Developing Process; Transferring Process; Cleaning The Transfer Roller - Brother IntelliFax-4750 Service Manual

(3) Developing process

The developing process develops an electrostatic latent image formed on the drum in the
exposing process, into a toner image.
The developer roller attracts the toner particles fed from the toner cartridge by the toner supply
roller, and then conveys them to the contact section with the laser-sensitive drum
On the contact section between the developer roller and drum, the positive toner particles stick to
the neutralized spots on the drum according to the principles of attraction and repulsion,
transforming a latent image into a toner image.
The agitator (which agitate toner particles in the chamber) and the blade allow toner particles to be
fed onto the developer roller at an even thickness.

(4) Transferring process

When a paper passes between the drum and the transfer roller, the controller negatively charges
the transfer roller. The toner is positive, so the toner image formed on the drum will be transferred
onto the paper according to the same principle as for the developing process.

Cleaning the transfer roller

In the transferring process, the transfer roller may be contaminated with toner since not all the
toner particles on the drum are transferred onto the paper but some toner particles will remain on
the drum and will be transferred from the drum to the transfer roller. If paper jam or other errors
occur, the toner image fails to stick to the paper and will stick to the transfer roller.
To repulse this toner, the controller positively charges the transfer roller. The toner returns from
the transfer roller to the drum. During non-printing rotation of the drum, the toner particles on the
drum will be returned to the chamber through the developer roller.
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