| 摘要 |
PURPOSE:To make the electrostatic charging amount of toner constant by appropriately stirring developer in accordance with the supply quantity of toner, and to reduce the scattering of toner and the fogging of white surface caused by the shortage of stirring by preventing the lowering of image density and the deterioration of the developer caused by excessively stirring the developer. CONSTITUTION:The stirring roller 4 of a developing device is driven through a revolving speed control part 6. In the case of supplying the small quantity of toner, the roller 4 is driven at a low speed through a gear G1, a clutch CL1, a gear G4 and a roller shaft 4. In the case of supplying the large quantity of toner, it is driven at a high speed through the gears G1 and G2, a clutch CL2, the gears G3 and G4 and the roller shaft 41. |
