Electrophotographic Process; Electrophotographic Printing Process Timing Chart (Figure 2-8) - OKIDATA OL600e Service Manual

2.4.2

Electrophotographic Process

The electrophotographic processing is outlined below. Figure 2-7 shows the electrophotographic
printing process.
1 Charging
The surface of the image drum is given a uniform negative charge by applying the negative
voltage to the charge roller.
2 Exposure
Light emitted from the LED head irradiates the negatively charged surface of the image drum.
The surface potential of the irradiated portion becomes lower, forming the electrostatic latent
image associated with the print image.
3 Developing and toner recovery
When the negatively charged toner is brought into contact with the image drum, it is attracted to
the electrostatic latent image by static electricity, making the image visible.
At the same time, the residual toner on the image drum is attracted to the developing roller by
static electricity.
4 Transfer
When paper is placed over the image drum surface, the positive charge which is opposite in
polarity to that of the toner, is applied to the reverse side by the transfer roller. The toner is
attracted by the positive charge and is transferred onto the paper. This transfers the toner image
formed on the image drum onto the paper.
5 Temporary cleaning
Residual toner, which remains on the image drum without being transferred, is evened out by the
cleaning roller and is attracted to the cleaning roller by static electricity.
6 Fusing
The transferred toner image is fused to the paper by heat and pressure.

Electrophotographic Printing Process Timing Chart (Figure 2-8)

PRINT-N
PRDY-N
DM-ON-N
RM-ON
INSNS
OUTSNS-N
Operation Description
Feed start IN Sensor OFF
2 - 14
OUT Sensor OFF Feed stop
OL600e/610e/610e-PS/610e-S
Service Manual, P/N 59271602