Canon 1000 Service Manual page 213

7. Operation of the Transfer Belt Lifter
A mechanism is needed to prevent adhesion of toner on the photosensitive drum to the transfer belt
when the density of Bk toner is measured (See chapter 3. E. Developing Assembly, 4-e. Measuring the
Toner by the SALT Sensor). To prevent adhesion, the drive of the pick-up motor (M10) is transmitted to the
cam through the transfer belt lifter clutch (CL17), thereby lowering (moving away) the transfer belt by the
transfer lifter arm.
When the density of Bk toner has been measured, the transfer belt is moved up back to the point of
transfer.
The lifter movement is monitored with reference to the light-blocking plate (mounted to the cam shaft)
detected by the transfer belt lifter sensor 1 (PS12) and the transfer belt lifter sensor 2 (PS13). (See Table 3-
610.)
If the transfer belt lifter does not reach a specific point over a specific period of time after the transfer belt
lifter clutch has turned on, 'E074' will be indicated on the control panel.
Lifter fulcrum
Drive roller
Transfer belt
COPYRIGHT © 2001 CANON INC.
Photosensitive Photosensitive
drum (Bk) drum (C)
Transfer lifter arm
Light-blocking
plate
Cam
Figure 3-638
CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
Photosensitive
drum (M)
Arm fulcrum
Transfer belt
lifter sensor 1
(PS12)
Transfer belt
lifter sensor 2
(PS13)
Cam shaft
3. OPERATION AND TIMING
Photosensitive
drum (Y)
PS12
Transfer belt
lifter clutch
M10
Pick-up motor
PS13
3-169