Exhaust flow insulator for an exhaust system device

Abstract

An exhaust system device comprising a liquid-cooled non-ferrous housing including a liquid cooling passage and defining a path for exhaust gas, and an exhaust flow insulator carried in the exhaust gas path of the housing to convey exhaust gas through the housing to limit heat transfer from exhaust gas to the housing.

1 . An exhaust system device comprising:
 a liquid-cooled non-ferrous housing including an inlet, an outlet, a path for exhaust gas between the inlet and the outlet, and a liquid cooling passage adjacent the exhaust gas path; and   a exhaust flow insulator carried in the exhaust gas path of the housing to convey exhaust gas through the housing to limit heat transfer from exhaust gas to the housing, wherein said insulator is composed of at least one of a ferrous material or a ceramic material.   
     
     
         2 . An exhaust system device as set forth in  claim 1  wherein the housing includes at least one of an exhaust manifold housing or a turbocharger turbine housing, and the insulator is carried in the exhaust gas path of the housing substantially from the inlet and substantially to the outlet. 
     
     
         3 . An exhaust system device as set forth in  claim 1 , wherein at least a portion of the insulator is in direct contact with the housing. 
     
     
         4 . An exhaust system device as set forth in  claim 3 , wherein at least a portion of the insulator is a ceramic coating. 
     
     
         5 . An exhaust system device as set forth in  claim 1  wherein the insulator is comprised of multiple portions. 
     
     
         6 . An exhaust system device as set forth in  claim 5  wherein the multiple portions include flanges coupled to one another along a seam. 
     
     
         7 . An exhaust system device as set forth in  claim 1  wherein the housing is cast from aluminum and the insulator is manufactured from steel. 
     
     
         8 . An exhaust system device as set forth in  claim 1  wherein the housing is cast around the insulator. 
     
     
         9 . An exhaust system device as set forth in  claim 1  wherein the housing is comprised of multiple portions coupled together. 
     
     
         10 . An exhaust system device as set forth in  claim 9  wherein the housing is of a clamshell configuration having one housing portion coupled to another housing portion. 
     
     
         11 . An exhaust system device as set forth in  claim 1 , further comprising an insulating void between the insulator and the housing. 
     
     
         12 . An exhaust system device as set forth in  claim 11  wherein the insulator includes apertures to communicate exhaust gas from the interior of the insulator to the insulating void between the insulator and the housing. 
     
     
         13 . An exhaust system device as set forth in  claim 11  wherein the insulating void is vacuum vented by a vacuum vent passage in the housing in fluid communication at one end with the insulating void and communicable at another end with a vacuum vent passage in an engine. 
     
     
         14 . An exhaust system device as set forth in  claim 11 , further comprising an insulation material disposed in the insulating void between the insulator and the housing. 
     
     
         15 . An exhaust system device as set forth in  claim 1 , wherein the insulation material is at least one of cast in place, poured into the insulating void, assembled between portions of the housing, or blown into the insulating void, and includes at least one of fiber insulation, aluminum insulation, ceramic ball insulation, or aerogel insulation.