Chapter 2
2-45
Pump encoder sensor
The photointerrupter-based sensor reads slits in the encoder film of the purge motor and controls the amount of
its rotation accordingly.
F-2-34
Valve open/closed detection sensor
The photointerrupter-based valve open/closed detection sensor detects the status of the valve cam.
The sensor detects that the ink supply valve is open when the sensor light is shielded by a link interlocked with
the valve cam.
Ink detection sensor
The ink detection sensor detects the presence or absence of the ink in an ink tank with respect to the status of
continuity between two hollow needles.
When the ink level in the tank falls to a point below the wall surrounding the hollow needles in the air passage,
continuity with the hollow needle on the ink supply side is disrupted, causing the sensor to detect that is ink is
out.
F-2-35
Head management sensor
The photo-transmission-type sensor detects that the printhead is discharging ink.
The carriage moves to and stops at the detection positions for individual nozzle arrays. When the carriage is at
a stop, nozzles discharge ink on after another.
The sensor detects each nozzle due to the voltage change caused when ink discharged from the nozzle blocks
the sensor light.
Non-discharging nozzle detection is carried out at the following timings:
- After the execution of Cleaning 1, Cleaning 2, Cleaning 3, Cleaning 6 or Cleaning 10
- After the number of copies that has been set by the user menu choice Nozzle Check Frequency have been
Sensor
Slits
Ink tank
Wall
Rubber plug
Needle(air passage)
Needle (ink supply)