| 摘要 |
<p>An assembly disposed within a mold for forming openings in a plastic part includes a punch pin (32) and a backing pin (22) having faces disposed flush with a surface of a mold cavity (20). The backing pin (22) is disposed opposite the punch pin (32). The punch pin (32) is driven into the completed plastic part removing material to form an opening. The waste material is driven into a bore (30) housing the backing pin (22). The backing pin (22) recedes into the bore (30) to accept the waste material. Upon ejection of the plastic part the waste material ejects from the mold cavity (20) as the backing pin (22) moves back to a position flush with the surface of the mold cavity (20).</p> |
