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:
Jul. 02, 1996
Filed:
Jul. 19, 1993
Mikio Nakasugi, Chofu, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A scanning motor includes a fixed shaft made of a ceramic material. The rotary sleeve is rotatably fitted onto the material, and a rotary sleeve also made of a ceramic fixed shaft so as to be rotatable about the fixed shaft. The motor further includes a thrust plate fixed to one end portion of the rotary sleeve. At least an abutting surface of the thrust plate faces an end surface of the fixed shaft. The motor further includes a driver for rotating the fixed sleeve. At least one of the end surface of the fixed shaft and the abutting surface of the thrust plate has the shape of at least a part of the surface of a sphere. A fixing member, made of a metal material, can be fixed around the rotary sleeve and a rotary polygonal mirror and a driving magnet can be fixed to the fixing member. During high speed rotation, the rotary sleeve is supported by the fixed shaft under a non-contact condition in the radial direction due to a film of air produced on the fitting surface therebetween, and under a point-contact condition in the thrust direction. As a result, power consumption is small even when the rotating polygonal mirror is rotated at a high speed and the biting phenomenon due to the invasion of dust and vibration is hardly present. Thus, precision high speed rotation can be maintained.