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:
Sep. 08, 1998
Filed:
Oct. 17, 1996
Kazuhiko Yoshida, Iwata, JP;
Tatsuhiro Goto, Iwata, JP;
Akira Wakita, Iwata, JP;
Toshio Kawasaki, Kobe, JP;
Toyofumi Hasegawa, Kobe, JP;
Hideo Takeshita, Kobe, JP;
Toshiki Suwa, Kobe, JP;
NTN Corporation, Iwata, JP;
Abstract
The present invention provides an outer ring for a high strength constant velocity joint which has an excellent torsional strength and torsional fatigue strength and can provide an improved processability, and a process for producing the same. An outer ring used for a high strength constant velocity joint having an involute serration part and a screw part, the outer ring made of a steel containing: C: 0.45 to 0.53%, Si: 0.05 to 0.25%, Mn: 0.7 to 1.0%, Al: 0.01 to 0.05%, Mo: 0.2 to 0.4%, N: 0.003 to 0.012%, the remainder being Fe and inevitable impurities, the inevitable impurities including: Cr: 0.05% or less than 0.05%, P: 0.015% or less than 0.015%, S: 0.01% or less than 0.01%, and O: 0.002% or less than 0.002%, wherein an old austenite crystal grain at the involute serration end is 8 or more in JIS grain size classification; a surface hardness at the end is 720 or more in Hv; and a ratio (CD/R) is 0.35 to 0.60 where CD is an effective hardened layer depth at which a hardness at the end is 450 in Hv and R is a radius of a shaft part.