Epson 820 All in One Printer User Manual


 
EPSON Stylus PHOTO 810/820/830 Revision B
Operating Principles Overview 37
2.1.5 Ink System Mechanism
The Ink system mechanism consists of Pump mechanism with Carriage lock
mechanism and Capping mechanism with Wiper mechanism. Following table lists
the function for each mechanism.
* Like the previous printers (Stylus COLOR 480/580), this printer adopts the
valveless cap system. The air valve system used for the previous printer
(Stylus COLOR 740) have two functions by the CR position in the capping
condition as follows.
1) Valve closing condition (CL position)
By closing the air valve, the ink is forcibly absorbed from the ink cartridge or
the ink cavity by the Pump unit and is ejected to the Waste drain ink pad while
the CR unit is in the CL position.
2) Valve opening condition (Ink absorption position)
By opening the Air valve, the negative pressure is decreased and only the ink
inside the Cap is ejected while the CR unit is in the further right side than the
CL position. (the ink is not absorbed from the ink cartridge or the ink cavity.)
The following shows you the CR unit position for each condition easily.
But, on the valveless cap system, the above 2) operation is done outside the
capping position. The CR unit moves outside the CR home position and the pump
absorbs the ink inside the Cap.
2.1.5.1 Capping Mechanism
The Capping mechanism covers the Printhead with the Cap to prevent the nozzle from
increasing viscosity when the printer is in stand-by state or when the printer is off.
Unlike the previous printers (Stylus COLOR 480/580), the Cap unit is newly designed
for this printer as follows.
1. Non porous pad in Cap
Due to this, the cap is newly designed as follows.
Figure 2-11. Cap mechanism
The Cap unit used for the previous printers (Stylus COLOR 480/580) has the porous
pad to keep the moisture in the Cap
*1
and prevent that the air bubbles occur in CL
sequence
*2
. The following points are modified to get the same effects on new Cap unit
without the porous pad.
*1 : The diameter of the ink eject hole is smaller than that of Stylus COLOR 480
/580.
*2 : The cap is modified so that the ink flows with air bubbles to the ink eject hole
in the ink absorption sequence more easily.
Table 2-4. Function for each mechanism
Mechanism Function
Capping mechanism *
This is to cover the surface of the Printhead with the cap in
order to
prevent the nozzle from increasing viscosity.
Wiper mechanism
This is to remove the foreign material and unnecessary ink on
the nozzle plate of the Printhead.
Pump mechanism
This is to eject the ink from the ink cartridge, the ink cavity and
the cap to the Waste drain ink pad.
Carriage lock mechanism
This is to lock the CR unit with the Change lever while the CR
unit is at the home position.
For Stylus COLOR 480/580
Porous pad
For Stylus Photo 810/820/830
Ink eject hole
Ink eject hole
CR home position
CL position
(valve closing condition)
Ink absorption position
(valve opening condition)
Printing area