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:
Jun. 30, 2015
Filed:
Sep. 11, 2012
Toshikazu Tsuchiya, Susono, JP;
Toshikazu Tsuchiya, Susono, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
A CPU determines that a motor is undergoing a forward rotation when a time difference between a detection timing of a light beam deflected by a rotating polygonal mirror and an output timing of a detection signal from a magnetic detector element falls within a predetermined range, and that the motor is undergoing a reverse rotation when the time difference does not fall within the predetermined range. With this configuration, a detection circuit for detecting voltage induced in three phases is unnecessary, and therefore the cost can be reduced. Furthermore, there is no need to detect voltage induced in each of the three phases. As it suffices to simply detect the time difference, the amount of time required to detect a rotation direction can be reduced.