Toner Supply Mechanism - Ricoh B202 Service Manual

DEVELOPMENT

6.8.5 TONER SUPPLY MECHANISM

[B]
[A]
B178D549.WMF
Overview
The air transport system agitates the toner [H] in the toner cartridges [G]. Toner is
transported to the development unit [A] by the toner attraction pump [B] (each
cartridge has a separate pump). This provides a more stable way to transport fine
powder than previous methods.
Toner Agitation and Attraction
The rear air pump [D] supplies air to the yellow and magenta toner cartridges. The
front air pump [E] supplies air to the black and cyan toner cartridges. Air agitates all
the toner in each cartridge. The pumps and four valves [C] control the airflow.
Mixed with air, the toner passes part of the way along the transport tube [I] towards
the toner attraction pump. This pump draws the toner the rest of the way (
Transport).
The air pump turns on to supply air to the toner cartridges for one second under the
following conditions:
• During normal operation (when the "on" time for a toner supply clutch
reaches a certain value).
• When forced toner supply (SP2-207) is done
• When forced toner density adjustment (SP3-126-002) is done
• At toner end recovery
• Developer initialization
The filter [F] on the inner package of the toner cartridge ensures that the internal
pressure does not become too high.
B202/B178/B180
[C]
[D]
6-62
[E]
[F]
[G]
[H]
[I]
Toner
SM