Exhaust valve

Abstract

The present invention relates to an exhaust valve, in particular for the exhaust flow of an internal combustion engine, the exhaust valve comprising a valve tube (14), a valve baffle supported inside the valve tube (14) on a pivot shaft (18) rotatable about a pivot axis (A), the pivot shaft (18) being rotatably supported on the valve tube (14) in each of its two axial end regions (30) by means of a bearing arrangement structure, the pivot shaft (18) being constructed in a first axial end region for coupling to a drive mechanism of a pivot drive device, characterized in that the pivot shaft (18) is in contact with a damping material (56) supported relative to the valve tube (14) in at least one axial end region (30).

Description

Technical Field

[0001] The present invention relates to an exhaust valve, which is particularly used for the exhaust flow of an internal combustion engine. The exhaust valve comprises a valve tube, a valve baffle supported inside the valve tube on a pivot shaft that can rotate about a pivot axis, the pivot shaft being rotatably supported on the valve tube in each of its two axial end regions by means of a bearing arrangement structure, and the pivot shaft being constructed in a first axial end region for coupling to a drive mechanism of a pivot drive device. Background Art

[0002] Such an exhaust valve is known from DE 10 2016 114 704 A1. In such an exhaust valve, the pivot shaft is supported pivotably about a pivot axis in the region of its two axial ends in corresponding bearings arranged on the valve tube or in pivot bearings arranged therein. During the deflection of the pivot shaft triggered by the pivot drive, friction is generated in the region of the pivot bearing, which is usually designed as a sliding bearing. This friction can lead to vibration excitation of the pivot shaft and therefore also in particular to vibration excitation of the coupling arrangement that couples the pivot shaft to the pivot drive. This vibration excitation in the region of the pivot shaft or the coupling arrangement can lead to the emission of sounds that can be perceived in the vehicle. Summary of the invention

[0003] The object of the present invention is to provide an exhaust flap in which the emission of sounds generated by vibrations in the region of the exhaust flap is suppressed.

[0004] According to the present invention, the task is achieved by an exhaust valve, which is particularly used for the exhaust flow of an internal combustion engine, and which includes a valve tube, a valve baffle supported inside the valve tube on a pivot shaft that can rotate about a pivot axis, the pivot shaft being rotatably supported on the valve tube in each of its two axial end regions by means of a bearing arrangement structure, and the pivot shaft is constructed in a first axial end region for coupling to a drive mechanism of a pivot drive device.

[0005] The exhaust flap according to the invention is characterized in that the pivot axis, in at least one axial end region, is in contact with a damping material which is supported relative to the flap tube.

[0006] By arranging a vibration-damping material in the region of at least one axial end region of the pivot shaft, the formation of vibration excitation in the region of the pivot shaft is substantially suppressed, or vibrations that may be formed in the region of the exhaust valve or transmitted to the exhaust valve do not substantially lead to sound emissions.

[0007] For outstanding damping properties, it is proposed that the vibration-damping material comprises a porous material. In this context, it has proven to be particularly suitable to use an open-porous material for the vibration-damping material.

[0008] Since very high temperatures usually prevail in the region of such exhaust flaps, it is proposed that the damping material comprises a wire material, thereby ensuring a temperature-resistant construction.

[0009] Due to the adjustable structure in order to obtain a defined damping characteristic, it is particularly advantageous for the wire material to include a wire mesh, a wire knit, a wire fabric or a wire cloth. Such a material can be provided on the one hand by selecting the wire raw material and on the other hand by adjusting the production parameters with a defined structure, in particular with a defined density of the wire material. Alternatively, a wire disorder material can be used for the wire material, in which there is a substantially irregular course of the wire segments forming the material. Such a wire disorder material can be provided, for example, as so-called wire wool.

[0010] In one easily realizable embodiment, it is provided that the pivot axis is in contact with the damping material in the region of its second axial end.

[0011] In order to achieve both a defined support in the second axial end region of the pivot shaft and a contact between the pivot shaft and the damping material in a structurally simple and compact manner, it is proposed that the second bearing arrangement provided in association with the second axial end region of the pivot shaft comprises a second bearing shell provided on the valve tube and a second pivot bearing, for example a sliding bearing, provided in the second bearing shell and radially supporting the pivot shaft with respect to the pivot axis, and the damping material is provided axially between the pivot shaft and the bearing shell bottom. Such an arrangement of the damping material is possible in particular when the second pivot bearing is used only for radially supporting the pivot shaft but not for axially supporting the pivot shaft.

