Patent US2391222A successfully refreshed from Google Patents.
US2391222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making electromagnetic devices
Assignee: Nokia Bell Labs
•
Filing: 1944-06-22
•
Granted: 1945-12-18
•
Expires: 1964-06-22
Abstract
No abstract record available.
Inventors
- 👤 David G Blattner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:43
CPC Classifications
H; H01; H01H; H01H50/00; H01H50/16; H01H50/36; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49075
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1948-12-17 | 1949-06-18 | 1949-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1952-12-17 | 1953-06-18 | 1953-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1956-12-17 | 1957-06-18 | 1957-12-18 | $7700.00 | Window Closed / Lapsed |