Cooling system for turbocharged internal combustion engine

Abstract

Turbine casing for a turbocharged internal combustion engine for marine applications with an exhaust manifold that is single-piece formed with the turbine casing, and a cooling facility surrounding both the turbine casing as well as the exhaust manifold. The cooling facility is a hollow space, formed by the double wall that can be filled with coolant, whereby the coolant preferably is ocean/lake water. A separate cooling circuit from the cooling facility of the combined turbine casing and exhaust manifold is provided for the cooling of a bearing housing, which is used to support a turbine bearing.

What is claimed is:  
     
         1 . An engine comprising: 
 a turbine casing;    an exhaust manifold coupled to the turbine casing wherein the turbine casing and the exhaust manifold are formed as one piece; and    a cooling structure integrated in the turbine casing and the exhaust manifold wherein the cooling structure allows a coolant to circulate around portions of the turbine casing and the exhaust manifold.    
     
     
         2 . The engine according to  claim 1  wherein he cooling structure comprises: 
 an inner wall;  
 an outer wall spaced from the inner wall to define a cavity there between wherein the coolant circulates in the cavity.  
 
     
     
         3 . The engine according to  claim 2  wherein the outer wall of the cooling structure forms at least a portion of the turbine casing and the exhaust manifold.  
     
     
         4 . The engine according to  claim 1  wherein the cooling structure has an input for each bend of the exhaust manifold.  
     
     
         5 . The engine according to  claim 1  wherein the cooling structure has an outlet positioned near an exhaust gas outlet of the turbine casing.  
     
     
         6 . The engine according to  claim 5  wherein the outlet comprises a plurality of outlets positioned around the exhaust gas outlet.  
     
     
         7 . An engine cooling system comprising 
 a first cooling circuit for cooling an engine block; and    a second cooling circuit for cooling a turbine bearing housing, the second cooling circuit having an input coupled to the first cooing circuit at a first location and an output coupled to the first cooling circuit at a second location.    
     
     
         8 . The system according to  claim 7  wherein the first cooling circuit has a pump and the first location is downstream of the pump and the second location is upstream of the pump.  
     
     
         9 . The engine according to  claim 1  wherein the turbine casing is made of a metal selected from the group consisting of a low-alloy steel, a gray cast iron and aluminum.  
     
     
         10 . An engine comprising: 
 a turbine casing;    an exhaust manifold coupled to the turbine casing wherein the turbine casing and the exhaust manifold are formed as one piece;    a cooling structure integrated in the turbine casing and the exhaust manifold wherein the cooling structure allows a coolant to circulate around portions of the turbine casing and the exhaust manifold; and    an engine cooling system comprising 
 a first cooling circuit for cooling an engine block; and  
 a second cooling circuit for cooling a turbine bearing housing, the second cooling circuit having an input coupled to the first cooing circuit at a first location and an output coupled to the first cooling circuit at a second location.  
   
     
     
         11 . The engine according to  claim 10  wherein he cooling structure comprises: 
 an inner wall;  
 an outer wall spaced from the inner wall to define a cavity there between wherein the coolant circulates in the cavity.  
 
     
     
         12 . The engine according to  claim 11  wherein the outer wall of the cooling structure forms at least a portion of the turbine casing and the exhaust manifold.  
     
     
         13 . The engine according to  claim 10  wherein the cooling structure has an input for each bend of the exhaust manifold.  
     
     
         14 . The engine according to  claim 10  wherein the cooling structure has an outlet positioned near an exhaust gas outlet of the turbine casing.  
     
     
         15 . The engine according to  claim 14  wherein the outlet comprises a plurality of outlets positioned around the exhaust gas outlet.  
     
     
         16 . The system according to  claim 10  wherein the first cooling circuit has a pump and the first location is downstream of the pump and the second location is upstream of the pump.  
     
     
         17 . The engine according to  claim 10  wherein the turbine casing is made of a metal selected from the group consisting of a low-alloy steel, a gray cast iron and aluminum.  
     
     
         18 . A personal watercraft comprising: 
 a hull;    a deck positioned on the hull;    a propulsion device;    an engine for driving the propulsion device; the engine comprising: 
 a turbine casing;  
 an exhaust manifold coupled to the turbine casing wherein the turbine casing and the exhaust manifold are formed as one piece; and  
 a cooling structure integrated in the turbine casing and the exhaust manifold wherein the cooling structure allows a coolant to circulate around portions of the turbine casing and the exhaust manifold.  
   
     
     
         19 . The personal watercraft according to  claim 18  further comprising: 
 a first cooling circuit for cooling an engine block; and  
 a second cooling circuit for cooling a turbine bearing housing, the second cooling circuit having an input coupled to the first cooing circuit at a first location and an output coupled to the first cooling circuit at a second location.  
 
     
     
         20 . The personal watercraft according to  claim 18  wherein the turbine casing is made of a metal selected from the group consisting of a low-alloy steel, a gray cast iron and aluminum.