| 摘要 |
PROBLEM TO BE SOLVED: To provide a multi stage developing device which can achieve stable development by use of simple and low-cost constitution without increasing drive torque, while preventing a developer from being directly supplied to a lower developing roller. SOLUTION: A magnet (not shown in the figure) forming an N-pole which pumps up a developer supplied by an agitating paddle 8 is provided inside an intermediate developing roller 3 and is placed so that the N-pole is in a position opposite to a lower developing roller 4. Further, the N-pole is located between a line A connecting the center of the intermediate developing roller 3 to the center of the lower developing roller 4 and a line B which is a tangent extended from the center of the intermediate developing roller 3 onto the outer periphery of the lower developing roller 4 in the opposite direction to a photoconductor drum 1. |
