Canon iPF6100 Service Manual page 143

Chapter 2
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
printed
If more than a specified number of non-discharging nozzles have been located in one session of non-discharging
nozzle detection, the normal cleaning sequence is launched before a second session of non-discharging nozzle
detection is conducted. If more than a specified number of non-discharging nozzles are located in the second
session of non-discharging nozzle detection, the normal (High) cleaning session is launched before a third
session of non-discharging nozzle detection is conducted.
If 30 or more non-discharging nozzles and less than 100 non-discharging nozzles per train are located as a result
of the third session of non-discharging nozzle detection, the print operation can resume after the message display
as needed. If 100 or more non-discharging nozzles are located, a head replacement prompt message is
displayed.
Printhead
Nozzle unit
Head management
sensor unit
F-2-49
2-65