Electrostatic copying machine comprising improved magnetic brush developing-cleaning unit

摘要: A magnetic brush is used to develop a toner image on photoconductive drum and subsequently remove residual substance from the drum. An electrode roller disposed closely adjacent between developing tank containing in direction of rotation brush. For cleaning drum, an electric potential applied which causes be transferred roller, thereby reducing amount improving effect. development, may reversed transfer back increase theamount thereon. Alternatively, removed for recycling no effected during development. As yet another alternative, varied development accordance with sensed density suitable adjust printing desired value.