Table 2-6. Pump Mechanism Operation; Figure 2-13. Pump Operation - Epson 4003353 Service Manual

PF Motor Rotational Direction
(forward rotation)
CW
(backward rotation)
The pump draws ink from the printhead nozzles and drains it into the waste ink drain tank. The
printer performs this operation to eliminate dust or bubbles within the nozzles. Figure 2-13
illustrates the pump operation. When the paper feed drive motor rotates CW (forward), the color
pulley pumps in the wheel pump unit rotate in the direction of the arrow while squeezing the ink
tube to push the ink inside the tube out to the waste ink drain tank. When the motor rotates CCW
(backward), the black pulley pumps in the wheel pump unit rotate in the direction of the arrow
while squeezing the ink tube to push the ink inside the tube out to the waste ink drain tank. There
are 2 pump rollers in the pump unit, and the drive power is supplied from the paper feed motor
via the pump drive gear (D/E gear) that is moved by the carriage operation. In the pump unit, the
transmission gear supplies both the black and color pulley, which are rotated by the rotation of the
other.
Vacuuming
Pump Motor (CW) : Color Pumping
No ink draining
\ \
I
No vacuuming
Pump Motor (CW) : Black No Pumping
Rev. A

Table 2-6. Pump Mechanism Operation

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-.. .

Figure 2-13. Pump Operation

I
Operation
Color absorption
Color fail absorption
Wiper reset
Carriage lock reset
Monochrome absorption
Monochrome fail absorption
Wiper set
Carriage lock set
Ink draining
Vacuuming
Pump Motor (CCW) : Black Pumping
No ink draining
No vacuuming
Pump Motor (CCW) : Color No Pumping
Operating Principles
2-11