Epson Stylus Color, Service Manual

Page: 39 / 151

EPSON Stylus Photo
Rev. A
2-2
As you can see major printer mechanisms in the figure 2-1, there are four major mechanisms as they are
listed below.
1) Printing mechanism 2) Carriage drive unit 3) Paper pick up mechanism 4) Pump drive mechanism
2.1.1.1 Printing Mechanism
Basic operating principles of the print head which plays major role of printing mechanism is the same as
previous models; on demand type MACH head method, but there is some differences in the resolution.
(Refer to figure1-1) Also, unlike Stylus Color II, Stylus 820 and Stylus Color 200 automatic correction type,
in order to fix the dispersion of mufti layer piezo electric element which is used for driving each nozzles, it
is necessary to input the VH value written on the side of print head by using exclusive program when you
replace the print head, control board, or the printer mechanism.(However, there are no resistor array to
decide the VH voltage on the main control board.) Following explains the print heads.
PZT
PZT is an abbreviation of Piezo Electric Element. Print signal from C209 board is sent through the
driver board on the print head unit and to the PZT. Then, the PZT pushes the top cavity which has
ink stored, and make the ink discharge from each nozzle located on the nozzle
plate.
Cavity Set
Ink which is absorbed from ink cartridge go through the filter and will be stored temporarily in this
tank, which is called “cavity”, until PZT is driven.
Nozzle Plate
The board with nozzle holes on the printer head 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.
Cartridge needle
Filter
Cavity set
Printhead driver board
PZT
Nozzle Plate
Ink Supply Tube
Ink Cartridge Sensor
Actuator
(Ink Cartridge)
Figure 2-2. Print Head Sectional Drawing