Detection for level lowering of sensor in toner density controller

Abstract

Abstract PURPOSE:To detect accurately the dirt of a toner mark sensor, by checking the signal of the form ground part in a device which reads the density of the toner mark to detect the toner supply time. CONSTITUTION:The reflected light from a toner mark 18 stuck to a form 9 is detected by a photodetector 19b to detect the toner density. When this toner density becomes lower than a reference value 30, the toner is supplied. The reflected light from the ground part of the form 9 is detected also and is amplified in an amplifier 24 and is integrated in an integrator 25 and is inverted by a code inverter 26 and is compared with a reference value 28. When an output V0' of a comparator 27 is inverted, the lowering of the photodetection capability due to the dirt of an optical sensor is discriminated.

Inventors

• 👤 Hirotoshi Shimizu
• 👤 清水　宏利
• 👤 Yoshio Iino
• 👤 飯野　良雄
• 👤 Akio Nakanishi
• 👤 中西　暁雄

Bibliographic Details