An apparatus and method for forming a design on an expanded bead foam article such as an exercise roller is provided.

A method of manufacturing a footwear sole component is provided including projecting elongated pins into a mold cavity in the shape of the footwear sole component and partially filled with an expandable material including multiple unexpanded beads, and introducing steam into the cavity through ports defined by one or more cavity walls and through the pins in an internal region of the expandable material, to expand both exterior beads and interior beads in the internal region a predetermined amount. With the elongated pins, the interior beads can be expanded more, less and/or the same amount as exterior beads to provide particular physical characteristics to the component. For example, the interior beads can be fully expanded to a similar density as exterior beads, or expanded less to provide more density and rigidity in the internal region, or expanded more to provide less density and rigidity in the internal region.

A process for manufacturing an expanded polystyrene foam article from used expanded polystyrene foam articles in combination with virgin polystyrene foam, the process comprising the steps of: stacking a plurality of individual used expanded polystyrene foam articles in a vertical block machine to occupy at least 20% of the internal volume in the block machine; conveying virgin polystyrene beads into the internal volume of the vertical block machine to occupy at least some of the remaining internal volume of the block machine by mixing the virgin polystyrene with the used stacked foam articles; and heating the internal volume of the block machine to a temperature of at least 75° C. by supplying pressurised steam into the heated internal volume of the block machine to fuse the virgin expanded polystyrene beads and the stacked expanded polystyrene foam articles to form the expanded polystyrene foam article.

A steam chest mold includes two mold sections defining a mold cavity and a plurality of steam tubes having steam ports positioned within the mold cavity. The mold cavity is closable to contain and compress a plurality of beads such as expanded polyolefin beads. The steam tubes pass through the beads such that steam is injected through the steam ports into the beads to facilitate localized melting and bonding o the bead interfaces to produce a water-impervious panel or billet form. The steam tubes permit bonding of interior beads in thick section billets and panels that cannot be accessed by perimeter steam sources.

A method of manufacturing a footwear sole component is provided including projecting elongated pins into a mold cavity in the shape of the footwear sole component and partially filled with an expandable material including multiple unexpanded beads, and introducing steam into the cavity through ports defined by one or more cavity walls and through the pins in an internal region of the expandable material, to expand both exterior beads and interior beads in the internal region a predetermined amount. With the elongated pins, the interior beads can be expanded more, less and/or the same amount as exterior beads to provide particular physical characteristics to the component. For example, the interior beads can be fully expanded to a similar density as exterior beads, or expanded less to provide more density and rigidity in the internal region, or expanded more to provide less density and rigidity in the internal region.

A plastic article is recited having a plastic shell including walls defining a cavity. Within the cavity is an in-situ foam core including expanded polymer beads. A layer of the expanded polymer beads includes a layer of distorted beads adjacent to the walls. The in-situ foam core has a thermal bond to the walls.

A method for producing a skin-covered molded article including filling polypropylene-based resin expanded beads in a hollow space of a thermoplastic resin skin and feeding steam into the hollow space to fusion-bond the expanded beads together, the expanded beads showing specific DSC characteristics involving a specific high temperature peak(s) with specific heat of fusion.

The plastic structural article includes an elongated tubular shell having opposed end sections, a middle section there between and an interior cavity. The interior cavity has a foam core situated therein. The foam core comprises steam expandable polymer beads which when expanded substantially fill the interior cavity. The bead and shell are of a similar plastic composition enabling the articles to be reground and recycled. An apparatus for forming the articles and an associated method of manufacture are also disclosed. A thermal management system includes a panel having a periphery, and a skin having a thermal bond to an in-situ foam core. The panel has a thermal transmittance u-value ranging from 0.1 to 0.17 W/m.sup.2 C.

The plastic structural article includes an elongated tubular shell having opposed end sections, a middle section there between and an interior cavity. The interior cavity has a foam core situated therein. The foam core comprises steam expandable polymer beads which when expanded substantially fill the interior cavity. The bead and shell are of a similar plastic composition enabling the articles to be reground and recycled. An apparatus for forming the articles and an associated method of manufacture are also disclosed.

Proposed are an apparatus and a method for expanded polypropylene (EPP) molding. The apparatus for EPP molding includes an upper mold, a lower mold forming a cavity, which is a space for manufacturing a molded product, together with the upper mold, a skin holding means provided at the upper mold or the lower mold, an insert holding means provided at one of the upper mold and the lower mold where the skin holding means is not provided, a resin supply means supplying a polypropylene resin to the cavity, a heating means applying heat to the polypropylene resin supplied to the cavity, and a mold driving means moving the upper mold and the lower mold in directions towards or away from each other.