Patent ID: 8903289

Claim:
A belt moving unit comprising: an endless belt member; and a plurality of support rolls that support the belt member movably and that is rotatable, wherein the plurality of support rolls include one or more follower rolls that rotates to follow the movement of the belt member and at least one of the follower rolls is used as an inertial roll to which inertia is applied in a direction in which an amount of inertia increases, wherein the inertial roll includes a rotation shaft that is rotatable, a rotational inertial member that rotates with the rotation shaft and that applies inertia in a direction in which the amount of inertia of the rotation shaft increases, and a roll body that is disposed along a peripheral surface of the rotation shaft and that includes a plurality of roll-divided members formed by dividing the roll body into a plurality of parts in an axis direction of the rotation shaft, and wherein the plurality of roll-divided members include a fixed divided member that is fixed to the rotation shaft and that rotates along with the rotation shaft to follow the movement of the belt member, and a rotating divided member that is rotatable independently of the rotation of the rotation shaft.