| 摘要 |
PURPOSE: To supply toner in response to its consumption and to stabilize an image density by detecting the writing area ratio of an electrostatic latent image and setting a supplying developer quantity, time to supply the developer and supplying timing in accordance with the area ratio. CONSTITUTION: In a correcting circuit 20, a reference value on the adjustment of the consumption of the toner is registered, correction processing for a supplied toner quantity is executed based on a detected voltage value VTC from a toner concentration sensor 10 and a signal SOU for instructions for the supplied toner quantity set by the processing is outputted to an image forming device control circuit 11. Thus, the control circuit 11 outputs a signal STA for controlling the driving state of a supplying member 4E2 for supplying the toner of the quantity corresponding to the corrected supplied toner quantity. At this time, the writing area ratio of the latent image by a writing scanner 3 for irradiating a photoreceptor drum 1 with scanning light for forming the electrostatic latent image is detected and the supplied toner quantity, the time to supply the toner and the supplying timing are set in accordance with the detected area ratio. |
