Canon BJ-W9000 Service Manual page 162

Part 4: Technical Reference
c) Components associated with control
The carriage controller interfaces with the head controller and the BJ print heads
through the flexible cables. The flexible cable between the carriage controller and the
head controller is attached to the frame-shaped caterpillar, which moves with the
carriage movement. At the bottom of the rear of the carriage, the photo coupler-type
encoder is mounted that reads the linear scale during carriage movement.
d) Components associated with carriage drive
Vertical/horizontal misalignment of the four BJ print heads and printing-
discrepancies caused the mechanically movement of the two different printing
directions, can be adjusted through the automatic/manual print position
adjustment function.
The carriage motor, driven by DC power, operates the carriage horizontally with the
carriage belt.
The carriage home position, which is also the capping position, is detected by the
home position sensor arm mounted on the right side of the carriage, and the photo
interrupter-type home position sensor installed on the purge unit. The position on
the linear scale that corresponds to the detected carriage home position is recorded
as the home position. Then this home position is set as the reference point for
position control. The carriage motor will operate using the control signals generated
by the motor controller based on the home/reference position.
Caterpillar
Print position sensor
Air buffer
Carriage controller
BJ print head fixing lever
Figure 4-14 Carriage Unit (2)
4-24
Internal temperature
detector
Carriage home
position edge
Media thickness lever
BJ-W9000