Master Feed - Ricoh JP5000 Service Manual

1 July, 1998

2.4 MASTER FEED

2.4.1 OVERVIEW
[A]
[L]
[K]
[J]
C229D115.WMF
A: Master Edge Sensor
B: Tension Roller
C: Platen Roller
D: Thermal Head
E: Master Set Roller
F: Master Set Sensor
Original scanning starts when an original is set and the Start key is pressed.
Master making begins at the same time. Although master ejecting is done first,
scanning starts very soon after.
The master is a low fiber content paper coated with a thin heat-sensitive film. The
heating elements of the thermal head [D] burn the film to copy the scanned image.
The master is fed while the thermal head develops the image on it. The master
vacuum fans [I] temporarily suck the fed master into the master buffer duct [J]. This
is done because the used master is still being ejected from the drum. When the
drum comes to the master making position, the master is fed to the drum and the
drum master clamper on the drum clamps the master.
The drum then turns to wrap the master around the drum. When the master has
been pulled out of the duct and is pulled tight at the cutter, the cutter [K] cuts the
master.
At the same time as the master is wrapping, a sheet of paper, called the trial print,
is fed. This ensures that ink transfers to the master on the drum, and that there is a
sufficient density of ink for the print run to start. The drum then returns to the home
position and is ready for printing.
[C]
[B]
G: Master Roll
H: Master End Sensor
I: Master Vacuum Fans
J: Master Buffer Duct
K: Cutter
L: Master Feed Control Roller
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[D]
[E]
MASTER FEED
[F]
[G]
[H]
[I]