Ricoh Pro C7500 Original Instructions Manual page 23

Leading edge detection mechanism in more detail
This detects the paper edge position (in the direction perpendicular to the paper feed direction) by
scanning the paper path using the contact image sensor (CIS), capturing it as an image when the
paper passes the registration roller and detecting the border between the background and paper
in the image. (Paper alignment is performed based on the detected positional information.)
In the image data scanned by the CIS, the value is low for the background area without paper and
high for the area with paper, so the position exceeding the threshold is detected as the paper
edge.
The value is higher for white paper with high reflectance, and the difference between the
background and the paper portion will be large, making the edge position easily detectable. On
the other hand, for paper with low reflectance (colored paper, black paper, transparencies, etc.),
the value for the paper portion is lower, making it difficult to detect the paper edge.
Optimum setting
When it is better
to increase
the setting value.
Threshold
value
Background
Related Advanced Settings
page 53 "Paper Edge Detection"
Double-feed detection mechanism
The double-feed sensor gauges the thickness of the fed paper. The double-feed sensor detects the
rotation of the paper thickness gauging lever and thus detects a double feed if there is variation in the
thickness of the fed paper.
Related Advanced Settings
page 53 "Detect JAM099"
Sub scan registration mechanism
After the main scan registration is corrected, the sheet passes through the paper transfer timing roller [2]
and then the transfer timing sensor [3] detects the leading edge.
CIS
Paper
Registration gate
Paper edge position
cannot be detected
because the threshold value
is not exceeded.
Paper Delivery
Paper is moved using
information detected by CIS.
M0EBIC1126
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