Epson Stylus Color, Service Manual

Page: 48 / 151

Chapter2 Operating Principles
Rev. A
2-11
2.1.1.3 Paper Feed Mechanism and Pump Mechanism
Mechanisms that send the paper in the hopper to inside the printer and perform constant paper
feed in order to perform printing on the sent paper are called paper feed mechanism as generic name.
In the EPSON Stylus Photo, 4-phase, 200-pole hybrid type pulse motor is used in the PF motor as a
motive power for the paper mechanism and driving is done at 2-2 and 1-2 phase drive method.
This motor is not only used as a power source for paper feed mechanism but also used as power source
for pump mechanism which is necessary for the print head cleaning. By using this pulse motor, it becomes
possible to use high speed drive or intermittent drive for the various paper feeds and pump operations,
such as paper feed, slight paper feed, high and low speed absorption of pump operations. Following
tables(Table 2-7 and 2-8) show PF motor specifications and control method at each mode.
Item Description
Motor type 4-phase/200-pole Stepping motor
Drive voltage
42VDC
±
5%
Coil Resistance
7.8 ohms
±
10%
(per 1 phase under 25
°
C environment)
Drive frequency 400-4320Hz
Control method Bi-Pola Drive
Mode Drive Method Drive Frequency
[Hz]
Pulse Space
(
ƒÊ
s)
Paper feed A 2-2 phase 4320 231
Slight paper feed 1-2 phase 400 2500
Slight paper feed 1-2 phase 2400 417
High speed attraction of pump 2-2 phase 4100 243
Low speed attraction of pump 1-2 phase 1800 555
Low speed paper feed 1-2 phase 1200 833
Paper feed B 2-2 phase 3400 294
Paper feed C 1-2 phase 4000 250
Ordinal absorption of pump 1-2 phase 4100 243
Following tables show 1-2phase drive method at PF motor drive and each drive sequence at 2-2phase
drive method.
Step No. Clockwise Counter clockwise
Phase A Phase B Phase A Phase B
1 +2/3 +2/3 +2/3 +2/3
0 +1 +1 0
2 -2/3 +2/3 +2/3 -2/3
-1 0 0 -1
3 -2/3 -2/3 -2/3 -2/3
0 -1 -1 0
4 +2/3 -2/3 -2/3 +2/3
+1 0 0 +1
Step No. Clockwise(CW) Counter clockwise(CCW)
A B A B
1 +2/3 +2/3 +2/3 +2/3
2 -2/3 +2/3 +2/3 -2/3
3 -2/3 -2/3 -2/3 -2/3
4 +2/3 -2/3 -2/3 +2/3
Table 2-7. PF Motor Specification
Table 2-8. Motor Control Method at Each Mode
Table 2-9. 1-2 Phase Drive Method
Table 2-10. Drive Sequence at 2-2 Phase Drive