Brother MFC5490CN Service Manual page 171

Assembling Note: When mounting the lower document chute on the document cover, turn
the planet gear clockwise (viewed from the rear) to put it in the upper position beforehand.
(See the illustration below.)
Viewed from the rear
ADF motor pulley
Planet gear
Sun gear
Separation roller gear
Planetary arm
ADF drive unit
Document feed roller
(Left)
Document ejection roller
Idle gears
(6_26)
Idle gears
6-21
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