| 摘要 |
PROBLEM TO BE SOLVED: To maintain toner concentration in developer as well as developing performance and further to keep the total amount of the developer at a specified level by replenishing a developing device using two-component-developer with toner or carrier. SOLUTION: Respective hoppers 200T and 200C for the toner T and the carrier C and disposed at the most upstream position of a stirring screw 147 of a pair of stirring screws rotating in mutually opposite direction and a barrier 184 and a recovery tube 300 for the developer are provided at the most downstream position of the other stirring screw 146, so that the excess amount of the developer D due to the replenishment of the toner T or the carrier C gets over the barrier so as to recovered by the tube 300. |
