Patent ID: 7533882

Claim:
An automatic document feeder comprising: a sheet input structure placing thereon a document; a transfer path including a sheet input port, a sheet ejecting port and a scan region, said sheet input port being communicated with said sheet input structure; a first guiding path having a first port connected to said transfer path by a first junction; a second guiding path having a first port connected to said transfer path by a second junction; first and second temporary receiving paths arranged adjacent to a second port of said first guiding path and a second port of said second guiding path for temporarily receiving said document, wherein said document received in said first temporary receiving path or said second temporary receiving path is transported into said first guiding path with a first surface of said document facing to a first direction or a second direction, said second direction being opposed to said first surface; a first guiding unit arranged adjacent to said second port of said first guiding path and said second port of said second guiding path and disposed between said first temporary receiving path and said second temporary receiving path, said first guiding unit including a first guiding strip and a second guiding strip and selectively switched between a first position and a second position to have said first temporary receiving path or said second temporary receiving path communicated with said first guiding path and said second guiding path, wherein a first end of the first guiding strip is pivotally coupled to the position between said second port of said first guiding path and said second port of said second guiding path, a second end of said first guiding strip is sustained against said second guiding strip under said first guiding strip and synchronously shifted with said second guiding strip, said document in said second guiding path is guided by said second guiding strip to be transported into said first temporary receiving path or said second temporary receiving path, and said document received in said first temporary receiving path or said second temporary receiving path is guided by said first guiding strip to be transported into said first guiding path, wherein a first end of said second guiding strip is pivotally coupled to the position under said second port of said second guiding path such that said second end of said first guiding strip is sustained against said second guiding strip, and a second end of said second guiding strip is selectively communicated with said first temporary receiving path or said second temporary receiving path; and a second guiding unit pivotally coupled to said second junction and selectively switched to render or interrupt communication between said second guiding path and said transfer path such that said document passing through said scan region is transported into said second guiding path or transported to said sheet ejecting port.