Abstract: In a multicolor image forming apparatus, in order to form two pages of toner images on a transfer belt, a plurality of images are written during a first interimage period. After writing of the plurality of images, a development unit is rotated during a subsequent second interimage period to prepare for the subsequent toner color. The second interimage period is predetermined longer than the first interimage period. The second interimage is predetermined including the time required until the development of the images thus written is terminated, the time required for the rotation of the development unit and the time required for convergence of vibration caused accompanying the rotation.

Abstract: In a multicolor image forming apparatus, an intermediate transfer belt is moved at a first speed. A secondary transfer roll is pressed against the intermediate transfer belt at the time of secondary transfer in order to secondarily transfer a multicolor toner image on the intermediate transfer belt onto recording paper. The secondary transfer roll is rotated by a driving unit including a gear unit at a peripheral speed higher than the first speed. A torque limiter limits the driving torque of the secondary transfer roll pressed against the intermediate transfer belt to the load torque of the secondary transfer roll separated from the intermediate transfer belt. Consequently, the secondary transfer roll is rotated at a speed equal to or slightly higher than the speed of the intermediate transfer belt and the load of the secondary transfer roll applied to the intermediate transfer belt never exceeds a predetermined value.