Automatic paper feeder

An automatic paper feeder comprising:

• a pick roller for picking out paper accommodated in a paper cassette and propelling the paper in a paper-feeding direction;
• pick roller driving means for causing said pick roller to rotate to pick paper out of said paper cassette;
• a separation roller for separating multiple sheets of paper picked out of said paper cassette at the same time by said pick roller such that the paper is propelled in the paper-feeding direction one sheet at a time, said separation roller being configured to rotate in the paper-feeding direction when a single sheet of paper is picked out of said paper cassette by said pick roller and to separate multiple sheets of paper by rotating opposite to the paper-feeding direction when multiple sheets of paper are picked out of said paper cassette at the same time;
• separation roller driving means for moving said separation roller into contact with or away from said pick roller;
• a lifter for moving the paper accommodated in said paper cassette into contact with or away from said pick roller;
• lifter driving means for driving said lifter;
• a driving source for driving said separation roller driving means and said lifter driving means;
• and
• control means for controlling said separation roller driving means and said lifter driving means in such a manner as a) to cause said separation roller and the paper to abut against said pick roller when the paper is to be fed;
• and b) to cause said separation roller and the paper to be disengaged from said pick roller when the paper is not to be fed;
• wherein said pick roller driving means and said driving source are independent of each other such that said separation roller and the paper can be moved into contact with or away from said pick roller independently of rotation of said pick roller.