Impeller and turbocharger

Abstract

An impeller having a rotation axis, a radial direction, a backplate and a number of vanes which are connected to the backplate at a line of connection is provided. Each vane has an upstream side, a downstream side and an outer side. The downstream side of each vane has an edge portion which is located near the outer side. The vanes project radially over the backplate and the downstream side further includes a connecting portion connecting the edge portion to the backplate and including an angle with the radial direction. The connecting portion includes a convex rounded portion which is located near the line of connection. Moreover, a turbocharger having an inventive impeller is disclosed.

1 . An impeller comprising a rotation axis, a radial direction, a backplate and a number of vanes which are connected to the backplate at a line of connection, each vane comprising an upstream side, a downstream side and an outer side, the downstream side of each vane comprising an edge portion which is located near the outer side,
 wherein the vanes project radially over the backplate and the downstream side further comprises a connecting portion connecting the edge portion to the line of connection, the connecting portion comprising a convex rounded portion which is located near the line of connection, characterized in that an angle between the radial direction and a tangent of the connecting portion adjacent to the line of connection has a value of between 15° and 25°.   
     
     
         2 . The impeller as claimed in  claim 1 , characterised in that the edge portion is orientated perpendicular to the radial direction. 
     
     
         3 . The impeller as claimed in  claim 1 , characterised in that each vane is backswept on moving in an airflow direction from its upstream side to its downstream side. 
     
     
         4 . The impeller as claimed in  claim 1 , characterised in that the backplate comprises a radially outer peripheral surface and the connecting portion is adjacent to the radially outer peripheral surface of the backplate. 
     
     
         5 . The impeller as claimed in  claim 4 , characterised in that the radially outer peripheral surface of the backplate is located in a plane with a normal being locally parallel to the radial direction. 
     
     
         6 . The impeller as claimed in  claim 4 , characterised in that the radially outer peripheral surface of the backplate is located in a plane with a normal which includes an angle between 0° and 45° with the radial direction. 
     
     
         7 . The impeller as claimed in  claim 6 , characterised in that the angle has a value between 15° and 25°. 
     
     
         8 . (canceled) 
     
     
         9 . (canceled) 
     
     
         8 . The impeller as claimed in  claim 1 , characterised in that the edge portion of the downstream side has a length in the direction of the rotation axis of more than 50% of the length of the downstream side in the direction of the rotation axis. 
     
     
         9 . A compressor comprising an impeller as claimed in  claim 1 . 
     
     
         10 . A turbocharger comprising a compressor as claimed in  claim 9 .