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:
Mar. 05, 1996
Filed:
Jul. 13, 1994
Toshiyuki Teshigawara, Maebashi, JP;
Yoshikazu Kokubun, Gunma, JP;
Sanden Corp., Isesaki, JP;
Abstract
A method of making a cylindrical ferromagnetic body and cover assembly for a rotor of a dc motor is provided. In a first embodiment, a blend of a powdered ferromagnetic material and a heat-curable binder is compressedly molded into a cylindrical form in a generally cylindrical non-magnetic cover material having an annular flange around the top thereof, while heat is applied to the material from a heated stationary mold through the cover material, so that the cylindrically-molded ferromagnetic body firmly adheres to the cover material in the molding process. After the ferromagnetic body is cured, an non-magnetic annular protector is placed on the top of the cylindrically-molded body and the annular flange is radially inwardly bent over onto the protector. In a second embodiment, a heated block of a powdered ferromagnetic material is deposited in a cup-shaped non-magnetic cover material. The block is subsequently pressedly molded into a cup-shaped form in the cup-shaped cover material so that the molded material firmly adheres to the cover material. After the molded material is cooled, a top section and a bottom section of the cup-shaped body, together with the corresponding top section and the bottom section of the cover material, are cut off so as to obtain a cylindrical ferromagnetic body and cover assembly.