| 摘要 |
PURPOSE:To control the toner concentration of a developer stably with high accuracy by controlling the toner density based on the operation point of a toner sensor. CONSTITUTION:The toner sensor 7 is fitted on the side wall, etc., of a developer container 2 so that a detection part contacts the developer 1 and the operation point of this toner sensor 7 is varied and set with a current flowing through a control line (a) or an applied voltage. A microcomputer 8 inputs the output of the toner sensor 7 through an output line (a) and sends a control signal to the toner sensor 7 through the control line (b) so that the operation point of the toner sensor 7 has a proper value, thereby controlling the current or voltage. The operation point of the toner sensor 7 is therefore set to the proper value automatically. Consequently, the toner density is controlled stably with high accuracy. |
