Multi-segment turbocharger bearing housing and methods therefor

Abstract

A turbocharger ( 102, 202, 302 ) including a rotating assembly ( 114, 214, 314 ) having a compressor wheel ( 120, 220, 320 ) and a turbine wheel ( 110, 210, 310 ) mounted on opposite ends of a shaft ( 112, 212, 312 ). A bearing housing ( 160, 260, 360 ) supports the rotating assembly ( 114, 214, 314 ) and comprises at least two segments ( 189, 190; 289, 290; 389, 390 ). Each segment ( 189, 190; 289, 290; 389, 390 ) has an opening large enough to radially receive the rotating assembly ( 114, 214, 314 ). The bearing housing segments ( 189, 190; 289, 290; 389, 390 ) are fastened ( 193 ) together and a flexible seal may be provided between the segments. The bearing housing ( 160, 260, 360 ) may house rolling element bearings ( 325 ) or journal bearings ( 149 ), for example. The bearing housing ( 160, 260, 360 ) is split axially ( 101, 201, 301 ) into an upper segment ( 189, 289, 389 ) and a lower segment ( 190, 290, 390 ). Alternatively, the bearing housing ( 160, 260, 360 ) is split axially ( 101, 201, 301 ) into a left segment and a right segment. The turbocharger ( 102 ) may further comprise an electric motor stator ( 148 ) disposed in the bearing housing ( 160 ). The bearing housing ( 160 ) may also include a defined passageway ( 143 ) extending around the stator ( 148 ) and configured to receive a cooling liquid.

1 . A turbocharger ( 102 ,  202 ,  302 ), comprising:
 a rotating assembly ( 114 ,  214 ,  314 ) including a compressor wheel ( 120 ,  220 ,  320 ) and a turbine wheel ( 110 ,  210 ,  310 ) disposed on opposite ends of a shaft ( 112 ,  212 ,  312 ); and   a bearing housing ( 160 ,  260 ,  360 ) configured to support the rotating assembly ( 114 ,  214 ,  314 ) comprising at least two segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ), wherein each segment has an opening ( 175 ) sized to receive the rotating assembly ( 114 ,  214 ,  314 ).   
     
     
         2 . The turbocharger ( 102 ,  202 ,  302 ) of  claim 1 , wherein the bearing housing ( 160 ,  260 ,  360 ) is split axially ( 101 ,  201 ,  301 ) into an upper segment ( 189 ,  289 ,  389 ) and a lower segment ( 190 ,  290 ,  390 ). 
     
     
         3 . The turbocharger ( 102 ,  202 ,  302 ) of  claim 1 , wherein the bearing housing ( 160 ,  260 ,  360 ) is split axially ( 101 ,  201 ,  301 ) into a left segment and a right segment. 
     
     
         4 . The turbocharger ( 102 ) of  claim 1 , further comprising an electric motor stator ( 148 ) disposed in the bearing housing ( 160 ). 
     
     
         5 . The turbocharger ( 102 ) of  claim 4 , wherein the bearing housing ( 160 ) includes a defined passageway ( 143 ) extending around the stator ( 148 ) and configured to receive a liquid. 
     
     
         6 . The turbocharger ( 102 ,  202 ,  302 ) of  claim 1 , wherein the bearing housing segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ) are coupled by fasteners ( 193 ), and wherein a flexible seal is provided between the segments. 
     
     
         7 . The turbocharger ( 302 ) of  claim 1 , wherein the bearing housing ( 360 ) houses rolling element bearings ( 325 ). 
     
     
         8 . A turbocharger ( 102 ), comprising:
 a rotating assembly ( 114 ) including a rotor ( 147 ) mounted on a shaft ( 112 ) and a compressor wheel ( 120 ) and a turbine wheel ( 110 ) disposed on opposite ends of the shaft ( 112 );   a bearing housing ( 160 ) configured to support the rotating assembly ( 114 ) and comprising upper ( 189 ) and lower ( 190 ) segments, wherein each segment has an opening ( 175 ) sized to receive the rotating assembly ( 114 ); and   a stator ( 148 ) disposed in the bearing housing ( 160 ) and around the rotor ( 147 ).   
     
     
         9 . The turbocharger ( 102 ) of  claim 8 , wherein the bearing housing ( 160 ) includes a defined passageway ( 143 ) around the stator ( 148 ) adapted for receiving a cooling liquid. 
     
     
         10 . The turbocharger ( 102 ) of  claim 9 , wherein the bearing housing segments ( 189 ,  190 ) are coupled by fasteners ( 193 ), and wherein a flexible seal is provided in a groove ( 198 ) between the segments. 
     
     
         11 . A method for enclosing a rotating assembly ( 114 ,  214 ,  314 ) of a turbocharger ( 102 ,  202 ,  302 ), the method comprising:
 providing at least two bearing housing segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ) which together form a bearing housing ( 160 ,  260 ,  360 ) including a bearing bore ( 177 ,  178 ) and an insert bore ( 179 );   machining complementary mating faces ( 196 ,  197 ) of the segments;   machining features ( 193 ) as required for alignment and fastening of the segments to each other;   machining the bearing bore ( 177 ,  178 ) and the insert bore ( 179 );   machining oil feed passages ( 181 - 183 ) and oil drain features ( 145 ,  187 ) into at least one segment, wherein at least one oil feed bore ( 181 ,  182 ) is drilled from the radially inner surface of the corresponding bearing housing segment;   balancing a rotating assembly ( 114 ,  214 ,  314 );   installing the rotating assembly ( 114 ,  214 ,  314 ) into at least one of the bearing housing segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ); and   joining the segments together to enclose the rotating assembly ( 114 ,  214 ,  314 ).   
     
     
         12 . The method of  claim 11 , wherein the rotating assembly ( 114 ) includes a rotor ( 147 ) of an electric motor, and wherein a corresponding stator ( 148 ) is housed in the bearing housing ( 160 ). 
     
     
         13 . The method of  claim 11 , wherein the at least two bearing housing segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ) are provided by separately casting each segment. 
     
     
         14 . The method of  claim 11 , wherein the at least two bearing housing segments are provided by casting a unitary bearing housing and subsequently cutting the unitary bearing housing into the at least two bearing housing segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ). 
     
     
         15 . The method of  claim 11 , wherein the segments ( 189 ,  190 ;  289 ,  290 ;  389 ,  390 ) are assembled to each other before the step of machining the bearing bore ( 177 ,  178 ) and the insert bore ( 179 ).