Brother DCP-7030 Service Manual page 59

(4) Transfer
By applying a minus charge to the transfer roller, the toner adhered to the exposured drum is
transferred to the paper.
Supply roller Develop roller Exposure drum
Toner cartridge Transfer roller Toner
Fig. Ref. 2-24
Memo :
Control of transfer bias
The transfer bias applied in the transfer roller is adjusted according to types and sizes of
paper so as to keep excellent image quality.
Ref. 2-24
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