Paper Feed/Sheet Feeder Mechanism; Paper Feed/Sheet Feeder Mechanism Functions - Canon QY8-1360-000 Service Manual

Part 4: Technical Reference

3.5 Paper Feed/Sheet Feeder Mechanism

3.5.1 Paper feed/sheet feeder mechanism functions

1) Paper feed function
The paper feed mechanism has two paths: the path taken by sheets fed
automatically from the sheet feeder mechanism and sheets fed manually through
the manual feed slot. The built-in sheet feeder is driven by the paper feed motor,
and loads and automatically feeds the print media. Even envelopes are
automatically fed without the need to operate mechanical paper select levers, etc.
When pages are fed manually, the manually fed page takes precedence over any
media loaded in the sheet feeder.
When the print paper is detected by the paper end sensor (photointerrupter), it is
automatically fed to the top-of-page position on the platen by the paper feed roller.
During printing, the page feed is controlled by controlling the rotation of the paper
feed roller.
On completion of printing, the page is ejected by the paper output roller.
2) Auto platen-head gap adjustment function
The BJC-7100 printer can print without switching the carriage position according to
the thickness of the media being printed on.
The paper feed roller is pressed up by coil springs toward the pressure roller while
the paper output roller is also pressed up by coil springs toward the spurs. The gap
between the head face and the printed media is therefore kept constant regardless of
the thickness of the print media.
Paper Feed Roller
Carriage
Paper Output Roller
Carriage Shaft
Pressure Roller
Spurs
Coil Spring
Paper Output Roller
Spur Cleaner
Paper Output Unit
Figure 4-26 Auto Platen-Head Gap Adjustment
Platen
Paper Feed Roller Bearing
4-36
BJC-7100