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:
Nov. 28, 2006
Filed:
Nov. 22, 2005
Koji Harada, Kyoto, JP;
Koji Harada, Kyoto, JP;
Nidec Corporation, Kyoto, JP;
Abstract
In the invention, a PWM signal is formed at a frequency of a reference pulse signal, the PWM signal which has a pulse width being changed according to a frequency difference between an FG pulse signal for detecting a speed of a brushless motor and the reference pulse signal of a target speed, an output signal for PWM control is formed by an N-fold frequency of the PWM signal, the output signal for PWM control in which a pulse having the divided pulse width is arranged in each N-divided period, the N-divided period in which each one period of the PWM signal is divided by N, and electric power supply to a coil of each phase of the brushless motor is turned on and off at intervals shorter than that of the output signal control without increasing the frequency of the reference pulse signal. Therefore, speed control performance of the brushless motor is improved while avoiding the upsizing and const increase of the apparatus
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile