| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve impact resistance and shape accuracy of a molding, allowing a runner part to be easily removed from a molding body part, and preventing chipping and cracking of the molding body part. <P>SOLUTION: In a molding 1 for injection molding having an annular cavity 5 for forming an annular molding between stacked female and male molds 2 and 3, an annular ring runner 6 provided over the entire circumference along an inner rim of the cavity 5 and an annular gate 7 connecting an outer rim of the ring runner 6 and the inner rim of the cavity 5 over the entire circumference and communicating the ring runner 6 with the cavity 5 are formed between the female mold 2 and the male mold 3. A spool 8 communicating with the ring runner 6 is formed in the female mold 2 or the male mold 3. On a gate-forming mold surface 27 of either the female mold 2 or the male mold 3, an edge 28 protruding toward a gate-forming mold surface 34 of the other is formed over the entire circumference. <P>COPYRIGHT: (C)2012,JPO&INPIT |
