Epson Stylus Color 740 Service Manual

EPSON Stylus COLOR 440, 640, and 740 Chapter 2 Operating Principles
40
2.1.4 Carriage Lock Mechanism
The carria
g
e lock mechanism prevents the printhead from becomin
g
uncapped, which could happen because of vibration durin
g
transport or
mishandlin
g
b
y
users. If the printhead is uncapped for a lon
g
time, ink
on the printhead surface dries out and becomes thick. This can keep
the nozzle from dischar
g
in
g
ink. To prevent this, the printer locks the
carria
g
e under the followin
g
conditions:
 After power-off:
If the power is turned off durin
g
printin
g
or an
y
other operation, the
printer initializes and then locks the carria
g
e in the home position.
 After power-on:
The printer locks the carria
g
e after the power is turned on and
automatic power-on cleanin
g
is completed.
 After ejecting the paper:
If the Load/E
j
ect button is pressed durin
g
printin
g
and no further
data is bein
g
received b
y
the printer, the printer e
j
ects the paper,
locks the carria
g
e, and
g
oes into standb
y
. However, if the
Load/E
j
ect button is pressed for paper loadin
g
onl
y
, the printer does
not perform a carria
g
e lock.
2.1.5 Paper Feed Motor
The paper feed
(
PF
)
motor powers not onl
y
the paper feed mechanism,
but also the pump mechanism that is used for printhead cleanin
g
. The
t
y
pe of motor used is a 4-phase h
y
brid pulse motor. This makes it
possible to use the same motor to perform both hi
g
h- and low-speed
operations for a variet
y
of paper feedin
g
and ink pumpin
g
tasks.
The PF motor for the St
y
lus COLOR 440 and 640 uses 2-2 and 1-2
phase drive methods, whereas the St
y
lus COLOR 740 uses 2W1-2,
W1-2, 1-2 and 2-2 phase drive methods. The followin
g
tables show the
PF motor specifications.
Table 2-5.
PF Motor Specifications (Stylus Color 440, 640)
Table 2-6.
PF Motor Specifications (Stylus Color 740)
Item Description
Motor type 4-phase/48-pole stepper motor
Drive voltage 42 VDC
±
5%
Coil resistance 7 ohms
±
10% (each coil, at 25
°
C)
Drive frequency 100 to 1990 Hz
Control method Bi-polar drive
Item Description
Motor type 4-phase/200-pole stepper motor
Drive voltage 42 VDC
±
5%
Coil resistance 8.8 ohms
±
10% (each coil, at 25
°
C)
Drive frequency 100 to 3240 Hz
Control method Bi-polar drive

Epson Stylus Color 740 Specifications

General

Brand	Epson
Model	Stylus Color 740
Category	Printer
Language	English