Oki C5500 Maintenance Manual page 34

Principle of toner sensor detection
Toner LOW is detected by the toner sensor (Reflection sensor) installed inside the printer. The
shielding plate is mounted inside the ID and rotates in synchronization with toner agitation.
Moreover, the ID has a shutter fitted. The shutter is synchronized with the operation lever of the
toner cartridge, and the toner sensor can detect that the toner cartridge has been loaded properly.
Detection may not take place normally, and a toner sensor error may be issued, if the shield plate
or toner sensor is stained with toner, or if the ID unit and toner sensor do not remain exactly opposite
to each other in their positions.
Principle of toner counter
After image data is developed to binary data which the printer can print, it is counted by an LSI as
a number of print dots. The amount of toner consumed is calculated from that count value, and the
remaining amount of toner is thus indicated. As opposed to this, the toner LOW detection by the
toner sensor is implemented when the toner amount remaining inside the ID unit physically
decreases to below a certain level.
Principles of ID, belt and Fuser counters
ID counter:
Belt counter:
Fuser counter:
43085101TH Rev.1
Shutter
Shield
Toner Sensor
One count represents the value that results from dividing the amount of rotation
of the drum by three when three A4-size sheets are printed continuously.
One count represents the value that results from dividing the amount of rotation
of the belt by three when three A4-size sheets are printed continuously.
One count is registered when paper is shorter than the length of Legal 13-inch
paper. When paper is longer than that, the count number is determined by the
number of times the Legal 13-inch paper length is exceeded. (Decimal fractions
rounded up)
plate
Oki Data CONFIDENTIAL
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