Active tyre or road surface noise reduction device for automobile uses capacitive sound sources within wheel housing for active compensation of detected noise

摘要

The noise reduction device uses an active capacitive sound source (7,17) at one or both sides of the wheel housing (3), incorporating a noise detector (9,15) coupled to an electronic control device (1,6), supplying a signal to the sound source via an intermediate amplifier (2,5). The sound sources are made of a water-proof material, or coated with a water-proof material.