Ricoh FT5233 Service Manual page 110

12 February 1992 PAPER FEED AND REGISTRATION
[F]
[C]
[A]
[E]
[B]
[D]
The tray bottom plate [A] is also lifted up when the paper tray [B] is set, and
the lead edge of the paper stack is pressed against the paper feed roller [C].
When the feed roller starts turning, it forces the top sheet of the paper stack
across the friction pad [D]. The relay rollers [E] which start turning at the
same time as the feed roller also transport the paper. The feed roller keeps
driving the paper until all but a 50mm trailing edge of paper has passed. Then
the relay rollers take over the paper transport until the paper reaches the
registration rollers [F]. At that time, the paper slightly buckles; and although
the paper feed roller does not have its own driving force (paper feed clutch is
off), the feed roller keeps turning as it is driven by the friction between the
roller and the moving paper. As the trailing edge clears the lead edge of the
paper stack, the feed roller catches the next sheet and starts moving it
forward. The feed roller stops turning when the trailing edge of the first sheet
leaves the feed roller. The leading edge of the next sheet is then held ready
for feeding between the friction pad and feed roller.
Sometime sheets of paper tend to stick together (perhaps due to static
electricity or poorly cut edges). When this happens, two sheets may feed
between the feed roller and friction pad. However, the friction between the
friction pad and the lower sheet is much greater than that between the two
sheets of paper; so, the top sheet slips through while the pad holds the lower
sheet.
The friction pad edge of the paper entrance side is covered by a thin guide
mylar to prevent the lead edge of some paper from being folded by the
friction pad.
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