Patent ID: 9099074
Filing Date: 2015-08-04
Classification: B05B,B29C,C08J,E04B,G10K

Abstract:
1. An acoustic insulation for an underlying structure having an underlying structure impedance and a underlying structure surface that oscillates as it emits sound, said underlying structure surface having a mode shape with a plurality of anti-nodes, each of said anti-nodes having a natural frequency, said acoustic insulation comprising: a sprayed-on thermoplastic polymer matrix that is installed on and adheres to the underlying structure; and a plurality of discrete masses that are suspended in said polymer matrix; wherein each of said discrete masses is disposed adjacent to one of the anti-nodes and is tuned to have an impedance that is approximately the same as the underlying structure impedance and that is operative to resonate at the natural frequency of the adjacent anti-node; wherein said sprayed-on thermoplastic polymer matrix is installed using a process comprising: introducing a mixture of a carrier gas, polymer, and blowing agent into an inner chamber of a thermal spray gun; introducing a first gas into an annular region surrounding the inner chamber of the thermal spray gun and introducing the first gas into the inner chamber through a plurality of openings from the annular region into the inner chamber; heating the first gas to yield a heated gas; heating the mixture by mixing it with the heated gas, such that the polymer does not substantially build up on the inner chamber; and spraying the heated mixture onto the underlying structure to form a foam.