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:
Mar. 01, 2005
Filed:
Mar. 14, 2003
Kazushige Morita, Nara, JP;
Yuriko Shindoh, Yamatokoriyama, JP;
Hiroko Ishibashi, Ikoma, JP;
Yoshihide Shimoda, Nara, JP;
Masanori Matsumoto, Kashihara, JP;
Kazushige Morita, Nara, JP;
Yuriko Shindoh, Yamatokoriyama, JP;
Hiroko Ishibashi, Ikoma, JP;
Yoshihide Shimoda, Nara, JP;
Masanori Matsumoto, Kashihara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
An electrophotographic color image forming apparatus including a multiple number of photoreceptors for multiple development colors including black, is constructed such that the photoreceptors satisfy the following relation:0.5<()<0.8,where X represents the reduction in film thickness (Å) per 1×10mm of the traveling distance of the photoreceptor for black development and Y represents the reduction in film thickness (Å) per 1×10mm of the traveling distance of the photoreceptors for the other development colors. This limitation is aimed at differentiating the abrasion resistance of the photoreceptors between that for black and that for colors and designating the reduced amounts of the film thickness per unit traveling distance to fall within the predetermined ranges, whereby it is possible to prevent the drum for black development, which is used most frequently, alone, from being worn away at an earlier time. Accordingly, both the drums for black and for colors can be replaced at approximately the same time, to the maintenance cost can be reduced.