Epson FX 1170 - B/W Dot-matrix Printer, Service Manual, Page: 45 / 138

REV.-A
Figure 2-1 shows the action of the printer mechanism when a single dot is printed.
Platen
Wire Resetting Spring
Stopper
\ \
Wire
Mask
Paper
Actuating Plate Spring
Figure 2-1. How the Works
The tends to heat up after a period of continuous printing. To minimize the dot wire drive coil
overheating, the head is equipped with a thermistor that can detect the head temperature. When the
thermistor detects changes in the temperature, the voltage signal changes. The CPU detects the
voltage change and stops printing until the head temperature cools.
The is also used asa buzzer. Head driving coils move atafrequency
of 1.5 KHZ for 40 without impacting the platen, so that the wires vibrate. The vibrating dot wires sound like
a buzzer.
2-2