EXP Computer C4077-90960 - Manual (Page 98)

Toner Cartridge
The toner cartridge is the “heart” of the Image Formation System. It houses
the cleaning, conditioning, and developing steps of the process. The toner
cartridge contains the photosensitive drum, primary charging roller,
developing station, toner cavity, and cleaning station. Including the
components that wear, degrade, or are consumed in a customer replaceable
toner cartridge eliminates the need for a service call when replacement is
required.
Toner Cartridge/High Voltage Power Supply Contacts
The toner cartridge has three contacts which route voltage from the HVPS
PCA. They are:
•
Upper: Primary Charge
•
Middle: Developing Bias
•
Lower: Toner Sensing/Toner Recognition
The Photosensitive Drum
The image from the Laser/Scanner Assembly is written on the drum
surface, developed, and transferred to the media. The drum is an aluminum
cylinder. The aluminum base of the photosensitive drum is electrically
connected to ground potential. The outside of the cylinder is coated with a
layer of non-toxic organic-photoconductive material (OPC). The OPC
material becomes electrically conductive when exposed to light. The drum
surface is first cleaned of excess toner, then conditioned with a uniform
negative charge. When an area on the drum surface is exposed to the laser
light beam, the negative charge in that area is conducted to the ground
potential of the drum base and thus becomes more positive. Areas not
exposed to light remain non-conductive and maintain their negative charge.
Photosensitive Drum
Figure 5-7
5
Functional Overview
Functional Overview 5-13