TWO-PART DEVELOPING DEVICE

PROBLEM TO BE SOLVED: To provide a two-part developing device capable of preventing developer from overflowing from a case in the downstream area of a second developer storage section in the direction of developer conveyance, by making the diameter of the second developer stir member smaller in the downstream area in the direction of the developer conveyance. SOLUTION: In the second stir roller 3, the diameter of a shaft 3a, which part corresponds to the downstream area m in the direction of the developer conveyance is made smaller than that of the shaft 3a, which corresponds to the upstream area l. Thus, an amount of gap between the second developer storage section 7b and a second stir roller shaft is made larger in the downstream area than that in the upstream area. This prevents the position of the uppermost surface of developer from moving upward even when the amount of developer in the downstream area in the direction of the developer conveyance increases. COPYRIGHT: (C)2006,JPO&NCIPI