Ink System Control; Ink System Basic Functions - Epson Stylus Photo Service Manual

EPSON Stylus Photo

2.3 Ink System Control

In this section, the Ink system to protect the print head and ink supply system and maintain high
printing quality is described here. Ink system control has various kinds combined with several basic
functions. In these kinds of ink control systems, an appropriate sequence is selected according to the
various timers, counters, flags and sensors which are stored in EEPROM. In this section, compositions
of the ink system; basic functions various timers, counters, flags and various ink system sequences,
are described here.

2.3.1 Ink System Basic Functions

Basic functions that consists the ink system is described below.


Wiping
During this operation, the CR moves from left to right to rub the printheads against the rubber
part of the head cleaner (left half of the blade) in the pump unit. This operation is to remove ink, dust
and fuzz adherent to the head surface and to regain normal ink ejection state and ensure firm
capping. A little amount of ink is absorbed to the nozzle surface before Rubbing operation to let the
adhered objects come off easily.


Rubbing
This operation is to rub the printhead surface against the felt part of the head cleaner(right half of the
blade) in the pump unit by shifting the CR from right to left. The purpose of this operation is to remove
unnecessary ink and dust adhered to the head surface after ink absorption in order to regain normal
ink ejection state.


Ink Absorbing Operation
This operation is to absorb ink from the ink cavities by rotating the pump for both black and color
heads with the specified steps while the head surfaces are capped and the air valve is closed. The
purpose of this operation is to eliminate ink which has increased viscosity and bubbles around the
head nozzles.


False Absorbing Operation
This operation removes ink remaining inside the caps by rotating the black and color pumps with
the specified steps while the head surfaces are capped and the air valve is opened. This operation
is accomplished to remove ink from the nozzle plate by vacuuming and ejecting the ink remained after
the ink absorbing operation and flushing operation.


Micro Absorbing
This operation absorbs ink from the ink cavity by rotating the black and color pumps with the specified
steps while the head surfaces are capped and the air valve is opened. The purpose of this operation
is to eject air bubbles formed in the head cavity after ink absorption.


Flushing operation
In this operation, the CR unit moves to false absorption position and discharge specified amount
of ink from the head. The purpose of this position is to prevent ink in the print head nozzle from being
viscosity. There are 3 kinds of flushing as they are listed below.
Type of Flushing
Power Flushing
Normal Flushing (Black)
Normal Flushing (Color)
Flushing at Cleaning (Black)
Flushing at Cleaning (Color)


Micro Vibration
This operation is to add micro vibration to the ink in the head cavity by applying driver voltage and
pulse so that the piezo in the print head is vibrated slightly. The purpose of this operation is to prevent
ink from being viscosity around the head nozzle. This operation is only performed while the CR motor
is accelerating to move the CR for printing operation.
2-28
Table 2-14. Flushing
The Number of Shot
4000 shots
48 shots/per second
36 shots/per second
200 shots
2000 shots
Drive Wave Form
+2V, max.36V to the normal dot optimum
voltage.
Drive waveform of Normal dot
Drive waveform of Normal dot
Drive waveform of Normal dot
Drive waveform of Normal dot
Rev. A