Automatic document feeder provided with three movable claws for directing the paper through different paths

An automatic document feeder for an image forming apparatus having an optical exposure portion for performing thereon scanning of a document, comprising:

• first and second document trays each for stacking thereon one or more documents;
• a document feeding means for feeding the documents one by one from the first document tray in order from the uppermost one of the documents, while reversing the same upside down;
• a document conveying means for feeding a document in forward or backward directions along the optical exposure portion;
• a reversing convey means for receiving the document fed from the optical exposure portion and for feeding the same in a first direction toward the second document tray while reversing the same upside down, as well as a second direction opposite to the first direction;
• a first change-over means for selectively connecting the optical exposure portion to the document feeding means for the reversing convey means;
• a second change-over means movable between a first position at which the document fed from the optical exposure portion is led toward the reversing convey means, and a second position at which the document is led toward the second document tray when the document is fed by the reversing convey means in the second direction;
• and
• a third change-over means for selectively leading the document fed by the reversing convey means in the first direction to the second document tray or the optical exposure portion;
• when a two-sided image bearing document is copied, the first change-over means being adapted to connect the optical exposure portion to the reversing convey means, and the third change-over means being adapted to lead the document to the optical exposure portion while the reversing convey means is adapted to feed the document in the first direction, after that, the first change-over means being adapted to be maintained in the selecting position thereof, and the third change-over means adapted to lead the document to the second document tray while the reversing conveying means being adapted to be maintained in the feed direction of the document;
• when a single-sided image bearing document is copied, the first change-over means being adapted to connect the optical exposure portion to the reversing convey means, and the third change-over means being adapted to lead the document to the second document tray while the reversing convey means is adapted to feed the document in the first direction, after that, the second change-over means being adapted to move to the second position and the third change-over means being adapted to be maintained in the selecting position thereof while the reversing convey means is adapted to be changed in the feeding direction to the second direction.