Epson Stylus PHOTO 890 Service Manual page 38

EPSON Stylus Photo 890/1280/1290
Figure 2-4 gives the paper feeding mechanism block diagram, showing the parts along
the PF motor drive transmission paths.
Paper Eject Roller
Combination Gear
(13.5, 308)
Spur Gear (76)
PF Motor Pinion Gear
Figure 2-4. Paper Feeding Mechanism
The printer loads paper at the ASF, which is detected by the PE sensor attached to the
right side of the top frame, and advances it to send the paper's leading edge to the
halfway of the front paper guide. Then, to correct paper deflection, the printer feeds the
paper back specified steps toward ASF, and advances the paper again toward the front
paper guide and stops it at the specified TOF (Top Of Form) position. Once printing
starts, the paper is fed by the PF rollers and sub rollers. For printing or transporting the
tailing edge area (14 mm), a notched roller and drive from the paper eject roller are
used. Like the Stylus Photo 870/1270, this printer also provides this extra printable
range of 14 mm from the bottom edge, excluding the bottom margin of 3mm, by
changing the position of the star wheel gear; it has been shifted by 5
the eject roller toward the front paper guide. Due to this change, the tailing edge of
paper is suppressed, and the printer can advance paper steadily. See Figure 2-5 next
page that shows how paper is transported and parts involved.
OPERATING PRINCIPLES
PF Roller
Front Paper Guide
PF Motor
Paper Eject Roller
°
from the top of
[Previous Models]
Notched Roller
Paper
Paper Eject Roller
[Stylus Photo 890/1290]
Figure 2-5. Paper Transportation
Overview
Printhead
Platen Surface
Support Roller
PF Roller
Bottom Margin (3 mm)
°
5
Steady Feeding
Revision C
38