IMAGE FORMING DEVICE WITH TONER RESIDUAL QUANTITY DISPLAY FUNCTION

PURPOSE:To eliminate erroneous detection by inputting the detection signals of a toner residual quantity detecting sensor to an operation control means, operating a toner carrying means, actuating a display means, thereby displaying the residual toner quantity when a toner empty detecting signal is obtained after the operations. CONSTITUTION:The signal of a toner concentration sensor 6 is inputted to a toner concentration lowering detecting means 13. When the toner concentration in a developing part C is detected to be lower than a prescribed level, motors M1 and M2 are driven by a motor driving means 15 instructed by the toner concentration lowering detecting means 13. A toner empty detecting voltage of the toner residual quantity sensor 4 is degitalized by an A/D converter 11 into a signal, which is inputted to a toner replenishing LED turning-on deciding means 14, and by issuing an instruction to the motor driving means 15, the motor M1 is driven and toner uneveness is corrected by a ladder chain 2. When the toner empty signal is continuously obtained afterward, a LED driving means 16 is instructed and thereby turning on a LED 17 and displaying the demand for toner replenishment. Thus, erroneous detection can be eliminated.