| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device that can adjust a difference between biases to be applied to a developer supply member and a developer carrier to an appropriate value to achieve a sufficient amount of supply of a developer.SOLUTION: A toner supply amount adjustment operation includes: initially a removal operation to remove a toner remaining on surfaces of a developing roller 13 and a supply roller 26 by forming a solid image (patch B1) (step S2); and subsequently a bias difference adjustment operation to determine a necessary bias difference Vx by calculating a primary approximate expression of a bias difference Va and an adherence amount Ma, Ma=a*Va+b from the amount of adherence from a patch B2 to B4, M2 to M4.SELECTED DRAWING: Figure 3 |
