PURPOSE: To reinforce a skin member and to suppress cell resonance, by using a foamed plastic as an adhesives which sticks the skin member on the surface of core member made of metallic thin film.
CONSTITUTION: For example, an axially symmetrical honey-comb core 1 having 80mm diameter and 3mm thickness is made of aluminum foil having 20μm thickness and it is formed by extending a honey-comb block through revolution. A skin member 2 made of aluminum having about 20μm thickness is fixed on both sides of the core 1 by using adhesives 4, 5 to form a diaphragm for mediant. A filmlike bonding agent is usd as the adhesive 4 and a foamed polyethylene sheet is used as the adhesive 5. Since foamed polyethylene sheet foams at about 200°C, in the skin member sticking process it foams by clipping, and the thickness of the polyethylene 5 after foaming is about 1mm to increase the bending rigidity of the skin member 2. Thus, cell resonance can be suppressed.
MURATA KOUSAKU
YASHIRO MITSURU
YAMAMOTO TOORU
