Olivetti DF-650 Service Manual page 111

Punching operation
1. In the punch mode, the paper is fed out to
the finisher. The paper entry motor (PEM)
will be activated in a certain period of time
after the paper entry motor (PEM) is turned
on. The paper entry roller will be rotated.
* Attaching the paper to the paper entry roller
for a certain period of time prevents skewed
feeding.
2. The paper rotated by the paper entry roller is
fed to the punch position and stops at once.
The rotation of the paper entry guide pro-
vides the paper curve.
3. 10 msec before the paper entry roller stops,
the punch motor (PUNM) will be activated to
rotate the punch cam.
The punch cutter descended by the rotation
of the punch cam punches holes on the
paper.
Y104371-8 Service Manual
Paper entry sensor
Paper entry roller
Figure 2-1-36
Paper entry guide
Paper entry roller
Figure 2-1-37
Punch cam
Punch cutter
Figure 2-1-38
3H3
Paper entry
2-1-21