摘要 |
A first rack of a pair of document guides slides in pressing contact against a pinion due to contact with a protrusion. As a result, the first rack is subjected to a larger sliding resistance than when the protrusion is not provided. When one of the document guides is operated, the operating force transmits directly to the first rack. Therefore, if a large force corresponding to the sliding resistance increased by the protrusion is applied, the first rack can be slid. When the other document guide is operated, the operating force transmits to the first rack through the pinion. Therefore, the sliding resistance increased by the protrusion increases due to the gear efficiency of the pinion. |