| 摘要 |
PROBLEM TO BE SOLVED: To provide an environment control device that controls environment in a control target area in an image forming apparatus and that is able to reduce abnormal images resulting from partial toner softening or melting in the control target area.SOLUTION: A temperature sensor is provided in each developing device 5. A lower limit temperature T1 min at which charging failure of toner is prevented in each developing device 5 and an upper limit temperature T1 max at which toner is prevented from softening or melting in the developing device 5 are obtained in advance. T1 and T2 that have the relation expressed by T1 min<T1<T2<T1 max are prescribed. An intermediate value between T1 and T2 is determined as a target value T3 used for feedback control. At least in a heating operation performed for a rapid heating operation (S3) or feedback control (S6), a controlled air current supplied to each heating or cooling jacket 56 disposed in close contact with each developing device 5 is set equal to or below a predetermined temperature such as a glass transition point temperature Tg min. The degree of heating is controlled by increasing or decreasing the flow rate of air current controlled by each flow rate control valve 55. |
