Kyocera Mita DC-2060, Service Manual

Page: 48 / 437

1AH
1-3-24
Formation of magnetic brush
The developing roller consists of a magnet roller with five poles and a sleeve roller. Rotation
of the sleeve roller around the magnet roller entrains developer, which in turn forms a
magnetic brush at pole N1 on the magnet roller. The height of the magnet brush is regulated
by the doctor blade; the developing result is affected by the position of the poles on the
magnet roller and the position of the doctor blade.
A developing bias voltage generated by the high-voltage transformer (HVTPCB) is applied
to the developing roller to provide image contrast.
1 3
6 5 4
2
A
N1
N2
S3
S1
S2
N1: 850
×
10
–4
±
50
×
10
–4
T
N2: 600
×
10
–4
±
50
×
10
–4
T
S1: 600
×
10
–4
±
50
×
10
–4
T
S2: 600
×
10
–4
±
50
×
10
–4
T
S3: 500
×
10
–4
±
50
×
10
–4
T
A: Distances between the doctor blade and
developing roller = 0.6
±
0.05 mm
Magnetic poles on the developing roller
70
°
70
°
60
°
70
°
Figure 1-3-21 Forming a magnetic brush
1
Developing unit housing
4
Doctor blade
2
Developing roller
5
Right developing spiral
3
Toner sensor (TNS)
6
Left developing spiral