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:
Oct. 06, 1987
Filed:
Jun. 05, 1986
Makoto Yoshida, Machida, JP;
Aupac Co., Ltd., Tokyo, JP;
Abstract
A dc brushless electromagnetic rotary machine, such as a dc electric motor or a dc electrical generator, includes a rotor having a permanent magnet which has the entirety of its cylindrical outer peripheral surface magnetized in the same polarity. The outer surface faces an annular armature core fixed on the inner cylindrical surface of a casing frame forming a stator of the machine. In the structure, the magnetic flux emanating from the rotor magnet passes the armature core and returns to the magnet from a position other than the armature core. The armature core is provided with coil windings on its cylindrical inner surface facing substantially the one surface portion of the permanent magnet. A portion of the coil windings is covered with a shielding member in which portion current is conducted which induces magnetic flux in a direction opposite to that of the magnetic flux generated from the permanent magnet. Additional magnetic flux induced in response to current flowing over the armature windings causes the main magnetic flux generated from the rotor magnet to be turned in the same way irrespective of the angular position of the rotor. Consequently, the current which is conducted in the armature windings to induce the magnetic flux in the direction opposite to that of the main magnetic flux does not prevent the torque for continuously rotating the rotor from being decreased.