| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a developing device configured to stabilize nonmagnetic toner concentration in a container of the developing device that uses two-component developer containing nonmagnetic toner and magnetic carrier, and an image forming apparatus having the same. <P>SOLUTION: A magnetometric sensor S is arranged at the bottom of a developing container 15 of a developing unit 10. It is assumed that, as a sensitivity characteristic of the magnetometric sensor S, toner concentration in the developing container 15 has a linear function of an output voltage value of the magnetometric sensor S. Measurement is carried out at two points in order to determine two constants of the linear function. For the first point, an output voltage value measured from toner concentration in a new developing unit 10 is used. For the second point, an output voltage value measured from toner concentration after a predetermined amount of toner is supplied from the new developing unit is used. <P>COPYRIGHT: (C)2013,JPO&INPIT |
