Molding apparatus for expanding beads of polystyrene material
AssigneeMansonville Plastics Limited
InventorsRichard N. Roy, Clerval Labbe, Albert Korman
Life of this patent
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Abstract
An improved molding apparatus for expanding beads of polystyrene material into large blocks in the manufacture of insulating material. The mold apparatus has walls made from a plurality of tubular wall members arranged in horizontal, side-by-side relation. The wall members are mounted transversally within encircling frames. Steam is supplied to each wall member, and from within each wall member, into the mold cavity to expand the polystyrene beads held therein into a block. An improved device is also provided to remove the block from the mold cavity.
Claims12
In an apparatus for molding large blocks of expanded thermoplastic material, said apparatus comprising:
- a plurality of walls that together form a mold defining a mold cavity, at least some of said walls being hollow and having interiors connected to the mold cavity by means of a plurality of openings,
- means for filling up said mold cavity with beads of material to be molded, and
- means for supplying steam to the interiors of said hollow walls and from within said hollow walls through the openings into the mold cavity, to heat said beads of material to be molded and cause them to expand and coalesce, wherein:
- each of said hollow walls comprises a plurality of elongated, tubular wall members each having inner and outer walls, said wall members being arranged side-by-side with their inner walls aligned to form together the mold defining the mold cavity,
- said means for supplying steam comprises means for distributing said steam into each of said tubular wall members,
- each of said wall members has a plurality of fins extending along, and projecting inwardly from its inner wall to stiffen said inner wall, to improve heat transfer and to create a plurality of independent sub-chambers in which any condensate may be trapped, said wall openings being located between some of said fins to distribute in turn the steam from within said member into the molding cavity,
- each of said wall members also has means projecting from its outer wall for transversely mounting it onto spaced apart frames which permanently encircle the mold,
- each of said frames comprises at least two frame members and means for movably connecting said frame members together so that said frame members may slightly move away from a molding position where the wall members mounted onto said frame members together form the mold, to a block removing position where part of said wall members separate from the molded block to facilitate its removal from the mold, and vice versa, and
- said means for filling up the molding cavity with beads of material to be molded comprises:
- duct means for directing said beads of material to be molded from a storage area to at least two spaced-apart inlets in one of the walls of said mold,
- blower means in the duct means for moving the beads from said storage area to the molding cavity, and
- means for closing each inlet after the mold cavity has been filled up with beads.
Dependencies are inferred from the claim text.