| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a developing apparatus or the like, configured to properly maintain toner concentration, while reducing cost, with a simple configuration.SOLUTION: A developing apparatus 26 includes: an agitation member 31 for agitating developer in a housing 30; a toner concentration sensor 34 that detects toner concentration; and a development control apparatus 35 which controls a toner supply motor 44 or the like. The toner concentration sensor 34 outputs a waveform oscillating between a peak value (Vp) and a bottom value (Vb) in accordance with a rotation period of the agitation member 31. The development control apparatus 35 calculates an index concentration (T/C(i)) indicating toner concentration, sets an intermediate value (V1/3) within a range of one period of the waveform, calculates a fluidity index value (F1/3) indicating fluidity of the developer on the basis of a ratio of a difference value (V1/3-Vb) with respect to a wave height (Vpp), and corrects the index concentration (T/C(i)) with a correction value (Va) based on the fluidity index value (F1/3), to calculate a control concentration (T/C(a)).</p> |
