Ricoh SAVIN D0AP Service Manual page 608

7.6.4 TONER CARTRIDGE
Overview
The toner cartridge contains the toner hopper, toner supply mechanisms, and the used
•
toner collection box.
• The toner supply port on the toner cartridge has a shutter that opens when the toner
cartridge is installed.
• This machine conducts toner recovery control only during high-volume print jobs with a
high rate of page coverage or when toner supply errors occur.
Toner Cartridge Mechanism
Toner Supply
The toner supply clutch (CL2) turns ON and the coils in the toner cartridge rotate to transfer
toner to the box tap and then the PCDU. The toner transferred to the PCDU is transferred to the
development unit by the 1st mixing coil.
Toner Recovery Control
When the machine detects the lower limit for the amount of toner in the developer, printing
stops and then the machine supplies toner as the amount is being checked as the machine
idles.
This sequence, (toner supply > toner amount detection > idling) comprises the toner recovery
sequence. This sequence is performed to avoid insufficient toner supply and other problems.
The previous machine always performed toner recovery when the amount of toner in the
developer reached its lower limit, meaning toner recovery usually took place just before toner
near-end when it was easy to detect the lower limit, resulting in lower productivity each time this
was done.
In regard to this issue, this machine maintains the correct amount of toner (near the upper limit)
in the developer by replenishing toner while the machine is printing. Furthermore, toner recover
control is performed only during high-volume print jobs with a high rate of coverage (25% or
more on the sheets), or when a problem occurs in toner supply. In this way, the problem of
reduced productivity in the toner recovery sequence at toner near-end with the previous
machine has been solved.
New Unit Detection
The machine reads the ID chip to detect the status of the cartridge.
ID Chip Information
The toner cartridge for this machine is equipped with an ID chip [A] that records the cartridge
serial number and the date the cartridge was installed.
D0AP/D0C4/D0C5/D0C6/M0BQ/M0D1 7-46
PCDU, Toner Cartridge
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