Canon imageFORMULA P-208 Service Manual With Parts Catalog page 29

1) Feed path
The feed path of this machine is a straight
path that is horizontal to the eject roller
including the pickup tray to the reading
section. The pickup roller is not mounted.
The leading edge of the loaded document
is detected by the document sensor and
touches the feed roller and the separation
pad. The document pressure lowers, fol-
lowing the registration roller, and presses
the document against the feed roller. Once
the machine starts scanning, it activates
the rollers to feed the document inside.
The document passes through the regis-
tration roller, the reading units, and the
eject roller and is ejected to the outside of
the machine. This machine does not have
an eject tray.
2) Drive
The feed motor drives the feed roller and
each drive roller. The rotational speed of
the feed motor is determined by scan
conditions.
To provide space between the leading
edge of a document and the trailing edge
of the next document, the drive speed of
the feed roller is slightly lower than the
drive speed of the registration roller and
eject roller. If it is left as it is, the document
is braked when it touches the feed roller
and the registration roller, and therefore, a
one-way clutch is built into the gear used
in the feed roller drive system to follow the
drive speed of the registration roller.
3) Separation
Separation of the documents is performed
by the separation pad. Double feeds and
pickup errors are prevented by optimizing
the shape of the separation pad and fric-
COPYRIGHT © CANON ELECTRONICS INC. 2012
tion against documents.
However, if the document setting method
is incorrect, the contact between the
document and the separation pad be-
comes poor and double feeds or pickup
errors tend to occur easily. For details on
the document setting method, refer to the
user manual or "CHAPTER 1 GENERAL
DESCRIPTION, III. USER OPERATION".
4) Sensor
For document detection, the document
sensor is mounted on the document set-
ting section and the registration sensor is
mounted on the registration roller section.
They are used for feed control and feed
error detection
CANON P-208 FIRST EDITION
CHAPTER 2 FUNCTION & OPERATION
2-9