Canon LBP-3260 Service Manual page 95

c. Multi-feed prevention mechanism
When feeding from the cassette, the printer uses the separation roller to prevent multi-feeding.
Normally, the separation roller is imparted with a rotational force opposite to that of the feed
roller. However, since the separation roller is equipped with a torque limiter, it rotates with feed
roller 1 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 result
in a weak rotational force being transmitted to the separation roller from feed roller 1.
Consequently, the separation roller's own rotational force separates the extra sheet.
Normal
Muitifeed
Feed roller 1
Pick-up roller
Print paper
Driving force transmitted from the pick-up motor
through the torque limiter.
Figure 2-5-13
Driving force
transmitted from feed
roller 1
Separation roller
CHAPTER 2
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