| 摘要 |
PURPOSE:To ventilate the inside of a shield member smoothly to prevent foreign matters form sticking to a discharging member by providing a means which blows forcibly a wind into the shield member and constituting a part of the shield member with a wind discharge wall which can discharge the wind. CONSTITUTION:A very narrow corona discharging wire 2 which is connected to a DC high-voltage power source 1 to constitute the discharging member is stretched, and a body 3 to be electrified as an electric charge acceptor is provided in the position facing the wire 2, and they are so constituted that corona discharge occurs. An air duct 6 is provided in an inflow port 5 of a metallic shield member 4 and a blast fan 7 is provided in the end part of the duct 6 so that the inside of the shield member 4 is ventilated forcibly. When the wind is blown forcibly form the fan 7 into the shield member 4, a clean air is blown to the corona discharging wire 2 and is discharged to the outside of the shield member 4 from meshes 9 and the gap between the lower end of the shield member 4 and the body 3 to be electrified, and therefore, a turbulent flow is not caused in the shield member 4 to prevent whirling of foreign matters 10 like toner and sticking of them to the wire 2. |
