US1640436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amplifying system
Assignee: General Electric Co
•
Filing: 1925-11-14
•
Granted: 1927-08-30
•
Expires: 1945-11-14
Abstract
No abstract record available.
Inventors
- 👤 Frederick C Barton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:14
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/14; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1607; H04B1/1623
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) | 1930-08-29 | 1931-02-28 | 1931-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-08-29 | 1935-02-28 | 1935-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-08-29 | 1939-02-28 | 1939-08-30 | $7700.00 | Window Closed / Lapsed |