Fuser temperature control

The fuser temperature control maintains the target surface temperature of the fuser sleeve.

Figure 1-7Fuser temperature-control circuit

Fuser

Low-voltage power supply

 

 

Fuse

 

Zerocross

/ZEROX

 

 

 

 

 

 

 

 

 

 

 

 

circuit

 

 

Fuser sleeve unit

 

 

 

 

FSRD1

 

 

 

 

 

 

 

 

 

Fuser heater

 

Relay

Relay

/RLD

 

 

 

control circuit

 

 

 

 

TH1

 

 

 

 

control

 

 

 

 

 

 

circuit

 

 

TH2

 

 

 

 

 

 

TP1

 

 

 

 

 

 

TH3

 

 

 

 

 

CPU

 

 

 

 

 

 

H1

 

Current

 

 

Relay

 

 

 

 

 

 

 

 

 

 

detection

 

 

 

 

 

 

 

 

 

FSR_CURRMS

Pressure

 

circuit

 

 

 

 

 

 

 

 

 

 

roller

 

 

Fuser heater safety circuit

FSRSAFE1

 

 

 

 

 

 

 

 

H1: Fuser heater

Fuser heater safety circuit

 

FSRSAFE2

 

TP1:Thermoswitch

 

 

 

 

 

 

 

Fuser control circuit

 

TH1: Main thermistor

 

 

Fuser heater

 

 

 

 

/FSRNEW

TH2: Sub thermistor 1

 

 

 

 

safety circuit

TH3: Sub thermistor 2

 

 

 

 

/FSRSNS

 

 

 

 

 

 

 

FSRTH3

 

 

 

 

 

 

 

FSRTH2

 

 

 

 

 

 

 

FSRTH1

 

 

 

 

 

 

 

 

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

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Image 47
HP Enterprise CC490A manual Fuser temperature control, Fuser sleeve temperature protection