| 摘要 |
PROBLEM TO BE SOLVED: To properly control the toner concentration of a developer by accurately detecting the toner concentration. SOLUTION: This device is provided with a steering roller 6 having a spiral wing 15 for stirring the developer housed in a developer container 2, while carrying the developer in an axial direction, in a developing part. Then, a toner concentration detecting means 12 for detecting the toner concn. is installed along the stirring roller 6 and in a position facing the installation part of the toner concentration detecting means 12, a stirring blade 16 projected in a direction perpendicular to the shaft of the stirring roller 6 is disposed between the surfaces facing each other of the spiral wing 15. The projecting quantity of the stirring blade 16 is set at a value smaller than that of the spiral wing 15. |
