Paper Feed Mechanism; Table 2-3. Paper Feed Motor Specifications - Epson Stylus 1500 Service Manual

Stylus 1500 Service Manual

2.2.4 Paper Feed Mechanism

This printer's paper feed mechanism consists of the built-in ASF (auto sheet feeder), push tractor, PF
(paper feed) motor, front/rear PE (paper end) sensors, PF roller, eject roller unit, and disengage
mechanism. The PF motor is a 4-phase, 48-pole, PM-type stepping motor that directly drives the paper
feed mechanism (for paper advancing and paper pickup). This motor also drives the pump mechanism,
but only when the printer is in the cleaning state. The paper feed mechanism is driven using a 1-2
phase drive method, except in the paper feed drive sequence (W1-2 phase). The paper feed mechanism
is illustrated in Figure 2-6.
The disengage mechanism switches the PF motor torque between the PF drive and pump drive via the
carriage unit stop positions. The PF motor torque is transmitted to the PF roller via the PF motor
pinion, disengage mechanism, and gear train. The torque is then separated for each of the two
directions of the PF roller. One direction of torque transmission is used to drive the paper-ejecting
mechanism via the gear train of the upper paper guide assembly. The other direction is used to drive
the push tractor or ASF mechanism.

Table 2-3. Paper Feed Motor Specifications

Item
Motor type
Drive voltage
Coil resistance
Drive frequency
Excitation mode
Minimum step
Table 2-4. Drive Terms (Paper Feed Mechanism)
Mode
^
Paper loading (ASF)
Paper feed
Pump drive
Pump drive
(lower speed)
Note: Hold current is 0.6 A.
Rev. A
4-phase, 96-pole, HB-type
+42 VDC 5%
10 10%
300 - 2160 Hz
Constant current bipolar drive
Paper feed / pump drive: 2-2 phase, W1-2
phase
1/720" (2-2 phase)
Current Value (A / Phase)
Frequency
Acceleration
(Hz)
W1-2 / 2-2
Phase
2160 0.9 / 0.9
2160 0.9 / 0.9
700 — / 0.9
300 — / —
Operating Principles
Description
Deceleration
Constant W1-2 / 2-2
Phase
0.9 0.75 / 0.75
0.9 0.75 / 0.75
0.9 0.9 / —
0.9 — / —
+
Rush
(before
/ after)
0.6 / 0.6
0.6 / 0.6
0.75 / 0.75
0.75 / 0.75
2-5