Acoustic insulation barrier e.g. for motor vehicle bulkhead has air impermeable layer and air gap formed by supple blocks

摘要

The insulation barrier consists of a layer of an acoustically absorbent material (16), a layer (17) of a material which is impermeable to air, such as an elastomer, bitumen or felt, and an air gap (19) formed by blocks between it and the insulated panel (15). The air gap is between a few millimetres to a few centimetres wide, e.g. 20 mm, and is formed by spacer blocks (18) e.g. of an elastomer material.