DEVICE FOR DETECTING AMOUNT OF REMAINING TONER FOR IMAGE FORMING DEVICE

摘要

PURPOSE:To detect highly accurately and stably the amount of toner remaining in the hopper of a printer. CONSTITUTION:A sensor 144 for detecting an amount of remaining toner, composed of a thickness-shear vibrator 145, is disposed on the wall surface of the hopper so that toner touches the parallel surface of the thickness-shear vibrator 145 in the direction of vibration. A change in viscosity resistance in which the contact of air with the contact surface differs from the contact of toner with it is detected as a change in the inpedance of the thickness-shear vibrator 145.