Toner End Detection; Mechanism; Toner Near-End Detection - Ricoh Gestetner LANIER SAVIN G071 Service Manual

6.6.4 TONER END DETECTION

Mechanism

[A]: Optic fiber
[B]: Light emission
[C]: Gap
An optic fiber [A] in each development unit
detects toner end. Light is emitted from
the rear end [B] of the unit. There is a gap
[C] in the optic fiber.
When the development unit is filled with
toner, the toner breaks the light path
through the gap. When the unit is running
out of toner, the light path is not broken.

Toner Near-End Detection

The machine uses two methods simultaneously: pixel count, and toner end sensor.
If either of these methods detects near-end, the machine indicates near-end.
Near-End by Pixel Count
The machine counts how many pixels have been printed with each toner cartridge.
When there are 1000 (starter toner) or 2000 (normal toner) prints remaining until
the estimated toner end condition, toner near-end is indicated.
Near-End by Toner End Sensor
• If the toner end sensor output drops to toner end level, counter 1 is set to 1.
• If the above condition (counter 1 is 1) is detected twice accumulated 14 seconds
while the development clutch is activated, counter 2 is set to 1.
• If the above condition (counter 2 is 1) is detected twice continuously, the
machine enters the toner supply mode after the job.
The above detection is carried out while the development clutch is activated.
Toner supply mode after the job:
• The development unit with the almost-empty cartridge idles for 40 s.
• Then, it idles again for another 20 s.
• During this 20 s period, the toner end sensor is checked every 10 ms. If a low
toner condition is not detected during this 20 s period, the machine returns to
standby mode after idling all development units for 90 s.
• However, if a low toner condition was detected during that 20 s period, the
machine indicates toner near-end.
SM
CÓPIA NÃO CONTROLADA
[B]
6-31
CÓPIA NÃO CONTROLADA
DEVELOPMENT
[C]
[A]
G070D306.WMF
G071