Canon DADF-G1 Service Manual page 28

The registration paper sensor detects the leading and trailing edges of an original, and the
registration clock sensor checks the degree of rotation made by the registration roller while
the original moves past. The DADF controller PCB then converts the degree of rotation into
a length, which is assumed to be the length of the original.
Registration paper sensor
c. Detection in Horizontal Direction
Detection in horizontal direction is performed using the original width detecting variable
resistor (VR). The VR operates in conjunction with the side guide, changing its resistance.
The DADF controller PCB detects the changes in resistance, and converts the result into a
length in horizontal direction.
COPYRIGHT© 2000 CANON INC.
S3
S11
Registration roller
DADF controller PCB
CANON DADF-G1 REV.0 OCT. 2000
CHAPTER 2 OPERATIONS AND TIMING
DADF controller PCB
S1
Registration roller clock sensor
F02-203-03
Side guides
VR
F02-203-04
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