| 摘要 |
PURPOSE:To prevent generation of a weld by making an injection flow velocity of a resin material uniform, by providing a thin part whose thickness is specific on a thick part of a molded article. CONSTITUTION:In relation to a cross-sectional area S in a general surface 3 of a molded article 1, a cross-sectional area S1 in a rib 2 and a cross-sectional area S2 in the edge part side of the rib 2, the S2 which is a thin part and satisfies a relation of S1/2<=S2<=S is formed. As a flow velocity 4 of a material to be injected to the thick part S1 becomes close to that of the general surface 3 as per a broken line by the thin part S2 at the time of injection molding and the flow velocity becomes uniform by varying liquid resistance at both parts, generation of weld at a confluent part of the material is prevented. In addition to the above, as a thickness difference of the material can be varied by making a quality of the synthetic resin molded article constant always, design properties and strength can be varied freely. |
