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:
Jan. 20, 2004
Filed:
Sep. 03, 2002
Katsutoshi Nii, Hitachi, JP;
Masaru Muranishi, Odawara, JP;
Shozo Saegusa, Ibaraki-ken, JP;
Tsuyoshi Takahashi, Odawara, JP;
Kenji Tomida, Odawara, JP;
Takashi Matsuki, Odawara, JP;
Yuuichi Yanagase, Ibaraki-ken, JP;
Mitsuyuki Tsuyuki, Kanagawa-ken, JP;
Shinobu Yoshida, Tsuchiura, JP;
Hiroshi Nishida, Kanagawa-ken, JP;
Kazuhiko Kawakami, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A spindle motor used in a magnetic disc apparatus having a hub to which a magnetic disc is mounted and a rotary shaft to which the hub is fixed. The rotary shaft is located in a bearing casing having one end opened and the other end closed by a hydrodynamic pressure radial bearing, the rotary shaft being supported by a hydrodynamic pressure thrust bearing and the hydrodynamic pressure radial bearing. An inner diameter D and a width L of the hydrodynamic pressure radial bearing having a relationship of L/D<1.