| 摘要 |
PURPOSE:To accurately detect the toner concentration in a developing agent by providing plural developing agent density detecting means in an area formed by developing agent carrying mechanisms and a developing agent carrying body and, at the same time, controlling the toner concentration based on detecting signals from the detecting means. CONSTITUTION:This developing device is provided with a developing agent container (housing) 6 for housing a two-component developing agent D composed of toner and a carrier and plural developing agent density detecting means 18A and 18B which are face to a developing agent carrying body 2 and detect the toner concentration in the developing agent D carried on the carrying body 2 are provided in an area formed in the housing 6 by developing agent carrying mechanisms 4 and 5 and the developing agent carrying body 2. Then the toner concentration in the developing agent D is controlled by performing a prescribed calculating process based on toner concentration detecting signals outputted from the means 18A and 18B. Therefore, the toner concentration in the two- component developing agent D in the housing 6 can be detected accurately. |
