Apparatus for molding expandable polystyrene foam articles

摘要

A device for executing a method of molding expandable thermoplastic polymer beads in a mold to form articles of foamed material comprising: pulsing steam through at least one of the cavities to contact and expand the beads in the cavity for a finite period of time and drawing the steam amongst the beads by providing reduced pressure to at least one of the cavities for the same period of time; and pulsing mist through the expanded beads by providing mist to at least one of the cavities and drawing the mist through the expanded beads by providing reduced pressure to at least one of the cavities for the finite period of time of predetermined duration to form articles of foamed material. The device for molding beads of expandable polystyrene into articles comprises: a mold member mounted to a platen to form a cavity between the mold and platen, core vents formed in the mold, means for introducing steam into the cavity, means for applying reduced pressure to the cavity, and means for introducing mist into the cavity.