| 摘要 |
PURPOSE:To prevent the toner clogging of the toner passing orifice provided to a control electrode, by applying voltage having polarity opposite to that of voltage applied to a toner carrier electrode to the control electrode between the toner carrier electrode and a rear surface electrode. CONSTITUTION:A chargeable toner layer 22 is formed to the surface of a toner carrier electrode 15 and a rear surface electrode 20 is arranged thereabove while recording paper 21 is contacted with the lower surface of said electrode 20 and a control electrode 16 having a toner passing orifice 19 is provided between said electrodes 15, 20. A toner releasing power source 48 for supplying voltage having the same polarity as the charged polarity of toner and a toner recovery power source 49 having opposite polarity are connected to the toner carrier electrode 15 so as to be changed over by a switch 50. Voltages having the same polarity as that of the toner 22 is applied to the control electrode 16 from two power sources 26, 27 by the switch 50 and a synchronous operation switch 28. By this method, density irregularity can be prevented. |
