Panasonic UF-4500, Service Manual

Page: 241 / 365

241
UF-5500 / 4500
13.2.4. Developing and Transcription
The developing is the stage that the OPC drum with an invisible image is changed to visible by the toner. The drum cartridge con-
sists of mixing paddle, toner supply roller, developing roller, developing blade, charge wire, grid plate and OPC drum. The bias volt-
age is added to the developing roller and toner supply roller. Firstly the toner is mixed up in the mixing paddle and plus-charged by
triboelectricity, then led to the toner supply roller. Secondly the potential difference causes to send the toner to the developing roller
from the toner supply roller. The supplied toner to the developing roller is kept to a certain layer thickness by the developing blade
and also it is charged by triboelectricity. Consequently the toner is transferred to the surface of the exposed OPC drum by the
potential difference between the developing roller and OPC drum's surface.
The transfer is the stage that the created image on the OPC drum is transferred to the paper. When the transfer roller is minus-
charged with the image, the plus-charged toner particles are gathered on the surface of the drum and transferred to the paper.
Developing and Transcription Part
Transfer Roller
Developing Roller
OPC Drum
Paper Path
Toner Supply Roller
Mixing Paddle
Triboelectric Charging
Developing Blade
Transcription Bias -4~-25
µ
A constant current(-500~-4200V)
(depends on the printing ratio)
Developing Bias
and supply Bias
DC170~240V
+AC330VP-P
(depends on the
ambience and the
lifetime)
+
+
Grid Bias
+475V
+
+
+ +
+
+
+
+
+
+
+
+
+
+
Charging Bias
+200
µ
A
Constant current
(4.1~4.6kV)