| 摘要 |
PURPOSE:To stabilize always the sensor output to control the density more accurately by providing a sensor for density detection so that this sensor faces a sleeve constituting a developing roll and providing a plate which controls a developer flowed to the sensor so that this plate faces the sensor. CONSTITUTION:A sensor 20 is attached to an upper cover 18 of a developing tank 19 and is attached a considerable length apart froma sleeve 10 so that the center of the sensor 20 coincides with the center of a pole N2 of a magnet 11. An obstructive plate 17 which controls the flow of the developer is provide below the sensor 20 in the developer carring direction, and this obstructive plate 17 has one end fixed to the upper cover 18 and suppresses carying of a part of the developer 2 which is flowed to be brought into contact with the sensor 20. When the developer passes the sensor 20, a part of the flow of the developer is controlled by the action of the obstructive plate 17 to accumulate the developer in the entrance side of the sensor 20. That is, the obstructive plate 17 is provided to control the quantity of the developer flowed to the sensor 20, and the quantity of the developer flowed to the part of the sensor 20 is kept constant. |
