Canon image Prograf iPF780 Series, Service Manual

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Chapter 2
2-15
F-2-12
f) Carriage height adjustment unit
The head height is adjusted with the carriage halted at its home position.
The lift motor is driven to rotate the carriage height changing cam within the carriage, in sync with which the lift cams on both sides of the carriage move the head
holder up and down, thereby varying the separation between the face of the printhead and the paper.
The printhead height is detected from the lift cam sensor within the carriage and the distance of rotation of the lift motor.
g) Slant adjustment unit
The tilting of the head is adjusted with the slant adjustment lever.
The point where the slant adjustment lever axis touches the head holder is offset from the fulcrum of the lever axis. Therefore, the printhead is tilted by moving the
slant adjustment lever and moving the position on the right side of the head holder back or forward.
F-2-13
h) Multi Sensor
A photo reflective type multi sensor consists of three red LEDs, one red/blue/green LED array, and three light receiving sensors and is used for media end, skew,
and width adjustment, registration adjustment, head height adjustment, and print position adjustment.
The multi sensor reference has three white plates attached to it, so that a reference value can be calculated during carriage height measurement by measuring the
intensity of light reflected upon the white plates.
(Service mode: SERVICE MODE>ADJUST>GAP CALIB.)
i) Shaft cleaner units
The shaft cleaners mounted at the left and right of the carriage are used to clean the carriage and apply oil to the shaft.
Carriage
Spring (for Printhead Height)
Spring (for Printhead Slant)
Head Holder
Lift Motor
Lift Cam Sensor
Carriage Height Changing Cam
Slant Adjustment Lever
Spring (for Printhead Slant)
Slant Adjustment Lever Shaft
Linear Encoder Sensor
Lift Cam Sensor
Linear Scale
Lift Drive Unit
Multi Sensor Reference
Head Management Sensor
Shaft Cleaner
Shaft Cleaner
Multi Sensor
Carriage PCB