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:
Oct. 30, 2012
Filed:
Aug. 20, 2007
Yoshimasa Ushioda, Iwata, JP;
Hiroki Ooe, Iwata, JP;
Kazuhiro Muramatsu, Iwata, JP;
NTN Corporation, Osaka, JP;
Abstract
A steel ball rolling configuration and a constant velocity universal joint have a superior oil retention effect between a surface of a steel ball and a partner rolling surface, and can form a thick oil film, improve lubrication, and extend life of the steel ball. The constant velocity universal joint includes a rolling surface and a steel ball that is lubricated by grease and rolls over the rolling surface. A surface roughness of the steel ball is roughened to become more similar to a surface roughness of a partner rolling surface. Numerous miniscule recesses roughly tens of micrometers in size are randomly disposed on the surface of the steel ball.