Xerox PHASER 7500 Service Manual

Phaser 7500 Printer Service Manual 2-17
Theory of Operation
Electric Discharge
The charge on the paper is neutralized/removed by the Detack Saw (serrated
metal plate) to peel off the paper from the belt.
• The Detack Saw is a serrated metal plate with an acute edge that is connected
to the frame ground.
• The Detack Saw is close to the back of the paper. If the charge that was
applied to the paper in the "Secondary Transfer" process gets discharged
unevenly to the chutes and other metallic parts before the fusing, it will cause
image distortion and toner dispersion. To prevent this, the positive charge that
was applied to the paper is actively discharged by the Detack Saw so as to
evenly neutralize/remove it.
Cleaning (Belt/ 2nd BTR)
The non-transferred toner on the belt and the unwanted toner that is stuck to the
2nd BTR are removed after the toner image has been transferred to the paper.
• Cleaning the Belt - Toner that was not transferred to the paper during the
"Secondary Transfer" process remains on the belt surface. Because this toner
will interfere with the subsequent processes if allowed to remain on the belt
surface, the Cleaning Blade that is in contact with the belt scrapes off the
remaining toner, which is then transported by the Belt Waste Toner Collector
into the Waste Cartridge.
• Cleaning the 2nd BTR - Unwanted toner that adhered to the 2nd BTR during
the "Secondary Transfer" process will dirty the back side of subsequent paper.
To prevent this, positive DC Voltage from the HVPS is applied to the Backup
Roll that faces the 2nd BTR to transfer the toner on the 2nd BTR back to the
belt. The Cleaning Blade that is in contact with the belt then scrapes off the
toner that was transferred back to the belt, which is then transported by the
Belt Waste Toner Collector into the Waste Cartridge.
s7500-352
2nd BTR
Belt
: Negative Charge
: Positive Charge
: Toner
Cleaning Roll
Backup Roller
1st BTR (K)
1st BTR (C)
1st BTR (M)
1st BTR (Y)
Drum (K)
Drum (C)
Drum (M)
Drum (Y)
HVPS

Xerox PHASER 7500 Specifications

General

Brand	Xerox
Model	PHASER 7500
Category	Printer
Language	English