Method for producing a protective sound panel for a motor vehicle

• Main Authors: Crignon, Guillaume, Capron, Christophe, Lemaire, Dominique
• Format: Patent
• Language: English
• Published: 02.02.2021
• Subjects: ACOUSTICS; ACOUSTICS NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING,NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; MUSICAL INSTRUMENTS; PERFORMING OPERATIONS; PHYSICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; SOUND-PRODUCING DEVICES; TRANSPORTING; VEHICLES IN GENERAL; VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISEPROVIDED FOR; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

The invention relates to a method for producing a protective sound panel for a motor vehicle. The method involves producing a complex including a fibre-based porous back layer, an intermediate layer of shredded recycled material, and a porous front layer, placing the complex in a thermoforming mould to produce a three-dimensional shell, placing the shell in an RIM mould and injecting a foam precursor mixture in order to form a sealed acoustic insulation barrier the binder being incorporated into the front layer. The front layer having a mass per unit area of between 500 and 2000 g/m2, and at least one lightly compressed, high-absorption region with a thickness of between 4 and 10 mm, the minimum total percentage of the lightly compressed region being 40%.