IMAGE READING DEVICE AND IMAGE FORMING APPARATUS THEREWITH

摘要

An image reading device has an optical unit, a pair of rail portions, and a driving device. The optical unit reads an image on the document. The pair of rail portions support the optical unit such that this is slidable in the sub scanning direction. The driving device enables the optical unit to move in the sub scanning direction. The driving device engages with the optical unit substantially at the position of its center of gravity in the main scanning direction, and the pair of rail portions are arranged one on each of one and the other sides in the main scanning direction so as to be equidistant from the position of the center of gravity.

主权项

1. An image reading device comprising:
a contact glass on which a document is placed; an optical unit arranged under the contact glass, the optical unit being scanned in a sub scanning direction to read an image on the document placed on the contact glass; a pair of rail portions extending in the sub scanning direction, the rail portion supporting the optical unit such that the optical unit is slidable in the sub scanning direction; and a driving device which enables the optical unit to move reciprocally in the sub scanning direction, wherein the driving device engages with the optical unit substantially at a position of a center of gravity thereof in a main scanning direction, and the pair of rail portions are arranged one on each of one and another sides in the main scanning direction so as to be equidistant from the position of the center of gravity.