| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing apparatus or the like, configured to appropriately maintain toner concentration regardless of the change in linear velocity of an agitation member or fluidity of developer.SOLUTION: A developing apparatus 26 includes: an agitation member 31 which rotates in a housing 30 to convey/agitate two-component developer; and a development control apparatus 35 which controls toner supply on the basis of a result detected by a toner concentration sensor 34 which detects toner concentration. The agitation member 31 is rotated by a plurality of liner velocities. The development control apparatus 35 executes degradation detection control which determines degradation of developer, and output correction control which calculates toner concentration. In the output correction control, the agitation member 31 is driven while changing the linear velocity, a plurality of output values (Vn, Vm, Vl) output from the toner concentration sensor 34 are stored by linear velocity, differences between the output value (Vn) of a standard linear velocity and each of the output values are calculated as multiple correction values (&Dgr;Vn, &Dgr;Vm, &Dgr;Vl). The output values are corrected with the correction values, to calculate a control value (M). |
