Automatic document feeder

An automatic document feeder comprising:

• a platen cover which covers a copying region;
• a document tray which is provided on the platen cover and on which a document fed to the copying region is stacked;
• a pickup assembly which includes a pickup roller that picks up the document stacked on the document tray and transfers the document to a feed path, and a feeding roller that receives the document picked-up by the pickup roller and allows the document to enter the feed path and which pivots the pickup roller centering on a shaft of the feeding roller by a predetermined distance according to a rotating direction of the shaft of the feeding roller;
• and
• a pad holder, including a frictional pad, which is installed in a pad holder groove formed at a region corresponding to the feeding roller in the tray to support the frictional pad installed to contact the feeding roller;
• wherein an opposite portion of the pad holder to a portion supporting the frictional pad is hinge-coupled to the pad holder groove, and a biasing member is installed between a rear side of the pad holder contacting the frictional pad and the pad holder groove to bias the frictional pad towards the feeding roller.