| 摘要 |
PURPOSE:To prevent the degradation of toner characteristics and the production of suspended toner and make image density uniform and stable by providing means of rotating either one of a magnet roller or a developing sleeve at the reciprocating movement of a recording head and stopping the same during standby time other than this. CONSTITUTION:When a recording head 9 starts forward movement from the home position 9 shown by the solid line to the end position 9 shown by the alternate long and two short dashes line, an electromagnetic clutch 17 goes ON to connect a shaft 15a and the shaft 13a of a magnet roller. Then, the magnet roller 13 starts rotating by way of a motor 14 and a belt 16. When the head 9 ends the forward movement, recording paper P is fed and the paper feed also stops after the backward movement of the head is stopped. Thence, the magnet roller 13 stops when the electromagnetic clutch 17 is turned OFF by an ON-OFF control circuit 23. Hence, the supply of the excessive toner to a wedgelike space 21 is obviated during the standby time of the head 9, and there is neither degradation of the toner characteristics nor the production of the suspended toner, thus the image density may be made uniform and stable. |
