| 摘要 |
PURPOSE:To contrive to produce a weldless rib in a hollow molded article by a method wherein thermoplastic resin is injected in a cavity and, after that, gas is poured from positions, which locate apart right and left from a gate, so as to produce the rib in the interior of the hollow molded article corresponding to the position of the gate. CONSTITUTION:A hollow molded article 1 for forming an assistant grip is produced by the resin injected through a gate 2. After that, gas is poured through gas bung holes 5 locating at positions, which locate apart right and left, so as to produce hollow parts 4a and 4b right and left and, at the same time, a rib 6 is produced between the hollow parts 4a and 4b at the position corresponding to the gate 2. Thus, since the rib 6 is produced at the position correspondent to the gate 2, the weldless rib 6 can be produced. |
