Ricoh Aficio FX10, Service Manual

Page: 38 / 284

2.2. PRINTING
2.2.1. Printing Process - Overview
This machine uses a “write to black” system, using negative toner.
•
The charge corona wire gives the drum surface a negative charge of
-750 V.
•
The exposed area on the drum drops to about -100 V.
•
The development roller carries toner to the latent image on the drum sur-
face.
Development bias (during printing):
Toner application roller : -700 V
Development roller: -400 V
Switching bias:
Toner application roller : -50 V
Development roller: +250 V
•
The transfer roller pulls the toner from the drum onto the paper.
A constant current of +4
µ
A is applied. The antistatic brush helps to
separate the paper from the drum.
•
The cleaning blade removes any toner remaining on the drum after the
image is transferred to the paper.
•
The quenching lamp reduces the negative charge on the drum to about
-50 V.
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June 10th, 1997 DETAILED SECTION DESCRIPTIONS
PRINTING
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