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. 30, 2004
Filed:
Mar. 27, 2002
Shoji Maruyama, Shizuoka-ken, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention provides a servo-control apparatus for a motor, comprising position detecting means for detecting a rotational position of a motor, rotational speed signal generating means for generating a rotational speed signal corresponding to a rotational speed of a motor, and digital control means for generating an exciting electric current to be supplied to a coil of the motor as a PWM signal in accordance with the rotational speed signal from the rotational speed signal generating means, and wherein a switching signal for switching the exciting electric current to be supplied to the coil of the motor is formed by a pre-driver in accordance with the position detection signal from the position detecting means, and the pre-driver combines the switching signal with the PWM signal from the digital control means to generate an electric current control signal by which the motor is driven, thereby coping with the speed change of the motor quickly and stably.