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:
Feb. 20, 1996
Filed:
Sep. 16, 1993
Nobuaki Nakamura, Fujieda, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
A brushless motor of the present invention generally has a stator and a rotor in a clean chamber of contaminant free atmosphere. The stator has a motor base, a shaft provided on the motor base and a plurality of coils on the motor base. The rotor has a bearing holder having a center hole for supporting bearings, a hub connected to the bearing holder for mounting information storage discs such as hard discs and a magnet having magnetic poles provided on the hub facing to the coils. The brushless motor of the present invention further has a top cover provided on the bearing holder for covering the center hole thereof, a cylindrical chamber defined by an outer wall of the bearing holder and an inner wall of the hub in the rotor, the magnet is provided on the inner wall of the bearing holder, and a coreless coil assembly having the plurality of coils without cores made of magnet materials being provided on the motor base in such a manner that the coreless coil assembly protrudes into the cylindrical chamber so as to form narrow clearances between the walls of the cylindrical chamber and the coreless coil assembly for a labyrinth path in the clean chamber.