The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 28, 2000
Filed:
Jul. 29, 1999
Applicant:
Inventors:
Gustav Hanisch, Hochdorf, DE;
Volker Keck, Stuttgart, DE;
Assignee:
DaimlerChrysler AG, Stuttgart, DE;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C21D / ; C23C / ;
U.S. Cl.
CPC ...
148519 ; 148226 ; 148233 ;
Abstract
A method for the production of hollow shafts from welded or seamlessly produced steel tubes having a maximum carbon content of 0.35% includes (1) carburizing a tube to a carbon content greater than 0.5%; (2) slowly cooling the carburized steel tube down from the process temperature, so that it undergoes no increase in hardness; (3) machining and/or non-cutting processing the carburized and soft steel tube to produce a workpiece blank; and (4) hardening the workpiece blank by local heating and quenching at desired points.