| 摘要 |
PURPOSE:To prevent sticking of toners on optical parts by the electrostatical repulsive force among the toners, by providing a wire which is extended on an optical path by facing optical parts and applying the potential of the same polarity as that of the toners on these wires. CONSTITUTION:The light transferred to a photosensitive drum 9 is imaged on the surface thereof, by which electrostatic latent images are formed, are developed and transferred. wherein the efficiency of reflection is decreased by the floating toners stuck on optical parts. In a dust-proofing device 10, the 4th mirror 8 is placed on the bottom part in an insulation case 11, and openings 12, 13 are formed in the inlet and outlet of the optical path L in the upper part thereof. Plural pieces of conductive wires 14, 15 disposed at equal intervals are held on the inside surface of the case 11 by means of conductive supporting plates 16, 17. The plates 16, 17 are connected to a DC electric power source 19 via lead wires 18, and for example, when the toners are charged negative, the negative potential is applied thereon. The entry of the toner into the insulating case 11 is prevented by the electrostatical repulsive power generated between th wires 14, 15 and the toners, whereby sticking of the toners to the mirror 8 is obviated. |
