Dell 3010CN Service Manual page 574

TC control procedure is shown below.
(1) Adjustment of Sensor ADC
Composition of Sensor ADC is as shown in the Fig. There are 2 LEDs for black and color, and
each patch concentration is read according to 2 reflecting routes with different optical angles.
LED for black is for specular reflection light path and LED for color is for diffuse reflection
light path.
Parts for switching light path
of reference plate
Belt
(2) Adjustment due to environmental facts and part deterioration
Every change in temperature/humidity and deterioration of parts such as IBT Belt or Drum
due to printing job affects image quality. Temperature/humidity data sent from Sensor
Environment and usage information of device sent from Crum are checked, and this
information is incorporated and used for correction at correcting parameters.
(3) Creation of toner patch
Output value of HVPS, laser intensity value and toner supply quantity are determined
according to parameter calculated using various information, and 4 patches of each color are
created on the belt surface.
(4) Reading of toner patch
Sensor ADC reads the concentration of created toner patch, and if read value is different from
ideal value when they are compared, parameter is calculated again and step (3) is returned to.
If read value is extremely thin or thick, carry out the following control procedures.
Admix control
If patch concentration read by Sensor ADC is extremely thin, carry out toner increase in
order to supply toner to Developer Assy. This procedure is called "Admix control".
Sweep control
If patch concentration read by Sensor ADC is extremely thick, transfer toner to drum and
scrape toner from inside Drum Cleaner in order to discharge toner forcibly from
Developer Assy. This procedure is called "Sweep control".
Built in reference plate
Position when shutter is closed
(reference plate is detected)
6 - 37
Chapter 6 Principle s of O peration
LED for diffuse reflection
(For YMC)
Position when shutter opens,
Position at (Patch detection)
Common light
receiving element
LED for front reflection (For K)
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