| 摘要 |
PURPOSE:To improve toner feeding properties to a developing roller by impressing DC voltage with polarity reverse to the polarity of a developer on a developing roller, a developer feeding member and a layer-thinning regulation member and setting specific conditions among respective impressed voltages. CONSTITUTION:Respective DC voltages with polarity reverse to the polarity of the developer are impressed on the developing roller, the developer feeding member and the layer-thinning regulation member, and when the voltages impressed on respective members are defined as VR, VSP and VR/P, the relation of ¦VR¦<=¦VSP¦ (A) and ¦VR¦<=¦VR/P¦ (B) is formed among respective impressed voltages. When the relation of (A) is formed, the electrical potential of the developing roller 6 with the charge of toner forms the trough of potential with respect to the electric potential of a toner feeding member 5 at the time of feeding toner from the member 5 to the roller 6. Consequently, the toner feeding property from the member 5 to the roller 6 is improved and uneven feeding can be removed. When the relation of (B) is formed, the distribution of toner charge is suppressed and the developing state can be kept at an excellent state free from ground stain. |
