Toshiba e-studio281c - Color Auto-Toner Sensor Circuit

12
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DEVELOPER UNIT
12 - 11
12.5.3 Color auto-toner sensor circuit
1) General descriptions
The color auto-toner sensor detects the toner amount on the color developer sleeve with the reflec-
tion- type photosensor, differing from the black auto-toner sensor. Light-receiving elements of diffuse
reflection in this sensor detect the toner amount on the sleeves with the light amount reflected from
the sleeve surface. It detects the toner amount at the first forward position from the developing posi-
tion.
When the toner runs out, it supplies the toner from the toner cartridge with the color toner supply
auger driven by the color developer toner supply clutch.
Also, the color auto-toner sensor has a shutter which opens and closes by the solenoid. It prevents
stain to the sensor and calibrates the sensor with the reflection from the shutter.
Fig. 12-9
D/A
converter
Engine
CPU
A/D converter
Gate array
#2
Gate array
#1
ASIC
North Bridge
System
CPU
FRAM
NVRAM
Control panel
SYS board
Control unit
LGC board
LCD panel
Control voltage signal
Shutter driving signal
Toner density signal
Color auto-toner sensor
Color auto-toner sensor
shutter solenoid
Color
developer
toner supply
clutch
Developer
motor
Clutch control signal
Color toner
cartridge
Color developer
unit
Color toner
cartridge sensor