Overview; Operating Principles; Printhead - Epson WF-C5790 Service Manual

EPSON WF-C5790/WF-C5790a/WF-C5710/ET-8700/WF-C5210/WF-C5290/WF-C5290a

3.3 Operating principles

3.3.1 Printhead

3.3.1.1 Overview

WF-C5790/WF-C5790a/WF-C5710/ET-8700/WF-C5210/WF-C5290/WF-C5290a
employs the TFP4 head.
The TFP4 head features dense nozzle pitches (600 dpi); denser than the traditional
heads. In addition, the number of nozzles per row is also greater with the row length of
1.33 inches.
These features contribute to higher image quality and faster printing by increasing both
the quantity and the density of ink droplets per shot.
The following table lists the Printhead specifications.
Table 3-19. Nozzle Configuration
Printhead type
Color
Number of nozzles
Nozzle pitch
Figure 3-19. Printhead Appearance
Configuration and operating principles
TFP4
Black (B: 2 row), Cyan (C: 2 row)
Magenta (M: 2 row), Yellow (Y: 2 row)
3200 nozzles (400 nozzles per row)
0.042 mm (1/600 inch)
The nozzle arrangement of the TFP4 head mounted on this printer differs from that of
the traditional printers. The nozzles of the same color are not arranged next to each
other.
The nozzle layout as seen from behind the Printhead is shown below.
Row A
(Yellow)
Full digit side
This product uses off-carriage type ink supply mechanism. Therefore, the Printhead is
equipped with self-sealing valves
not affected by variation in pressure inside the ink path caused by movements of the
carriage or ink supply operations.
1. This valve opens only when the pressure of the output side drops below a specified value. Because of this
characteristic of the valve, pressure variation in the input side does not affect the output side.
Operating principles
Row B Row D Row F
(Cyan) (Bk) (Magenta)
Row C Row E Row G
(Magenta) (Bk) (Cyan)
Carriage movement direction
Figure 3-20. Nozzle layout
1
so that the amount of ink fired from the Printhead is
Revision A
Row H
(Yellow)
0 digit side
42
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