| 摘要 |
PURPOSE:To detect the quantity of toner remaining in a toner vessel as well as control the toner concentration with a high precision without especially providing a remaining toner quantity detecting sensor by effectively using a toner concentration sensor arranged in a developing vessel. CONSTITUTION:A slit aperture part 6a is provided in the bottom of a tapering guide recessed part 6 formed in an arbitrary position of a partitioning plate 5, and a toner replenishing roll 7 coated with sponge is freely rotatably attached in the aperture part 6a, and a DC motor M coupled to the roll 7 is rotated and controlled to arbitrarily adjust the quantity of toner to be replenished. Meanwhile, a rotatable agitating member 8 is attached in the center part of a developing vessel 1 to agitate toner replenished from the roll into the vessel 1 together with carrier. A toner concentration sensor 10 is attached to the vessel bottom under the member 8, and not only driving and stop but also rotation of the motor M is controlled (toner replenishment control) based on the detection signal from the sensor 10. |
