EXHAUST SYSTEM AS WELL AS MOTOR VEHICLE WITH AN EXHAUST SYSTEM

Abstract

An exhaust system for an internal combustion engine of a motor vehicle includes a single exhaust-gas inlet line, two exhaust-gas outlet lines connected in an exhaust gas-conducting manner to the exhaust-gas inlet line, and an active silencing device. The active silencing device is connected in a sound-conducting manner to the two exhaust-gas outlet lines. Furthermore, a motor vehicle with such an exhaust system is provided.

Claims

1. An exhaust system for an internal combustion engine of a motor vehicle comprising: a single exhaust-gas inlet line; two exhaust-gas outlet lines connected in an exhaust gas-conducting manner to the single exhaust-gas inlet line; and an active silencing device, which is connected in a sound-conducting manner to the two exhaust-gas outlet lines.

2. The exhaust system according to claim 1, wherein the single exhaust-gas inlet line is connected in an exhaust gas-conducting manner to the two exhaust-gas outlet lines via a passive silencer.

3. The exhaust system according to claim 2, wherein sections of the single exhaust-gas inlet line and/or of at least one of the two exhaust-gas outlet lines, run inside a silencer housing of the passive silencer.

4. The exhaust system according to claim 1, wherein the two exhaust-gas outlet lines form a T connection or a Y connection with the single exhaust-gas inlet line or an intermediate exhaust-gas line, wherein the intermediate exhaust-gas line is connected in an exhaust gas-conducting manner to both of the two exhaust-gas outlet lines and to the single exhaust-gas inlet line.

5. The exhaust system according to claim 1, wherein the two exhaust-gas outlet lines are formed by opposite sections of a common exhaust-gas outlet pipe.

6. The exhaust system according to claim 1, wherein the active silencing device is connected in a sound-conducting manner to the two exhaust-gas outlet lines via a sound coupling-in line, wherein the sound coupling-in line surrounds exhaust-gas inlet-facing ends of the two exhaust-gas outlet lines on an outside and runs substantially concentric to the exhaust-gas inlet-facing ends of the two exhaust-gas outlet lines.

7. The exhaust system according to claim 6, wherein the single exhaust-gas inlet line is connected in an exhaust gas-conducting manner to the two exhaust-gas outlet lines via a passive silencer, and wherein the sound coupling-in line runs at least partly inside a silencer housing of the passive silencer.

8. The exhaust system according to claim 6, wherein the single exhaust gas inlet line passes through a wall of the sound coupling-in line, or wherein an intermediate exhaust-gas line is connected in an exhaust gas-conducting manner to both of the two exhaust-gas outlet lines and to the single exhaust-gas inlet line, and wherein the intermediate exhaust-gas line passes through a wall of the sound coupling-in line.

9. The exhaust system according to claim 6, wherein at least one of the two exhaust-gas outlet lines, comprises a perforated section in an area surrounded by the sound coupling-in line.

10. The exhaust system according to claim 9, wherein both of the two exhaust-gas outlet lines comprise perforated sections and the perforated sections are arranged on opposite sides of the single exhaust-gas inlet line, or wherein an intermediate exhaust-gas line is connected in an exhaust gas-conducting manner to both of the two exhaust-gas outlet lines and to the single exhaust-gas inlet line, and wherein both of the two exhaust-gas outlet lines comprise perforated sections and the perforated sections are arranged on opposite sides of the intermediate exhaust-gas line.

11. The exhaust system according to claim 6, wherein the active silencing device is connected in a sound-conducting manner to the sound coupling-in line via a sound line.

12. The exhaust system according to claim 11, wherein the single exhaust-gas inlet line is connected in an exhaust gas-conducting manner to the two exhaust-gas outlet lines via a passive silencer, and wherein the sound line runs outside a silencer housing of the passive silencer.

13. The exhaust system according to claim 1, wherein the two exhaust-gas outlet lines are exhaust tail pipes.

14. The exhaust system according to claim 1, wherein the singe exhaust-gas inlet line has a substantially oval cross section at an exhaust-gas outlet-facing end.

