Toner Low Detection - Oki OKIFAX4550 Maintenance Manual

4.

Toner Low Detection

• Hardware configuration of toner sensor
The figure below shows the hardware configuration of the toner sensor.
• Toner detection method
Toner sensor
(1) Toner sensor monitoring conditions are shown in the figure below.
Caution: The toner sensor is not monitored when the drum is inactive.
(a) When the toner-low state continues twice, Toner Low occurs. (This state is monitored
at a cycle of 40 milliseconds.)
(b) When the toner-full state continues twice, Toner Low is released. (This state is
monitored at a cycle of 40 milliseconds.)
When the toner sensor does not change over two cycles (T × 2), the toner sensor alarm
(c)
state occurs.
(d) After the EP unit has been replaced (after the drum counter has been reset), Toner Low
is not detected when the drum counter indicates 1 to 100 counts.
(2) The basic rotation cycle of the toner sensor is as follows:
41309401TH Rev.4
Photointerrupter
Hardware Configuration of Toner Sensor
Magnet draw-in
t1
Basic rotation cycle of toner sensor
Toner low time
Toner full time
Image drum unit
Agitation bar (iron)
Magnet
Toner sensor lever
T
T time
4.9 sec.
t1 > 1.2 sec.
1.2 sec. > t1 >
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