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MX-4101N FUSER SECTION M – 2
2. Operational descriptions
A. Fusing unit drive
For driving the fusing unit, the drive power is transmitted from the
drive motor (FUM) through the connection gear to the upper heat
roller gear.
Driving by the drive motor (stepping motor) is performed according
to the control signal sent from the PCU.
drive motor (FUM) through the connection gear to the upper heat
roller gear.
Driving by the drive motor (stepping motor) is performed according
to the control signal sent from the PCU.
B. Heater lamp drive
The surface temperature of the heat roller detected by the ther-
mistor is sent to the PCU. When the temperature is lower than the
specified level, the heater lamp ON signal is sent from the PCU to
the heater lamp drive circuit on the HL PWB.
The power triac in the heater lamp drive circuit is turned on, and the
AC power is supplied to the heater lamp, lighting the lamp and
heating the heat roller.
To prepare for an abnormally high temperature of the heat roller,
the thermostat is provided for safety.
When the thermostat is opened, the power supply (AC line) to the
heater lamp is cut off.
mistor is sent to the PCU. When the temperature is lower than the
specified level, the heater lamp ON signal is sent from the PCU to
the heater lamp drive circuit on the HL PWB.
The power triac in the heater lamp drive circuit is turned on, and the
AC power is supplied to the heater lamp, lighting the lamp and
heating the heat roller.
To prepare for an abnormally high temperature of the heat roller,
the thermostat is provided for safety.
When the thermostat is opened, the power supply (AC line) to the
heater lamp is cut off.
C. Fusing operation
Color toner (Y,M,C,K) on paper is subject to heat and pressure to
be fused on paper.
At that time, color toner of Y, M, C, and K are mixed to reproduce
colors approximate to the document image colors.
The heater lamps are provided in the lower and the upper heat
roller to heat paper from the upper and the lower sides.
This is because paper must be heated both from the upper side
and from the lower side together in order to melt and fuse toner in
the four layers on the paper.
The upper and the lower heat rollers of silicon rubber are
employed.
This is because of the following reasons.
be fused on paper.
At that time, color toner of Y, M, C, and K are mixed to reproduce
colors approximate to the document image colors.
The heater lamps are provided in the lower and the upper heat
roller to heat paper from the upper and the lower sides.
This is because paper must be heated both from the upper side
and from the lower side together in order to melt and fuse toner in
the four layers on the paper.
The upper and the lower heat rollers of silicon rubber are
employed.
This is because of the following reasons.
1)
To increase the nip quantity. To increase the heating capacity
for paper.
for paper.
2)
By pressing the flexible roller, multi-layer toner can be fused
without deformation.
without deformation.
3)
An even pressure can be applied to rough surface of toner lay-
ers (multi-layer structure).
ers (multi-layer structure).
Signal name
Name
Function/Operation
FUM
Fusing motor
Drives the fusing unit.
HL_LM
Heater lamp lower main
Heats the fusing roller (pressing).
HL_UM
Heater lamp upper main
Heats the fusing roller (heating).
HL_EX1
Heater lamp external 1
Heats the fusing roller (heating). (External)
HL_EX2
Heater lamp external 2
Heats the fusing roller (heating). (External)
HLPCD
Fusing pressure release sensor Detects pressure release of the fusing roller.
TS MAIN
Thermostat (1)
Shuts conduction to the heater lamp when the temperature rises abnormally. [For the fusing roller (heating)]
TS EX1
Thermostat (2)
Shuts conduction to the heater lamp when the temperature rises abnormally. [For the fusing roller (heating)]
(External)
(External)
TS EX2
Thermostat (3)
When the temperature rises abnormally, conduction to the heater lamp is cut off.
[For the fusing roller (heating)] (External)
[For the fusing roller (heating)] (External)
TS SUB
Thermostat (4)
When the temperature rises abnormally, conduction to the heater lamp is cut off.
[For the fusing roller (pressing)] (External)
[For the fusing roller (pressing)] (External)
PRM
Fusing pressure release motor
Adjusts the fusing roller pressure.
TH_UM
Fusing temperature sensor (1)
Detects the surface temperature of the fusing roller (heating). (Center section)
TH_US
Fusing temperature sensor (2)
Detects the surface temperature of the fusing roller (heating). (Edge section)
TH_LM
Fusing temperature sensor (3)
Detects the surface temperature of the fusing roller (pressing).
TH_EX1
Fusing temperature sensor (4)
Detects the surface temperature of the heat roller (external).
TH_EX2
Fusing temperature sensor (5)
Detects the surface temperature of the heat roller (external).
No.
Name
Function/Operation
1
Fusing roller (Heating)
Applies heat and pressure to toner on paper to fuse it on paper.
2
Upper separation pawl
Mechanically separates paper which was not naturally separated from the fusing roller (heating).
3
Fusing roller (Pressing)
Applies heat and pressure to toner on paper to fuse it on paper.
4
Transport roller 9 (Drive)
Transports paper from the fusing roller to the paper exit roller 1.
5
Web roller
Cleans the upper heat roller.
6
Lower separation pawl
Mechanically separates paper which was not naturally separated from the fusing roller (pressing).
FUM
PCU
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