| 摘要 |
PROBLEM TO BE SOLVED: To prevent an image from becoming indistinct, when the remaining amount of toner inside a developing device is reduced, and thereby a specified layer is not formed on a developing roll. SOLUTION: This device is constituted so that a control blade 2 is held in press contact with the developing roll 1 by a specified pressing force of a pressure adjusting spring 3; an angleθ, formed by a perpendicular and a tangent on a contact point where the control blade 2 is held in contact with the developing roll 1, is made possible to be varied with an axis at the contact point of the control blade 2 and the developing roll 1; then the developing device weight detector 7 is made possible to sense the residual toner inside the developing device by weight of the developing device and to move the control blade 2 up and down across a fulcrum 9; the angle formed by the perpendicular and the tangent on the contact point where the control blade 2 is held in contact with the developing roll 1, is varied corresponding to the residual toner inside a hopper 10; therefore the toner layer of the specific thickness is formed on the developing roll 1, regardless of the decrease in the remaining amount of toner. |
