Xerox PHASER 7500, Service Manual

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2-4 Phaser 7500 Printer Service Manual
Theory of Operation
Phaser 7500 Operational Overview
The Phaser 7500 is a LED Print Head Color printer that is based on the
electrophotographic recording principle. It utilizes a tandem system where each of
the colors - Yellow, Magenta, Cyan, and Black (Abbr: Y, M, C, K) has its own Drum
and Developer. A toner image for each color is formed on the Drum and then
transferred to the belt (Intermediate Transfer Unit). The toner image of the 4
colors are overlapped on the belt to form the full color print, which is then
transferred and fused onto the paper.
System Overview
The Phaser 7500 consists of the Control Panel, Print Engine, Duplex Unit, and
Optional Sheet Feeder.
The print process of the printer consists of the following steps:
1. Electric Charge - Charges the Drum surface.
2. Exposure - Exposes the Drum surface with LED (Light Emitting Diode) to form
the image.
3. Development - Develops the image section on the Drum surface with toner.
4. Primary Transfer - Transfers the toner image on each Drum to the belt.
5. Cleaning - Discharges each Drum and removes any remaining Toner on the
Drums and Bias Charge Roller (BCR).
6. Secondary Transfer - Transfers the toner image on the belt to paper.
7. Electric Discharge - Discharges electric charge on the paper.
8. Cleaning - Removes any remaining Toner on the belt and 2nd Bias Transfer
Roller (BTR).
9. Fusing - Fuses the toner on the paper with heat and pressure.
Drum (Y)
Drum (M)
Drum (C)
Drum (K)
1.
Electric
Charge
2.
Exposure
3.
Development
5.
Cleaning
4.
Primary
Transfer
1.
Electric
Charge
2.
Exposure
3.
Development
5.
Cleaning
4.
Primary
Transfer
1.
Electric
Charge
2.
Exposure
3.
Development
5.
Cleaning
4.
Primary
Transfer
6.
Secondary
Transfer
7.
Electric
Discharge
9.
Fusing
8.
Cleaning
1.
Electric
Charge
2.
Exposure
3.
Development
5.
Cleaning
4.
Primary
Transfer
Belt
Paper
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