| 摘要 |
PURPOSE:To enable the use of a mold without removing a fin, by performing molding by employing a mold wherein parting lines are meshed and inlaid with the surfaces parallel to the axial line of a fan main body so as to direct a fin in parallel relation to the axial line of the fan main body. CONSTITUTION:In preparing a fan main body 3 as an injection-molded product comprising a plastic material such as polypropylene, a mold 6 is used. This mold 6 is one wherein parting lines 6A, 6B are meshed and inlaid with the surfaces parallel to the axial line of the fan main body 3 and all the fins 5 generated at the parting lines are ones each directed in parallel relation to the axial line of the fan main body 3. Even if the obtained fan main body 3 is directly confronted to the interior of a fan guide without removing the fin 5, it is finished in a dimension same to the outer diameter determined by the mold 6 and a chip clearance can be held to an extremely fine dimension. |
