| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus constituted so that an image forming condition adjusting operation required before forming an image can be finished in a short time. SOLUTION: When adjusting an image forming condition before forming the image, a sticking toner quantity on a toner sticking pattern is detected by a P sensor, and a toner concentration control reference value Vref in a developing device is set based on the detected value. Thereafter, the output Vt of the toner concentration sensor is compared with the value Vref, and in the cast Vt<Vref is established, it is judged by the image forming apparatus that the toner concentration is excessive, then, the toner is forcibly consumed. By consuming the excessive toner in forming a pattern latent image at adjusting the surface potential of the photoreceptor, the surface potential of the photoreceptor can be controlled, and also, the toner concentration can be adjusted. Besides, the size of the pattern latent image is changed, a developing bias voltage to be applied on the latent image is changed, and also, a toner consumption pattern is formed around the latent image in accordance with the quantity of toner to be consumed. |
