Carriage System - Canon iPF8000 series Service Manual

Chapter 2

2.5.3 Carriage system

0012-6495
Linear encoder
Carriage cover sensor
Head relay PCB
Multi sensor
Linear scale
Lift cam sensor
Carriage HP sensor
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Carriage cover sensor
The photointerrupter-based carriage cover sensor detects the opening and closing of the carriage sensor.
When the carriage cover is closed, the sensor light is shielded by the sensor arm, enabling the sensor to detect that the carriage cover is closed.
Carriage HP sensor
The photointerrupter-based carriage HP sensor detects the home position of the carriage.
Installed on the right side plate of the printer, the sensor detects an edge of the carriage home position on the carriage unit under carriage unit under carriage move-
ment control.
The printer establishes the carriage home position from the position at which its edge is detected as a reference position.
Linear encoder sensor
Mounted on the back of the carriage, the linear encoder detects the position of the carriage from a slit in the linear scale during its movement.
Lift cam sensor
A photointerrupter-based sensor. After the sensor light is shielded by the flag, the lift motor is driven by a predetermined number of pulses to regulate the separation
between the printheads and platen automatically.
Ambient temperature sensor
The thermostat-based ambient temperature sensor mounted on the head relay PCB detects the ambient temperature to which the carriage is exposed.
The resistance of the thermistor that varies as a function of temperature changes in the printer is transmitted to the main controller via the carriage relay PCB.
The ambient temperature is used to help calibrate the head temperature sensor and detect abnormal ambient temperatures.
Head temperature sensor
The head temperature sensor detects the temperature of the printhead.
The printhead temperature is transmitted to the main controller via the carriage relay PCB.
The printhead temperature is used to help control the head drive and detect abnormal printhead temperatures.
Printhead contact detection
The printhead contact detects the status of printhead installation by electrical means.
The contact detects the status of contact from voltage changes in the flexible cables on the carriage side that come into contact with two terminals of the printhead
with remote contact surfaces, the power terminals and GND terminal.
Multi sensor
The photo-reflection-type multi sensor is composed of four LEDs (red, blue, green and infrared) and two light-sensitive sensors. It detects the leading edge, skewing,
and width of media and is used for adjustment of the registration, head height, and color calibration.
During head adjustment, the light reflected by the infrared LED and green LED is detected by two light-sensitive sensors to calculate the head height from the
difference between the measurements.
When color calibration is executed, a color chart printed is read with three-color LED (red, blue, green), so color correction is implemented on the basis of the
readings.
Ink mist adhering to the sensor could deliver incorrect measurement readings when color calibration is executed. If the ink dot count exceeds a tolerance, the service
error (E194-4034) would occur. If it does, execute service mode: SERVICE MODE > ADJUST > GAP CALIB. after the multisensor has been replaced to clear
the dot count.
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