| 摘要 |
The present invention comprises a settlement unit, a pre-forming unit, a unit for forming an outer roll, and a unit for forming an inner roll. The settlement unit settles materials to put the edge part of the material toward outside. The pre-forming unit is placed at the side of the settlement unit to move up, and pre-forms the edge part of the material so that the edge part is bent at a certain angle. The unit for forming the outer roll pressures the edge part rolls in contact with the edge part of the material in order that the edge part of the pre-formed material is bent at a right angle. The unit for forming the inner roll is placed at the upper part of the settlement unit to move up. The unit for forming the inner roll supports the upper surface around the edge part of the material and rolls in contact with the inner surface of the edge part of the material. |