15. A motor vehicle including the exhaust system according to claim 1.

16. The exhaust system according to claim 2, wherein sections of the single exhaust-gas inlet line, and/or both of the two exhaust-gas outlet lines, run inside a silencer housing of the passive silencer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Various embodiment examples are shown in the attached drawings.

[0032] FIG. 1 schematically shows a motor vehicle with an exhaust system according to a first embodiment,

[0033] FIG. 2 shows the exhaust system of FIG. 1,

[0034] FIG. 3 shows a section of the exhaust system from FIG. 2, wherein a portion is represented transparently,

[0035] FIG. 4 schematically shows a detail of the exhaust system according to FIGS. 1 to 3, and

[0036] FIG. 5 schematically shows an exhaust system according to a second embodiment.

DETAILED DESCRIPTION

[0037] FIG. 1 shows a motor vehicle 10 with an exhaust system 12 according to a first embodiment, which is coupled to an internal combustion engine 14 which has three cylinders arranged in a row.

[0038] As can also be seen in particular in FIG. 2, the exhaust system 12 comprises a single exhaust-gas inlet line 16 and two exhaust-gas outlet lines 18 connected in an exhaust gas-conducting manner thereto, which are exhaust tail pipes in the embodiment represented.

[0039] In addition, the exhaust system 12 has an active silencing device 20 which is connected in a sound-conducting manner to the two exhaust-gas outlet lines 18.

[0040] An active silencing device known from the state of the art, which comprises a loudspeaker with which it can generate sound which is out of phase with the sound carried by the exhaust gas flow, is used as active silencing device 20.

[0041] For this purpose, the active silencing device 20 is coupled to the exhaust-gas outlet lines 18 via a sound line 22 and a sound coupling-in line 24.

[0042] In other words, the active silencing device 20 is connected in a sound-conducting manner to the sound coupling-in line 24 via the sound line 22.

[0043] The sound coupling-in line 24 in turn is connected in a sound-conducting manner to the exhaust-gas outlet lines 18.

[0044] The exhaust system 12 further has a passive silencer 26 with a silencer housing 28.

[0045] In the first embodiment, the exhaust-gas inlet line 16 is connected in an exhaust gas-conducting manner to the exhaust-gas outlet lines 18 via the passive silencer 26.

[0046] In FIG. 3, an upper side of the silencer housing 28 is represented transparent with the result that the interior thereof can be seen.

[0047] Here, sections of the exhaust-gas inlet line 16 and of both exhaust-gas outlet lines 18 run inside the silencer housing 28.

[0048] More precisely, a section of the exhaust-gas inlet line 16 facing away from the internal combustion engine 14, thus the exhaust-gas outlet-facing end thereof, runs inside the silencer housing 28.

[0049] The exhaust-gas outlet-facing end can have a substantially oval cross section.

[0050] In this context, the cross section is usually chosen such that both a good muffling performance of the passive silencer 26 and a compact construction of the exhaust system 12 as a whole are achieved.

[0051] With regard to the exhaust-gas outlet lines 18, the sections facing the internal combustion engine 14 or the exhaust-gas inlet line 16 respectively thus run inside the silencer housing 28.

[0052] In addition, the two exhaust-gas outlet lines 18 form a T connection 32 with an intermediate exhaust-gas line 30. Both exhaust-gas outlet lines 18 are thus connected in an exhaust gas-conducting manner to the intermediate exhaust-gas line 30.

[0053] The T connection 32 lies completely inside the silencer housing 28.

[0054] In addition, the intermediate exhaust-gas line 30 is connected in an exhaust gas-conducting manner to the exhaust-gas inlet line 16 via the internal volume of the passive silencer 26.

[0055] In the first embodiment, the two exhaust-gas outlet lines 18 are formed by opposite sections of a common exhaust-gas outlet pipe 34.

