Canon 1000 Service Manual page 199

4. Paper Guide Plate
a. Outline
The paper guide plates are used to control the size of paper to be stacked in the duplexing unit stacking
assembly and to prevent skew movement or jamming during pick-up operation.
The paper guide plates are moved against the edges of paper each time paper arrives.
b. Arranging Sheets by the Paper Guide Plates
When the Start key is pressed while two-sided copying mode is selected, the duplexing stacking guide
motor (M23) starts to rotate counterclockwise, and the paper guide plates move in the direction of the arrows
in Figure 3-625.
The motor stops when the light-blocking plate of the paper guide plate blocks the duplexing stacking
guide home position sensor (PS29).
The DC controller PCB then sends pulses in numbers appropriate to the size of paper to the motor.
In response, the motor starts to rotate clockwise to move the paper guide plate to suit the copy size.
Then, the motor rotates counterclockwise to stop the paper size at a point about 8 mm (each side) away from
the edge of the coming paper.
When the paper arrives at the duplexing unit stacking assembly, the motor rotates clockwise (moving
the guide plate by 8 mm) and counterclockwise (moving the guide plate by 8 mm) to put the paper in position.
When the last paper arrives, the motor rotates clockwise and counterclockwise in preparation for
copying on the second side.
While copying on the second side, the motor remains at rest and remains such until the next run in which
copying on the first side takes place.
Duplexing stacking
guide motor
COPYRIGHT © 2001 CANON INC.
Paper guide plates
PS29
M23
Figure 3-625 Tray (top view)
CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
Counter clockwise
direction
Clockwise direction
Light-blocking plate
Duplexing stacking
guide home position sensor
DC controller PCB
3. OPERATION AND TIMING
3-155