Device for reducing tire/road surface noise

Abstract

A device for reducing certain sound ranges of tire/road surface noise of a motor vehicle includes sound absorbers in the form of resonators positioned at the inner wall of a wheel well of the vehicle in the area of sound projection of the tire/road surface noise. The device has an electronic control device for receiving a signal preferably derived from an ABS system in the form of the wheel rpm. The control device adjusts the resonators according to the number of tread blocks of the tire, the sound emission characteristics, and the wheel rpm. In another embodiment the electronic control device is supplied with signals received from a sound receiver that records the course over time of the sound pressure. The control device adjusts the resonators such that the measured sound pressure signal is minimized. In another alternative the device has a data processing unit including an electronic control device. The control device is supplied with a signal from sound receiving devices that record the course over time of the sound pressure. The data processing unit together with an adjusting device adjusts the resonators such that the measured sound pressure signal for selected frequency ranges is minimized.