DE907535C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Loudspeaker with a damping device placed in the immediate vicinity of the membrane surface due to the amplitudes of the membrane
Assignee: ERICH THIENHAUS DR ING
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Filing: 1937-03-19
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Granted: 1954-03-25
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Expires: 1957-03-19
Abstract
No abstract record available.
Inventors
- 👤 Dr Phil Heinrich Koesters
- 👤 Dr-Ing Erich Thienhaus
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-29 21:56
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/22; H04R2400/00; H04R2400/11
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US18751A
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US1592243A
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US1847456A
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FR714232A
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US1952167A
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AT140149B
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AT146670B
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CH185197A
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AT145460B
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