C. Controlling the Fixing TemperatureThe surface temperature of the machine's upper fixing roller is monitored by the mainthermistor (TH1); measurements are taken and communicated to the microprocessor onthe DC controller PCB.The DC controller PCB uses these measurements to vary the main heater drivesignal (MHRD) and the sub heater drive signal (SHRD).The sub thermistor (TH2) is mounted at the rear of the upper fixing roller to check foran abnormal increase in temperature.Figure 6-102Upper fixing rollerFixinglowerrollerPS47Fixing assembly outlet paper detection signal (FXDEL) J108-B4Claw jam detection signal (PS52D) J108-A19Cleaning belt length detection signal (CBOP) J108-A13Main thermistor signal (TH1) J108-A15Main heater drive signal (MHRD*) J102-B5Sub heater drive signal (SHRD*) J102-B3Main thermistor (TH1)AC power supplyTPICleaning beltguide plateThermalswitchAC driver PCBPS11PS52Sub thermistor signal (TH2) J108-A9DC controller PCBSub thermistor(TH2)CHAPTER 6 FIXING SYSTEM6-5COPYRIGHT © 1997 CANON INC. CANON NP6560/NP6360/NP6260 REV. 0 NOV. 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
