Patent ID: 7608318

Claim:
A sandwich panel, comprising: two skins; and a zigzag corrugated core having alternating protrusions and recesses extending between the skins and connected to the skins by an adhesive composite material, wherein the core is a folded core made from a sheet blank with protrusions zigzag bending lines, recesses zigzag bending lines, and saw-tooth bending lines crossing the zigzag bending lines, plane slanting sides of the folded core are connected to each other along the protrusions zigzag bending lines and the recesses zigzag bending lines by curvilinear parts whose folded core radius along the zigzag bending lines is not less than a core material sheet blank thickness, perforation lines provided along the zigzag bending lines enable penetration of the adhesive material through holes of the perforation lines and into crimps, and the adhesive material forms a head and body of a rivet in the crimps during assembly of the core and the skins.