| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device configured to stabilize developer discharge performance in a part of a conveyance screw along an outlet, and to prevent the developer from being excessively increased in a developing device even if the developer is deteriorated or in a high-humidity environment.SOLUTION: An area of a developing screw 3a along an outlet 40 has no screw blade 3p, and is larger in vertical cross sectional area of a central shaft than an area with the screw blade 3p. The area of the developing screw 3a along the outlet 40 is larger in the vertical cross sectional area of the central shaft than the outside thereof, in a range larger than the outlet 40 in an axial direction of the developing screw 3a. |
