| 摘要 |
<p>Latticed molding grooves (2) are provided in an outlet surface (3) of a die body (7), and a plurality of independent feed passages (5), in the portions of an inlet surface (4) thereof, i.e. the surface opposite to the outlet surface (3), corresponding to the intersecting portions of the molding grooves (2) and extending toward the outlet surface (3). The adjacent feed passages (5) are communicated with one another via through bores (6) at the portions of partition walls of the feed passages (5) via which the feed passages (5) are communicated with the molding grooves (2). Each of these through bores (6) is formed of a combination of a cross-sectionally trapezoidal portion having a lower side 11-12 the length of which is equal to the width of the molding groove (2), and an upper side 13-14 the maximum length of which is equal to the diameter of a feed passage (5), and a cross-sectionally semicircular portion the diameter of which is equal to the length of the upper side 13-14.</p> |