[0012] In order to achieve a defined interaction of the damping material with the pivot shaft on the one hand and a defined positioning of the damping material in the bearing shell on the other hand, it is proposed that the damping material comprises a damping material contact area which contacts the pivot shaft on the axial end side in the second axial end area and a damping material fixing area which is mounted on the bottom of the bearing shell.

[0013] In order to achieve the largest possible interaction surface between the damping material and the pivot shaft, the damping material contact area can have a pivot shaft engagement area that protrudes axially in the direction of the axial end side of the pivot shaft, and a damping material receiving recess for accommodating the pivot shaft engagement area can be provided on the axial end side of the pivot shaft.

[0014] Here, the pivot axis engagement area can, for example, be at least partially convexly curved or conical or truncated-conical in structure, and the damping material receiving recess can be shaped complementary to the pivot axis engagement area. This means that, for example, in the case of a convex, dome-shaped structure of the pivot axis engagement area, the damping material receiving recess is concavely curved with its complementary design. The same also applies to conical or truncated-conical designs or other geometric shapes. The pivot axis engagement area can, for example, also be partially truncated-conical in structure and in its end area or tip area with a convex dome design, and then a complementary structure is provided in the damping material receiving recess. The pivot axis engagement area can, for example, be truncated-spherical in structure.

[0015] In an alternative design, the arrangement of the receiving recess and the engagement region can be reversed to the previously described recess. Thus, the damping material contact region can have a pivot shaft receiving recess, and a damping material engagement region can be provided on the axial end side of the pivot shaft, which engages in the pivot shaft receiving recess.

[0016] In this arrangement, the damping material engagement region can also be at least partially convexly curved or conical or truncated-conical in order to achieve the least frictional interaction possible, and the pivot axis receiving recess can be shaped complementary to the damping material engagement region. The damping material engagement region can also be shaped, for example, in the form of a spherical segment.

[0017] In order to spatially separate the functions of fixing on the one hand and contacting with the pivot axis on the other hand, it is proposed that the damping material fixing area projects radially outward relative to the damping material contact area or / and is arranged to at least partially surround the damping material contact area radially outward. Alternatively or additionally, the damping material fixing area may be arranged in the axial extension of the damping material contact area, that is, substantially on its back side.

[0018] For stable support of the damping material on the bearing shell base, the damping material fastening region can be designed in the form of a plate.

[0019] Thermally stable fixing of the damping material can be achieved, for example, by attaching the damping material fixing region to the bearing shell base by material bonding, preferably welding.

[0020] For a defined positioning of the pivot shaft relative to the valve tube, it is further proposed that a first bearing arrangement arranged in association with a first axial end region of the pivot shaft comprises a first bearing shell arranged on the valve tube and a first pivot bearing, preferably a sliding bearing, arranged on the first bearing shell and supporting the pivot shaft radially and axially relative to the pivot axis. Since the first pivot bearing also specifies or specifies solely a defined positioning of the pivot shaft in the axial direction in addition to the radial supporting function, on the one hand, overdetermination in the axial positioning is avoided, and on the other hand, the possibility of axial interaction between the pivot shaft and the damping material is provided in the region of the second bearing arrangement.

[0021] The exhaust flap advantageously further comprises a pivot drive for the pivot shaft, which comprises a drive mechanism which is coupled to the pivot shaft by means of a coupling arrangement for joint rotation about a pivot axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is described in detail below with reference to the accompanying drawings.

[0023] Figure 1 An exhaust valve for an exhaust system of an internal combustion engine is shown;

[0024] Figure 2 A detailed sectional view showing a bearing region which supports the pivot axis of the exhaust flap in the axial end region remote from the pivot drive;

[0025] Figure 3 An alternative design is shown corresponding to Figure 2 pictorial diagram;

[0026] Figure 4 Another alternative design corresponds to Figure 2 . DETAILED DESCRIPTION

[0027] Figure 1 A side view of an exhaust flap, generally designated 10 and which can be installed, for example, in an exhaust system of an internal combustion engine, is shown with a flap drive 12. The exhaust flap 10 comprises a flap tube 14 in which a flap diaphragm, generally designated 16, is supported on a pivot axis 18 so as to be pivotable about a pivot axis A. The flap diaphragm 16 comprises two flap blades 20, 22 which, when the flap diaphragm 16 is positioned in the locked position, rest against blade stops 24, 26 arranged on the inner circumference of the flap tube 14.

