Sound-eliminating board

Abstract

A sound-eliminating board including sequentially bonded sound transmissible top layer, rigid sound-eliminating middle layer, and elastic sound-eliminating bottom layer. The sound transmissible top layer allows sound waves to penetrate through it into the rigid sound-eliminating middle layer, which includes a plurality of checkered partitions to define a plurality of open-topped small compartments. Sound waves penetrated into the rigid sound-eliminating middle layer reflect repeatedly in the small compartments to result in energy dispersion and counterbalanced energy due to overlapped amplitude of reflected sound waves, and are finally eliminated. In case of any residual low-frequency sound waves that penetrate through the rigid sound-eliminating middle layer into the elastic sound-eliminating bottom layer, they are further eliminated in the bottom layer.

What is claimed is:  
     
         1 . A sound-eliminating board comprising a sound transmissible first layer and a rigid sound-eliminating second layer bonded together to form an integral unit; said sound transmissible first layer being a decorative layer permitting sound waves to penetrate through it into said rigid sound-eliminating second layer, and said rigid sound-eliminating second layer including a plurality of checkered partitions that together define a plurality of small and open-topped sound-eliminating compartments on said second layer.  
     
     
         2 . The sound-eliminating board as claimed in  claim 1 , wherein said sound transmissible first layer is made of a rigid material and provided with a plurality of densely distributed tiny holes.  
     
     
         3 . The sound-eliminating board as claimed in  claim 1 , wherein said sound transmissible first layer is made of gas-permeable non-woven fabrics.  
     
     
         4 . The sound-eliminating board as claimed in  claim 1 , wherein said sound-eliminating compartments on said rigid sound-eliminating second layer have a uniform depth.  
     
     
         5 . The sound-eliminating board as claimed in  claim 1 , wherein said sound-eliminating compartments on said rigid sound-eliminating second layer have different depths in randomly assigned areas.  
     
     
         6 . The sound-eliminating board as claimed in  claim 1 , further comprising an elastic sound-eliminating third layer bonded to a lower side of said rigid sound-eliminating second layer opposite to said first layer, and said elastic sound-eliminating third layer including a plurality of densely distributed internal pores.