Canon CLBR 460ps Service Manual page 107

d. Waste toner full detection
The waste toner full is detected by the waste toner full sensor (PS13).
PS13 consists of a light emitter and a light receiver. The light from the emitter passes through
the light guide and enters the detection port of the drum cartridge. The light entered the port
passes through the cartridge when the waste toner around the detection port is scraped off by
the stirrer. The light passes through the waste toner container and is detected by the light
receiver. The DC controller detects the time until the waste toner covers the port and blocks the
light again.
If the time the light passes becomes lower than a prescribed value, the DC controller deter-
mines that the waste toner level is high and reports the waste toner full warning to the video
controller. The DC controller writes this data into the drum cartridge memory.
This printer is capable of printing after the waste toner full warning has been reported. After
issuing the warning, the DC controller starts counting the number of prints and stores it in the
drum cartridge memory. When the specified number of prints is reached, the DC controller
determines that the limit of the waste toner has been reached, stops the printer, and notifies the
video controller of the waste toner full.
Photosensitive
drum
Note: If the waste toner full is detected when the accumulated photosensitive drum con-
sumption time is equal to or less than 10% consumption ratio, the DC controller noti-
fies the video controller of an abnormal waste toner sensor instead of a waste toner full
warning.
Waste toner full sensor
Light receiver
Toner feed plate
Waste toner container
Waste toner
Figure 2-4-5
(PS13)
Light emitter
CHAPTER 2
Light guide
Stirrer
Detection port
2 - 49