| 摘要 |
PURPOSE:To enable to thermoweld a portion only necessary between the skin of a strut main body and a cap without using a special heating device by a method wherein the end of the strut main body is inserted in the recess of the cap made of synthetic resin molding and the cap and the strut main body are rotated relatively. CONSTITUTION:In case that both the skin 3 of a strut main body 4 and a cap 5 are formed of synthetic resin such as polyethylene, when the rotational speed of the cap 5 is set 2,000-20,000rpm, the cap 5 and the skin 3 are instantaneously (within one second) welded together thermally and made into an integral body through the vanishing of their boundary surfaces S. Even in case that the skin and the cap are formed of different kinds of synthetic resin, the thermowelding between the skin and the cap is possible as long as the synthetic resins are compatible with each other. The cap 5 must be held by a rotating adapter or the like. At the same time, the strut main body 4 must be pinched by a chuck or the like. Further, the core material 1 of the strut main body 4 serves for retaining the shape of the skin 3 even when the skin 3 is softened by fric tional head. |
