US2670460A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Subaudio electrical filter
Assignee: Weston Electric Instrument Corp
•
Filing: 1951-01-09
•
Granted: 1954-02-23
•
Expires: 1971-01-09
Abstract
No abstract record available.
Inventors
- 👤 Roswell W Gilbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:52
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/48; H02; H02J; H02J13/00; H02J13/13; H02J13/1311; H02J13/1313; Y; Y02; Y02E; Y02E60/00; Y04; Y04S; Y04S40/00; Y04S40/12; Y04S40/121
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2560257A
Cited
US786696A
Cited
US1673254A
Cited
US1719484A
Cited
US2112560A
Cited
US2184321A
Cited
GB580388A
Cited
US2622168A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-22 | 1957-08-24 | 1958-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-22 | 1961-08-24 | 1962-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-22 | 1965-08-24 | 1966-02-23 | $7700.00 | Window Closed / Lapsed |