| 摘要 |
PURPOSE:To reduce necessary driving torque and reduce the weight, size, and cost of the developing device of a copying machine by forming a metallic plating layer on the roll-shaped surface of a specifying member which specifies the thickness of a developer. CONSTITUTION:The specifying member 17 is provided rotatably over a developing roll 15 in press contact, and the member 17 is formed by providing an elastic layer 17B and the metallic plating layer 17C on the outer circumference of a metallic core 17A. A onecomponent nonmagnetic developer 14 is specified to uniform thickness by the press contacting force and relative speed difference of the specifying member 17, and the coefficient of friction of the plating layer 17C is 0.1-0.3, so the necessary driving torque is reduced to simplify a housing, bearings, etc., thereby reducing the weight, side, and cost. |
