Patent ID: 6259883
Filing Date: 2001-07-10
Classification: G03G

Abstract:
An image forming apparatus comprising:a developing unit having a photoreceptor, the developing unit for making an electrostatic latent image on a surface of the photoreceptor visible as a toner image;a toner hopper for storing toner to be supplied to the developing unit;a cleaning device for removing and recovering the toner remained on the surface of the photoreceptor after the toner image has been transferred onto a recording material;a toner transporting passage connected between the cleaning device and the toner hopper, through which the toner recovered by the cleaning device is returned to the toner hopper;a toner exhausting port disposed at a part of the toner transporting passage, from which the toner being returned from the cleaning device side is exhausted outside the toner transporting passage; andan opening and closing member which selectively opens or closes the toner exhausting port,wherein an inner diameter of the toner exhausting port is made larger than that of the toner transporting passage.