Controls; Scanner Motor Control; Scanner Drive Control - Canon Color Image Reader - L1 Service Manual

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Technology

Controls

Scanner drive control

Confi guration of drive system
Following is the parts confi guration related with scanner drive system.
Reader controller PCB
Scanner home position
sensor (SR2)
Scanner unit
Component parts Symbol
Scanner motor M1 Control of the drive/stop, direction and speed of motor rotation
Scanner unit HP sensor SR2 Scanner unit HP detection
Scanner unit - Image reading, analog image processing
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Technology
Scanner motor (M1)
Function

Scanner motor control

Following is the control system confi guration related with the scanner motor control.
Motor driver on the reader controller PCB controls the drive/stop, direction and speed of
scanner motor rotation in accordance with the signals from CPU.
1) Backward operation after image scanning
Backward operation after image scanning until shading position of scanner unit is control-
led by 468 mm/sec regardless of color mode.
2) Forward operation at image scanning
At image scanning, the following motor control controls the scanner unit operation.
Start position Image leading edge
Acceleration Normal speed
Shift
speed
[1] [2]
Shift length
[1] Acceleration Zone: accelerates to suit the selected mode.
[2] Approach Zone: moves for speed stabilization.
[3] Image Read Zone: reads the image at a specific speed.
(if black-and-white/SEND mode, twice as fast as in full-color mode.)
[4] Deceleration Zone: past the image trailing edge, immediately decelerates and stops.
Image trailing edge
Stop
Deceleration
[3] [4]
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