Patent ID: 6920302

Claim:
An image forming apparatus comprising: a first image carrying body that carries a first electrostatic latent image; a first developing device that develops the first electrostatic latent image formed on the first image carrying body into a first toner image, and removes excess toner on the first image carrying body; a second image carrying body that carries a second electrostatic latent image; a second developing device that develops the second electrostatic latent image formed on the second image carrying body into a second toner image, and removes excess toner on the second image carrying body; a third image carrying body that carries a third electrostatic latent image; and a third developing device that develops the third electrostatic latent image formed on the third image carrying body into a third toner image, and removes excess toner on the third image carrying body; a fourth image carrying body that carries a fourth electrostatic latent image; a fourth developing device that develops the fourth electrostatic latent image formed on the fourth image carrying body into a fourth toner image, and removes excess toner on the fourth image carrying body; a controlling means which controls a discharge operation for the first toner mixed in the second developing device, in accordance with an integrated area developed by the first developing device and an integrated area developed by the second developing device, controls a discharge operation for the first and second toners mixed in the third developing device, in accordance with an integrated area developed by the first developing device, an integrated area developed by the second developing device and an integrated area developed by the third developing device, and controls a discharge operation for the first, second and third toners mixed in the fourth developing device, in accordance with an integrated area developed by the first developing device, an integrated area developed by the second developing device, an integrated area developed by the third developing device and an integrated area developed by the fourth developing device.