Patent DE552000C successfully refreshed from Google Patents.
DE552000C
Expired / Lapsed
DE
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Measuring device for testing the air resistance of breathing filters
Assignee: Heinr & Bernh Draeger
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Filing: 1928-06-09
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Granted: 1932-06-08
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Expires: 1948-06-09
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-27 16:49
CPC Classifications
A; A62; A62B; A62B27/00
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Total Claims: 0
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References Cited (Backward Citations)
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