| 摘要 |
<p>PURPOSE:To prevent warp and break due to the difference in expansion and contraction between a reinforcing member and a box by attaching the reinforcing member to the rear of a folded flange except for the four corners and arranging the reinforcing member and the rear of the four corners adjacent thereto at the same surface level. CONSTITUTION:A reinforcing member C is fitted by putting on the upper end of a box molding part A' formed on the molding face E' of a forming mold E for vacuum forming and a flange molding part B'. When the reinforcing member C is fitted on a linear part molding part B'-2, the surface of the reinforcing member C and four corners molding parts B'-1 are set on the same surface level. A synthetic resin material plate D softened by heating is fitted in the forming mold E for vacuum forming with the reinforcing member C fitted thereto, air is evacuated from the forming mold E, and the material plate D covering the reinforcing member C is adhered to the molding face E'. After hardening, the material plate D is demolded and the reinforcing member C is removed from the forming mold E together with a molded body and left on the rear of the flange part B of a box, being the molded form, integrally. The excess part of the material plate D is removed by cutting off at the tip of the rolled-in face B3 of the flange part B.</p> |
