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:
Feb. 14, 1989
Filed:
Jun. 03, 1987
Yukihiko Machida, Tokyo, JP;
Tadafusa Tomitaka, Tokyo, JP;
Sony Corporation, , JP;
Abstract
A motor rotation control apparatus employs a comb filter circuit operable to filter out a signal component and its higher harmonics. An error signal indicative of an error between actual and target conditions of rotation of the motor is applied to the comb filter circuit after its DC component is removed. The filtered signal and the error signal are added in a circuit which produces a control signal used to control the motor rotation. In another aspect of the invention, the error signal is divided into a first digital signal having upper bits of data having a predetermined bit number and a second digital signal having the remaining lower bits of data. The lower bits of data are delayed a predetermined time and added to the error signal to compensate for lower bits of data which may be ignored in a digital-to-analog converter operable, with a limited bit number, to provide a control analog signal used to control the motor rotation.