Muffler and catalytic converter devices

Abstract

This invention discloses of a muffler and catalytic converter device, and in addition, a muffler, and a catalytic converter, wherein each type of device uses a porous metal that may function as the sound absorption material for the muffler part of the device, and the substrate for the catalyst coating for the catalytic converter part of the device. In order to be effectiveness as a substrate and to have good sound absorption, the porous metal has a pore density of between 80% and 98% and a pore diameter of between 20 μm and 1200 μm. The porous metal provides structural strength, and is resistant to corrosion, heat, and impact from exhaust flow. It is also easy and cheap to fabricate. For the muffler and catalytic converter device, by combining the customary two devices into one, the cost of production as well as the cost of installation for the device is lowered. Therefore, the muffler and catalytic converter device, muffler, and catalytic converter each having the porous metal that serves functions including good sound absorption characteristics over a wide spectrum of frequencies, that is efficient in the removal of environmental contaminants from the exhaust, and that is durable, and easy and cheap to manufacture for mass production.

We claim:  
     
         1 . A muffler and catalytic converter device receiving exhaust from an engine comprising: 
 an outer shell;    at least one baffle placed inside said shell;    wherein said at least one baffle is made from porous metal having a plurality of pores and having a pore density between 80% and 98%; and    wherein said pores having diameters between 50 μm and 1200 μm.    
     
     
         2 . The muffler and catalytic converter device of  claim 1  wherein the diameters of said pores is between 400 μm and 800 μm and said pore density is between 95% and 98%.  
     
     
         3 . The muffler and catalytic converter device of  claim 1  wherein said porous metal is at least one metal selected from the group consisting of: nickel, iron, and titanium.  
     
     
         4 . The muffler and catalytic converter device of  claim 1  wherein said porous metal is a metal alloy containing at least two components A and B; 
 wherein said A component is between 55 wt % and 95 wt % of said porous metal and is at least one metal selected from the group consisting of: nickel, iron, and titanium; and said B component is between 5 wt. % and 45 wt. % of said porous metal and is at least one element selected from the group consisting of: chromium, aluminum, cobalt, molybdenum, and zinc.  
 
     
     
         5 . The muffler and catalytic converter device of  claim 1  wherein the volume of said muffler and catalytic converter device is 0.3 times to 7 times the displacement of said engine.  
     
     
         6 . The muffler and catalytic converter device of  claim 1 , 
 wherein said baffle has a layer of catalyst coating;    wherein the composition of said catalyst coating comprises of an active ingredient, an assisting ingredient, and a stabilizer;    wherein said active ingredient is at least one rare earth metal selected from the group consisting of: cerium, lanthanum, praseodymium, and neodymium, and at least one precious metal selected from the group consisting of: palladium, platinum, rhodium, and ruthenium;    wherein said assisting ingredient is at least one element selected from the group consisting of: manganese, calcium, barium, magnesium, zinc, and aluminum; and    wherein said stabilizer is at least one element selected from the group consisting of: zirconium, potassium, sodium, and lithium.    
     
     
         7 . The muffler and catalytic converter device of  claim 1  having a plurality of baffles and receiving exhaust from an intake pipe and expelling said exhaust from an outtake pipe; 
 wherein said outer shell has an intake opening and an outtake opening;  
 wherein said intake opening is connected to said intake pipe and said outtake opening is connected to said outtake pipe;  
 wherein said exhaust flows into said shell from said intake pipe and exits said shell from said outtake pipe;  
 wherein the direction of exhaust flow is from said intake opening to said outtake opening;  
 wherein at least one baffle of predetermined thickness is placed across the direction of exhaust flow;  
 wherein at least two of said baffles are separated by a first gap of predetermined thickness; and  
 wherein at least one said baffle is separated from an inner surface of said outer shell by a second gap of predetermined thickness.  
 
     
     
         8 . The muffler and catalytic converter device of  claim 7  having two baffles; 
 wherein the sum of the number of said first gaps and the number of said second gaps is three; and  
 wherein the ratio of the thickness of said three gaps are 1: between 1 and 10: between 1 and 2.  
 
