| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device maintaining accurate toner concentration, reducing the number of times of requiring the forcible replenishment control of toner, and giving pleasant service environment to a user by performing toner concentration control in accordance with developing speed, and enabling the user to easily grasp the state of the insufficient remaining amount of the toner in a toner hopper, whereby measures taken to cope with the insufficient remaining amount of the toner are accelerated. SOLUTION: This image forming device forming an image on transfer material is provided with a toner concentration detection means for intermittently detecting the toner concentration of two-component type developer and a control means controlling toner concentration detecting frequency and a toner replenishing means. The control means changes the toner concentration detecting frequency by the toner concentration detection means in accordance with the developing speed of a developing device. Then, it is also provided with a toner storing part storing the toner, a toner existing amount detection means detecting the existing amount of the toner and a control means for controlling the adhesive amount of the toner to the image carrier. The control means lowers the adhesive amount of the toner to the image carrier when the existing amount of the toner inside the toner storing part becomes equal to or under a specified value. |
