Epson Stylus Color 440, Service Manual

Page: 46 / 212

EPSON Stylus Color 440/640/740 Revision A
Chapter 2 Operating Principles 46
2.1.1.2 Printing Process
Following figures show the sectional drawings of normal state and
ejecting state of the printhead.
1. Normal State:
When the print signal is not output, PTZ also does not move in the
waiting state (normal state). (Refer to Figure 2-3.)
2. Ejecting State:
When the print signal is output from the C206 main-B/C255/C256/
C257 main board, IC (IR2C72C:Nozzle Selector) located on the
Print head unit latches the data once by 1-byte unit. Appropriate
PZT latched by nozzle selector is pushed into the cavity by applying
common voltage from the main board. By this operation, ink that is
stored in the cavity pops out from nozzles. (Refer to figure 2-4.)
Figure 2-3. Print Head Normal State
Figure 2-4. Print Head Ejecting State
Nozzle
Nozzle Plate
Cavity
PZT
Ink Course