Paper Registration Sequence; Punch Unit Driving Sequence - Lexmark C920 Service Manual

5056-XXX

Paper registration sequence

Paper is stopped at the hole punching position momentarily before the paper standstill clutch turns ON and
changes to open. At this point, the driving force cannot be transmitted to the register rollers. The paper then
stops at register rollers, and since the finisher keeps feeding the paper from the host printer, the leading edge of
the paper stops at the register rollers. The paper buckles at the entrance. The paper buckle feeds downward to
the lower entrance paper guide, where it is hole-punched at the leading edge. The paper standstill clutch turns
OFF and changes to close as the driving force transmits to register rollers, and the paper transportation restarts.

Punch unit driving sequence

When the paper feed motor drives, the driving force is transmitted through the punch unit drive gear to the clutch
gears of the punch unit. Since the punch clutch is normally opened OFF, the driving force is not transmitted to
the driving shaft. When the punch clutch turns ON, it is closed and unlocked. The driving force is then
transmitted from the clutch gears to the driving shaft. As the shaft turns, the rotation of the cam causes the paper
to be hole-punched. Immediately after one turn of the shaft, the punch clutch turns OFF, and the drive shaft
stops.
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Service Manual
Cover
Paper
Entrance
Sensor
Registration
Roller
Drive
Shaft
Cover
Cam
Punch
Clutch
Registration
Idler Roller
Registration
Clutch
Blade