| 摘要 |
PURPOSE:To perform invariably stable transfer and separation by setting discharging current values and AC component frequencies of electrostatic charging before transfer, transfer charging, and separation charging to optimum values according to the kind of toner used for development. CONSTITUTION:The 1st developing device 13 and the 2nd developing device 14 contain different kind of toner. A high voltage controller 30 is provided to select current values of electrostatic charging, transfer charging, and separation charging which are optimum for various characteristics of toner in use. A before-transfer electrostatic charger 15, transfer charger 18, and separation charger 19 are put in discharging operation with the selected values. |
