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:
Jul. 23, 2002
Filed:
Mar. 29, 2001
Makoto Gotou, Nishinomiya, JP;
Masaaki Ochi, Hirakata, JP;
Hideaki Mori, Moriguchi, JP;
Hideki Nishino, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
FET power transistors of a power supplying part execute high-frequency switching operation and form current paths to three-phase windings. A voltage detecting part compares terminal voltages of the three-phase windings and produces a detected pulse signal in response to a comparison result. A state shifting part and an activation control part control active periods of the FET power transistors in response to the detected pulse signal. A commanding part produces a command signal in response to an output pulse signal of the voltage detecting means. A switching operation block produces a switching pulse signal in response to a comparison result of a current-detection signal with the command signal, and causes at least an FET power transistor of the power supplying part to perform high-frequency switching in response to the switching pulse signal. The state shifting part produces a timing signal after an adjust time from the detection of the detected pulse signal and shift-holds a holding state in response to the timing signal. The state shifting part changes the adjust time smaller in case that the command signal is larger than a predetermined value, thereby making the product value of the adjust time and the rotational speed smaller in the case.