ROLL PITCH VARIABLE ROLLER LEVELER

PURPOSE:To enable straightening of a plate from thin one to thick one with one kind of straightening rolls by shifting an upper frame and a lower frame assembling plural straightening rolls and backup rolls as liftable for each to line direction. CONSTITUTION:At the time of straightening the thin material, the backup roll stands are shifted outward to right and left directions with a shift cylinder 5 so that roll surfaces of all straightening rolls face to surface position. By this method, all straightening rolls can be used to the material to be straightened. Further, at the time of straightening the thick material, the backup roll stands are shifted to inward to right and left directions with the shift cylinder 5 so that the straightening roll vertically lifts/lowers to each one piece. By this method, the straightening rolls alternately becomes to recessing and projecting conditions and the straightening rolls are alternately worked as the straightening rolls to the material to be straightened and the other non- working rolls do not contact with the material to be straightened, and even the material having wide roll pitch and thick material can be straightened.