3-30
Service Manual
4069-XXX
Belt Fuser
The belt fuser utilizes a ceramic heating element inside a
cylindrically formed belt as the heating element of the fusing
process. The contact area of the belt is heated to fusing
temperature. The media passes between the belt and a back-up
roller, fusing the image to the media. The media then passes on
through the decurl rollers to the paper exit.
Unlike the hot roll fuser, the belt fuser does not require detack
fingers to remove the paper from the heated surface (belt). This is
because the contact portion of the belt, which is cylindrically shaped,
gives as the fusing process occurs. This flattens the belt contact
surface. The result is a sharp detack angle between the belt and the
exiting media. This eliminates the need for detack fingers.
The flattening of the belt in combination with the reduced pressure
between the belt and the back-up roller allows the belt fuser to print
on many different types of media without requiring a solenoid
(thumper) to keep the media from wrinkling. A specific type of media
that is affected is an envelope.
The time for the first copy to print is constant for the belt fuser no
matter what state the machine is in, warm or cold. This is a result of
the belt being able to reach fusing temperature very rapidly. This
happens due to the small area that must be heated. The ceramic
slab heats a small portion of the belt that is directly involved in the
fusing process. This is in sharp contrast to the hot roll, which heats
the entire roll to fusing temperature.
