Service manual

TONER SUPPLY UNIT
2-H-2
2 UNIT EXPLANATION
*2 Toner cartridge
When the toner cartridge rotates, toner is fed to
the outlet of the cartridge through the spiral
groove on the surface of the toner cartridge.
When the outlet of the cartridge faces downward,
toner flows out of the outlet into the agitation/sup-
ply section of the toner supply unit.
[3] Toner Level Detection Control
Toner level detection is controlled by the TLD (toner
level detection) and the PRCB (printer control board).
When the front right or left door of this machine opens
or closes, MS1 (interlock 1) or MS2 (interlock 2) oper-
ates to interrupt the DC power supply to the moter,
stopping M5 (toner supply 2).
1. Operation
a. Toner level detection
A piezoelectric device is used as the TLD.
When the level of toner in the cartridge becomes
low, the toner supply signal is output to the
PRCB. As a result, a message is displayed on
the LCD connected to the OB1 (operation board
1).
b. Detection timing
The detection timing is as follows:
•Power-on
• When the front door opens or closes
• During copying
c. Toner supply to toner supply unit
When the no toner state is detected by TLD, M15
(toner supply 2) is turned ON to supply toner from
the toner cartridge to the toner supply unit.
d. Detection of no toner state in toner cartridge
If the level of toner is not detected by TLD after
M15 has been held ON for a specified period of
time, the toner cartridge is assumed to be empty.
A
A
B
B
C
C
Outlet
90° rotation
To agitation/conveyance
block of toner supply unit
TLD CONT
TLD
SGND
12VDC
SGND
24VDC
PGND
PRCB DCPS1
DCPS2
TLD
M15CONT
M15EM
M15CLK
5V
M15
MS2
MS1
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