     
     
         9 . The muffler and catalytic converter device of  claim 7  having between 3 and 6 baffles wherein the sum total of the number of said first gaps and the number of said second gaps is between 4 and 7.  
     
     
         10 . The muffler and catalytic converter device of  claim 7  wherein the thickness of said baffles is between 10 mm and 100 mm and the thickness of said first and second gaps is between 10 mm and 150 mm.  
     
     
         11 . The muffler and catalytic converter device of  claim 1  having a plurality of baffles and receiving exhaust from an intake pipe and expelling exhaust from an outtake pipe; 
 wherein said outer shell has an intake opening and an outtake opening;  
 wherein said intake opening is connected to said intake pipe and said outtake opening is connected to said outtake pipe;  
 wherein said exhaust flows into said shell from said intake pipe and exits said shell from said outtake pipe;  
 wherein the direction of exhaust flow is from said intake opening to said outtake opening;  
 wherein at least one baffle of predetermined thickness is placed along the direction of exhaust flow;  
 wherein at least two of said baffles are separated by a first gap of predetermined thickness; and  
 wherein at least one said baffle is separated from a surface of said outer shell by a second gap of predetermined thickness.  
 
     
     
         12 . The muffler and catalytic converter of  claim 11  wherein the thickness of said baffles is between 10 mm and 100 mm and the thickness of said first gaps and said second gaps is between 5 mm and 20 mm.  
     
     
         13 . The muffler and catalytic converter device of  claim 1  wherein at least one said baffle is spiral shaped.  
     
     
         14 . The muffler and catalytic converter of  claim 13  wherein the thickness of said baffles is between 1 mm and 5 mm.  
     
     
         15 . A muffler, comprising: 
 an outer shell;    at least one baffle of sound absorption material is placed inside said shell;    wherein said baffle is made from porous metal having a plurality of pores and having a pore density between 80% and 98%; and    wherein said pores having diameters between 50 μm and 1200 μm.    
     
     
         16 . The muffler of  claim 15  wherein said porous material is at least one metal selected from the group consisting of: nickel, iron, and titanium.  
     
     
         17 . The muffler of  claim 15  wherein said porous metal is a metal alloy containing at least two components A and B; 
 wherein said A component is between 55 wt % to 95 wt % of said porous metal and is at least one metal selected from the group consisting of: nickel, iron, and titanium and said B component is between 5 wt. % to 45 wt. % of said porous metal and is at least one element selected from the group consisting of: chromium, aluminum, cobalt, molybdenum, and zinc.  
 
     
     
         18 . A catalytic converter, comprising: 
 an outer shell;    at least one baffle placed inside said shell;    said baffle is a substrate for at least one layer of catalyst coating;    wherein said baffle is made from porous metal having a plurality of pores and having a pore density between 80% and 98%; and    wherein said pores having diameters between 50 μm and 1200 μm.    
     
     
         19 . The catalytic converter of  claim 18  wherein said porous material is at least one metal selected from the group consisting of: nickel, iron, and titanium.  
     
     
         20 . The catalytic converter of  claim 18  wherein said porous metal is a metal alloy containing at least two components A and B; 
 wherein said A component is between 55 wt % to 95 wt % of said porous metal and is at least one metal selected from the group consisting of: nickel, iron, and titanium and said B component is between 5 wt. % to 45 wt. % of said porous metal and is at least one element selected from the group consisting of: chromium, aluminum, cobalt, molybdenum, zinc, zirconium, vanadium, lanthanum, and neodymium.  
 
     
     
         21 . The catalytic converter of  claim 18 , 
 wherein the composition of said catalyst coating comprises of an active ingredient, an assisting ingredient, and a stabilizer;    wherein said active ingredient is at least one rare earth metal selected from the group consisting of: cerium, lanthanum, praseodymium, and neodymium, and at least one precious metal selected from the group consisting of: palladium, platinum, rhodium, and ruthenium;    wherein said assisting ingredient is at least one element selected from the group consisting of: manganese, calcium, barium, magnesium, zinc, and aluminum; and    wherein said stabilizer is at least one element selected from the group consisting of: zirconium, potassium, sodium, and lithium.