I I-2. Magnet Roller - Minolta EPI 054 User Manual

FrameMaker Ver.5.5(PC) EP1054/EP1085/EP2030 GENERAL, MECHANICAL/ELECTRICAL
98.04.24
1174SBM1102A
11-2. Magnet Roller
The Magnet Roller of the Sleeve/Magnet Roller of this copier has the following magnetic
characteristics. Part of pole S2 before the principal N1 pole (i.e., the area marked as S2b in
the Fig. below) provides a very weak magnetic force. If developer is compacted and clogs
at the Doctor Blade and, as a result, part of the surface of the Sleeve/Magnet Roller is not
covered with developer, the nearby developer around S2b goes to those uncovered areas
because of its weak magnetic force. This helps prevent blank lines from occurring on the
copy.
The Sleeve Roller, onto which developer is attracted by the magnetic fields of force set up
by the poles of the Magnet Roller, turns to convey the developer toward the point of devel-
opment.This also means that developer fresh from the Developer Mixing Chamber is
always brought to the point of development.
As noted earlier, the Imaging Unit integrates the Developing Unit with the PC Drum into one
body. Because of that, it is impossible to move the Developing Unit against the PC Drum,
thereby providing a certain distance between the PC Drum and Sleeve/Magnet Roller. The
Sleeve/Magnet Roller has therefore been made movable: the Bushing is pressed by com-
pression springs thereby pressing the Positioning Collars on both ends of the Sleeve/Mag-
net Roller against the PC Drum. This ensures a given distance between the PC Drum and
the Sleeve/Magnet Roller.
Magnetic Pole Positioning
Pole Having Weak
Magnetic Force
Movable Bushing
Compression Spring
1139M016AA
Fixed Bushing
1139M017AA
PC Drum
M-36