[0056] As already mentioned, the active silencing device 20 is connected in a sound-conducting manner to the exhaust-gas outlet lines 18 via the sound coupling-in line 24, in the present case therefore also to the exhaust-gas outlet pipe 34.

[0057] Here, the sound coupling-in line 24 has a larger diameter than the exhaust-gas outlet lines 18 and surrounds the exhaust-gas inlet-facing ends of the exhaust-gas outlet lines 18 on the outside (see FIG. 4 in particular). In the present case, the sound coupling-in line 24 therefore also surrounds the exhaust-gas outlet pipe 34.

[0058] At the same time, the sound coupling-in line 24 runs substantially concentric to the exhaust-gas outlet lines 18 which are of course formed by a common exhaust-gas outlet pipe 34.

[0059] The sound coupling-in line 24 runs partly inside the silencer housing 28 and partly outside it (cf. FIG. 4).

[0060] In order to enable an interaction between the out-of-phase sound generated by the active silencing unit 20 and the exhaust gas flow routed in the exhaust-gas outlet lines 18, both exhaust-gas outlet lines 18 have a perforated section 36.

[0061] In order to illustrate that the two perforated sections 36 can be designed the same but do not have to be, they differ in FIG. 4 with respect to the number of openings belonging to the perforated section 36 as well as the arrangement of the openings.

[0062] The perforated sections 36 are arranged in that area of the exhaust-gas outlet lines 18 which is surrounded by the sound coupling-in line 24.

[0063] Furthermore, the perforated sections 36 are placed on opposite sides of the intermediate exhaust-gas line 30.

[0064] The intermediate exhaust-gas line 30 passes through a wall of the sound coupling-in line 24. The T connection 32 thus lies inside the sound coupling-in line 24.

[0065] The sound line 22 runs completely outside the silencer housing 28.

[0066] In summary, exhaust gas emerging from the internal combustion engine 14 therefore flows via the exhaust-gas inlet line 16 into the silencer housing 28 of the passive silencer 26. From there, it passes via the intermediate exhaust-gas line 30, which is coupled to the two exhaust-gas outlet lines 18 via the T connection 32, into the two exhaust-gas outlet lines 18. These conduct the exhaust gas to the surroundings.

[0067] Within the meaning of muffling the sound carried by the exhaust gas, out-of-phase sound, which is often also referred to as anti-noise, is generated in the active silencing device 20. From there, the out-of-phase sound is routed into the sound coupling-in line 24 via the sound line 22. It thus passes into an annular space, which is formed by the sound coupling-in line 24 and the respectively exhaust-gas inlet-facing ends of the exhaust-gas outlet lines 18. From this, the sound can escape via the openings of the perforated sections 36 into the interior of the exhaust-gas outlet lines 18, where it interacts with the sound carried by the exhaust gas in order to muffle it.

[0068] In contrast to the first embodiment, the second embodiment of the exhaust system 12 shown in FIG. 5 dispenses with the passive silencer 26.

[0069] This variant can be chosen when the exhaust system 12 is to be designed in a particularly space-saving manner.

[0070] This variant can also be used when the active silencing device 20 is designed in such a way that it can ensure sufficient muffling of the sound carried by the exhaust gas without the aid of a passive silencer.

[0071] In addition, in the second embodiment no intermediate exhaust-gas line 30 is used with the result that the exhaust-gas inlet line 16 forms the T connection 32 with the exhaust-gas outlet lines 18. The exhaust gas therefore flows directly from the exhaust-gas inlet line 16 into the exhaust-gas outlet lines 18.

[0072] The path of the out-of-phase sound generated by the active silencing device 20 and its superposition with the sound carried by the exhaust gas is effected in the same way as in the first embodiment. Reference is therefore made to the above statements.

[0073] Here, the perforated sections 36 are again designed differently. This serves to illustrate that they can be made the same but do not have to be.

[0074] Although various embodiments have been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For that reason, the following claims should be studied to determine the true scope and content of this disclosure.