To press a developing roller against a photoreceptor drum with a uniform pressing force.
An image forming apparatus has a plurality of photoreceptor drums 2a, 3a, 4a, and 5a which are arranged so that their center axes of rotation are parallel to one another, developing rollers 2b, 3b, 4b, and 5b which supply toner to electrostatic latent images formed on the photoreceptor drums 2a, 3a, 4a, and 5a to visualize them, guide grooves 22 which are formed extending toward the centers of rotation of the photoreceptor drums 2a, 3a, 4a, and 5a and in which rotary shafts 23 projecting from both width-directional ends of the developing rollers 2b, 3b, 4b, and 5b are fitted, and torsion springs 24 which are fitted to be pressed against the rotary shafts 23 of the developing rollers 2b, 3b, 4b, and 5b and press the developing rollers 2b, 3b, 4b, and 5b against the photoreceptor drums 2a, 3a, 4a, and 5a.
TASAKA KOICHI
Tomoyasu Sakaguchi
Hiroki Naito