| 摘要 |
PURPOSE:To prevent the occurrence of an image defect after the replacement of a development unit and to make it possible, even when the development unit is replaced, to use developer contained in the development unit before the replacement, in an electrophotographic device using the two-component development device. CONSTITUTION:Each time an image forming operation is carried out by an image forming part 20, the concentration of developer 23 is detected by a T sensor 21, and the output of the detection is stored in the memory of the device main body. In the case of the detachment of the development unit 22, detection outputs of the T sensor 21 before and after the detachment are compared. When the output difference exceeds an allowable range, the operation of the device is stopped the adjustment of the output of the T sensor 21 by a service man is executed. |
