| 摘要 |
PROBLEM TO BE SOLVED: To shorten the heating time of a fixing roller and to make heating efficiency excellent by inhibiting the image forming action of both surfaces and enabling the image forming action of one surface to be executed when the temperature of a fixing member faced to the front surface of a transfer paper is proper and the temperature of a fixing member faced to the back surface of the transfer paper is lowered. SOLUTION: A fixing unit 17 is constituted so that the surface temperature of an upper roller 17a is detected by an upper thermistor 173 and the surface temperature of a lower roller 17b is detected by a lower thermistor 174. By a heater control means 21, an upper and a lower heaters 171 and 172 are controlled to be turned on or off according to the respective temperature detected by the thermistors 173 and 174. When a continuous copying action is executed in a one-surface copying mode, the heater 172 is turned off. When a both-surface copying mode is inputted from a control panel 22 in such a state, the copying action is inhibited until the temperature of the upper roller becomes >= the threshold temperature thereof and the temperature of the lower roller becomes >=the threshold temperature thereof. Then, when the condition is satisfied, the both-surface copying action can be executed. |
