| 摘要 |
PROBLEM TO BE SOLVED: To prevent erroneous mounting and to restrain production cost by performing heating control in accordance with the performance of a heating element and performing the temperature control of a fixing device in accordance with paper size. SOLUTION: By turning on a switching element Tr1 and a heater driving element Tr2 or Tr3, voltage is impressed on heaters for fixing Ha and Hb. The heater Hb having the peak of light distribution at the center part of the fixing roller and the heater Ha having the peak of light distribution at both ends of the fixing roller are connected. Respective heater driving signals FSRDA and FSRDB are outputted to the elements Tr2 and Tr3 so as to judge the state of the temperature rise of a thermistor Th and judge what type of a heater is connected to the elements Tr2 and Tr3. Then, the heating control is performed in accordance with the performance of the judged heater. In such a case, when a printing command is given, the turning-on ratio of the heaters Ha and Hb is varied according to the paper size, so that the optimum temperature control is performed on paper. |
