Canon Image Reader-A1, Service Manual

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COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON iR5000i/iR6000i REV.0 JUNE 2001
CHAPTER 5 PICK-UP/FEEDING SYSTEM
5-17 P
2.3 Identifying the Size of Paper in the Cassette
2.3.1 Right/Left Deck
The right/left deck does not possess a paper size detection mechanism, and its size con-
figuration is changed as follows (A4, B5, LTR):
[1] Changing the position of the paper size guide plate of the cassette.
[2] Registering the new paper size in service mode.
COPIER>OPTION>CST>P-SZ-C1
right deck paper size
Settings:
6: A4; 15: B5; 18: LTR
COPIER>OPTION>CST>P-SZ-C2
left deck paper size
Settings:
6: A4; 15: B5; 18: LTR
2.3.2 Cassette 3/4
a. Outline
The size of paper inside the cassette is identified by the paper size sensor mounted to the
rear of the cassette holder.
When the cassette is slid into the cassette holder, the paper size sensor is activated by the
boss on the cassette, enabling the identification of paper width and length. Based on the
width and the length, the DC controller identifies the size of the paper, and sends the result
to the controller unit and the reader unit.
The boss used to press the paper size sensor operates in conjunction with the guide plate
inside the plate, i.e., its position is determined when the guide plate is set to suit a particular
paper size.
The cassette 4 of the 120/230V model, however, is not equipped with a paper size detec-
tion mechanism, requiring switching of the paper size.
b. Identifying the Size of Paper
The paper length sensor consists of two photointerrupters, and the combination of outputs
from these two photointerrupters is used to find out the length of paper.
The paper width sensor, on the other hand, is a variable resistor, and the resistance it reads
is used to find out the width of paper.