Chapter 5 Principles Of Operation; Mechanical Operation; Printing Operation - Fujitsu ULTIMA90 Maintenance Manual

CHAPTER 5 PRINCIPLES OF OPERATION

5.1 Overview
This section explains the principles of DL7600 operation. A microprocessor controls the following basic
functions:
Carriage drive
Print head drive
Paper feed

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.
Figure 5.1 Function sequence
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