Device for controlling automatically toner concentration

Abstract

Abstract PURPOSE:To maintain always adequately the amt. of the toner to be mixed with a developer and to obtain a stable image by providing a duty cycle driving circuit for a toner replenishing motor and a continuous revolution circuit which can be driven by a replenishing switch. CONSTITUTION:The change in magnetic permeablility complying with toner concentration is detected by a sensor 9 and is compared with reference density by a comparator 11. A motor 15 is driven for required time by a timer circuit 13 and a relay circuit 16 to replenish the toner. The operator pushes a replenishing switch 17 to drive the motor 15 and a motor 21 for the developing machine for specified time by relay circuits 16, 20 in the casd of copying an original which consumes much toner. The rate of toner replenishment is thus kept at a regulated quantity by the intermittent driving of the motor 15. The opertor runs continuously the motor 21 to replenish the toner by pushing the switch 17 in the case of an original which consumes much toner. The toner concentration is thus maintained always with high accuracy and the stable image quality is automatically obtd.

Inventors

• 👤 Kiyoshi Hashizume
• 👤 橋爪　潔

Bibliographic Details