Paper sheet conveyance apparatus and image forming apparatus

A duplex image forming apparatus, comprising:

• an image forming section to form a first image and a second image on an obverse surface and a reverse surface of a paper sheet, respectively;
• and
• a paper sheet re-feeding section that turns the obverse surface of the paper sheet, on which the first image is already formed by the image forming section, to the reverse surface, and then, feeds the paper sheet again into the image forming section, so that the image forming section can form the second image on the reverse surface of the paper sheet;
• wherein the paper sheet re-feeding section includes:
• a pair of conveyance rollers to convey the paper sheet;
• and
• a stepping motor to drive one of the pair of conveyance rollers;
• and
• wherein at least one of the conveyance rollers is a roller made of aluminum alloy metal;
• and
• wherein the stepping motor is operable to rotate the conveyance rollers in both a normal direction and a reverse direction so that the pair of conveyance rollers are operable to convey the paper sheet in both a forward direction and a backward direction.