Ricoh FW830, Service Manual

Page: 38 / 227

4.3 CROSS MIXING
"Crossmixing" keeps the toner and carrier evenly mixed in the developer and
evenly distributes the developer within the development unit. Crossmixing
also agitates the developer to generate the necessary triboelectric charge on
the toner and carrier particles.
The arrows in the above illustration show the developer movement directions
within the machine. The developer that is attracted to the development roller
[A] is split into two parts by the doctor blade [B]. One part (the magnetic
brush) goes on to develop the latent image on the drum. However, the other
part is trimmed off by the doctor blade and directed to the backspill plate [C].
As the developer slides down the backspill plate to the paddle roller [D], part
of the developer falls into the auger inlets [E] and is transported to the left
side of the unit by the mixing auger [F], where it drops onto the paddle roller.
As the paddle roller rotates, its blades move the developer to the right. The
amount of developer moved to the right by the paddle roller is equal to the
amount moved to the left by the mixing auger.
[C]
[E]
[F]
[A]
[D]
[B]
31 December 1992 DEVELOPMENT
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