Patent ID: 6938351

Claim:
An image forming device comprising: a plurality of photoreceptor drums on which a latent image is formed on a cylindrical peripheral surface by a difference in electrostatic potential and on which toner images of different color are respectively formed due to deposition of toner; an endless belt looped between two support rollers to be in contact with any one of the plurality of photoreceptor drums wherein the toner images on the photoreceptor drums are superimposed to be transferred onto an outer peripheral surface or a recording sheet carried on the outer peripheral surface; and transfer rollers that are in pressed contact with the respective photoreceptor drums from an inner side of the endless belt; wherein the plurality of photoreceptor drums include one having a different diameter from one another, the transfer rollers are made of an identical material and have an identical diameter, each of the transfer rollers is in pressed contact with each of the photoreceptor drums at a downstream side with respect to a moving direction of the endless belt from a position (hereinafter referred to as a contact reference position) of the peripheral surface of the photoreceptor drum where a radius of the photoreceptor drum is approximately perpendicular to a direction that the endless belt is looped, and a distance from the contact reference position to a pressed position of the transfer roller of a large-diameter photoreceptor drum is set greater than that of a small-diameter photoreceptor drum.