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US1947749A
Expired / Lapsed
US
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Loud speaker
Assignee: RCA Corp
•
Filing: 1929-03-05
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Granted: 1934-02-20
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Expires: 1949-03-05
Abstract
No abstract record available.
Inventors
- 👤 Vermeulen Roelof
- 👤 Urk Arend Thomas Yan
- 👤 Loman Cornelis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:45
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/02; H04R7/12; H04R7/122
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) | 1937-02-19 | 1937-08-21 | 1938-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1941-02-19 | 1941-08-21 | 1942-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1945-02-19 | 1945-08-21 | 1946-02-20 | $7700.00 | Window Closed / Lapsed |