Toner Control - Minolta Magicolor 3100 Series Service Manual

7.7 Toner Control

Whether the toner bottle is installed is detected by the SWITCH TCRU ASSY, and the presence of toner in
the toner bottle is detected by the SENSOR TONER LOW. These switches and sensors are provided for
respective colors, and detection is made for each color.
7.7.1 SENSOR TONER LOW
The SENSOR TONER LOW is provided for each color, but the printer cannot detect all colors at a time, but
detects one color each. It detects one color per 3.5 seconds, thus requiring 14 seconds for detecting four
colors. Accordingly, the presence of toner is detected once per 14 seconds for each color.
The SENSOR TONER LOW is attached to the HOLDER TCRU ASSY, and it detects the presence of toner
dispensed by the Toner Motor from the toner bottle into the HOLDER TCRU ASSY.
Also, the SENSOR TONER LOW could make a wrong detection if the toner sticks to the sensor surface. To
prevent this, the film attached in the vicinity of the Auger in the HOLDER TCRU ASSY cleans the sensor
surface when the toner is dispensed. This film rotates together with the Auger at the toner dispensation to
scrape the toner off the SENSOR TONER LOW surface. However, the sensor may detect the toner even if
the toner is not present or may not detect the toner even if the toner is present, depending on the film
position when the Toner Motor stopped. This is avoided by the printer internal control.
7.7.2 Toner presence control
The control is outlined below.
1) Check timing
• When the power is turned on, or the front cover is opened and closed
• Every 14 seconds
2) Output of "Toner Empty Warning"
The "Toner Empty Warning" is outputted, if the SENSOR TONER LOW detects toner empty two ore
more times continuously and also the toner is dispensed during the time of 2-time detection.
This is taken place to prevent a wrong detection depending on the film position as described in "7.7.1
SENSOR TONER LOW".
3) Output of "Toner Empty Error"
After the output of "Toner Empty Warning", the toner dispense time is counted up, and if it exceeds the
specified value, the "Toner Empty Error" is outputted.
4) Reset of "Toner Empty Warning"/"Toner Empty Error"
After the output of "Toner Empty Error", the toner is dispensed for 1.5 seconds when the toner bottle
installation is detected. At the subsequent toner presence control timing, if the SENSOR TONER LOW
detects the toner presence, the "Toner Empty Warning" and "Toner Empty Error" are reset.
However, in such a case, the controller regards this status as "toner empty". When the toner is
dispensed and the SENSOR TONER LOW detects the toner presence three or more times
continuously, the controller regards this status as "toner presence".
Chapter 6 Principles of Operation
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