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. 03, 1999
Filed:
Jan. 14, 1998
Applicant:
Inventors:
Assignees:
Hitachi Powdered Metals Co., Ltd, Chiba, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02K / ;
U.S. Cl.
CPC ...
310 905 ; 310 90 ; 310 905 ; 384100 ; 384291 ; 384279 ;
Abstract
An improved porous bearing and a motor which is provided with the porous bearing in which the friction losses and reflection of shaft are reduced, noises caused by the vibrations are avoided with low cogging or low jitter, and in addition, the manufacturing process is simplified to obtain long-life products at low cost. The number (C) of grooves of the porous bearing meets at least one of the following equations: