| 摘要 |
PURPOSE:To properly carry out a correction with respect to a reference voltage and to control a toner concentration constant by measuring toner consumption per one sheet based on picture data, and correcting the relative relation of a reference value and a concentration detecting signal based on the measured toner consumption. CONSTITUTION:The number of dots D is counted from the picture data, and average toner consumption is calculated from a value that the number of cumulative dots ND when the prescribed number of sheets is copied is divided with the number of copies. When the toner consumption per one sheet is a lot, it is discriminated that the frequency by replenishing flesh toner is large and the removement of a post-treating agent, etc., are lessened, so that the correction is carried out with a comparatively small correcting quantity. On the other hand, when the toner consumption per one sheet is little, it is decided that the frequency for replenishing the flesh toner is little, and the removement of the post-treating agent, etc., comparatively is generated largely so that the correction is carried out with a comparatively large correcting quantity. Thus, a proper correction is carried out with respect to the reference voltage, and toner concentration control is carried out with high precision. |
