Toner Sensor - Brother HL-1440 Service Manual

CHAPTER 3 THEORY OF OPERATION
2.3 Sensors
2.3.1 Cover sensors A and B
Detect opening and closing of the front cover.
Cover sensor (B)
Cover sensor (A)
2.3.2

Toner sensor

Detects if there is toner in the toner cartridge. The toner sensor at the left side emits light
through the window on the left side of the toner cartridge, then the toner sensor at the right
side receives it when the toner is low. They also detect whether or not the drum unit is
installed. (The toner cartridge is installed in the drum unit.)
Toner sensor
(light emission)
Fig. 3-32
Fig. 3-33
3-26
Toner sensor
(light reception)