Ebullient cooled turbocharger bearing housing

Abstract

A turbocharged internal combustion engine system including a liquid-cooled internal combustion engine, a heat exchanger for cooling the liquid, a pump for pumping cooled liquid from the heat exchanger to the engine, and a turbocharger including a rotary turbine and a rotary compressor, a housing containing the turbine and the compressor, a shaft interconnecting the turbine and the compressor and bearings journalling the shaft within the housing between the turbine and compressor. Exhaust gases from the engine are directed through the turbine to drive the same and air from the compressor is directed to the engine. A liquid passage is located in the turbocharger housing and is operatively interposed between the turbine and the bearing. The passage has a lower inlet and an upper outlet and liquid coolant from the engine is directed to the inlet. Coolant from the output is directed to the heat exchanger or other suitable compartment in the engine coolant system so as to allow flow while the engine is operating and under the following conditions. Thermosiphoning of the coolant will occur through the passage when the engine is not operative, resulting in ebullient cooling of the housing immediately adjacent the bearings when the engine is not operating. As a result, thermal damage to the bearings is prevented and coking of the residual oil on the inside walls of the housing is also prevented.

What is claimed is: 
     
       1. In a turbocharged, internal combustion engine system, the combination of: a liquid cooled, internal combustion engine;   a heat exchanger for cooling the liquid from the engine;   a turbocharger including a rotary turbine and a rotary compressor, housings containing the turbine and the compressor, a shaft interconnecting the turbine and the compressor and bearings journalling the shaft within the housing adjacent the turbine;   means for directing exhaust gases from said engine to said turbine to drive the same;   means for directing air from said compressor to the engine;   a liquid passage in said housing operatively interposed between said turbine and said bearings and having a lower inlet and an upper outlet;   means for directing liquid coolant from said engine to said inlet; and   means for directing coolant from said outlet to said heat exchanger whereby thermosiphoning of said coolant through said passage will occur when said engine is not operative and ebullient cooling of said housing immediately adjacent said bearings will occur .Iadd.due .Iaddend.to the presence of liquid in said passage to thereby prevent excessive heat buildup in said housing even when said engine is not operative and thereby prevent thermal damage to said bearings.   
     
     
       2. The system of claim 1 further including an oil inlet and an oil outlet in said housing and including an oil passage extending to said bearings, liquid coolant in said passage cooling said bearings to prevent the coking of the oil therein even when said engine is nonoperative. 
     
     
       3. The system of claim 2 wherein said heat exchanger includes a pressure seal and is operative to contain fluid under elevated pressure during operation of said engine. 
     
     
       4. The system of claim 1 wherein said liquid passage comprises an at least partially annular chamber disposed about said shaft. .[.5. A turbocharger for use with a liquid cooled, internal combustion engine comprising: a housing including turbine and compressor chambers;   a shaft in said housing extending between and into said chambers;   bearings in said housing adjacent said chambers and journalling said shaft;   an impeller mounted on said shaft within said compressor chamber;   a turbine wheel mounted on said shaft within said chamber;   an air inlet and an air outlet in said compressor chamber;   an engine exhaust inlet and an engine exhaust outlet in said turbine chamber;   an annular or partly annular liquid coolant receiving chamber in said housing about said shaft and between and sealed from said turbine chamber and said adjacent bearings;   an upper liquid engine coolant outlet for said annular or partly annular chamber;   a lower liquid engine coolant inlet for said chamber; and   lubricant passages separate from said chamber and coolant inlet and outlet   
     
     
        and extending to said bearings..]. .[.6.  A turbocharger for use with a liquid cooled, internal combustion engine comprising: a housing including turbine and compressor chambers;   a shaft in said housing extending between and into said chambers;   bearings in said housing adjacent said chambers and journalling said shaft;   an impeller mounted on said shaft within said compressor chamber;   a turbine wheel mounted on said shaft within said turbine chamber;   an air inlet and an air outlet in said compressor chamber;   an engine exhaust inlet and an engine exhaust outlet in said turbine chamber;   an engine coolant receiving passage in said housing between said turbine chamber and said adjacent bearings and in heat transfer relation to but sealed from said turbine chamber;   at least one lower, liquid engine coolant inlet in said housing for said passage;   at least one upper, liquid engine coolant outlet for said passage;   lubricant passages in said housing extending to said bearings, said lubricant passages being separate from said coolant passage; and   at least one inlet and outlet in said housing for said lubricant passages..].