Printing Mechanism - Epson Stylus COLOR 800 Service Manual

EPSON Stylus &2/25 800

2.2.2 Printing Mechanism

The printing method used for this printer is On-demand ink jet system, same as for other EPSON ink jet
printers. This printer, however, uses newly designed MACH Head, which ensures a high level of printing
quality at a higher speed. This printer is equipped with separate printheads of the same type; one for black
and one for each of the three colors (magenta, cyan, and yellow). Quick penetration, the type of black and
color ink, is also improved for this printer, which enables the users to have the printing image in the high
quality on the normal paper.
‰ Printhead
The black and color printheads for this printer use the newly designed MACH Head (E-CHIPS Head).
The structure of the printhead is the same as for previous CHIPS Head except for the nozzle
configuration. The Black Head for this printer has 128 nozzles (32 nozzles for each of 4 rows ) which
is as twice as many as previous EPSON ink jet printers, and the Color Head has 192 nozzles (32
nozzles for each of 6 rows) which is 3 times as many as previous EPSON ink jet printers. Therefore
printing quality as well as the speed for this printer is higher than ever. The nozzle structure for this
printhead is shown in the figure below.
„PZT
PZT is an abbreviation of the Piezo Electric Element. Print signal from C202 MAIN board is sent
through the driver board on the Printhead unit and to the PZT. Then, the PZT pushes the top cavity
which has ink stored, and makes the ink discharge from each nozzle located on the nozzle plate.
„Cavity Set
Ink which is absorbed from ink cartridge goes through the filter and will be stored temporarily in
this tank, which is called "cavity" unit driven by PZT.
„Nozzle Plate
The board with nozzle holes on the Printhead surface is called Nozzle Plate.
„Filter
When the ink cartridge is installed, if any dirt or dust around the cartridge needles are absorbed
into the head inside, there is a great possibility of causing nozzle clog and disturbance of ink flow
and finally causing alignment failure and dot-missing. In order to prevent this, filter is set at
cartridge needle below and ink is once filtered here.
2-2
Download Service Manual and Resetter Printer at http://printer1.blogspot.com
Figure 2-2. Printhead Structure
Rev. A