| 摘要 |
PURPOSE:To display a larger silencing effect of noise, by forming many passages of honeycomb state with a plate material of aluminum foil or the like, adhesively gluing a plate or grain shaped noise silencing material of ''Moltopren '' or the like to an internal face of said passages and increasing a number of ventilating passages and their diameter. CONSTITUTION:Polygonal ventilating passages 5, in which a plural sheets of metallic foil materials 1 of aluminum foil or the like are suitably jointed to concurrently form many passages toward the longitudinal direction, are provided, and the many passages 5 are formed to a honeycomb shape as viwed from an end face crossing at a right angle. Then a plate or grain shaped noise sliencing material 2 of ''Moltopren '' or the like is glued to the inside of said passage 5. Further the metallic foil material 1 may be replaced with a plastic sheet or thick sheet of paper. |
