Ventilation duct with noise damping, comprises perforated support, noise damping outer layer and cleanable intermediate layer

摘要

The duct comprises a deformable perforated support (2) that forms the ventilation channel (3) with a given cross-section profile, and a porous noise-damping material (6) surrounding the support. A cleanable non-noise-damping layer (8) is located in between the support and porous material. An Independent claim is also included for a method making the duct.