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:
Dec. 27, 1988
Filed:
Mar. 16, 1987
Applicant:
Inventors:
Toshimi Abukawa, Hitachioota, JP;
Kazuo Tahara, Hitachi, JP;
Noriyoshi Takahashi, Hitachi, JP;
Toshio Tomite, Katsuta, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02K / ;
U.S. Cl.
CPC ...
310154 ; 310 46 ; 310185 ; 310258 ;
Abstract
A permanent magnet field DC machine comprises a rotor and a stator. The rotor comprises an armature core (3), an armature winding (4), and a commutator (2). The stator comprises a yoke (7), permanent magnets (8) disposed on the inner periphery of the yoke (7), and magnetic pole pieces (9) interposed between the yoke (7) and a portion of each magnetic pole (8). The magnetic pole pieces (8) are made of a material the permeability of which is greater than that of the permanent magnets.