Toshiba E-STUDIO900 - Manual (Page 74)

PTM 2-49 B070/B071
2.6.2 DEVELOPMENT MECHANISM
Toner and developer are mixed in the toner agitator by the cross-mixing roller [A]. The
paddle roller [B] picks up the developer and sends it to the upper development roller
[C]. Internal permanent magnets in the development rollers attract the developer to the
development roller sleeve. Developer from the upper development roller sleeve is also
attracted to the lower development roller [D].
The upper development roller carries the developer past the doctor blade [E] which
trims the developer to the desired thickness. Backspill (excess toner) spills over the
separator [F] to the toner transport coil [G] which sends the developer from back to
front to the cross-mixing roller.
In this machine, black areas of the latent image are at a low negative charge (about –
150 V) and white areas are at a high negative charge (about –800 V).
The development roller is given a negative bias to attract negatively charged toner to
the black areas of the latent image on the drum.
The development rollers continue to turn, carrying the developer to the drum [H].
When the developer brush contacts the drum surface, the low-negatively charged
areas of the drum surface attract and hold the negatively charged toner. In this way,
the latent image is developed.
B070D303.WMF
[A]
[B]
[C]
[D]
[G]
[H]
[E] [F]