Dashboard for motor vehicle, has noise absorption unit with wall structure integrated in dashboard, where structure has perforations or micro perforations constituted by holes with specific diameter and slits with specific width and length

摘要

The dashboard (2) has a noise absorption unit including a double wall structure integrated in the dashboard at an upper horizontal part (4) of the dashboard adjacent to a windscreen (1). The double wall structure comprises a perforate and micro perforate upper exterior wall (5) permitting dissipation of acoustic energy and an acoustically sealed plain interior wall (6) spaced of the exterior wall. A set of perforations or micro perforations of the structure is constituted by holes or borings (7) with diameter lower than 3 mm and slits with width lower to 0.5 mm and length lower to 5 mm.