Epson Stylus D120 - Page 30

EPSON Stylus C110/C120/D120 Revision B
OPERATING PRINCIPLE Printer Mechanism Operating Principles 30
2.2.3.2 Paper Feed Mechanism
The major components of the paper feed mechanism are the PF motor, PF roller, EJ
roller, PE sensor, PF encoder sensor, and PF scale. The sheet of paper fed from the
ASF unit is nipped between two rollers to be transported during printing and to be
ejected.
1. The first two rollers used for feeding the paper are the PF roller and the paper
guide roller mounted on the upper paper guide unit. The PF motor drive force is
transmitted to the paper guide roller via the PF roller.
2. The next two rollers are the EJ roller and the star wheel roller mounted on the Star
Wheel Holder Assy. The PF motor drive force is transmitted to the star wheel
roller via the EJ roller.
The figure below shows how the PF motor pinion gear drive force is transmitted to the
PF roller, EJ roller, paper guide roller and the star wheel roller.
When the PF motor pinion gear starts counterclockwise rotation (as seen from the left
side), the sheet of paper fed from the ASF unit to the PF roller is transported and
ejected from the printer by the PF roller/paper guide roller combination and the EJ
roller/star wheel roller combination.
Figure 2-12. Paper Feed Mechanism
Left side
PF Motor
PF Roller
PF Motor Drive Transmission Path (as seen from the left side of the printer)
• PF motor pinion gear (CCW) → Spur gear A (PF roller) (CW) → Transmission gear (CCW) → Spur gear B (EJ roller) (CW)
PF Motor
Pinion Gear
PF Scale
Spur Gear A
(PF Roller)
Spur Gear B
EJ Roller
PF Encoder Sensor
Transmission Gear
Star Wheel Roller
EJ Roller
Paper Guide Roller