Canon Vizcam 1000, Service Manual

Page: 185 / 840

COPYRIGHT © 2001 CANON INC. CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
3-141
3. OPERATION AND TIMING
d. Detecting the Thickness of Paper
When picking up paper from the multifeeder, the CLC1000 uses the paper thickness detecting roller and
the reflecting type paper thickness sensor in the multifeeder pick-up assembly to check the thickness of
paper; in particular, it controls the fixing speed to ensure proper fixing of images on thick paper.
The paper thickness detecting roller rotates by the drive of the pick-up motor (M10) coming by way of the
paper thickness detecting roller clutch (CL7).
Under the control of the CPU on the DC controller PCB, the light of the LED of the paper thickness
sensor is shone against the paper thickness detecting roller (upper) when paper is not moving through the
paper thickness detecting roller. The difference in the angle of the light of the LED reflected by the paper
thickness detection roller (upper) lets the paper thickness sensor to identify the shift of the paper detecting
roller (upper) caused by the thickness of paper.
The shift is subjected to computation to find out the thickness of paper: ‘roller position when paper is
present’ - ‘roller position when paper is absent’ = paper thickness.
Figure 3-611
Multifeeder relay PCB
Pick-up motor
controller PCB
Paper thickness detecting roller drive signal (CL7D*)
Pick-up motor drive signal (M10D*)
DC controller PCB
M10
Paper thickness
detecting roller
clutch
CL7
Pick-up
motor
Paper thickness
sensor (PTS1)
Paper thickness
detecting roller (upper) LED
Paper thickness detecting roller (lower)
(front)
Photo diode array
Pressure spring
(PTHDT1)
(PTHDT2)
J2207A
-1 J2213A
-9 J2207A
-8 J2207A
-10
Pick-up motor controller PCB