Epson DFX-5000+, Service Manual

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O p e r a t i n g P r i n c i p l e s
2
Overview of Printer Mechanism Operation
This section describes the Model printer mechanism and explains how the
printer works. The Model printer mechanism features a 9-pin, impact dot
printhead for serial printing. The printer mechanism is the main component of
the printer and is supported by the other components (the power supply and
control circuits). Figure 2-l shows the Model
printer mechanism.
Figure 2-l. Model 3Cll Printer Mechanism
The printer mechanism consists following main components:
Printhead
The printhead prints characters (dot matrix patterns) by striking pins (arranged
in a vertical line) against the surface
paper and the ribbon. A character is
printed by repeating this printing operation in the horizontal direction (as the
printhead moves). The printhead includes a head fan and temperature sensor. The
head fan also has a thermistor. When the printhead or fan is too hot, printing
stops until it cools.
(See Thermal Protection, in Chapter 1.)
Carriage mechanism
The carriage mechanism moves the printhead in the horizontal direction. The CR
motor drives the carriage, with the printhead on it. The CR sensor detects the CR
motor speed and carriage position. The CR motor is closed-loop controlled.
Because the CR motor is driven at a very high speed, it includes an isolation
resistance sensor to detect abnormal resistance. The sensor detects an error
resistance is less than
EPSON Service Manual
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