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:
Jan. 02, 2018
Filed:
Oct. 01, 2010
Kazuhiko Yoshida, Shizuoka, JP;
Hiroki Mukai, Shizuoka, JP;
Hirokazu Ooba, Shizuoka, JP;
NTN CORPORATION, Osaka, JP;
Abstract
A hollow shaft, which is usable with a constant velocity universal joint, has an increased static torsional strength and torsional fatigue strength of a small diameter portion (small diameter portion having a smooth outer peripheral surface) formed near a spline at an end portion of the hollow shaft, and has a reduced manufacturing cost. The hollow shaft is molded by plastic working from a tubular blank, and subjected to quench hardening treatment. The quench hardening treatment includes carburizing and quenching treatment. The hollow shaft includes a softened section formed in a part of the hollow shaft by local heating treatment after carrying out the carburizing and quenching treatment.