Patent ID: 8055161

Claim:
An image forming apparatus comprising: a photosensitive body on which an electrostatic latent image is formed; a light scanning unit which scans a beam onto the photosensitive body; a developing unit which includes a housing having an agitating space and a supply space to communicate with each other through two gates formed between the agitating space and the supply space to circulate a developer, an agitating auger rotatably mounted in the agitating space to transfer the developer, a supply auger rotatably mounted in the supply space to transfer the developer, and a magnetic roller which receives the developer by the supply auger and attaches the developer to the photosensitive body; a rotation control unit which controls rotation of the agitating auger and the supply auger; and a transfer unit which transfers a visible image formed on the photosensitive body onto a printing medium, wherein when the developer is concentrated in one of two gates, the rotation unit controls one of the agitating auger and the supply auger, which is positioned on a downstream side of the gate in which the developer is concentrated, to temporarily stop rotating, and the developer concentrated in the gate is transferred from the gate by the other one of the agitating auger and the supply auger, which is positioned on an upstream side of the gate in which the developer is concentrated.