Paper Loading Mechanism; Drive Transmission To The Asf Unit - Epson PH890 Service Manual

EPSON Stylus Photo 890/1290

2.1.4 Paper Loading Mechanism

The paper loading mechanism loads paper at the ASF unit and feeds paper to the PF
rollers. The ASF unit is the same as in previous models. A 4-phase 48-pole PM type
stepping motor is used as the ASF/Pump motor to drive ASF. Drive sent from this
motor is transmitted to the ASF side and Pump side via the disengage mechanism (DE
mechanism). See Figure for the ASF/Pump motor specifications.
Table 2-9. ASF/Pump Motor Specifications
Items
Motor type
Drive method
Drive voltage
Coil Resistance
Inductance
The rotation directions in order to drive ASF unit/ Pump mechanism are as shown
below.
Table 2-10. Directions of ASF Unit/Pump Mechanism Rotation
ASF Paper Loading Roller
Rotation Direction
Rotation Direction
*2
CW Reverse Rotation
*3
CCW Normal Rotation
*1
: Refer to "Drive Transmission to the ASF Unit" on page -41
*2
: CW refers to clockwise from ASF/Pump Motor Pinion side
*3
: CCW refers to counterclockwise from ASF/Pump Motor Pinion side
Drive from the ASF/Pump motor is sent to the ASF unit by the switching operation of
the carriage unit and the DE mechanism described in the following section.
OPERATING PRINCIPLES
Description
4 Phase/ 48-pole /PM type pulse motor
Bipolar constant current drive
+42V +/- 5% (applied to the driver)
10.4 ohm +/- 10%
15.0 ohm +/- 10%
Pump Rotation Direction
Normal Rotation
Reverse Rotation

2.1.4.1 Drive Transmission to the ASF Unit

1) The CR unit moves to the right end of the CR shaft, which then pushes the DE
lock lever to the right end.
2) The ASF/Pump motor rotates counterclockwise specified steps (viewed from the
motor pinion gear side).
3) With the ASF-Pump motor's rotation of step 2), the planetary gear set in the DE
unit shifts toward the combination gear (12, 22.4).
4) The carriage unit moves from the right end of the CR shaft specified steps, which
causes the DE lock lever to fix the planetary gear unit.
5) Torque from the ASF/Pump motor is transmitted as described below.
Motor pinion gear
Combination gear (14, 28)
Figure 2-7 shows the disengage mechanism and its parts.
Combination Gear
14, 28
*1
ASF-Pump Motor Pinion Gear
Figure 2-7. Disengage Mechanism
The ASF unit loads paper by the torque sent from the ASF/Pump motor via the DE
mechanism as described in the following section.
Overview
→ →
Planetary gear (15.2) Combination gear (12, 22.4)
→
Spur gear (32) in ASF
Combination Gear 12, 22.4
Planetary Gear 15.2 Unit
DE Lock Lever
A
Combination Gear 17.19, 25.6
Revision B
→
41