IMAGE FORMING APPARATUS Russian patent published in 2013 - IPC G03G15/00 

FIELD: physics.

SUBSTANCE: image forming apparatus has a drum, a developing device having an element which carries the developer which contains nonmagnetic toner and a magnetic carrier, and for moving the developer into a developing position, wherein the element which carries the developer lies opposite the drum; a detecting part for detecting information which correlates with the amount of toner charge of the developer in the developing device; and a controller which can operate in a mode during the image formation period, wherein an image is continuously formed on multiple recording materials, drive of the element which carries the developer, in a first period in which a region of the drum in which no image is formed, which corresponds to the inner space between the recording material and the next recording material, passes through the developing position, stops or reduces its speed below the speed in the second period, in which a region of the image which corresponds to the recording material passes through the developing position. Based on the detection result of the detection means, the controller controls the developing device so that when the amount of toner charge drops, the toner is less susceptible to deposition on the element which carries the developer in the first period than in the second period during operation in that mode.

EFFECT: design of an image forming apparatus which is capable of eliminating an image defect independent of the condition of use of the developer, ensuring stability of image quality, wear-resistance of the image forming apparatus.

9 cl, 27 dwg