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. 20, 1984
Filed:
Oct. 14, 1981
Tsunehiro Maruo, Yokohama, JP;
Masaomi Inagaki, Yachiyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
Apparatus for generating a signal corresponding to a reference phase of a reference rotor of a motor relative to the stator, includes a field magnet having a plurality of north and south poles mounted on the rotor; a Hall-effect element associated with the field magnet and mounted on the stator for generating a position signal corresponding to the position of the rotor relative to the stator for use in changing-over energization of coils on the stator; a plurality of equally spaced cut-out portions along the periphery of the rotor forming a plurality of equally spaced toothed portions; an optical detector associated with the toothed portions and mounted on the stator for generating a speed signal corresponding to the rotational speed of the rotor relative to the stator; a differentiating circuit for differentiating the position signal to produce a differentiated signal; and an AND gate supplied with the differentiated signal and the speed signal for producing the phase signal corresponding to a reference phase of the rotor relative to the stator.