Sharp AM-900 Service Manual page 55

7.9. Switching operation (1) from the fixed scan mode to the sheet scan mode
Sheet scan drive side gear train
Scan unit drive side gear train
Planet gear B
System gear biasing spring
When the scan unit's lever that comes back to the sheet scan position
pushes the system gear pin, the system gear starts rotating in clock-
wise direction.
7.10. Switching operation (2) from the fixed scan mode to the sheet scan mode
Scan unit drive side gear train
Planet gear B
Due to the system gear rotation, the pin B on the planet gear mounting
arm is guided in the cam groove B, and the planet gear B is engaged
with the system gear. Along with the system gear rotation, the scan
unit locking lever moves toward the lock position.
Planet gear A
Sheet scan drive side gear train
Planet gear A
Pin A
Cam groove A
System gear biasing spring
Pin
Motor gear
(drive source)
Counterclockwise rotation: The scanner
unit moves toward the sheet scan position.
System gear
Pin
Scan unit locking lever
Motor gear
(drive source)
Counterclockwise rotation: The scan
unit moves toward the sheet scan position.
Cam groove B
Pin B
System gear
Lever
Scan unit locking lever
3 – 8
Scanner unit
Lever
Scanner unit
AM-900U