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. 13, 1994
Filed:
Sep. 17, 1993
Tadao Yamaguchi, Isesaki, JP;
Naohisa Koyanagi, Isesaki, JP;
Tokyo Parts Industrial Co., Ltd., Isesaki, JP;
Abstract
A dc brushless vibrator motor employs a cylindrical coreless stator winding unit having at least three stator coils arranged at about an even pitch angle and a rotor that includes an axially extended eccentrically-weighted permanent field magnet that is magnetized so as to have alternate north and south poles about the rotational axis of the rotor. A cross-section of the field magnet in a plane perpendicular to the rotational axis has generally an arcuate or sectorial shape which is within an angular range of 180.degree. to 270.degree. about the rotational axis. The center of mass of the rotor, therefore, is off the rotational axis, thereby causing vibrations.