| 摘要 |
PURPOSE:To obtain an image forming device provided with a filter excellent in the inhaling properties of outside air and the collecting ability of fine powder and dust, on the intake of the outside air. CONSTITUTION:When positive and negative high voltages are applied to the filters 4 and 5 from an external feeder part, materials which have positive and negative potentials and are induced/electrified, such as the fine powder and the dust 15-17 in the outside air which are sucked from a cooling fan 2, are attracted/collected to the filter mediums 4 and 5. On the other hand, the dust or the fine powder 18 which are not electrically attracted, are mechanically filtered. Thus, the meshes of the filter mediums 4 and 5 are roughened, and the sucking resistance of the cooling fan 2 is reduced, so that the cooling fan 2 can be made small. Further, wind cutting noises on the filter mediums 4 and 5 are reduced. |
