Process Control - Ricoh G-P3 Service Manual

6. Detailed Function Descriptions

Process Control

Overview
6
This machine has the following two forms of process control:
• Potential control
• Toner supply control
Process control uses the following components:
• Three ID (image density) sensors (left [A], center [B], and right [C]). Only the center ID sensor is used
for process control. The left, center, and right ID sensors are used for line positioning and other
adjustments.
• TD (toner density) sensor in each development unit.
Potential Control
Overview
Potential control controls development to keep the toner images on the drums at the same density. It does
this by compensating for variations in drum chargeability and toner density.
The machine uses the ID sensor to measure the reflectivity of the transfer belt and the density of a standard
sensor pattern. This is done during the process control self-check.
The machine measures these values from the ID sensor output and a reference table in memory.
• V : Drum potential without exposure – to adjust this, the machine adjusts the charge roller voltage.
D
• V : Development bias
B
• V : Drum potential at the strongest exposure – to adjust this, the machine adjusts the laser power.
L
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