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:
Oct. 07, 2008
Filed:
Jun. 30, 2005
Yoshio Kanzaki, Tokyo, JP;
Yoshio Kanzaki, Tokyo, JP;
Ricoh Company Limited, Tokyo, JP;
Abstract
A color image forming apparatus including tandem type image forming units that form images of different colors, respectively. The image forming units form test marks of different colors on a conveyor belt in its conveying direction at predetermined intervals. The test marks include linear position displacement detecting test marks and density detecting test marks. Each of the linear position displacement detecting test marks extends in a direction perpendicular to the conveying direction of the conveyor belt, and each of the density detecting test marks includes an area having a predetermined density and being adjacent to each of the linear position displacement detecting test marks. A detection operation for detecting position displacements of the linear position displacement detecting test marks in a sub-scanning direction of the conveyor belt and a detection operation for detecting densities of the density detecting test marks are performed, based on detection signals output from sensors.