Device for limiting propagation of acoustic waves emitted by car engine towards cavity of instrument panel, has screen placed in internal cavity to focus acoustic waves, which are likely to traverse acoustic absorption units, towards units

摘要

The device has acoustic absorption units (14, 30) e.g. carpet and heavy mass, firmly connected to a cavity side partition wall. A screen (18) is fixedly placed in an internal cavity (17) to focus acoustic waves, which are likely to traverse the acoustic absorption units, towards the acoustic absorption units. The screen has a concave form with concavity directed towards a noise source e.g. engine (12), where the screen is made of plastic material. The acoustic absorption units include a layer of acoustically absorbing fibrous, porous and/or foaming material. An independent claim is also included for a car.