| 摘要 |
PURPOSE:To obtain uniform and excellent development effect and to facilitate maintenance inspection by holding an electrostatic latent image holder and a toner carrier opposite in body at a specific interval, and allowing a toner supply part and the toner carrier while toner is shielded from the toner supply part side. CONSTITUTION:Toner is supplied onto a developing roll 2 from an opening part 6a and the conveyed to the upstream-side contacting position on a layer thickness control member 7 while charged electrostatically by friction through the rotation of the developing roll 2. Then, the layer thickness control member 7 held to specific contact pressure with the elastic force of an elastic member 9 controls the toner into a thin uniform layer at the contacting position. When a developing unit B is replaced, a solenoid 11 is put in operation firstly to rotate a toner tank bottom wall 63 to the position where a toner tank 6 is separable, and the solenoid 11 and a spring member 12 are disengaged from each other to place the developing unit B in a free state; and the developing unit B is rotated as shown by an arrow Y, i.e. drawn in such a direction that the unit separates from the developing roll 2. |
