Canon iPF825, Service Manual

Page: 90 / 316

Chapter 2
2-20
2.3.2.2 Ink Tank Unit
2.3.2.2.1 Structure of Ink Tank Unit
0020-5487
a) Ink tanks
The ink level in each ink tank is memorized in EEPROM attached to the tank and is detected as a dot count on the basis of the EEPROM information.
When an electrode attached to a hollow needle detects no continuity, it displays a message reporting that the ink tank is nearly empty.
If the dot count reaches a predesigned value in this state, an ink out condition is assumed.
b) Ink port
Depressing the ink tank fixer lever on the printer would cause would cause a hollow needle to pierce the ink tank port sealed by a rubber plug, linking the ink passage
of the ink to the printer.
c) Air passage
Depressing the ink tank fixer lever on the printer would cause an open hollow needle to pierce the air passage sealed by a rubber plug releasing the internal pressure
of the ink tank to keep it constant.
d) Notches for preventing incorrect installation
Ink tanks are furnished with a notch for preventing incorrect installation.
If the installation of an ink tank in incorrect position is attempted, the notch would interfere with it, preventing its installation.
The ink tank fixer lever won't lower without the ink tank fully inserted to reach the mounting position, so the ink cannot be supplied.
F-2-9
Ink tank
Ink port
Air passage
Notch for preventing incorrect installation
EEPROM
Notch for preventing
incorrect installation