METHOD AND APPARATUS FOR BLOW MOLDING HOLLOW ARTICLES

摘要

A method and apparatus for blow molding plastic articles which utilizes one or more fixed needles and one or more micro vents associated with a blow mold c avity. Each needle has a first passage associated therewith through which vacuum is supp lied to pull the molten plastic about the needle and a second passage therein through which a ir under pressure is introduced to tear the plastic and blow the article to the confines of th e mold which has been closed about the plastic parison. Micro vents facilitate exhausting air whi ch is about the parison. Preferably the second passage for compressed air is provided by a central bo re and the first passage for the vacuum is provided by an annular space about the fixed needl e. In a modified form, the fixed needle comprises dual air passages. Provision is made for ut ilizing plural molds with controls for supplying air and vacuum.