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:
Oct. 15, 2013
Filed:
Jan. 05, 2012
Tokuji Tsunematsu, Gifu, JP;
Kazushige Nakajima, Gifu, JP;
Hiroyuki Kitazwa, Gifu, JP;
Tomoyuki Yokogawa, Gifu, JP;
Tokuji Tsunematsu, Gifu, JP;
Kazushige Nakajima, Gifu, JP;
Hiroyuki Kitazwa, Gifu, JP;
Tomoyuki Yokogawa, Gifu, JP;
Nabtesco Corporation, Tokyo, JP;
Abstract
The command signal processing unit outputs, when a first PWM frequency command signal is received, a high-PWM frequency command signal such that an asynchronous PWM control is performed at a PWM frequency of a predetermined constant frequency. The command signal processing unit outputs, when a second PWM frequency command signal is received, a low-PWM frequency command signal such that an asynchronous or synchronous PWM control is performed at a frequency lower than the above-described frequency. The PWM frequency control unit controls the PWM frequency such that an asynchronous PWM control is performed if a motor has a rotational speed less than a predetermined rotational speed and that a synchronous PWM control is performed if the motor has a rotational speed greater than or equal to the predetermined rotational speed, when a low-PWM frequency command signal is input.