| 摘要 |
PURPOSE:To eliminate malfunction and to preclude a decrease in image density at the end of toner by resetting the toner end in response to the recovery of toner concn. even after the toner end is displayed, and then performing normal toner concn. control again. CONSTITUTION:One sensor 14 consisting of a light emission part and a light reception part is provided behind the arrangement part of a developing sleeve 2 in the rotating direction of a photosensitive body 1 and where the image formation area of a reference pattern 13 passes. This sensor 14 detects reflected light from a toner image formed by visualizing the electrostatic latent image of the reference pattern 13 and transduces the light photoelectrically to generate a sensor output VSP. Further, the sensor detects reflected light from an exposed part of the photosensitive body 1, i.e. where no toner sticks originally after the reference pattern 13 passes and transduces the light photoelectrically to generate the sensor output VSG. The detection signal of this sensor 14 is decided by a central processor CPU and a signal based on the result is sent to a driving device 15 to drive a toner supply roller 7 and an agitation spring 9. |
