Patent FR844211A successfully refreshed from Google Patents.
FR844211A
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FR
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Improvements to sound reproducing devices such as loudspeakers
Assignee: Charles Tourne
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Filing: 1938-03-31
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Granted: 1939-07-20
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Expires: 1958-03-31
Abstract
No abstract record available.
Inventors
- 👤 Charles Tourne
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-04 19:40
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/02; H04R9/04; H04R9/041
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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