Fuser temperature control The fuser temperature control maintains the target surface temperature of the fuser sleeve. Figure 1-7 Fuser temperature-control circuit DC controller Fuser sleeve temperature protection The fuser heater controls the temperature of the fuser sleeve. The DC controller detects the center area temperature by monitoring the main thermistor. The DC controller controls the FIXING HEATER CONTROL (FSRD1) signal, so that the fuser sleeve remains at the targeted temperature. ● Protective function : The protective function detects rising temperatures in the fuser and interrupts power to the fuser heater.
The following four protective components prevent the fuser sleeve and pressure roller from excessive rising temperature: ◦ DC controller ◦ Fuser heater safety circuit ENWW Engine-control system 15 Fuser Low-voltage power supply Fuse Zerocross /ZEROX circuit FSRD1 Fuser sleeve unit Fuser heater Relay /RLD control circuit Relay control TH1 circuit TH2 TP1 TH3 CPU H1 Current Relay detection circuit FSR CURRMS _ Pressure roller Fuser heater safety circuit FSRSAFE1 H1: Fuser heater Fuser heater safety circuit FSRSAFE2 TP1:T hermoswitch Fuser control circuit TH1: Main thermistor Fuser heater TH2: Sub thermistor 1 /FSRNEW safety circuit TH3:
Sub thermistor 2 /FSRSNS FSRTH3 FSRTH2 FSRTH1 CPU S Fuser heater safety circuit F SR CURRM S _ FSRSAFE1 Current Current detection circuit Fus er hea Fuser heater safety circuit