| 摘要 |
PROBLEM TO BE SOLVED: To decrease a reduced concentration of a toner, which occurs regardless of the toner remaining when a toner residual amount in a developing device 4 decreases.SOLUTION: A substantially closed region T segmented by at least a supply roller 19, a developing roller 17 and contact means 22 is formed in a developing device 4, the substantially closed region T which includes a region located at an upstream side on a surface of the supply roller 19 than a position in contact with the contact means, along the moving direction of the surface of the supply roller 19, as well as at a downstream side than a contact part with the developing roller 17 along the moving direction of the surface of the supply roller. The position where the contact means 22 is in contact with the surface of the supply roller 19 is at the downstream side of the contact part with the developing roller 17, along the moving direction of the surface of the supply roller 19; and a deformation amount of the supply roller 19 in a direction where the radius of the supply roller 19 decreases (in a compression direction) is larger than 0. |
