Belt conveyance apparatus and image forming apparatus using such a belt conveyance apparatus

An image forming apparatus comprising:

• image forming means for forming an image;
• and
• a belt conveyance apparatus including:
• a drive roller;
• a driven roller rotating in accordance with an operation of the drive roller;
• a conveyance belt engaged with the drive roller for rotationally driving the conveyance belt and the driven roller, the conveyance belt being provided with a first bead and a second bead formed on an inner side thereof;
• and
• driven roller support means for rotatably supporting the driven roller, the driven roller support means being configured to allow the driven roller to move in a thrust direction,
• wherein, in operation, ends of the drive roller and the driven roller interface with the first bead and second bead of the conveyance belt so as to allow and restrict a deflection of the conveyance belt in the thrust direction, and the driven roller is movable in the thrust direction according to a deflection of the conveyance belt, and
• wherein a frictional force in the thrust direction between the driven roller support means and the driven roller is smaller than a frictional force of the driven roller and the conveyance belt.