2.2.1 Printing Mechanism
The basic principles of the printhead are the same as previous models; Drop-On-
Demand type MACH head method.
Also, unlike Stylus Color IIs, 820, and 200, the Stylus Scan does not have the
automatic-correction feature. Therefore, you need to manually input the drive-voltage
code (printed on top of the printhead) for the multi-layer piezo electric element. Input
this value every time you replace the printhead, control board, or printer mechanism.
(Note there is no resistor array to decide the VH voltage on the main control board.)
The main parts of the printhead and carriage are described below.
o PZT
PZT is an abbreviation of Piezo Electric Element. The print signal is sent from the
PSB/PSE board through the driver board on the printhead unit and to the PZT.
Then, the appropriate PZT pushes squeezes the cavity, forcing the ink stored in the
cavity out through the nozzle. This process is described in more detail on the next
page.
o Ink cavity
Ink flows from the ink cartridge, through the filter, and to the ink cavity where it is
stored until one of the PZT units forces it out through the nozzles.
o Nozzle Plate
The bottom surface of the printhead which contains nozzle holes to direct ejected
ink toward the paper below. See the next page.
o Filter
When the ink cartridge is installed, if any dirt or dust around the cartridge needles
is absorbed into the inside of the printhead, there is a large possibility that the
nozzles will clog. Clogged nozzles can be detected by alignment failure and dot-
missing problems. To prevent these kinds of problems, a filter is set below the
cartridge needle and ink flows through the filter on its way to the ink cavity.
Figure 2-2. Printhead Sectional Drawing
o I/C Out sensor actuator
The I/C Out sensor detects whether or not an ink cartridge is installed according to
the position of the I/C Out sensor actuator. When a cartridge is installed, the
actuator is pushed down, which turns the shaft that is connected to the actuator.
The flag at the other end of the shaft activates the I/C Out sensor when the
cartridge is fully in place.
See the next page for more details on the nozzle selector board and the ink ejecting
process.
Nozzle selector
Board
I/C Out sensor
actuator
Needle
Ink cartridge
Filter
PZT (Piezo)
unit
Ink cavity
Nozzle
plate
To Next Page
Loading...
Need help?
General
