Patent DE659079C successfully refreshed from Google Patents.
DE659079C
Expired / Lapsed
DE
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Screw connection between drill rod and drill bit for rock percussion drill
Assignee: HERMANN PRAGER
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Filing: 1935-09-19
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Granted: 1938-11-24
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Expires: 1955-09-19
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-11-05 14:48
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/02; E21B17/04; E21B17/042
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