Canon imageRUNNER ADVANCE C255 Series, Service Manual, Page: 99 / 987

Fixing Film
Pressure Roller
Sensor Flag
Secondary Transfer Outer Roller
ITB
Loop Sensor
(PS11)
M04
DC Controller PCB
(UN04)
Fixing Film
Sensor Flag
Fixing Motor
Arch Sensor
(PS11)
Pressure Roller
Control description
Since the feeding speed of the Pressure Roller and that of the Secondary Transfer Outer Roller are not the same when paper is
fed to the Fixing Assembly, image failure, paper wrinkle, image stretching, etc. occur. To prevent these symptoms, Arch Sensors
located at downstream of the Secondary Transfer Unit detect the slack of paper, and the rotation speed of the Fixing Motor is
adjusted. This keeps an appropriate level of paper slack.
Arch Sensor Control
Control description
This control uses the Arch Sensor (PS11) to detect the paper arch between the transfer nip and fixing nip, and changes the drive
speed of the Fixing Motor as follows to ensure formation of proper arches.
1. When the leading edge of the paper passes through the secondary transfer nip area, the Fixing Motor drive speed is
decelerated, and the decelerated speed is maintained until the leading edge passes through a specified amount.
2. When the Arch Sensor (PS11) detects arches continuously for more than a specified duration, the Fixing Motor drive speed
is accelerated.
When the Arch Sensor (PS11) does not detect arches for more than a specified duration, the Fixing Motor drive speed is
decelerated.
3. The Fixing Motor drive speed is switched based on detection/non-detection of the Arch Sensor (PS11) (the Arch Sensor
{PS11) repeatedly turns ON and OFF).
2. Technology
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