| 摘要 |
PURPOSE:To perform automatic image density control by controlling the rotation of a toner supply motor according to a toner supply rate set for every copying machine irrelevantly to the on-off state of a toner increases switch during automatic image density control. CONSTITUTION:When an automatic density control 15 outputs a toner supply motor ON signal 18 to a toner supply control circuit 19 during automatic image density control, the toner increases switch control part 152 of the automatic density controller 15 goes up to 'H' and a signal line 16' through which the signal is sent from the automatic controller 15 to the control circuit 19 goes down to 'L', thereby entering the same state with the on state of the toner increase switch 24. The rotation of the toner supply motor 19 is controlled with the motor ON signal from the controller 15. Even if the toner increase switch 24 is turned on artificially, it is judged that the toner increase switch 19 is off as long as the toner increase switch control port 152 is at 'H'. Consequently, a copy having invariably stable density is obtained. |
