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:
Aug. 02, 1994
Filed:
Aug. 28, 1992
Masahiro Ohsawa, Machida, JP;
Fuji Electric Co., Ltd., , JP;
Abstract
The invention provides a spindle motor for magnetic disk devices capable of coping with small magnetic disks, in which the leaking magnetic flux in the motor section does not adversely affect the magnetic head. The spindle motor consists of a stator, a magnetic disk mounting hub axially supported on a frame of the stator, a bowl-like rotor yoke protruding from the base of the hub in the radial direction and covering the top and circumference of the stator, and a rotor magnet fitted over the inner circumference of the rotor yoke in a position opposite to the magnetic pole of the stator. A clearance space comprising is provided between a mounting seat of the magnetic disk and the top of the rotor yoke. The outer diameter of the hub base is also smaller than the information-recording region of the magnetic disk, and the rotor yoke is fitted as a magnetic body on the hub, which is made from the same material as the substrate of the magnetic disk.