Patent DE640336C successfully refreshed from Google Patents.
DE640336C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Process for the production of hollow wire filaments for electric light bulbs
Assignee: Individual
•
Filing: 1931-08-28
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Granted: 1936-12-30
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Expires: 1951-08-28
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-24 04:18
CPC Classifications
H; H01; H01K; H01K3/00; H01K3/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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