Canon DR-2580C Service Manual page 35

2. Feed Mechanism
1) Document pickup
The pickup section has a document
stopper. (Figure 2-301)
The stopper opens and starts picking up a
document when a scan start instruction is
given. The carry motor opens and closes
the stopper.
This machine picks up a document by
lowering the pickup roller not by lifting and
lowering the document board.
The lifting and lowering of the pickup roller
synchronizes with the opening and closing
of the stopper.
2) Document separation
Separation of this machine is performed
by the retard roller.
The torque limiter is built in the retard
roller. When the outside pressure on the
roller exceeds the specified value into the
feed direction, the roller begins to rotate in
the same direction.
As shown in Figure 2-302-a, when over-
lapped documents enter into the clear-
ance between the feed roller and the re-
tard roller, the document in contact with
the feed roller is fed in the feed direction,
and the retard roller does not rotate so
that the document in contact with the re-
tard roller is not pushed in.
As shown in Figure 2-302-b, once a single
document remains, the retard roller ro-
tates in conjunction with the feed roller
and the document to feed the document.
If non-separation is selected, the retard
roller rotation becomes free and the
separation function becomes invalid.
COPYRIGHT © 2005 CANON ELECTRONICS INC.
3) Document ejection
CANON DR-2580C FIRST EDITION APR. 2005
CHAPTER 2 FUNCTION & OPERATION
a.
Retard roller
Torque limiter
b.
Figure 2-302
The U-turn path or the straight path can be
selected for the document ejection. The
lever makes the flapper change the feed
path. The flapper is behind the eject roller
1. (Figure 2-301)
The straight path is very useful when the
thicker documents or cards are scanned.
Feed roller
2-9