Composite cores and panels
A composite core panel has opposite side surfaces for receiving skins to form a composite sandwich panel. The core panel includes a plurality of spaced blocks of low density cellular material such as foam plastics and have opposite side surfaces forming the side surfaces of the core panel and opposite edge surfaces extending between the side surfaces. A plurality of parallel spaced elongated primary strips of structural cellular material such as balsa wood or engineered foam have a higher density and extend between the blocks, and the blocks have side surfaces adhesively attached to edge surfaces of the blocks. A plurality of parallel spaced secondary strips of structural high density cellular material such as balsa wood or engineered foam extend transversely to the primary strips and have end surfaces adhesively attached to the primary strips and side surfaces adhesively attached to the blocks.
1. A composite core panel having an upper core surface and a lower core surface comprising:
a plurality of six-sided blocks of cellular material, and wherein each block has an upper surface facing the upper core surface of the core panel, a lower surface facing the lower core surface of the core panel, and four side surfaces extending between the upper surfaces and the lower surfaces of the blocks,
a plurality of elongated primary strips of structural cellular material having a density greater than the density of the cellular material of the blocks, wherein the elongated primary strips have a pair of side surfaces, a pair of to surfaces, and a pair of end surfaces, wherein the primary strips are arranged such that the side surfaces of the primary strips are adjacent the side surfaces of the blocks and the to surfaces of the primary strips face the upper core surface and lower core surface of the core panel, wherein the top surfaces of the primary strips are flush with the upper and lower surfaces of the blocks,
a plurality of elongated secondary strips of structural cellular material having a density greater than the density of the cellular material and extending in a transverse relationship to the primary strips, wherein the secondary strips have a pair of side surfaces, a pair of to surfaces, and a pair of end surfaces, wherein the end surfaces of the secondary strips are adjacent the side surfaces of the primary strips, and wherein the side surfaces of the secondary strips are adjacent the side surfaces of the blocks; and
adhesive located between and adhesively attaching the side surfaces of the blocks and the side surfaces of the primary strips, between the side surfaces of the blocks and the side surfaces of the secondary strips, and between the end surfaces of the secondary strips and the side surfaces of the primary strips.
2. The core panel of claim 1 , wherein the primary strips and the secondary strips comprise balsa wood.
3. The core panel of claim 1 , wherein the primary strips and the secondary strips comprise a structural plastics foam material.
4. The core panel of claim 2 , wherein each of the strips of balsa wood has end grain extending between the end surfaces of each strip.
5. The core panel of claim 1 , wherein the blocks further comprise grooves which extend from the upper surface of the block to the lower surface of the block.