| 摘要 |
PURPOSE:To maintain the processing capacity of the total device constant by increasing conveyance interval of transfer papers when the temp. of a fixing device lowers to or below a prescribed value during successive fixing operation. CONSTITUTION:When a fixing device reaches, e.g., 150 deg.C after turning of a power supply, fixing rollers 31-1, 31-2 are reduced in rotation speed, and when it reaches, e.g., 170 deg.C, they are raised in rotation speed and come into a stand-by state. The temp. is controlled to keep it, e.g., at 180 deg.C during the stand-by. When the temp. lowers to or below 150 deg.C, copying operation is made impossible. When the copying operation is continued, the heat of the fixing device is absorbed to the transfer papers to lower the temp. When the temp. of the device lowers to a prescribed temp., e.g., 160 deg.C, copying intervals are enlarged by changing a sequential control, and when the device rises to 170 deg.C, it is returned to the normal sequential control. |
