Sound-absorbing structure using thin film

Abstract

A sound-absorbing structure using thin film of the present invention includes at least a first thin film ( 11 ) and a second thin film ( 12 ), the first thin film ( 11 ) and the second thin film ( 12 ) being layered over each other and one or both of the first thin film ( 11 ) and the second thin film ( 12 ) having at least either ridges or grooves (ridges (a) in the selected figure). As each of the thin films ( 11 ) and ( 12 ), a metallic thin film or a resinous thin film is employable. It is desirable that fine through holes are formed in a large number in the thin films ( 11 ) and ( 12 ).

1 . A sound-absorbing structure including at least a first thin film and a second thin film, said first thin film and said second thin film being layered over each other, and one or both of said first thin film and said second thin film having at least either ridges or grooves.  
   
   
       2 . The sound-absorbing structure according to  claim 1 , wherein through holes are formed in one or both of said first thin film and said second thin film.  
   
   
       3 . The sound-absorbing structure according to  claim 2 , wherein said through holes are formed in both of said first thin film and said second thin film, the through holes formed in said first thin film being formed in positions not overlapping the through holes formed in said second thin film.  
   
   
       4 . The sound-absorbing structure according to  claim 2 , wherein said through holes are fine holes and formed in a large number in said thin films.  
   
   
       5 . The sound-absorbing structure according to  claim 1 , wherein a rear member is installed at a position opposite to a sound wave incidence side with respect to said thin films.  
   
   
       6 . The sound-absorbing structure according to  claim 5 , wherein an air layer is formed between said thin films and said rear member.  
   
   
       7 . The sound-absorbing structure according to  claim 5 , wherein a distance between said rear member and said thin films is adjustable.  
   
   
       8 . The sound-absorbing structure according to  claim 1 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films.  
   
   
       9 . The sound-absorbing structure according to  claim 8 , wherein said front member is formed with a large number of fine holes.  
   
   
       10 . The sound-absorbing structure according to  claim 1 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films, a rear member is installed at a position opposite to said front member with respect to said thin films, and a space between said front member and said rear member is divided into plural portions in the surface direction of said thin films.  
   
   
       11 . A sound-absorbing structure including at least a first thin film and a second thin film, said first thin film and said second thin film being layered over each other, and one or both of said first thin film and said second thin film being folded so as to have mutually contacting and overlapping portions.  
   
   
       12 . The sound-absorbing structure according to  claim 11 , wherein through holes are formed in one or both of said first thin film and said second thin film.  
   
   
       13 . The sound-absorbing structure according to  claim 12 , wherein said through holes are formed in both of said first thin film and said second thin film, the through holes formed in said first thin film being formed in positions not overlapping the through holes formed in said second thin film.  
   
   
       14 . The sound-absorbing structure according to  claim 12 , wherein said through holes are fine holes and formed in a large number in said thin films.  
   
   
       15 . The sound-absorbing structure according to  claim 11 , wherein a rear member is installed at a position opposite to a sound wave incidence side with respect to said thin films.  
   
   
       16 . The sound-absorbing structure according to  claim 15 , wherein an air layer is formed between said thin films and said rear member.  
   
   
       17 . A sound-absorbing structure according to  claim 15 , wherein a distance between said rear member and said thin films is adjustable.  
   
   
       18 . The sound-absorbing structure according to  claim 11 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films.  
   
   
       19 . The sound-absorbing structure according to  claim 18 , wherein said front member is formed with a large number of fine holes.  
   
   
       20 . The sound-absorbing structure according to  claim 11 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films, a rear member is installed at a position opposite to said front member with respect to said thin films, and a space between said front member and said rear member is divided into plural portions in the surface direction of said thin films.  
   
   
       21 . A sound-absorbing structure including at least a first thin film and a second thin film, said first thin film and said second thin film being layered over each other, and through holes being formed in one or both of said first thin film and said second thin film.  
   
   
       22 . The sound-absorbing structure according to  claim 21 , wherein said through holes are formed in both of said first thin film and said second thin film, the through holes formed in said first thin film being formed in positions not overlapping the through holes formed in said second thin film.  
   
   
       23 . The sound-absorbing structure according to  claim 21 , wherein said through holes are fine through holes and are formed in a large number in said thin films.  
   
   
       24 . The sound-absorbing structure according to  claim 21 , wherein a rear member is installed at a position opposite to a sound wave incidence side with respect to said thin films.  
   
   
       25 . The sound-absorbing structure according to  claim 24 , wherein an air layer is formed between said thin films and said rear member.  
   
   
       26 . The sound-absorbing structure according to  claim 24 , wherein a distance between said rear member and said thin films is adjustable.  
   
   
       27 . The sound-absorbing structure according to  claim 21 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films.  
   
   
       28 . The sound-absorbing structure according to  claim 27 , wherein said front member is formed with a large number of fine holes.  
   
   
       29 . The sound-absorbing structure according to  claim 21 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films, a rear member is installed at a position opposite to said front member with respect to said thin films, and a space between said front member and said rear member is divided into plural portions in the surface direction of said thin films.  
   
   
       30 . A sound-absorbing structure including at least one thin film folded so as to have mutually contacting and overlapping portions.  
   
   
       31 . The sound-absorbing structure according to  claim 30 , wherein through holes are formed in said thin film.  
   
   
       32 . The sound-absorbing structure according to  claim 30 , wherein a rear member is installed at a position opposite to a sound wave incidence side with respect to said thin film.  
   
   
       33 . A sound-absorbing structure according to  claim 32 , wherein an air layer is formed between said thin film and said rear member.  
   
   
       34 . The sound-absorbing structure according to  claim 32 , wherein a distance between said rear member and said thin film is adjustable.  
   
   
       35 . The sound-absorbing structure according to  claim 30 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin film.  
   
   
       36 . The sound-absorbing structure according to  claim 35 , wherein said front member is formed with a large number of fine holes.  
   
   
       37 . The sound-absorbing structure according to  claim 30 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin film, a rear member is installed at a position opposite to said front member with respect to said thin film, and a space between said front member and said rear member is divided into plural portions in the surface direction of said thin film.  
   
   
       38 . A sound-absorbing structure including at least a first thin film and a second thin film, said first thin film and said second thin film being layered over each other, and an air-permeable front member being installed at a position on a sound wave incidence side with respect to said thin films.  
   
   
       39 . The sound-absorbing structure according to  claim 38 , wherein said front member is formed with a large number of fine holes.  
   
   
       40 . The sound-absorbing structure according to  claim 38 , wherein a rear member is installed at a position opposite to a sound wave incidence side with respect to said thin films.  
   
   
       41 . The sound-absorbing structure according to  claim 38 , wherein a front member having air permeability is installed at a position on a sound wave incidence side with respect to said thin films, a rear member is installed at a position opposite to said front member with respect to said thin films, and a space between said front member and said rear member is divided into plural portions in the surface direction of said thin films.