Magnet Roller - Minolta EP5000 General, Mechanical/Electrical

Interleaf EP5000/EP4000 GENERAL, MECHANICAL/ELECTRICAL
97.04.01
1156SBM1302A

13-2. Magnet Roller

The Magnet Roller of the Sleeve/Magnet Roller of this copier has the following magnetic
characteristics. Pole S3 before poles N1 and N2 at which development takes place
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 S3 goes to those uncovered areas because of
the weak magnetic force. This helps prevent white lines from occuring on the copy.
The magnetic flux density is maximized to allow the bristle to stand high and upright at
poles N1 and N2, at which development takes place. The positioning of these two like
poles together helps agitate the developer for greater uniformity, thus preventing white
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
development. This means that developer fresh from the Developer Mixing Chamber is
always brought to the point of development.
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 Magnet Roller has therefore been made movable: the Bushing is pressed by
compression springs thereby pressing the Positioning Collars on both ends of the
Magnet Roller against the PC Drum. This ensures a given distance between the PC
Drum and the Sleeve/Magnet Roller.
S2
S3
N1
N2
N3
S1
Movable Bushing
Fixed Bushing
PC Drum
M-39
N4
Compression Spring
1156M016AA