Paper Feed Mechanism; Table 2-7. Drive Terms; Figure 2-9. Paper Feed Mechanism - Epson Stylus 820 Service Manual

Operating Principles

2.2.4 Paper Feed Mechanism

This printer's paper feed mechanism can feed paper only from the built-in ASF (auto sheet feeder). The paper
feed drive motor is a 2-phase, 96-pole, hybrid-type stepping motor that directly drives the paper feed
mechanism (paper advancing operation, paper pickup operation). This motor also drives the pump
mechanism, but only when the printer is in the cleaning state. The paper feed drive method is driven by only
the 2-2 phase drive method.
Table 2-6. Paper Feed Drive Motor Specification
Item
Motor Type
Drive Voltage
Coil Resistance
Drive Frequency
Excitation Mode
Control Mode
Mode A
Mode B
Mode C
Mode D
Mode E
Mode F
Pickup Trigger
2-10
2-phase, 96-pole, hybrid-type
+42 VDC ± 5%
21 Ω ± 1 Ω
500 ~ 1224 PPS
Open loop:

Table 2-7. Drive Terms

Frequency
Drive Method
(pps)
500 2-2 phase
650 2-2 phase
1224 2-2 phase
1224 2-2 phase
650 2-2 phase
500 2-2 phase
Pickup Roller Clutch
Pickup Roller
Platen
5
Pump / PF Clutch

Figure 2-9. Paper Feed Mechanism

Stylus Color IIs / Stylus 820
Description
2-2 phase
PF (small steps)
PF (color micro weave)
PF
ASF drive
Pump drive
Eliminates backlash
Push the Hopper Edge
Pickup Trigger
Pump On Trigger
1
2
3
4
Purpose
Rev. A