Printer Mechanism; Printhead - Epson DFX-9000 Service Manual

Epson DFX-9000

2.2 Printer mechanism

The operating principles of the printer mechanism are described below,
and includes the following sections:
2.2.1 Printhead (p.58)
2.2.2 Carrier drive mechanism (p.61)
2.2.3 Ribbon drive mechanism (p.63)
2.2.4 Paper feed mechanism (p.64)
2.2.4.1 Tractor mechanism (p.64)
2.2.4.4 Paper path switching mechanism (p.69)
2.2.4.5 Paper eject mechanism (p.70)
2.2.5 Automatic Paper Thickness Control (APTC) mechanism (p.72)
2.2.6 Other mechanisms (p.75)
2.2.6.1 Top cover open/close detection mechanism (p.75)
2.2.6.2 Cooling fans (p.76)
Operating Principles

2.2.1 Printhead

The printhead contains 36 coils that drive armatures to which the print
wires are attached.
When not firing, the armatures are pushed back to the stopper by coil
springs. When the coil is energized, the armatures, attracted by the
magnetic field, move the print wires in the direction of the red arrow
below in Figure 2-2. The print wires, guided by the wire guides through
the front of the printhead, strike the ribbon and then the print media
behind the ribbon. When the coil current is switched off, the armatures
are pushed back to the stopper again by the coil springs and enter the
print-waiting state.
Stoppers
Wires
Wire Guides
Guides
Figure 2-2. The Print Head Structure
Printer mechanism
Armatures Coils
Coil Springs
Revision B
58