VACUUM MOLD AND DEVICE FOR DRILLING EXTRACTION HOLES THEREIN

摘要

A vacuum mold includes a mold body with a molding surface. The mold body defines a plurality of extraction holes. Each extraction hole includes a first hole portion, a second hole portion, and a connecting portion connecting the first hole portion and second hole portion. The first hole portion is adjacent to the molding surface, and a diameter of the first hole portion is smaller than a diameter of the second hole portion.