developer subsequent to the transfer step the magnetic toner which attaches to the surface of the photosensitive member is removed therefrom by a cylindrical brush then transferred to a non magnetic sleeve which internally houses a magnet and finally scraped therefrom by a separator to fall down into a tray application_number US 70761576 A description referring to fig1 there is shown a photosensitive member in the form of a drum 11 having a photosensitive insulating layer on its surface and which is mounted on a shaft 12 for rotation in the direction indicated by an arrow at a uniform rate initially the drum surface is uniformly charged by a primary charger formed by a corona discharger 13 and then it is imagewise exposed through an exposure optical system 14 whereupon the charge on the drum surface is selectively removed in accordance with the image of an original being copied to form an electrostatic latent image which is subsequently converted into a visual image by a developing unit 15 the developing unit 15 includes a housing 16 in which are fixedly mounted a non magnetic sleeve 17 a magnet 19 contained within the sleeve 17 and mounted on a shaft 18 for rotation and a quantity of magnetic toner 20 which is contained in the housing and attracted onto the sleeve 18 by the magnetic attraction of the magnet 19 when the magnetic toner 20 is attracted onto the.