Transfer Block - Canon LBP2900 series Service Manual

step 3:Å@development
This is where toner is put over the static image formed on the surface of the photosensitive drum.
As shown in the figure, the developing assembly is made up of a developing cylinder (which in turn consists of a fixed magnet and a cylinder that rotates
around it) and a rubber blade. It also holds toner inside it.
The toner is composed of magnetite and resins, and is held to the cylinder by means of magnetic force. The toner possesses insulating properties and is
charged to a negative potential as the result of friction against a rotating cylinder.
The potential of the area of the photosensitive drum that has been exposed by a laser beam is higher than that of the negatively charged toner on the cylinder;
thus, when the area comes close to the layer of the toner (possessing a negative potential) on the cylinder, the difference in potential between the drum
surface and the cylinder will cause the toner to move to the drum surface, turning the static image on the drum surface into a visible image.

2.4.1.5 Transfer Block

This block consists of 2 steps which are used to move the toner image on the surface of the photosensitive drum to print paper.
Step 4:Å@Transfer
In this step, a positive charge is applied to the back of print paper to attract toner from the surface of the photosensitive drum.
step 5:Å@separation
In this step, the machine takes advantage of the rigidity of print paper to detach it from the photosensitive drum. The static eliminator serves to decrease
the charge on the back of print paper, thus weakening the static bond of paper and facilitating the separation.
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Photosensitive
drum
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Chapter 2
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