| 摘要 |
PURPOSE:To make it possible to obtain excellent sound insulation effect by partitioning a sound insulation panel into partitions more than two based on sound volume penetrating into a cabin from an engine room and the outside of an automobile, and changing the panel in thickness by area. CONSTITUTION:A sound insulation panel 12 is partitioned into four areas, and when the sound insulation panel 12, the surface density of which is changed by area, is mounted onto a dash panel 11, out of noises penetrating into a cabin R from an engine room E, one coming out of a dash floor panel 11b is greatest in degree, bit sound volume penetrating a dash upper panel 11a is comparatively small since it has been damped within a cowl box 14. Similarly, one coming out of a dash floor panel 11c is small in comparison with one coming out of the panel 11b since noise from the engine room E is propagated out of an automobile once, then, it penetrates into the cabin R again, and the same thing can be said of a wheel house section. The surface density of the panel 12 by area is thereby established based on the sound volume penetrating the panel 11 so as to obtain valid sound insulation effect for eliminating waste in material. |
