| 摘要 |
PURPOSE:To improve operating efficiency by making weld joining of a vinyle film reliable and smooth, by a method wherein an external circumference of a press roller of a high-frequency sewing machine roll is constituted in a round slice-state, and the central part and the external circumference of the press roller are constituted of at least one or more rollers whose quality of the material is different from that of the press roller. CONSTITUTION:A desired width 26 of the central part of the external circumferential surface 5 of a cylinder of a press roller 1 is surrounded or coated thin and uniformly with a material whose quality of the material is different from that of the central part, for example, with a material of non-polar molecular properties in the desired width 26 inside of an external angle 6 by leaving a predetermined width 25 on the central part. Even if films 13, 14 to be welded move in a zigzag direction independently or simultaneously during welding operation of the films and a side of the films intrudes inward of the roller through the side of the press roller, a spark hole is not generated as a non-polar molecular material has been applied to an inward part of an external angle of the press roller 1, the high-frequency electro-magnetic induction is weak considerably and a spark does not happen. |
