Chapter 6 Principles of Operation
3.1.3 Multiple sheet feed prevention
The sheets set in a tray or a cassette may be stuck together at the edge due to microscope curl-up
along the cutting plane caused by the guillotine, etc. The stuck sheets cause a multiple sheet feed or a
The mechanism for separating these stuck sheets is called "ARRF (Active Retard Roll Feeder)
The sheets are carried by the Paper Feed Roller to the position between the Paper Feed Roller and the
Separator Roller. The Separator Roller is being pushed toward the Paper Feed Roller by a spring
When two sheets are carried concurrently, the top sheet is separated from the bottom sheet by the
friction between the Separator Roller allowing only the top sheet to be fed.
When only one sheet is carried, two kinds of friction are concurrently generated between the Paper
Feed Roller and the sheet (carrying force), and between the Separator Roller and the sheet (retaining
force). However, the friction by the Separator Roller is released because the Separator Roller turns free
by the torque limiter (CLUTCH ASSY FRICTION) provided on its shaft.
The release of the Retard Roll friction allows the sheet to be fed by the Paper Feed Roller.
PAPER FEED ROLLER (Takeaway Roll)
PAPER FEED ROLLER (Feed Roll)
SEPARATOR ROLLER CLUTCH
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