图1是玩具吉普车身的简图。由图可见,沿俯视图的法线方向上有较大空腔,即可定为模具的开模方向。但从其主视图又可看出,车身最大轮廓线的侧向呈曲线形状,从而也就决定了所设计的注塑模必然为曲面分型模具。 Figure 1 is a schematic view of the toy Jeep body. As can be seen from the figure, there is a large cavity along the normal direction of the top view, which can be set as the mold opening direction. However, from its main view, it can be seen that the lateral profile of the largest outline of the car body is in the shape of a curve, which also determines that the designed injection mold must be a mold for the surface sub-type.