Canon CLBR 460ps Service Manual page 137

b. Multi-feed prevention mechanism
For cassette pick-up, this printer uses a separation roller to prevent simultaneous feeding of sev-
eral sheets. Normally, the separation roller is imparted with rotational force reverse to the feed
roller which rotates in the direction of paper feed. However, as the separation roller has a torque
limiter, it rotates with feed roller 1 through transmission of its rotational force via the trans-
ported paper. On the other hand, if multiple sheets are picked up, the low friction between these
sheets results in a weak rotational force being transmitted to the separation roller from the feed
roller. As a result, the separation roller's own rotational force separates the extra sheets.
Normal
Multiple feeding
Cassette feed roller
Pick-up roller
Paper
Rotational force transmitted from the
pick-up motor via torque limiter
Figure 2-5-3
CHAPTER 2
Rotational force transmitted
from the cassette feed roller
Separation roller
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