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:
Jan. 09, 2001
Filed:
Apr. 13, 1999
Toyoshige Sasaki, Yokohama, JP;
Chikara Aoshima, Zama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A rotor magnet includes a first polarized layer alternately polarized into different poles while being circumferentially divided into n parts, and a second polarized layer alternately polarized into different poles. An advance phase angle as &thgr;1 with respect to the first polarized layer is set and the magnet is circumferentially divided into n parts. First and second coils are disposed in an axial direction of the rotor magnet. A first outer magnetic pole and a first inner magnetic pole, which are a first stator excited by the first coil, are opposed to an outer peripheral surface and an inner peripheral surface of the rotor, and a second outer magnetic pole, and a second inner magnetic pole which are a second stator excited by the second coil, are opposed to an outer peripheral surface and an inner peripheral surface of the rotor. When a lag phase angle of the second stator with respect to the first stator is set to &thgr;2, the first and second polarized layers and the first and second stators are positioned so that &thgr;1 +&thgr;2 are larger than 180/n degrees. As a result, the power output of the motor is enhanced.