Epson Stylus Pro 4450 - Paper Eject Phase Sensor; Paper Eject Release Sensor; Paper Eject Switching Movement; Paper Eject Unit

EPSON Stylus Pro 4400/4450/4800/4880/4880C Revision C
Operating Principles Printer Mechanism Components 142
 PG/PO Motor (Stepping motor)
When the transmission path is switched to the Paper Eject Unit side by the
Carriage Unit movement and DE Lock Lever, counterclockwise rotation of
the PG/PO Motor performs eject switching movement as shown below.
(Clockwise rotation does not occur.)
Note : Rotation of the motor in the clockwise direction as seen from the Motor Pinion
Gear is considered "clockwise".
Figure 2-43. Paper Eject Unit
The sensors used in the paper eject mechanism are described below.
 Paper Eject Phase Sensor
This reverse tension switch sensor (mechanical contact) is mounted at the
inner side of the right frame storing the I/H Holder (left). The sensor detects
the condition of the Paper Eject Unit.
 Paper Eject Release Sensor
This reverse tension switch sensor (mechanical contact) is mounted at the
inner side of the left frame storing the I/H Holder (right). When foreign
objects enter the paper path under the Paper Eject Unit and lift the Paper
Eject Unit, the sensor detects this condition and stops printing.
Figure 2-44. Paper Eject Mechanism Sensors
Table 2-12. Paper Eject Switching Movement
Supported Star Wheel Description Supported Media
Phase
Detection
None – Universal roll paper ON (HP)
Roll Paper Star Wheel
Star Wheel weight (10gf)
No ribs
PM roll paper for
photographs, other
specified paper
OFF
Cut Paper Star Wheel
Star Wheel weight (20gf)
Ribs
Universal cut paper OFF
Ribs
Star Wheels
Star Wheels
Paper Eject Phase Sensor
Paper Eject Release Sensor