Fusing Roller Pressure/Retraction Mechanism - Konica Minolta bizhub c450 Service Manual

Theory of Operation Ver. 1.0 Mar. 2005
20.3.2

Fusing Roller pressure/retraction mechanism

• To ensure prolonged durability of the Fusing Belt, the Pressure Roller is retracted from
the Fusing Belt during any time other than a print cycle. (The roller is, however, retracted
during a print cycle using envelopes.)
• The Fusing Pressure Roller Pressure/Retraction Motor is turned forward or backward to
press the Pressure Roller up against, and retract it from, the Fusing Belt.
• The Fusing Pressure/Retraction Sensor detects the pressed position of the Pressure
Roller. The retracted position of the Pressure Roller is determined by counting a prede-
termined number of encoder pulses from the pressed position using the Fusing Retrac-
tion Position Sensor.
• In reality, the retracted position is where the Pressure Roller is lightly pressed against the
Fusing Belt.
Pressure Operation
Sector
Gear
• Pressure/Retraction Timing
Power Switch ON
Warm-up
Standby
Copy *1
Power Save mode ON
Heater OFF (cover open, mal-
function, etc.)
*1: Retracted (lightly pressed) condition for envelopes
Pressure
Roller
4036ma2106c0
Conditions
Not retracted position
Heater less than 100 °C
Heater 100 °C or more
At end
–
At start
At end
–
–
20. Fusing section
Retraction Operation
4036ma2107c0
Pressure/Retraction Operation
Pressure → Retraction
Retraction
Retraction → Pressure
Pressure → Retraction
Retraction
Retraction → Pressure
Pressure → Retraction
Retraction
Retraction
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