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FR545288A
Expired / Lapsed
FR
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Rotary helicopter
Assignee: Pierre Hees
•
Filing: 1921-12-28
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Granted: 1922-10-09
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Expires: 1941-12-28
Abstract
No abstract record available.
Inventors
- 👤 Pierre Hees
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-10-28 12:49
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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