| 摘要 |
PURPOSE:To eliminate the development of stress concentration round the neighborhood of a cavity and consequently contrive to improve the quality of the resultant molded material by a method wherein a travelling piece having a material bunghole is provided on either a fixed retainer plate or on a movable retainer plate so as to wander the material bunghole toward the surface of the cavity at the filling process of molding material. CONSTITUTION:On either a fixed retainer plate 2 or a movable retainer plate 3, a slider 10 as travelling piece is provided. In addition, on the slider 10, a gate part 11 as resin bunghole is provided. Any slider 10 may be allowed as long as it has the structure, with which the gate part 11 can be wandered toward a cavity. A pair of guide pieces 13 extending like wings at the lower sides of the slider 10 are provided, resulting in constituting so as to guide a pair of guide grooves 14 on the fixed retainer plate 2. Further, by assembling bearings with the guide pieces 13, frictional resistance can be reduced. The slider 10 is moved from one of its widthwise side with a driving means 15. Thus, the material bunghole is wandered to the cavity, resulting in preventing the stress concentration from occurring. |
