Patent US2879115A successfully refreshed from Google Patents.
Patent US214339A successfully refreshed from Google Patents.
US2981871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Permanent magnet
Assignee: US Philips Corp
•
Filing: 1957-08-19
•
Granted: 1961-04-25
•
Expires: 1977-08-19
Abstract
No abstract record available.
Inventors
- 👤 Westmijze Willem Klaas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:07
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/10; H01F7/00; H01F7/02; H01F7/0205; H01F7/021
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |