Image-forming apparatus with an automatic-document feeder having a document-transporting belt

An image-forming apparatus, comprising:

• a platen on which an original having an original image is placed, the platen being made from transparent material;
• an automatic-document feeder, arranged on the platen, for transporting the original from an original receiving portion onto the platen and for discharging the original from the platen;
• an exposure lamp for exposing the platen to form a reflected light, the reflected light including a light reflected by the original when the original is on the platen;
• and
• an image-forming portion for forming a copy image on an image-bearing member on the basis of the reflected light;
• the automatic-document feeder comprising,
• means for picking up the original placed on the original receiving portion,
• a document-transporting belt, arranged so as to cover the platen, for transporting the original picked up by the picking-up means by contacting an opposite surface of the original which does not face the platen so as to position the original on the platen,
• means for determining that the original picked up has an image on the opposite surface, and
• means for driving the document-transporting belt to transport the original so that a first specific area and a second specific area are formed in the document-transporting belt, the first specific area contacting the opposite surface when the determining means determines that the original has an image on the opposite surface, the second specific area contacting the opposite surface when the original does not have an image on the opposite surface.

An automatic-document feeding method for transporting an original from an original receiving portion to a scanned area in which the original is scanned, comprising the steps of:

• picking up an original placed on an original receiving portion;
• determining that the original picked up has an image on an opposite surface;
• transporting the original picked up using a document-transporting belt so as to position the original on the scanned area, the document-transporting belt being arranged so as to cover the scanned area and contacting the opposite surface during transporting the original;
• and
• driving the document-transporting belt to transport the original so that a first specific area and a second specific area are formed in the document-transporting belt, the first specific area contacting the opposite surface when the original has an image on the opposite surface, the second specific area contacting the opposite surface when the original does not have an image on the opposite surface.

An image-forming method, comprising the steps of:

• picking up an original placed on an original receiving portion;
• determining that the original picked up has an image on an opposite surface;
• transporting the original picked up using a document-transporting belt so as to position the original on a platen made from transparent material, the document-transporting belt being arranged so as to cover the platen and contacting the opposite surface during transporting the original;
• driving the document-transporting belt to transport the original so that a first specific area and a second specific area are formed in the document-transporting belt, the first specific area contacting the opposite surface when the original has an image on the opposite surface, the second specific area contacting the opposite surface when the original does not have an image on the opposite surface;
• exposing the platen to form a reflected light, the reflected light including a light reflected by the original when the original is on the platen;
• and
• forming a copy image on an image-bearing member on the basis of the reflected light.