US Patent 10124555 Sandwich structure including grooved outer sheet

A sandwich structure employs a core sheet including alternating peaks and valleys therein, and at least one outer face sheet including grooves or ribs therein. In another aspect, a sandwich structure includes at least one core and at least one adhesively bonded outer face sheet including elongated grooves or ribs formed therein. Yet another aspect of a sandwich structure has raised ridges bridging between adjacent peaks in a core sheet in one direction but not in a perpendicular direction, which synergistically interface, engage or contact with grooves or ribs formed in an outer face sheet.