| 摘要 |
PROBLEM TO BE SOLVED: To make uniform the thickness of a toner layer by varying the resistance value of a supply roller in compliance with the distortion of a doctor blade. SOLUTION: A supply roller 22 is formed so that its resistance value increases in the central part in the axial direction in case a doctor blade 26 is distorted and its pressing force lowers in the central part in the longitudinal direction, and the potential difference between the surface of the supply roller 22 and the surface of a developing roller 24 is lessened, and the toner supplying amount to the developing roller 24 is decreased in the central part. Therefore a unifrom thickness of toner layer in the axial direction is established even if the pressing force of the doctor blade 26 is lesser in the central part. |
