| 摘要 |
PURPOSE:To prevent the deterioration of a developer by setting a rotary speed of the stirring blade to an optimum high speed value by which rise of electric charge of a developer becomes quick for a prescribed time, in case of a copying mode, and changing it to a low speed in which fatigue of the developer is not accelerated in other time. CONSTITUTION:In case of a copying mode, a developer 9 circulates in the equipment by rotating of a scooping roller and two development rollers 3a, 3b, it contacts like a brush with an electrostatic latent image carried on the sensitive body drum as a part to be developed, through the drum 1, and forms an image. And, as soon as the scooping roller 2 starts its rotation at time t1, the stirring blades 4a, 4b start the rotation at a low speed, and replenishment of the developer is started at time t2 and the rotation of the stirring blades 4a, 4b is changed to a high speed. When copying has been finished, said rotary speed is changed to a low speed at time t4, and the rotation is stopped at t5. Since said operation is performed, fatigue of a developer is reduced without deteriorating the efficiency of the stirring blade. |
