Oce 7050 Technical & Service Manual page 116

Functional description
1 Toner transfer
The positively charged toner is attracted to the negatively charged latent image
on the drum. Now the toner has to be transferred to the paper. A transfer corona
charges the paper negatively. When we make sure that the force between paper
and toner is stronger than the force between drum and toner, the toner particles
will move to the paper.
toner particles
paper
Not all toner is transferd to the paper; because of the negative charge on the
drum, some toner remains on the drum. This toner will be removed with a
cleaning blade.
2 Separation
The transfer corona charges the paper negatively, while the drum substrate is
charged positively. Therefore the paper will stick to the drum. An AC voltage
of 500 Hz connected to a separation corona separates the paper from the drum.
When the separation is not successful, a pick-off pawl keeps the paper away
from the drum. This causes an ORE.
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transfer corona
drum
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pick-off pawl
06 Transfer 501