US2489862A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Damping for dynamic loudspeakers
Assignee: General Electric Co
•
Filing: 1943-01-07
•
Granted: 1949-11-29
•
Expires: 1963-01-07
Abstract
No abstract record available.
Inventors
- 👤 Ellsworth D Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 01:49
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/02; H04R9/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US989958A
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US1648120A
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US1904537A
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US1658349A
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US1734944A
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FR709205A
Cited
US1952167A
Cited
US2007747A
Cited
GB548278A
Cited
US2318517A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-11-28 | 1953-05-30 | 1953-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-11-28 | 1957-05-30 | 1957-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-11-28 | 1961-05-30 | 1961-11-29 | $7700.00 | Window Closed / Lapsed |