US2492255A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sealed-coil type vibratory magnet loudspeaker
Assignee: Individual
•
Filing: 1944-12-26
•
Granted: 1949-12-27
•
Expires: 1964-12-26
Abstract
No abstract record available.
Inventors
- 👤 John O Angehrn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:18
CPC Classifications
H; H04; H04R; H04R11/00; H04R11/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1402546A
Cited
US1585022A
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US2006847A
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US1795948A
Cited
US1953248A
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US2073561A
Cited
US2110153A
Cited
US2249158A
Cited
US2348225A
Cited
US2346429A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-26 | 1953-06-27 | 1953-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-26 | 1957-06-27 | 1957-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-26 | 1961-06-27 | 1961-12-27 | $7700.00 | Window Closed / Lapsed |