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:
Dec. 05, 2006
Filed:
Oct. 15, 2004
Norio Fujii, Kyoto, JP;
Toshiya Suzuki, Kyoto, JP;
Norio Fujii, Kyoto, JP;
Toshiya Suzuki, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
A rotor of a sensor-less motor has a multiplicity of magnetic poles, with one magnetic pole giving a smaller magnetic flux than other the magnetic poles. A coil is provided at a predetermined position external to the rotor. An induction signal is generated in the coil as the magnetic flux through it is changed by the rotation of the rotor. An index signal indicative of the reference rotational position of the rotor is generated based on the change in the induction signal. Thus, the reference rotational position of the disk of an information recording-reproducing unit, for example, can be detected without utilizing any Hall elements.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile