Brother International HL-3400CN Service Manual - Page 62

HL-3400CN

SERVICE

MANUAL

(2)

Variation

of

OPC

Belt

Potential

(See

Fig.4-10.)

i)

The

OPC

belt

is

initially

biased

to

-CBV(V).

ii)

The

OPC

belt

surface

is

evenly

charged

to

V

o

(V)

in

the

charging

process.

iii)

The

potential

of

the

exposure

part

of

the

OPC

belt

is

reduced

to

-VR(V)

as

it

is

exposed

to

the

laser

beam

in

the

process

of

exposing,

and

an

electrostatic

latent

image

is

formed

on

the

OPC

belt

as

the

result.

iv)

Negatively

charged

toner

is

moved

onto

the exposed

part

of

the

OPC

belt

in

the

development

process

due

to

the

difference

of

potential

between

-VR(V)

and

-

DBV(V),

and

a

visible

toner

image

is

formed

as

the

result.

v)

Negatively

charged

toner

on

the

OPC

belt

moves

to

the

transfer

drum

surface

in

the

transfer

process

because

the

GND

potential

of

the

transfer

drum

is

greater

than

-VR(V)

of

the

OPC

belt.

vi)

The

OPC

belt

is

discharged

by

the

erase

lamp.

Process

•

M

OV

4

l=>

Transfer

Drum

GND

OPC

Belt

Belt

T

CBV

-CBV

\

11

-

VR

DBV

''

-

Vo

%\%%

I

II

Charger

T

la

i

lv

I

Toner

_

.............

ii

,

......

oner

..

.....

.....

—..

Dev.

roller

El

Charging

Process

al

Exposing

Process

al

Developing

Process

El

Transfering

Process

T

[33

Cleaning

(Erase)

DBV

CBV

Power

Supply

for

OPC

Belt

Bias

Power

Supply

for

Charging

1:€13

DBV

Power

Supply

for

Dev.

Roller

Bias

nl

Remain

voltage

on

the

OPC

Belt

Fig.

4-10

4-11

Brother International HL-3400CN Service Manual - Page 62

€13

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