Patent ID: 6470166
Filing Date: 2002-10-22
Classification: G03G

Abstract:
A color-image forming apparatus comprising:an exposure unit; plural image-forming units arranged in a tandem manner and having different color toners therein, respectively, each of said image-forming units including a photosensitive drum on which an electrostatic latent image is formed by the exposure unit, and a developing unit for forming a toner image by applying toner onto the latent image; and an endless inter-stage transfer belt for transferring plural toner images of different colors formed on said drums by overlapping one after another while traveling an endless path looped over plural rollers along a direction of an arrangement of the image-forming units; wherein the inter-stage transfer belt comes into contact with the photosensitive drums only while accepting the toner image formed on the photosensitive drums; wherein both of engaging and disengaging motions between the inter-stage transfer belt and the photosensitive drums are performed while the belt and the drums are both in operation; and wherein a belt-drive unit for running the inter-stage transfer belt and a drum-drive unit for rotating the photosensitive drums that carry the plural images of different colors are independently structured, and the belt-drive unit and the drum-drive unit are to be driven in order with time-shifted starts.