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. 26, 2006
Filed:
May. 18, 2004
Katsuhiro Sakurai, Shizuoka, JP;
Tohru Nakagawa, Shizuoka, JP;
Kisao Yamazaki, Shizuoka, JP;
NTN Corporation, Osaka, JP;
Abstract
An integral hollow type power transmission shaft is proposed which is superior in the balance between the static strength and the fatigue strength. The integral hollow type shaft is induction-hardened from the outer periphery to form a hardened layer, leaving an unhardened layer at spline portions, so that at the spline portions, the hardness on the inner surface will be lower than at other portions. This increases the toughness and compressive residual stress of the shaft at the spline portions, which tend to be starting points of fatigue cracks, thus improving the balance between the static strength and the fatigue strength.