Patent ID: 8115796

Claim:
A beltless tandem-type image forming apparatus, comprising: a plurality of pairs of transfer rollers made up of an image carrier roller and an opposed roller which is brought into pressure contact with the image carrier roller, a plurality of the pairs of transfer rollers being placed side by side at intervals along a conveying direction of sheets on which an image should be formed; an imaging section for forming an image on surfaces of the respective image carrier rollers; a driving section for driving the respective pairs of transfer rollers so that the sheets are conveyed along the conveying direction; and a control section for independently conveying the sheets in sequence through nip sections of the respective pairs of transfer rollers driven by the driving section, while sequentially transferring images formed by the imaging section on the surfaces of the respective image carrier rollers onto the sheets, wherein conveying speeds of the respective pairs of transfer rollers controlled by the driving section are gradually decreased for every pair of transfer rollers from an upstream side toward a downstream side along the conveying direction of the sheets, and consequently, a driving period for driving the respective pairs of transfer rollers to convey each sheet is gradually increased for every pair of transfer rollers from the upstream side toward the downstream side along the conveying direction of the sheets, and wherein the control section performs control so that an imaging period by the imaging section is synchronized with a driving period by the driving section in every pair of transfer rollers.