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. 18, 2011
Filed:
Jan. 12, 2005
Yukitaka Hayakawa, Kuwana, JP;
Jun Hirade, Kuwana, JP;
Tetsuya Kurimura, Kuwana, JP;
NTN Corporation, Osaka-Fu, FR;
Abstract
In order to prevent degradation of accuracy and decrease of strength when a hydrodynamic bearing device is assembled and to reduce a cost of the hydrodynamic bearing device, a guide face serving as a guide when a disc hub is press fitted into a shaft member is formed on the shaft member. Then, the guide face, an outer circumferential surface of the shaft member adjacent to the guide face, and a boundary portion between the guide face and the outer circumferential surface are ground simultaneously, thereby forming a blunting portion having a radius r in the boundary portion. Thus, no edge remains between the guide face and the outer circumferential surface. Therefore, press-fitting resistance when the disc hub is press fitted to an end of the shaft member can be reduced.