| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent toner concentration from getting too high or too low in an early stage of starting operation of a developing device which develops an image with two-component developer without directly detecting the toner concentration. <P>SOLUTION: The density detection value of a reference image developed by the developing device at the beginning of starting the operation of the developing device is stored as an initial density detection value. When correcting a toner supply amount so that a toner cumulative supply amount may be within a tolerance (within a range of an upper limit and a lower limit shown in the figure) specified by a range of tilt to a change of the cumulative value of the image density of the image developed by the developing device, if it is the early stage of starting the operation of the developing device and the initial density detection value is larger than an upper limit reference value (initial density is lower than lower limit density), the tilt of the upper limit of the tolerance is made small (referring to the upper limit of the early stage of starting the operation), and if it is the early stage of starting the operation of the developing device and the initial density detection value is smaller than a lower limit reference value (initial density is higher than upper limit density), the tilt of the lower limit of the tolerance is made large (referring to the lower limit of the early stage of starting the operation). <P>COPYRIGHT: (C)2011,JPO&INPIT |
