Kyocera Mita DC-2060, Service Manual

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1AH
1-3-26
Developing bias
CN1-7
MPCB
DB REM
TNS CNTL
TNS SENS
TFM1
TFM
TNS
CN5-17
CN5-15
CN5-12
CN5-13
DB
1-8 2-7
HVTPCB
TEDSW
TEDSW
CN5-9
CN23-1
CN23-3
TFM2
ET-TH
T/HSENS
HUM-SENS
Figure 1-3-23
Toner density control
The toner density is detected by the toner sensor (TNS) installed on the developing unit.
When a certain quantity of the developer passes the sensor detection section, the carrier
proportion by weight is converted into a voltage and output to the main PCB (MPCB). The
main PCB CPU can detect the toner density from this voltage (toner sensor output voltage).
As the toner is consumed and the proportion of the carrier by weight in the developer
increases, the toner sensor output voltage rises.
Toner density is controlled by switching the toner feed motor on/off using as the reference
the toner sensor initial output value set when simulation 60 was executed when the
developer was set. On this device, a magnetic proximity switch toner level detection switch
(TEDSW) is also used, but the toner remaining amount is not detected until the toner empty
state is detected from the toner sensor output voltage.