13.3 Operation; Toner Replenishing Mechanism/Control - Konica Minolta bizhub C250 Service Manual

Theory of operation ver. 3.0 Aug. 2006

13.3 Operation

13.3.1

Toner replenishing mechanism/control

A. Toner replenishing mechanism
• A single toner supply motor is turned either forward or backward to supply toner of two
different colors (toner supply motor for K and C, and toner supply motor for Y and M).
Toner supply
motor C/K (M7)
Turned forward Energized
Turned backward Deenergized
Toner supply motor Y/M (M6)
• Replenishing operation
1. Drive of the toner supply motor is transmitted through a gear train to the drive gears
of the toner cartridges of two colors. A one-way clutch is used for each of these
drive gears, meaning that the drive gear turns in one direction only. Either one of
these two drive gears is turned according to whether the toner supply motor turns
forward or backward.
2. As the drive gear turns, the screw installed inside the toner cartridge rotates to
transfer the toner to the toner cartridges replenishing port. Then the toner goes
through the carrier pipe of the main body and drops into the imaging unit port to
replenish the supply of toner to the imaging unit.
B. Toner replenishing control
• T/C is detected when the developing clutch/K (CL4) is energized for K or when the color
developing motor (M3) is energized for C, M, and Y.
• Based on T/C ratio detected by the TRC sensor and amount of consumption calculated
by the dot counter, toner replenishing time (amount) is determined.
• When the machine determines the toner replenishing, sometime it detects the toner
amount that surpasses the maximum volume for one replenishing control. If it is not pos-
sible to replenish the supply of the required amount of toner within this maximum replen-
ishing time, the reminder time is stored in memory and added to the replenishing time for
the next replenishing sequence.
K toner C toner
Deenergized
Energized
13. Toner supply section
Toner supply
Y toner
motor Y/M (M6)
Turned forward Energized
Turned backward Deenergized
Toner supply motor C/K (M7)
One-way clutch
M toner
Deenergized
Energized
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