Paper Feed Mechanism - Epson Stylus COLOR 1520 Service Manual

EPSON Stylus COLOR 1520

2.2.4 Paper Feed Mechanism

The paper feed mechanism of this printer consists of the integrated ASF (Auto Sheet Feeder)
mechanism, tractor mechanism, PF (Paper Feed) motor, front/rear PE (Paper End) sensors, PF roller,
paper guide mechanism, paper eject unit, and PF motor drive disengage mechanism. The torque from
the PF motor drives the paper load mechanism, paper feed mechanism and paper eject mechanism.
While the printer is not printing, the PF motor drive disengage mechanism switches the torque from the
PF motor to the pump mechanism, which depends on the CR position. While the paper feed mechanism
is driven, the torque from the PF motor is transmitted via PF motor pinion gear and disengage gear to
the PF roller., where the torque is then divided into 2 directions. One is transmitted to the paper eject
mechanism via the gear train in the paper guide assembly. The other is transmitted to the ASF
mechanism via the transmission gear.
The tractor drive gear train is set at the left end of the PF roller. Table 2-4 and Table 2-5 shows the
specification for the PF motor and PF motor drive terms, respectively. Figure 2-5 illustrates the paper
feed mechanism.
Item
Motor type
Drive voltage
Coil resistance
Connection
Excitation mode
Minimum step
Operation
mode
Paper feed
(Line feed:6/1 inch)
ASF Feed
Pump driven
Pump driven
(slow)
Note) Double 1-2 phase drive / 2-2 phase drive
Paper Eject Roller Unit
2-6
Table 2-4 PF Motor Specification
4-phases / 96-pole / HB type stepping motor

42 VDC 5% (The voltage applied to the driver)
 
10 10% (at 25
Bipolar
2-2 phase, 1-2 phase, W1-2 phase constant current drive
1/720 inch / step (2-2 phase drive)
Table 2-5 PF Motor Drive Terms
Acceleration
0.9/0.9
0.9/0.9

/0.9
 
/
Tractor Disengage Gear
PF Motor Pinion Gear
Disengage Gear
To the tractor
mechanism.
To the ASF
mechanism.
ASF
Transmission Gear
PF Drive Roller
Paper Eject Roller Shaft
Figure 2-5. Paper Feeding Mechanism
Description

C per 1 phase)
Constant Deceleration
0.9 0.75/0.75
0.9 0.75/0.75
0.9
0.9
PF Motor
Paper Eject Roller Shaft
Stand-by
0.6
0.6
0.9 0.6
 
0.6
/
Pump Mechanism
Rev. A