Patent ID: 6307578
Filing Date: 2001-10-23
Classification: G03G

Abstract:
A color printer having imaging stations disposed along a photoreceptor belt for producing images on said belt, said belt passing around an idler roll, wherein one or more of said imaging stations is disposed on a right span of said belt extending from a right side of said idler roll and a plurality of said imaging stations is disposed on a left span of said belt extending from a left side of said idler roll, each of said imaging stations including a charger, an imager, and a developer, said printer including a belt driver which drives said photoreceptor belt around said idler roll and past said imaging stations, and wherein said printer also includes a system for compensating for eccentricity in said idler roll to preserve registration among the images of said imaging stations, wherein an eccentricity of said idler roll induces different cyclic disturbances in said right and sold left spans, said system comprising:a sensor for sensing an index of said idler roll; anda corrector responsive to a position of said index for outputting an eccentricity correction function altering the location on said belt of the image of one of said imaging stations on said right span relative to the images of said plural imaging stations on said left span to compensate for said eccentricity, the correction function being applied to said belt driver and being operative to alter a speed of said belt to compensate for a differential speed between said right span and said left span of the belt, thereby to accomplish said altering of the location of the image of said one imaging station.