Patent ID: 8161745

Claim:
A turbocharger ( 1 ) having a turbine ( 2 ); and having a compressor ( 3 ) which is connected to the turbine ( 2 ) by means of a bearing housing ( 4 ) and which comprises a compressor housing ( 5 ), which compressor housing ( 5 ) has a reference surface (BF) perpendicular to a turbocharger axis (A L ), a valve flange ( 6 ), which is provided with a valve seat ( 11 ), for an overrun air recirculation valve, and also a connecting duct ( 9 ) to a compressor inlet ( 7 ), wherein the valve flange ( 6 ) has a flange surface ( 8 ) which is arranged so as to be inclined by an angle (α) with respect to the reference surface (BF), which angle (α) is defined as follows: α=arctan(( G−F )/( I−V )) where F: spacing from the center of the cross section of the spiral to the turbocharger axis (A L ) and G: the spacing from the central point of the valve opening ( 10 ) to the turbocharger axis A L I: the spacing of the valve flange ( 6 ) between the reference side or the reference surface BF and the central point of the valve opening ( 10 ); V: the spacing from the point of intersection of the valve flange axis A vF with the center of the cross section of the spiral to the reference surface BF, and in that the connecting duct ( 9 ) has a duct axis (A K ) which is arranged so as to be inclined by an angle (β) which is defined as follows: β = arctan ⁡ [ I - ( A 2 · sin ⁢ ⁢ α ) - E G + ( A 2 · cos ⁢ ⁢ α ) - R ] where: A: is the inner diameter of the valve flange ( 6 ), E: is the contour height formed by the spacing from the reference surface BF to the plane of the blade leading edges of the compressor wheel; R: is the spacing from the inner wall of the inlet pipe ( 7 ) to the turbocharger axis A L .