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:
Apr. 11, 2000
Filed:
Dec. 18, 1997
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A sinusoidal wave data stream for correcting a torque ripple of a motor is stored in a torque ripple corrective memory. As the motor rotates, rotational angle information is computed from a rotational pulse signal and a rotor magnetic pole position pulse signal, which are generated accompanying the rotation. A sinusoidal wave data corresponding to the rotational angle information is recalled. Then, the sinusoidal wave data constituting a torque ripple corrective signal is subtracted from a motor control signal. With the use of the motor control signal after the subtraction, the motor is driven and controlled. With this arrangement, the motor torque ripple, which is a main cause of speed fluctuation of a polyphase brushless motor, is suppressed and stable and precise motor speed control is achieved.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile