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, 2002
Filed:
Jun. 19, 2001
Yukio Itami, Yokohama, JP;
Mitsuo Suzuki, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An image forming apparatus with a DC brushless motor including a permanent magnet having n magnetized poles, where n is an even number, a rotatably held rotor on which the permanent magnet is fixed, a stator core having T-shaped pole shoes corresponding to the magnetic poles of the permanent magnet, windings fixed on the stator core and including a plurality of phases for selectively generating magnetic polarities in sequence, a driver circuit for switching conduction to the windings, and a rotating position detector for detecting a rotating position of the permanent magnet. The windings are divided into a plurality of winding groups for generating magnetic polarities in a plurality of the windings so as to produce a magnetic repellent force or a magnetic attractive force between all the magnetic poles of the permanent magnet and T-shaped pole shoes of the stator core associated with selected phases by the driver circuit based on a rotating position detected by the rotating position detector.