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:
May. 27, 2014
Filed:
Mar. 14, 2013
Applicant:
Nidec Corporation, Kyoto, JP;
Inventor:
Hiroyuki Abe, Kyoto, JP;
Assignee:
Nidec Corporation, Kyoto, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 19/20 (2006.01);
U.S. Cl.
CPC ...
Abstract
A spindle motor of a disk drive apparatus includes a base unit, a stator core, a covered cylindrical rotor hub, a rotor magnet, and a bearing mechanism. The height of the stator core in an axial direction is about 50% or more and about 70% or less of the height of the stator. A torque constant Kt of torque generated between a stator and a rotor magnet is about 4 mN·m/A or more and about 6 mN·m/A or less. A motor constant Km is about 2 mN·m/(A·√Ω) or more and about 4 mN·m/(A·√Ω) or less.