Toner Transfer To The Accumulator Belt; Figure 5-8 Toner Transfer To The Accumulator Belt - Tektronix Phaser 550 Service Manual

Toner transfer to the accumulator belt

As the photoconductive belt rotates, it comes in contact with the accumulator
belt, which rotates at the same speed. The first bias transfer roller, located under
the accumulator belt at the contact point with the photoconductive belt, carries a
charge which varies between +300 and 350 volts based on the humidity, media,
and print speed. This strong potential attracts and holds the toner from the
photoconductive belt to the accumulator belt. The accumulator belt rotates four
times so it can pick up or accumulate each of the four toner layers, one layer on
top of the last. An accumulator belt home-position sensor sync signal, generated
from a timing mark on the accumulator belt, informs the engine control board
that it is time to begin exposing the next toner layer's information onto the
photoconductive belt. When that happens, the accumulator belt is rotated in the
proper position to transfer the toner layer in proper registration with the
previous layer(s).
Any toner remaining on the photoconductive belt after the transfer to the
accumulator belt is scraped off by the photoconductive belt cleaning blade,
which is always in contact with the belt. This leaves the photoconductive belt
clean for the next layer of toner to be transferred from the toner cartridges.
Photoconductive belt
cleaning blade
The pre-transfer
charger gives the
toner a uniform
negative charge
Accumulator
belt home
First bias
sensor
transfer
roller

Figure 5-8 Toner transfer to the accumulator belt

+300 ~ 350v
Accumulator
belt
Theory of Operation
Photoconductive
belt
The toner on the
photo-conductive
belt is attracted to
the strong positive
potential of the first
bias transfer roller.
Four layers of toner,
latent images of
cyan, magenta,
yellow and black,
build up on the
accumulator belt
9322-88
Service Manual 5-11
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