapsed |