Device for exhaust-gas routing having a turbocharger

Abstract

A turbocharger assembly for an internal combustion engine, in particular of a commercial vehicle, has a turbocharger with a turbine housing. The turbocharger assembly additionally has an exhaust-gas pipe. The exhaust-gas pipe is arranged downstream of the turbine housing. The exhaust-gas pipe has a diffusor region and an exhaust-gas manifold region.

Claims

1. A turbocharger assembly for an internal combustion engine comprising: a turbocharger with a turbine housing; an exhaust-gas pipe which is arranged downstream of the turbine housing and has a diffusor region defined by an increase in size of the exhaust-gas pipe cross section and an exhaust-gas manifold region; and a wastegate duct which has at least one passage through a pipe wall of the exhaust-gas pipe, wherein the at least one passage is provided downstream of the diffusor region.

2. The turbocharger assembly according to claim 1, wherein the diffusor region extends at least partially into the turbine housing.

3. The turbocharger assembly according to claim 2, wherein the diffusor region extends substantially into the turbine housing.

4. The turbocharger assembly according to claim 1, wherein the exhaust-gas pipe is formed in one piece and/or is a cast part.

5. The turbocharger assembly according to claim 1, wherein the at least one passage is provided upstream of the exhaust-gas manifold region.

6. The turbocharger assembly according to claim 1, wherein the at least one passage is formed such that a flow through the passage is channelled into the exhaust-gas pipe such that the flow from the passage impinges a flow through the exhaust-gas pipe at an angle of less than 90.

7. The turbocharger assembly according to claim 1, wherein the at least one passage is formed such that a flow through the passage is channelled into the exhaust-gas pipe such that the flow from the passage impinges a flow through the exhaust-gas pipe at an angle of less than 45.

8. The turbocharger assembly according to claim 1, wherein the at least one passage is formed such that a flow through the passage is channelled into the exhaust-gas pipe such that the flow from the passage impinges a flow through the exhaust-gas pipe at an angle of less than 25.

9. The turbocharger assembly according to claim 1, wherein a plurality of passages of the wastegate duct through the pipe wall of the exhaust-gas pipe are arranged at equal spaces in a circumferential direction about a longitudinal axis of the exhaust-gas pipe.

10. The turbocharger assembly according to claim 1, wherein an inlet opening of the at least one passage is formed by a metal-cutting process.

11. The turbocharger assembly according to claim 10, wherein the metal-cutting process is a turning process.

12. The turbocharger assembly according to claim 1, wherein an outlet opening of the at least one passage is formed by a casting process.

13. The turbocharger assembly according to claim 1, wherein the diffusor region and the exhaust-gas manifold region at least partially overlap.

14. The turbocharger assembly according to claim 1, wherein the diffusor region extends substantially rectilinearly.

15. The turbocharger assembly according to claim 1, wherein the exhaust-gas pipe further has a flange region for flanging the exhaust-gas pipe onto the turbine housing.

16. The turbocharger assembly according to claim 15, wherein the flange region is arranged downstream of an inlet opening of the exhaust-gas pipe.

17. The turbocharger assembly according to claim 15, wherein the flange region is arranged downstream of the diffusor region.

18. The turbocharger assembly according to claim 15, where the flange region is arranged upstream of the exhaust-gas manifold region.

19. The turbocharger assembly according to claim 15, wherein the at least one passage extends at least partially through the flange region.

20. The turbocharger assembly of claim 1, wherein the internal combustion engine is configured for a commercial vehicle.

21. A motor vehicle comprising: a turbocharger assembly for an internal combustion engine having: a turbocharger with a turbine housing; an exhaust-gas pipe which is arranged downstream of the turbine housing and has a diffusor region defined by an increase in size of the exhaust-gas pipe cross section and an exhaust-gas manifold region; and a wastegate duct which has at least one passage through a pipe wall of the exhaust-gas pipe, wherein the at least one passage is provided downstream of the diffusor region.

22. The motor vehicle of claim 21, wherein the motor vehicle is a commercial vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a plan view of a turbocharger assembly;

(2) FIG. 2 shows a sectional view of an exhaust-gas pipe and of an outlet region of a turbine housing of a turbocharger;

(3) FIG. 3A shows a front view of the exhaust-gas pipe; and

(4) FIG. 3B shows a side view of the exhaust-gas pipe.

DETAILED DESCRIPTION

(5) FIG. 1 shows a device for exhaust-gas routing that is designed as a turbocharger assembly 10. The turbocharger assembly 10 has a turbocharger 11 with a compressor 12 and a turbine 14. The turbocharger assembly 10 further has an exhaust-gas pipe 16.

(6) The compressor 12 is part of an air inlet system of an internal combustion engine (not shown). The compressor 12 comprises a compressor housing 18 and a compressor wheel (not shown) which is rotatably mounted in the compressor housing 18 and intended for compressing the inlet air. The inlet air flows at a compressor inlet opening 18A into the compressor 12 and is compressed therein by the compressor wheel. The compressed inlet air leaves the compressor 12 through a compressor outlet opening 18B. The compressor wheel is driven by a shaft which in turn is driven by a turbine wheel of the turbine 14.

(7) The turbine wheel of the turbine 14 is rotatably mounted in a turbine housing 20. The turbine wheel is driven by hot exhaust gas which expands against the blades of the turbine wheel. The turbine 14 is part of an exhaust-gas system of the internal combustion engine. The turbine 14 is arranged downstream of the combustion chamber(s) of the internal combustion engine. Hot exhaust gases flow into the turbine 14 through a turbine inlet opening 20A and flow through the turbine wheel. After flowing through the turbine wheel, the exhaust gases flow into the exhaust-gas pipe 16.

(8) The exhaust-gas pipe 16 is arranged downstream of the turbine 14 or the turbine housing 20. The exhaust-gas pipe 16 is designed as an exhaust-gas manifold and serves for deflecting the exhaust-gas flow from the turbine 14. The exhaust-gas pipe 16 can have a braking flap (throttle flap).

(9) As is shown in FIG. 2, the exhaust-gas pipe 16 extends partially into the turbine housing 20. Specifically, the exhaust-gas pipe 16 has a diffusor region 22, an exhaust-gas manifold region 24, a flange region 26 and a plurality of passages 28. In the exemplary embodiment shown, the exhaust-gas pipe 16 is formed in one piece as a cast part. The exhaust-gas pipe 16 can also consist of a plurality of pipe segments, for example a diffusor pipe segment and an exhaust-gas manifold pipe segment, which are connected to one another via a flange, for example.

(10) The diffusor region 22 is provided substantially completely in an exhaust-gas-pipe-receiving region 30 of the turbine housing 20. The diffusor region 22 is characterized by a cross-sectional widening along the flow direction. The diffusor region 22 is provided directly downstream of the turbine wheel. In the example shown, the diffusor region 22 extends rectilinearly. In other exemplary embodiments, the diffusor region 22 can be curved and in particular overlap with the exhaust-gas manifold region 24. The diffusor region 22 can also at least partially extend outside the turbine housing 20.

(11) The exhaust-gas manifold region 24 is provided downstream of the diffusor region 22. The exhaust-gas manifold region 24 is characterized by a bending radius by means of which the flow in the exhaust-gas manifold region 24 is deflected. For example, modules for exhaust-gas aftertreatment etc. can be flanged onto an outlet opening 32 of the exhaust-gas manifold region 24 or of the exhaust-gas pipe 16.

(12) The exhaust-gas pipe 16 is connected via the flange region 26 to a flange region 34 of the turbine housing 20. An annular (band) body (not shown) fastens the exhaust-gas pipe 16 to the turbine housing 20 by engaging around both flange regions 26, 34. The flange region 26 of the exhaust-gas pipe 16 is arranged downstream of the diffusor region 22 and upstream of the exhaust-gas manifold region 24. The flange region 26 extends in collar form about an outer circumferential surface of the exhaust-gas pipe 16. Specifically, the flange region 26 has a step-shaped structure. The passages 28 extend through the pipe wall of the exhaust-gas pipe 16 in a radially inner portion of the flange region 26.

(13) The passages 28 extend between an outer circumferential surface of the exhaust-gas pipe 16 and an inner circumferential surface of the exhaust-gas pipe 16. The passages 28 form the outlet region or the outlet nozzles of a wastegate duct 36 (illustrated only partially) of the turbine 14 for bypassing the turbine wheel. The wastegate duct 36 has a wastegate valve (not shown) for metering an exhaust-gas flow through the wastegate duct 36 or through the turbine wheel. Specifically, the wastegate duct 36 has an annular space 38 through which the exhaust gas flows into the inlet openings 40 of the passages 28. The annular space 38 is defined or delimited by an outer circumferential surface of the exhaust-gas pipe 16 about the diffusor region 22 and an inner circumferential surface of the turbine housing 20. The exhaust gas leaves the passages 28 and thus the wastegate duct 36 through the outlet openings 42. The outlet openings 42 are arranged in the rear portion of the diffusor region 22 upstream of the exhaust-gas manifold region 24. The outlet openings 42 can, for example, also be arranged downstream of the diffusor region 22 and in the exhaust-gas manifold region 24. In the embodiment shown, the longitudinal axes of the passages 28 each form an acute angle, i.e. an angle of less than 90, with a longitudinal axis of the diffusor region 16. Preference is given in particular to small inflow angles, for example of less than 45 or 25. Exhaust gas entering through the passages 28 thus brings about comparatively little swirling when flowing into the exhaust-gas pipe 16.

(14) As can be gathered from FIGS. 3A and 3B, a total of six passages 28 are provided in the exemplary embodiment shown. The six passages 28 are arranged symmetrically in a circumferential direction about the longitudinal axis of the diffusor region 22. In other embodiments, the exhaust-gas pipe 16 can have more or fewer passages 28 in symmetrical or asymmetrical arrangements. The inlet openings 40 are positioned in an annular surface 44 which lies in a plane perpendicular to the longitudinal axis of the diffusor region 22. The inlet openings 40 are first produced by transverse turning of the annular surface 44. In other words, the passages 28 are not yet completely formed during primary forming, i.e. casting. After primary forming, the passages 28 are blind holes which extend from the outlet openings 42 into the pipe wall of the exhaust-gas pipe 16. As a result of a metal-cutting process, here transverse forming, the passages 28 are opened when forming the annular surface 44, i.e. the inlet openings 40 are created only after primary forming.

(15) The present disclosure is not restricted to the above-described exemplary embodiments. Rather, a plurality of variants and modifications are possible which also make use of the concept of the present disclosure and therefore fall within the scope of protection. In particular, the present disclosure also claims protection for the subject matter and the features of the dependent claims independently of the claims referred back to.

LIST OF REFERENCE SIGNS

(16) 10 Turbocharger assembly 12 Compressor 14 Turbine 16 Exhaust-gas pipe 18 Compressor housing 18A Compressor inlet opening 18B Compressor outlet opening 20 Turbine housing 20A Turbine inlet opening 22 Diffusor region 24 Exhaust-gas manifold region 26 Flange region of the exhaust-gas pipe 28 Passage 30 Exhaust-gas-pipe-receiving region 32 Outlet opening of the exhaust-gas pipe 34 Flange region of the turbine housing 36 Wastegate duct 38 Annular space 40 Inlet opening of the passage 42 Outlet opening of the passage 44 Annular surface