Panasonic UF-890 Service Manual page 217

Scanner Assembly (340)
The Scanner Assembly consists of two mirrors, a Lens, and a CCD PC Board Assembly (342).
• The mirrors, Mirror 1 (337) and Mirror 2 (338) reflect image information, in the form of light, through the
Lens.
• The Lens focuses the image information and passes it to the CCD.
• The CCD, mounted on the CCD PC Board, converts the image information into an electronic signal.
Drive System
The Drive System uses a Planetary Gear System to provide drive to the Pre-Feed Roller and ADF Roller.
A planetary gear system does not have a fixed position; it shifts its position according to the rotational
torque of the gear, together with the rotation of the planet gear. When the Read Point Sensor is
activated, and the document is scanned, the Pre-Feed Roller and the ADF Roller drive are disengaged.
The Drive System is shown below.
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