| 摘要 |
PURPOSE:To enable prevention of failure in normal formation of an image in the stage of changing over developing devices by prohibiting the change in selection of the developing devices during image forming operation. CONSTITUTION:A photosensitive drum 7 is disposed in approximately the central part of a body 1. An electrifier 8 for electrification, an optical system 9, a two-color developing device 10, an electrifier 11 for transfer, an electrifier 12 for stripping, a cleaning device 13 and a destaticizing lamp 14 are successively disposed around the photosensitive drum 7. Plural pieces of the developing devices, selecting means for selecting the desired developing device among the developing devices and image forming means for forming an image on an image forming medium by using the developing device selected by the selecting means are provided. A control means for prohibiting selection of the developing device by the selecting means during the image forming operation by said image forming means is further provided. |
