Mechanical Operation; Printing Operation; Print Head - Fujitsu DL7600 Maintenance Manual

5.2 Mechanical Operation

5.2.1 Printing Operation

5.2.1.1 Print head

The print head consists of 24 wires in 12 rows.
The print head has 24 electromagnets that drive armatures with wires.
The print head is fixed to the carriage by the two screws.
When not printing, the armature is parked against the stopper by the elasticity of the coil spring.
During printing, the coil is excited to generate a driving force, which attracts the armature and accordingly moves
the wire in the direction indicate by an arrow.
The wire is guided by the ceramic wire guide and other six plastic guides.
When attracted by the magnet, the armature pushes the wire against the ribbon to print a dot.
When coil excitation is interrupted, the armature returns to the stopper again by the elasticity of the coil spring.
Wire
Ribbon
Wire guide
Guide
Coil
Figure 5.2 Print head structure
139
Coil spring
Armature
9
11
Stopper
13
15
17
PC board
Positions of wire dots
viewed from the printing side
1
2
3
4
5
6
7
8
18
19
20
21
22
23
24
10
12
14
16