Patent US3577477A successfully refreshed from Google Patents.
DE537840C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
vacuum cleaner
Assignee: FRISTER A G R
•
Filing: 1929-11-30
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Granted: 1931-11-07
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Expires: 1949-11-30
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-27 19:46
CPC Classifications
A; A47; A47L; A47L5/00; A47L5/12; A47L5/22; A47L5/24; A47L9/00; A47L9/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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