Toshiba e-studio550 Service Manual page 164

11. 2. Functions
(1) Drum cleaning blade
It is pushed to the drum with a certain pressure by a weight and scrapes off the residual toner on the
drum surface. The pressure is released and the blade is separated from the drum by turning the cam
manually.
(2) Drum recovery blade
It catches the toner scraped by the drum cleaning blade.
(3) Recovered toner transport auger
It transports the scraped toner to the recycle unit.
(4) Drum separation finger
It is pushed to the drum by a solenoid only when the leading edge of the paper passes in order to
separate the paper which has not been separated by the transfer belt.
(5) Image quality sensor
It assesses the relative reflective rate for the test pattern (toner image) formed on the drum in order to
keep the image density and line width properly.
(6) Drum thermistor
Since the charging amount changes depending on the temperature of the drum surface, the drum
thermistor detects the temperature of the drum surface and controls to unify the charging amount.
(7) Drum cleaning brush
It eliminates the paper dusts and extraneous substance adhered to the drum surface after separating
the paper and also decrease the friction of the drum cleaning blade to lengthen its life span, which
improves the image reliability.
11. 3. Drum Temperature Detection Circuit
Thermistor
At this detection circuit, the voltage gained by the R33 and thermistor is input into the A/D converter of
IC 58 to detect the drum surface temperature.
e-STUDIO550/650/810 DRUM/CLEANER UNIT
+5V
R33
R32
C186
Drum temperature detection circuit
11 - 2
Main
CPU
IC58
JUNE 2002 © TOSHIBA TEC