Paper Cooling - Ricoh B234 Service Manual

FUSING
6.16.6

PAPER COOLING

[A]
[C]
[F]
[B]
B234D987.WMF
[D]
[E]
B234D988.WMF
The paper cooling pipe [A] cools the copy paper [B] after it has gone through the
fusing unit. This prevents the temperature around the drum from increasing in
duplex mode.
The paper cooling pipe has a hollow metal tube inside. Water capillary tubes run
along the inside of the paper cooling pipe, and these transfer heat within the pipe.
The hot paper leaving the fusing unit heats the parts of the cooling pipe that it
touches at [C] (black arrows), causing the water in the pipe to vaporize. This
creates a high-speed flow of steam to the ends of the pipe, which are cooler,
especially to the rear, which is well away from the paper feed path, and has the
cooling fins [D] attached to it. When the steam reaches this area, it cools and
condenses. Capillary action returns the condensation to the heated part of the pipe.
This heat transfer cycle (vaporization → steam transfer → condensation) repeats
continuously. Paper cooling pipe fan 1 [E] in the duct at the machine rear side
cools the fins and paper cooling fan 2 [F] pulls the air around the fins out of the
fusing unit.
B234/B235/B236/D101/D102/D103 6-162 SM