Toner remainder detector of electrophotographic copier

Abstract

Abstract PURPOSE:To exactly detect the amount of toner remainder, by electrically catching decrease of torque in the drive motor of a developing unit. CONSTITUTION:Drop of development torque can be caught as drop of the current of a drive motor circuit. The current value of drive motor 7 of a developing vessel can be caught by resistance 9 as voltage change. This voltage is rectified and amplified and sent to comparator 12, where a reference voltage is set to the voltage level corresponding to current Ci at the limit point of developing ability due to consumption of the toner, and the above detected value is compared with this set value. When the detected value exceeds the set value, comparator 12 provides a signal to indicate this state in display device 13, permitting the toner remainder limit to be exactly detected.

Inventors

• 👤 Koji Maruyama
• 👤 Mitsuo Hayashi
• 👤 Takao Yorifuji

Bibliographic Details