| 摘要 |
PURPOSE:To detect accurately the fullness of a recovered toner with a simple constitution by using the packing pressure of the recovered toner to move a plunger and operating an optical sensor. CONSTITUTION:A carrying screw 11 is arranged in a remaining toner recover box 14 of a picture image forming drum 1, and a projecting part 14b is provided in its front end part in the carrying direction. A plunger 15 is provided in the projecting part 14b vertically movably, and an optical sensor 17 is arranged near its small-diameter end part 15d. When the quantity of the accumulated toner in the recovery box 14 is increased in this constitution, the packing pres sure due to the carrying force of the screw 11 is generated, and the plunger 15 is pushed up by this pressure, and the sensor 17 is cut off to generate a signal. Thus, the fullness of the recovered toner is detected accurately with the simple constitution without using a complicated sensor circuit. |
