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:
Jan. 22, 1985
Filed:
Dec. 16, 1983
Hisashi Tokizaki, Gunma, JP;
Hironobu Sato, Gunma, JP;
Sanyo Electric Co., Ltd., both of, JP;
Tokyo Sanyo Electric Co., Ltd., both of, JP;
Abstract
A control device for brushless motor comprises an inverter (3), a control circuit (8) and a rotor position detecting circuit (9). In the rotor position detecting circuit (9), voltage induced in stator coils (U, V and W) due to rotation of a rotor (7) and neutral voltage at a virtual neutral point (25) are compared by comparators (CU, CV and CW) so that polarity changing points can be detected. The control circuit (8) controls the inverter (3) based on the above stated polarity changing points so as to control changeover of the modes for conducting to the stator coils (U, V and W). As a result, rotation of a brushless motor can be controlled without using Hall elements.