Patent US3438168A successfully refreshed from Google Patents.
US2695337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power audio amplifier
Assignee: Individual
•
Filing: 1950-02-20
•
Granted: 1954-11-23
•
Expires: 1970-02-20
Abstract
No abstract record available.
Inventors
- 👤 Richard S Burwen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:34
CPC Classifications
H; H03; H03G; H03G5/00; H03G5/02; H03G5/04; H03G5/06; H03G5/08
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2072708A
Cited
GB453574A
Cited
US2186571A
Cited
US2245598A
Cited
US2282382A
Cited
US2282383A
Cited
US2433330A
Cited
US2361602A
Cited
US2505254A
Cited
US2586167A
Cited
US2529459A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-11-22 | 1958-05-24 | 1958-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-11-22 | 1962-05-24 | 1962-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-11-22 | 1966-05-24 | 1966-11-23 | $7700.00 | Window Closed / Lapsed |