| 摘要 |
PURPOSE:To surely seal an abutted part without impairing appearance by outside holding the face of a fluorine-based resin film and bending this resin film and allowing the notched sides to abut in such a state that the respective oblique end faces are closely brought into contact with each other and then welding the abutted notched sides inside. CONSTITUTION:A corner part is cut by forming notches that have equilength respectively and cross at 90 deg. from the points (d), (e) on the each end side which are equidistant apart from a corner top part C of a metallic plate laminated by resin. Further the notched sides 3 are formed which have the oblique end faces tilted at 45 deg.. Thereafter the face of a fluorine- based resin film 2 is outside held and the metallic plate laminated by resin is bent at 90 deg.. The notched sides 3 are allowed to abut in such a state that the respective oblique end faces are closely brought into contact with each other. Then the abutted notched sides 3 are heated by flame 4 from the inside and welded. Thereby a welded part 5 is formed in the range over the whole length of the notched sides 3 and the notched sides are completely sealed. When the metallic plate is bent and two notched sides are allowed to abut, the oblique end faces are closely into contact with each other. Therefore even when flame 4 is blown up from the inside at a time of welding, the fluorine-based resin film 2 can be prevented from being discolored because flame 4 is infiltrated to the outside through the interval of two notched sides 3. |
