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:
May. 21, 2002
Filed:
Dec. 21, 1999
Applicant:
Inventors:
Kazuhiko Yoshida, Shizuoka-ken, JP;
Akira Wakita, Shizuoka-ken, JP;
Hiroaki Makino, Shizuoka-ken, JP;
Hideki Kondou, Shizuoka-ken, JP;
Assignee:
NTN Corporation, Osaka, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F16D 3/26 ;
U.S. Cl.
CPC ...
F16D 3/26 ;
Abstract
A power transmission shaft using the constant velocity joint is manufactured by applying induction hardening to graphite steel thereby to harden the surface layer and form a 2-phase structure of ferrite and martensite in the core thereof. The graphite steel contains 0.35 to 0.70% of C, 0.4 to 2.0% of Si, 0.3 to 1.5% of Mn, 0.025% or less S, 0.02% or less P, 0.01 to 0.1% of Al, 0.001 to 0.004% of B and 0.002 to 0.008% of N by weight as the basic components, with the rest comprising Fe and inevitable impurities.