Ribbon Feed Motor Drive Circuit - Epson DFX-8500 Service Manual

DFX-8500

RIBBON FEED MOTOR DRIVE CIRCUIT

Figure 2-24 shows a block diagram of the ribbon feed motor drive circuit, and Table 2-10 provides the ribbon
feed motor specifications. The ribbon feed motor is a stepping motor. The control circuit performs open-loop
phase switching control according to the timing data for acceleration, constant speed, and deceleration.
CPU ports PG10 to PG13 output the motor phase switching signals. The control method is not equipped with
a hold circuit for changing the motor phase. The ribbon feed motor rotates when the carriage moves.
Specification
Form
Supply Voltage
Internal Coil Resistance
Frequency
Current Consumption
Driving Method
E05B36
(IC1)
RFCOM
TMP95C061A
(IC2)
Figure 2-24. Ribbon Feed Motor Drive Circuit Block Diagram
2-34
Table 2-10. Ribbon Feed Motor Specifications
DRV
Main
Board
Board
PG10
PG11
PG12
PG13
Description
4-phase, 48-pole, PM pulse motor
37 VDC (applied to the drive circuit)
150 ohms + 10 % per phase at 25
720 pps
Driving: 0.10 A (average)
Constant voltage driving, 2-2 phase drive
VP 3
F1
Q20,Q21
Q22
Q23
Q24
Q25
PNP Transistor x4
o
C
RF COM
RF A
RF Motor
RF B
RF C
RF D