US1832608A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diaphragm for acoustic devices
Assignee: Individual
•
Filing: 1930-11-12
•
Granted: 1931-11-17
•
Expires: 1950-11-12
Abstract
No abstract record available.
Inventors
- 👤 Alexander I Abrahams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:49
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/02; H04R7/12; H04R7/127
Claims Analysis
Total Claims: 0
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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) | 1934-11-16 | 1935-05-18 | 1935-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-11-16 | 1939-05-18 | 1939-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-11-16 | 1943-05-18 | 1943-11-17 | $7700.00 | Window Closed / Lapsed |