Roller leveler and plate flattening method using the same

摘要

A roller leveler includes: a leveling roll unit having a plurality of leveling rolls configured to rotate so as to pass a plate while sandwiching and pressing the plate; a pushing cylinder provided at each of an entrance side and a discharge side of the leveling roll unit, at which the plate enters and is discharged, respectively, and configured to press the plate via the leveling rolls; and a driving mechanism configured to rotate the leveling rolls to pass the plate. At least one of the plurality of leveling rolls has a stepped structure, including a lateral center portion with a large diameter, corresponding to a center portion of the plate with respect to a plate width direction, and lateral end portions with a small diameter, corresponding to edge portions of the plate with respect to the plate width direction.