Canon DADF-R1, Service Manual

Page: 73 / 222

Chapter 3
3-15
The registration roller clock sensor (PI5) is used to measure the length of originals with reference to the
revolutions made by the clock plate mounted to the slave roller of the registration roller. Based on the
revolutions of the lock plate, the ADF controller PCB identifies the length of the original in question (in feeding
direction).
F-3-17
The DADF uses the data on the width and the length of the original obtained by original detection 2 to identify
a default size, and sends the result to the copier. In response, the copier selects the appropriate copy paper size
to suit the identified size of the original.
The following tables show the default sizes in relation to the sizes detected by the DADF:
T-3-4
A- and A/B-Configuration
T-3-5
(unit: mm)
Default size Original length Original width
B5R 237 to 297 180 to 184
A5 128 to 188 208 to 212
A4R 277 to 317
FOOLSCAP 317 to 370
B5 162 to 222 255 to 259
B4 344 to 404
A4 190 to 250 295 to 299
A3 400 to 460
A size outside of the above ranges will be identified as a non-default size.
ADF controller PCB
Slave roller
Registration roller
Clock plate
Registration roller
clock sensor (PI5)
TRCLK