| 摘要 |
PURPOSE:To simplify the constitution of a multicolor developing device and to reduce the size of the device by arranging a developing unit using one-component magnetic toner on the upper side changing the magnetic pole position of a magnet in a two- component developing unit arranged on the lower side by the developing unit and a non-developing unit. CONSTITUTION:A multicolor developing device 6 consisting of the 1st developing unit 4 for storing one-component magnetic black toner and the 2nd developing unit 5 for storing two-component non-magnetic color toner is arranged on the lower side of an exposure slit 3. A solenoid 32 is fitted to the free end of a rink 31 and the magnetic pole position of the magnet 22 is changed in accordance with the ON and OFF of the solenoid 32. The ON and OFF of the solenoid 32 correspond development and non-development. Namely, the solenoid 32 is turned off at time of non-development, and turned on only at the development. Consequently, the magnetic pole position of the magnet 22 in a developing sleeve of the 2nd developing unit 5 arranged on the lower side of the 1st developing device 4 using the one-component magnetic toner is changed in accordance with development and non-development, so that the one- component magnetic toner is prevented from being adhered to the developing roller of the 2nd developing unit storing the two-component non-magnetic toner. |
