Canon BJ-W9000, Service Manual

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e) Components associated with maintenance for the BJ print heads
This printer performs cleaning operations of the BJ print heads by moving the
carriage. Cleaning operations include wiping, maintenance jet, and suction. With
wiping, the four BJ print heads are wiped while the carriage is moving forward at a
constant speed in harmony with the rotation of the blade unit
The maintenance jet cleaning operation is performed in a manner that the BJ print
heads are cleaned by the ejecting action that occurs when the carriage, which is
moving forward at a constant speed, passes through the maintenance jet tray.
The suction cleaning operation is performed by controlling the position of the
carriage in co-ordination with the suction cap and the A-H valve.
f) Components associated with gap adjustment
The media thickness lever located on the right side of the carriage works with the
height adjustment cam. This mechanism controls the height of the carriage by
adjusting the vertical positions of the height adjustment rollers located at the bottom
of the front of the carriage. The vertical position control will change the gap between
the face of the BJ print heads and the paper.
g) Components associated with the print position sensor
The print position sensor mounted on the left side of the carriage consists of an LED
and photosensor. The print position sensor assembly is protected by the sensor
cover except during the detecting operation of the sensor. The sensor cover is opened
or closed by the cover open/close arm of the wiper unit on the basis of the carriage's
position.
h) Components associated with the internal temperature
On the right side of the carriage is located the thermistor which measures the
internal temperature of the printer.
i) Components associated with the carriage home position
The carriage home position represents the position on the linear scale measured
when the carriage home position edge has been detected.
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Part 4: Technical Reference BJ-W9000