Acoustically absorbent truck tire splash guard

Abstract

An acoustically absorbent truck tire splash guard is mounted behind the tire for absorbing noise generated by the tire. The splash guard includes a face panel which is impervious to damage by particulate matter thrown thereagainst by the tire. The face panel overlies and is juxtaposed with an acoustical foam panel of one to two inches to thickness which is effective to absorb the higher tire noise frequencies, for example, above 1,000 Hz. An array of volume resonators of the Helmholtz type is provided behind the acoustical foam panel. The volume resonators are defined by a resonator panel having a latticework which defines a plurality of cavities. The front of the resonator cavities are closed by a resonator face panel which is juxtaposed with the resonator panel and the acoustical foam panel. Openings are provided in the resonator face panel and communicate with the adjacent resonator cavities. The number or size of the openings in the resonator face panel is varied to tune the resonators over a range of frequencies such as 400, 600, and 800 Hz. so that the array gives nearly uniform noise absorption over the range of noise frequencies which are encountered over a range of vehicle speeds. A back panel is juxtaposed with the back of the volume resonator panel to form the bottom of the resonator cavities and is relatively massive, for example, greater than three pounds per square foot of surface so that it acts as an effective barrier to sound which is not absorbed by the acoustical foam panel or the volume resonators.