| 摘要 |
PURPOSE:To obtain an image forming device capable of accurately detecting the concentration of the toner of a developing unit by predicting fluctuations in the output of a toner concn, sensor and attaining correction. CONSTITUTION:Timers are prepared for developing units for each color 14 17, respectively and count time from the start of driving to that of the output detections of toner concn. sensors 14c-17c, to obtain a correcting quantity corresponding to the time from the previously obtained correcting table. Then, the outputs of the detections of time toner concn. sensors 14c-17c are corrected by the obtained correcting quantity, to decide the concn. of the toner. Thus, even if the deviatior between the output of the detection of the toner concn. sensor and the actual toner concn. is generated under certain conditions, the output of the toner concn. sensor or a toner concn. control reference value is properly corrected to control the processes of the replenishment of the toner, etc. Moreover, the fluctuations in the output of the toner concn. sensor until the flow of a developer in the developing unit is stabilized are predicted so that the output of the toner concn. sensor or the toner concn. control reference value can be properly corrected. |
