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. 02, 2004
Filed:
Feb. 24, 2003
Masahiro Yasohara, Hyogo, JP;
Kenji Sugiura, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In a motor driver, based on driving waveforms of respective phases generated by a driving waveform generator, a power feeder feeds respective phase-coils with an alternating current consecutively changing in sine wave. Further, a phase advancing controller adjusts phases of the driving waveform, and performs phase-advancing control such that each phase of back electromotive forces induced in respective phase-coils generally coincides with a phase of the ac running through the coils. In phase-advancing controlling, a phase current is detected with a common current. The structure discussed above can reduce torque ripples, vibrations and noises, and a motor thus can be driven efficiently.