Patent US4861971A successfully refreshed from Google Patents.
US2771602A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Absorption device for electro-magnetic waves
Assignee: ELAC Electroacustic GmbH
•
Filing: 1954-02-12
•
Granted: 1956-11-20
•
Expires: 1974-02-12
Abstract
No abstract record available.
Inventors
- 👤 Kuhnhold Rudolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:44
CPC Classifications
H; H01; H01Q; H01Q17/00; H01Q17/008
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) | 1959-11-20 | 1960-05-21 | 1960-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-11-20 | 1964-05-21 | 1964-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-11-20 | 1968-05-21 | 1968-11-20 | $7700.00 | Window Closed / Lapsed |