Davin J012, Service Manual

Page: 301 / 365

After the near-end alert, the printer will continue to print with the ink that remains in the partially filled tank
until the printer issues the ink end alert.
Ink Out
A pair of vertical sensor pins [1] is provided for each tank. These pins detect changes in the voltage
differential on the surface of the ink inside the print head tank to detect the presence of air. When these
terminals detect air in the tank, air escapes through the air release valve [2] opened by the air release
solenoid [3]. This allows more ink to enter the tank.
This is a continuous operation. The sensor pin readings signal the ink-out condition when:
• The ink near-end alert has been issued.
• The continued presence of air in the tank indicates that no ink remains in the tank.
As a backup measure, the firmware counts the amount of ink consumed after every near end occurrence.
When this count reaches the value prescribed for the ink cartridge, this will also signal an ink-out condition.
Registration Sensors
6. Detailed Section Descriptions
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