FR664962A
Expired / Lapsed
FR
⏱️ 0.0 years remaining
Improvement in electromagnetic devices particularly applicable to headphones
Assignee: Andre-Auguste Gillet
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Filing: 1928-03-10
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Granted: 1929-09-12
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Expires: 1948-03-10
Abstract
No abstract record available.
Inventors
- 👤 Andre-Auguste Gillet
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-07 14:09
CPC Classifications
H; H04; H04R; H04R13/00; H04R13/02
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Total Claims: 0
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References Cited (Backward Citations)
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