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. 20, 2001
Filed:
Jan. 28, 2000
Applicant:
Inventors:
Kazuhiko Yoshida, Shizuoka-ken, JP;
Hiroaki Makino, Shizuoka-ken, JP;
Akira Wakita, Shizuoka-ken, JP;
Assignee:
NTN Corporation, Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
C22C 3/802 ; C22C 3/804 ; C22C 3/806 ; C21D 9/28 ; C21D 9/30 ;
U.S. Cl.
CPC ...
C22C 3/802 ; C22C 3/804 ; C22C 3/806 ; C21D 9/28 ; C21D 9/30 ;
Abstract
The power transmission shaft,is made by applying induction hardening to carbon steel with hardening ratio in a range from 0.25 to 0.50. For the carbon steel, one containing 0.39 to 0.49% of C, 0.4 to 1.5% of Si, 0.4 to 1.0% of Mn, 0.025% or less S, 0.02% or less P and 0.01 to 0.1% of Al by weight as the basic components, with the rest comprising Fe and inevitable impurities is used. This makes it possible to achieve higher strength and lighter weight of the power transmission shaft.