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:
Apr. 23, 2002
Filed:
Apr. 20, 2000
Ichiro Maekawa, Kawasaki, JP;
Kazutaka Takeuchi, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A shaft integral with a rotary polygon mirror is fitted in a sleeve so as to be rotatable, and the bearing clearance is filled with a lubricant. The lubricant comprises a base oil comprising a mixed oil consisting of a plurality of components whose vapor pressures are equal or close to each other. Suitably combining components of different viscosities makes it possible to prepare the lubricant so as to have such a viscosity to match with the bearing characteristics. Selection of components having a little difference in vapor pressure prevents viscosity change due to volatilization of a specific component. Thus, the viscosity change of the lubricant in the bearing clearance is prevented.