Canon LBP-1760 Service Manual page 81

b. Multi-feed prevention mechanism
When picking up the paper from the cassette, the printer uses the separation roller to prevent
multi-feeding. Normally, the separation roller is imparted with a rotational force in the same
direction as that of the feed roller. However, since the separation roller is equipped with a torque
limiter, it rotates with feed roller by transmission of its rotational force via the transported paper.
On the other hand, if multiple sheets of paper are picked up, the low friction force between the
sheets of paper results in a weak rotational force being transmitted to the separation roller from
feed roller. Consequently, the separation roller's own rotational force separates the extra sheet.
Paper
Normal
Multi-feed
Feed roller
Pick-up roller
Driving force transmitted from the main motor through the torque limiter
Figure 2-5-4
Driving force transmitted from feed roller
Separation roller
CHAPTER 2
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