POWDER DEVELOPING DEVICE FOR ELECTROSTATIC LATENT IMAGE

摘要

PURPOSE:To avert the scattering of a toner generated below a modulating region by entraining the toner splashed from the or an image carrying surface in the air flow flowing between the image carrying surface and the edge of a developing device cover and capturing the toner into the cover. CONSTITUTION:The process for rotating a photosensitive drum 1 in an arrow 2 direction and making development by the toner 4 on a sleeve 5 constituting a modulating device 3 is the same as the ordinary process. A fan 14 is operated to discharge the air in a developing device cover 10 during the time when the sleeve 5 rotates in an arrow 9 direction and the development is executed. More specifically, a suction port 11A is provided between the surface of the drum 1 and the edge 11 of the cover 10 and the toner 4 splashed downward from the developing region is entrained in the air flow and is captured. The toner 4 which sticks on the surface of the drum 1 and tends to be transferred onto the edge 11 upon movement of the drum 1 near to the edge 11 by the rotation is also captured by the air flow passing the port 11A. In either case, the toner 4 is captured by the magnetic force of a magnet roll 6 and is returned onto the sleeve 5.