Ribbon Feed Motor/External Fan Control - Epson DFX-8000 Service Manual

2.3.7 Ribbon Feed Motor/External Fan Control/Drive Circuit
Figure 2-21 shows a block diagram of the ribbon feed motor control/drive circuit.
The ribbon feed motor is a PM type pulse motor driven with 2-2 phase excitation, which can be driven
in either the forward or reverse direction and stopped at any position. The phase signals output from
two pins are expanded by the predrive circuit, output from four pins, and transmitted to the driver board.
The hold/run signal (RF H/R, which is the common voltage RFCOM switching signal) is output from the
E 0 5 A 1 6 G A .
The drive voltage is a constant 36.5 VDC from the VP3 line.
The common line for the ribbon feed motor is connected to the external fan drive line. Therefore, the
external fan always operates when the ribbon motor operates.
Table 2-20 shows the circuit specifications.
Table 2-20. Ribbon Feed Motor Control/Drive Circuit Specifications
Supply voltage
Current consumption
Drive frequency
Driving method
1
t
/
1
t
I
DATA
BUS
1
1
CPU
1
- - - - — - - - - -- - -- -- - - - -- - - - -- - - - - 4 1- - - - -- - — - -- --- - - - J
MAIN BOARD
Figure 2-21. Ribbon Feed Motor Control/Drive Circuit
Ribbon Feed Motor
3 6 . 5 & 1 VDC
0.10 A (average)
7 2 0 P P S
drive, 2-2 phase excitation
PRE-DRIVE
,
CIRCUIT
Pco
E05A16GA
1
1
t
RFA-D(PHASE)
RF MOTOR
DRIVE
I
CIRCUIT
Q5/1 1/1 6/10/15 :(cOMMON)
#
DRIVER BOARD
2-32
External Fan
3 6 . 5 & 1 VDC
70 mA (average)/90 mA (max.)
o
o
F
Block Diagram
(
(
RF MOTOR
EXTERNAL
FAN