Canon LBP1760P, Service Manual

Page: 81 / 394

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.
Figure 2-5-4
2 - 43
CHAPTER 2
Normal
Multi-feed
Paper
Pick-up roller
Feed roller
Separation roller
Driving force transmitted from feed roller
Driving force transmitted from the main motor through the torque limiter