Epson Stylus Color 640 Service Manual page 54

EPSON Stylus Color 440/640/740
The table below shows PF/Pump motor rotational direction and pump
system operation.
Table 2-7.
Relationship between Pump Motor Rotation and it's Work
PF/Pump motor rotational direction
Clockwise (CW)
forward rotation
Counterclockwise (CCW)
backward rotation
Refer to Figure 1-13 in the right column which shows the pump
operations at clockwise and counterclockwise rotation.
In the ink absorptive operation such as cleaning, flushing and initial ink
charge except for printing operation, ink in the ink cartridge drains to the
waste ink absorber(pad) through the cap by the pump unit drive. In case
of printing and flashing drive, ink is popped out by the PZT in the print
head, but in case of absorptive operation such as cleaning and initial ink
charge, ink absorption is performed only by the pump drive without PZT
drive after the head surface is adhered to the cap. The next page
explains cap mechanism and relation between printer operation and
cap.
Chapter 2 Operating Principles
Pump unit operation
1)Release from the Pump pressure welding
2)Head cleaner reset
3)Carriage lock reset
1)Rotation towards pump pressure welding
2)Head cleaner set
3)Carriage lock set
CW Rotation
Tube pressured
Figure 2-13. Pump Roller Rotation and it's Operation
Revision A
CCW Rotation
Tube released
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