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. 13, 2004
Filed:
Oct. 20, 2000
Junji Sato, Tokorozawa, JP;
Eikichi Sashida, Tanashi, JP;
Hideharu Miyauchi, Tanashi, JP;
Yousuke Sakakibara, Tokorozawa, JP;
Hiroshi Ikeda, Tokorozawa, JP;
Eigo Hashimoto, Tokorozawa, JP;
Citizen Watch Co., Ltd., Tokyo, JP;
Abstract
A rotor ( ) for a miniature electric motor includes a magnet ( ) having a rotation axis ( ) and a shaft ( ) fixed concentrically to the magnet. The magnet ( ) includes a through hole ( ) extending coaxially with the rotation axis ( ). The shaft ( ) includes a portion ( ) fitted in the through hole ( ). The portion ( ) has an axial interengagement length (t ) shorter than an axial length (T ) of the through hole ( ). The rotor ( ) also includes reinforcing means provided at least inside the through hole ( ). The magnet ( ) comprises an annular magnet material ( ), and a coating ( ) formed on a surface of the magnet material and arranged at least inside the through hole ( ). The reinforcing means is formed as the coating ( ) of the magnet ( ), and acts to ensure a fixing force to securely hold the shaft ( ) in a predetermined position on the magnet.