Acoustic dumper for exhaust system

Abstract

An exhaust system has a tubular member ( 1 ) to discharge exhaust produced in an engine or a compressor and a muffler ( 5 ) connected to the tubular member ( 1 ). An exhaust chamber 10 to attenuate noise emitted from the muffler ( 5 ) due to pulsation of the exhaust is arranged in the tubular member ( 1 ) or at an exhaust upstream side in the muffler ( 5 ).

What is claimed is:  
     
         1 . An acoustic damper for exhaust system comprising; 
 a tubular member configured to discharge exhaust from a machine having one of an engine or a compressor and attenuate acoustic energy of a first frequency band; and    a resonator set configured to attenuate acoustic energy of a second frequency band, which is different from the first frequency band and modulates the first frequency band.    
     
     
         2 . The acoustic damper for exhaust system of  claim 1 , wherein: 
 the resonator set comprises at least two resonators;    each of the resonators has a fast end opening to an inner face of the tubular member and a closed second end; and    the resonators have different lengths.    
     
     
         3 . The acoustic damper for exhaust system of  claim 1 , wherein: 
 the resonator set comprises at least one resonator; and    the resonator has a first end opening to an inner face of the tubular member and a closed second end including a plane that is not in parallel with the virtual plane of the first end.    
     
     
         4 . The acoustic damper for exhaust system of  claim 1 , wherein: 
 the resonator set comprises at least one resonator; and    each end of the resonator is open to an inner face of the tubular member.    
     
     
         5 . The acoustic damper for exhaust system of  claim 2 , wherein each of the resonators comprises noise absorbing material and a scatter preventive part.  
     
     
         6 . The acoustic damper for exhaust system of  claim 3 , wherein each of the resonators comprises noise absorbing material and a scatter preventive part.  
     
     
         7 . The acoustic damper for exhaust system of  claim 4 , wherein each of the resonators comprises noise absorbing material and a scatter preventive part.  
     
     
         8 . The acoustic damper for exhaust system of  claim 1 , wherein the resonator set is arranged at an exhaust upstream side in a muffler connected to an end of the tubular member.  
     
     
         9 . The acoustic damper for exhaust system of  claim 2 , wherein the resonator set is arranged at an exhaust upstream side in a muffler connected to an end of the tubular member.  
     
     
         10 . The acoustic damper for exhaust system of  claim 3 , within the resonator set is arranged at exhaust upstream side in a muffler connected to an end of the tubular member.  
     
     
         11 . The acoustic damper for exhaust system of  claim 9 , wherein the resonator set is formed on a front end plate of the muffler.  
     
     
         12 . The acoustic damper for exhaust system of  claim 10 , wherein the resonator set is formed on a front end plate of the muffler.  
     
     
         13 . The acoustic damper for exhaust system of  claim 4 , wherein the resonator set is arranged at an exhaust upstream side in a muffler connected to an end of the tubular member.  
     
     
         14 . The acoustic damper for exhaust system of  claim 9 , wherein each of the resonators comprises noise absorbing material and a scatter preventive part.  
     
     
         15 . The acoustic damper for exhaust sytem of  claim 10 , wherein each of the resonators comprises noise absorbing, material and a scatter preventive part.  
     
     
         16 . The acoustic damper for exhaust system of  claim 13 , wherein each of the resonators comprises noise absorbing material and a scatter preventive part.