Epson Scan 2500 Printing Process, Normal State, Ink course Piezo unit Cavity Ejecting State

EPSON Stylus Scan 2500 Revision A

2.2.2 Printing Process

The following figures show sectional drawings of the printhead in the normal and ejecting states.

1.Normal State:

When no print signal is output, the PZT is in the normal, standby, state.

Ink course Piezo unit Cavity

2.Ejecting State:

When a print signal is sent from the MAIN board, the IC (Nozzle Selector) located on the printhead unit receives the data in 1-byte units. The Nozzle Selector then sends the voltage signal on to the appropriate PZT. Due to the physical properties of the PZT, electrical signals cause the PZT to change shape. When the PZT changes shape, it squeezes the ink cavity, ejecting ink out through the nozzles.

Nozzles	Nozzle plate
	surface

Figure 2-4. Printhead Ejecting State

Figure 2-3. Printhead Normal State

Operating Principles Printer Mechanism Operation 37