| 摘要 |
PURPOSE:To completely prevent the occurrence of color mixture without making the developer complicated and causing the vibration and noise by rotating a developing sleeve for a developing device at non-developing time in a direction opposite to the rotation of the developer sleeve at a developing time and retreating the developer and constituting the device so that the switching of a developing state and a non- developing state may be executed, as for a multicolor image forming device. CONSTITUTION:When the developing device 7 is in a developing state, the developing sleeve 102 is rotated in a direction shown by an arrow (c), the developer 70 is supplied to the developing sleeve 102 by a developer supply pole S2, and the layer thickness of the developer is made constant by a developer napping height control plate 74 in accordance with a rotating direction, and then, the developer is carried into a developing area X. When the developer 7 is not in developing, the developing sleeve 102 is rotated in a direction shown by an arrow(e), that is, a direction opposite to the rotation of the sleeve 102 at the developing time. A magnetic force attracting the developer 70 stored in a mixture part is not imparted to the magnetic pole S3 in the developing sleeve 102, then, the sleeve is rotated without the developer sticking, the part comes out in the developing area X. Thus, the developer 70 on the developing sleeve 102 is instantaneously cleared away. |
