| 摘要 |
PURPOSE:To eliminate background staining and scattering of toner due to the supply of a large amount of toner in a short time by lowering a toner supply rate to a minimum supply level temporarily when detecting a sensor output indicating a deficiency in toner during image formation right after a toner container is replaced, and then increasing the toner supply rate gradually. CONSTITUTION:One sensor 14 consisting of part of a light emitting part and a photodetection part is provided where the image formation area of a reference pattern 13 passes. This sensor 14 detects reflected light from a toner image obtained by visualizing an electrostatic latent image of the reference pattern 13 and converts is photoelectrically to send out a sensor output VSP. Reflected light from an exposed part of a photosensitive body, i.e. a part where no toner sticks originally is detected after the reference pattern 13 passes and converted photoelectrically to generates a sensor output VSG. The detection signals of the sensor 14 are decided by a central processor CPU, which sends a signal to a driving device 15 on the basis of the result to drive a toner supply roller 4 and an agitation spring 5. |
