CHAPTER 6 IMAGE FORMATION SYSTEM
6-20
COPYRIGHT © 1999 CANON INC. CANON imageRUNNER 400/330 REV.0 JAN. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
C. Controlling Toner Level Detection
A toner sensor of a piezoelectric oscillation type (TS1) is mounted inside the developing
assembly to monitor the level of toner.
When toner exists inside the developing assembly, the output of the toner sensor goes '1'; when
the level of toner drops below a specific value, the output will go '0'.
The DC-CPU on the image processor PCB reads the output of the toner sensor while the
developing clutch (CL4) remains on. It then computes the 0's (most recent two cases) of the toner
sensor output, and indicates the Add Toner message in the touch panel as needed.
Figure 6-202
Developing clutch (CL4)
Check
Toner sensor (TS1)
3 sec
5 sec
2 sec
NG
(11 sec)
OK
(9 sec)
OK
(7 sec)
NG
(82 sec)
When the power switch is turned on,
recovery is made after stirring
the toner for another 30 sec.
When the power switch is turned on/off,
recovery is made after stirring
the toner for 6 sec.
Toner absent level 1
Copying
Fax receive
Fax send
Printer output
No
Yes
Yes
Yes
Copying
Fax receive
Fax output
Printer output
No
No
No
Yes
If the most recent toner absent
periods add up to 10 sec or more,
Toner absent level 2
If the toner absent periods
add up to 80 sec or more,
6 sec
82 sec