Exhaust gas turbocharger for an internal combustion engine
An exhaust gas turbocharger for an internal combustion engine has an exhaust gas turbine in the exhaust gas train and a compressor in the intake tract, whereby an adjustable throttle device is provided upstream from the compressor wheel, for regulating the air mass stream to be supplied. The throttle device comprises a first guide grid and a second guide grid in the inflow region to the compressor wheel. Each guide grid possesses an adjustable grid geometry.
1. An exhaust gas turbocharger for an internal combustion engine, having an exhaust gas turbine in the exhaust gas train and a compressor in the intake tract, whereby a compressor wheel is disposed in a compressor wheel inflow channel, which wheel is driven by a turbine wheel of the exhaust gas turbine, having an adjustable throttle device upstream from the compressor wheel, for regulating the air mass stream to be supplied, wherein the throttle device comprises a first guide grid and a second guide grid in the inflow region to the compressor wheel, whereby each guide grid has an adjustable grid geometry.
2. The exhaust gas turbocharger as claimed in claim 1 , wherein the two guide grids are spaced axially apart.
3. The exhaust gas turbocharger as claimed in claim 1 , wherein the grid geometries comprise one guide grid ring, in each instance, having guide vanes and an accommodation matrix for accommodating the guide grid rings.
4. The exhaust gas turbocharger as claimed in claim 1 , wherein the setting movements of the grid geometries of the two guide grids are coupled by way of a common activation organ.
5. The exhaust gas turbocharger as claimed in claim 4 , wherein the common activation organ comprises an axially adjustable sliding sleeve.
6. The exhaust gas turbocharger as claimed in claim 3 , wherein the sliding sleeve has an accommodation matrix in the region of a first axial face, and a guide grid ring in the region of the opposite axial face.
7. The exhaust gas turbocharger as claimed in claim 1 , wherein each grid geometry has an activation organ assigned to it, in each instance.
8. The exhaust gas turbocharger as claimed in claim 7 , wherein the two activation organs are configured as a sliding sleeve, in each instance.
9. The exhaust gas turbocharger as claimed in claim 7 , wherein an activation organ forms a spin surface for the air mass stream that flows through, in the opened position of a guide grid.
10. The exhaust gas turbocharger as claimed in claim 1 , wherein an air collection chamber that communicates with the compressor wheel inflow channel lies ahead of the compressor wheel, whereby at least one guide grid is disposed in the transition from the air collection chamber to the compressor wheel inflow channel.
11. The exhaust gas turbocharger as claimed in claim 10 , wherein the air collection chamber surrounds the compressor wheel inflow channel radially, at least in part.
12. The exhaust gas turbocharger as claimed in claim 1 , wherein a guide grid has at least two segments having different grid geometries over its axial expanse.
13. The exhaust gas turbocharger as claimed in claim 12 , wherein the segments each have a different number of guide grid vanes.
14. The exhaust gas turbocharger as claimed in claim 12 , wherein the guide vanes of the guide grid continuously undergo a shortening of the chord length with an increasing vane height, proceeding from a bottom vane height.