Toner Density Control - Ricoh A028 Service Training Manual

Toner Density Control

2.10 Toner Density Control
2.10.1 Outline of toner density control
Main switch ON
(or at 500 copies end)
Always
Fundamentally, this machine uses the toner density sensor to control the amount of toner supplied
to the development unit, and thus maintain a stable toner density in the development unit.
However, even with this operation, the image density on copies may vary due to changes of
environmental conditions, such as temperature and humidity. To make image density steady, the
toner density control is modified by the ID sensor.
2.10.2 ID sensor operation
ID sensor pattern production timing
When the main switch is ON (only when more than one
hour has passed after the main switch is OFF), or after
500 copies or more are completed, the machine enters
the ID sensor mode, and an ID sensor pattern is
produced.
Main
switch ON
2-74
1 July 1994
ID sensor
OPC idling pattern erase
mode
ID sensor
mode