Canon DADF-AG1, Service Manual

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Technology > Controls (DADF) > Document Pickup/Separation > Basic Pickup Operation
Technology > Controls (DADF) > Document Pickup/Separation > Basic Pickup Operation
Document Pickup/Separation
■ Basic Pickup Operation
With a document placed on the document tray, pressing the print start key will pick up the
document in the following manner.
Pickup operation
When the pickup/feed motor (M1) turns in reverse direction, the pickup roller unit lowers to
rotate the pickup rollers, thus feeding the document.
The stopper rises in conjunction with the pickup roller unit.
The separation sheet and pad are used to prevent multiple sheets from being fed together.
CL1
M1 M1
CL1
Document
Pickup roller unit
Stopper Separation sheet Separation pad
Pickup roller unit
Formation of loop
While the pickup/feed motor (M1) is turning in the reverse direction, the document is fed
against the stationary registration roller to form a loop because the registration clutch is not
driven, thus preventing the document from skewing.
Formation of loop
Registration roller
F-2-11
F-2-12
Feed
The pickup/feed motor (M1) turns in the reverse direction to drive the registration clutch (CL2),
thus allowing the registration roller to feed the document.
The read roller feeds the document to the read wait point.
When the document reaches the read wait point, the pickup/feed motor (M1) stops.
Read roller 1
Read wait point
Registration
roller
CL2
M1
Stream reading
When the leading edge of the document reaches the reading point, an image leading edge
signal is sent to the host machine to start stream reading.
"Stream reading" is a scan mode in which a document is moved on the optical system's glass
using the platen roller.
The read image is stored in the memory of the host machine.
Platen roller
LED
Read roller 2
Read glass
M1
F-2-13
F-2-14