Brother HL-3450CN Series, Service Manual

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CHAPTER 4 STRUCTURE OF SYSTEM COMPONENTS
4-12
1.4.3 Details of each process
1 Charging
The charging process ensures that the OPC belt is evenly charged by the charger system.
(1) Structure of the charger unit (Refer to Fig.4-8 and Fig.4-11)
i) The charger unit is located as shown in Fig.4-8.
ii) The charger unit consists of the case, corona wire and grid.
iii) The charger unit charges the OPC belt surface to the potential -V
0
(V) with the
corona charge.
iv) The charger unit has the grid controlled to the constant voltage ZD (V) for even
charging.
(2) Process of charging (Refer to Fig.4-12.)
i) The status of the OPC belt surface before charging is -CBV (V).
ii) The charger unit charges the OPC belt surface evenly to -V
0
(V) by generating a
negative charge.
ZD
CBV CHV
Fig. 4-11
-V
0
Fig. 4-12
Charging
Grid
Cleaning
(Blade)
Corona wire
Case