| 摘要 |
PURPOSE:To make constant density of picture and to prevent dirt of background, by controlling toner density through the use of change in flow of a development agent, by naturally falling the development agent flowing to a development section in a detecting plate having a specified area and detecting the resistive force. CONSTITUTION:When a toner density is less than a set value, the flow in a development agent flowing from a funnel 3 is increased, a resistance of a detecting plate 4 is increased, the plate 4 turns downward to press a contact 5b, and toner is supplied to a development section from a toner supply device 6. Next, when the toner density is increased than the set value, since the flow of the development agent flowing down the detection plate 4 is less, the resistance received by the plate 4 is smaller, a contact 5b turns on to off and the supply of toner is stopped. Thus, the toner amount in the development agent is controlled constant. |
