METHOD OF PREPARING A MOLDED ARTICLE

摘要

A method of forming a shaped thermoplastic sheet and apparatus are described. The method includes providing a mold apparatus (1 ) that includes, a first mold portion (11) having an interior mold surface (14) having a plurality of perforations (26) and a perimeter edge (17). The mold apparatus (11) further includes at least one sheet retainer (35) having an upper surface (38) having a plurality of perforations (41 ) and a longitudinal axis (44) that is oriented along at least a portion of the perimeter edge (17) of the first mold portion (11). Each sheet retainer (35) is reversibiy and controllably: (i) positionable along an x-, y- and/or z-axis relative to the perimeter edge (17); and (ii) rotatable around its longitudinal axis (44), toward and/or away from the perimeter edge (17). A heated thermoplastic sheet (95) is formed and contacted (while at a thermoformable temperature) with the interior surface (14) of the first mold portion (11 ) and the exterior surfaces (38) of the tubular sheet retainers (35). Reduced pressure is drawn through the perforations (41 ) of the sheet retainers (35) thereby retaining a portion of the heated thermoplastic sheet (95) thereon.