| 摘要 |
PURPOSE:To prevent a developer from adhesion to a developing roller at the time of non-development by optionally lifting a bottom plate of a developer container opposed to a developer feeding part positioned on the upper side than a doctor blade in a developing roller rotating direction. CONSTITUTION:To drive a copying machine, the bottom plate 16 of a developer container 2 storing a developer of color to be used for development is set up to the ascending the position and the bottom plate 16 of the other developer container 2 is set up to the descending position. Consequently, the developer of color which is not used for development is receded in a recessed part 18 formed by descending the bottom plate 16 of the developer container 2 and separated far from a developer feeding part 13 of the developing roller 4. Thereby, the developer sucking force of the developing roller 4 is not applied to the developer and a magnetic brush is not formed on the periphey of the developing roller 4, so that picture quality can be prevented from deterioration due to the adhesion of developer of a color which is not used for development to surface of a photosensitive drum 3. |
