Abstract: A fiber reinforced core panel is formed from strips of plastics foam helically wound with layers of rovings to form webs which may extend in a wave pattern or may intersect transverse webs. Hollow tubes may replace foam strips. Axial rovings cooperate with overlying helically wound rovings to form a beam or a column. Wound roving patterns may vary along strips for structural efficiency. Wound strips may alternate with spaced strips and spacers between the strips enhance web buckling strength. Continuously wound rovings between spaced strips permit folding to form panels with reinforced edges. Continuously wound strips are helically wrapped to form annular structures, and composite panels may combine both thermoset and thermoplastic resins.

Abstract: A fiber reinforced core is formed from plastics foam material having elongated porous and fibrous webs and/or rovings extending through the foam material. The rovings may extend angularly through the webs, and strips of the foam material may be helically wound with layers of crossing rovings to form the webs. Porous and fibrous skins for the core may be formed by the wound rovings and by parallel continuous rovings, and the foam strips may be formed with internal grooves adjacent the webs and connected by a feeder channel for infusing a hardenable adhesive resin into the grooves and outwardly through the webs to the skins with differential pressure on the resin.

Abstract: Rigid foam pieces or boards and alternating porous fibrous web sheets are adhered to form core panels or billets. Porosity is maintained in the webs for forming integral structural ties by absorbing resin applied under differential pressure to the webs and to overlying sandwich panel skins. Beveled foam recesses adjacent web edge portions form structural resin fillets, and protruding edge portions form expanded connections to the skins. Core panels with intersecting webs form enhanced panels. Boards or core panels and web sheets arranged in inclined stacks form second core panels having webs intersecting panel edges or faces at acute angles. Boards of alternating different physical properties and web sheets are bonded to form reinforced panels having differing interior and exterior densities. Compressible foam panels are used in place of or with web sheets to make bendable core panels. Foam between web edge portions is recessed for bonding a settable material to the edge portions.

Abstract: Rigid foam boards and alternating absorptive fibrous web sheets are adhered to form core panels or billets. Porosity is maintained in the webs for forming integral structural ties by absorbing resin applied to overlying sandwich panel skins. Beveled foam recesses adjacent web edge portions form structural resin fillets, and protruding edge portions form expanded connections to the skins. Core panels oriented with their webs crossing are layered with web sheets to form enhanced panels. Boards or core panels and web sheets arranged in inclined stacks form second core panels having webs intersecting panel edges or faces at acute angles. Boards of alternating different physical properties and web sheets are bonded to form reinforced panels having differing interior and exterior densities. Compressible foam panels are used in place of or with web sheets to make bendable core panels. Foam between web edge portions is recessed for bonding a settable material to the edge portions.

Abstract: Rigid foam insulation boards and thin flexible fibrous sheets or strips are stacked in alternating layers with adhesive between the layers, and the stack is compressed while the adhesive cures to form a rectangular core panel or billet. In one embodiment, the parallel spaced sheets or strips extend diagonally of the panel or billet, and each billet is cut through the alternate layers of foam and fibrous sheets and along parallel spaced planes to form a plurality of core panels. The core panels are adhesively bonded between skins of rigid sheet materials to form laminated sandwich panels with the fibrous strips connecting the skins. The above stacking and curing steps are also performed with core panels in place of insulation boards to form a billet which is cut to form core panels with grid-like webs, and grid-like core panels are used to form a billet with the webs extending in X-Y-Z directions.