[0028] The pivot shaft 18 is supported rotatably or pivotably about the valve tube 14 at its two axial end regions 28, 30. The pivot shaft 18 is coupled to a drive mechanism 34, such as a drive shaft, of the valve drive 12 in its first axial end region 28 by means of a coupling arrangement 32 for joint rotation. In this region, the pivot shaft 18 can be coupled to the coupling arrangement 32 directly or via a component that is non-rotatable with it. The coupling arrangement 32 can, for example, include a coupling element 36 formed of sheet metal, flexible, and axially biasing the pivot shaft 18 and the drive mechanism 34 away from each other in the direction of the pivot axis A, which can be coupled to the pivot shaft 18 and the drive mechanism 34, for example, by a positive locking engagement, for joint rotation about the pivot axis A.

[0029] The pivot shaft 18 is supported in its two axial end regions 28, 30 on the flap tube 14 so as to be rotatable about the pivot axis A by means of corresponding bearing arrangements 38, 40. Figure 1 The bearing arrangement 38, which can be seen above and is positioned close to the pivot drive 12, comprises a bearing shell 42 arranged on the valve tube 14 and fixed, for example, by welding. The first axial end region 28 of the pivot shaft 18 extends through the first bearing shell 42 and protrudes axially beyond it, so that a rotational coupling projection 44 arranged on the first axial end region 28 can engage in a corresponding rotational coupling recess of the coupling element 36. The rotational coupling projection 46 arranged on the drive shaft of the pivot drive 12, which acts as the drive mechanism 34, engages in a corresponding manner in the rotational coupling recess of the coupling element 36.

[0030] A first pivot bearing (not shown in the drawing) is arranged in the first bearing shell 42 and supports the pivot shaft 18 both radially with respect to the pivot axis A and axially in the direction of the pivot axis A. The first pivot bearing can be designed, for example, as a sliding bearing and therefore also serves for a defined axial positioning of the pivot shaft 18 in the valve tube 14 under an axial preload generated for the pivot shaft 18 by means of the coupling element 36 .

[0031] The pivot axis 18 is located at its second axial end region 30. Figure 2The second bearing arrangement 40 shown in detail in the drawing is rotatably supported about the pivot axis A. The second bearing arrangement 40 comprises a second bearing shell 48, which can be mounted on the valve tube 14, for example by welding. The pivot shaft 18 extends through an opening provided in the valve tube 14 into the second bearing shell 48. A second pivot bearing 50 is provided in the second bearing shell 48, by means of which the pivot shaft 18 is supported radially about the pivot axis A in its second axial end region 30 and is therefore rotatably supported. There is no axial support or supporting effect between the second axial end region 30 of the pivot shaft 18 and the second pivot bearing 50, so that overdetermination in the axial positioning of the pivot shaft 18 is avoided. The second pivot bearing 50 can also be configured as a sliding bearing, for example.

[0032] The second bearing shell 48 is closed at its end facing away from the valve tube 14 by a bearing shell bottom 52. The cap-shaped bearing shell bottom 52 can be inserted, for example pressed, into the axially open end of the second bearing shell 48 and / or connected to the second bearing shell in a materially bonded manner, for example by welding.

[0033] A damping material 56 is arranged on the inner side 54 of the second axial end region 30 of the bearing shell bottom 52 facing the pivot axis 18. This damping material 56, which is preferably provided as an integrated body, comprises in a region centered with respect to the pivot axis A a damping material contact region 57 with a pivot axis engagement region 58 and radially outwardly a damping material fastening region 60 which preferably completely surrounds the damping material contact region 57.

[0034] In the plate-shaped damping material fastening region 60, the damping material 56 is fastened to the inner side 54 of the bearing shell base 52 at a radial distance from the pivot axis engagement region 58, for example by a plurality of weld points 62. This can be done before the bearing shell base 52 is mounted on the bearing shell 48.

[0035] The pivot axis engagement region 58, which projects axially via the plate-shaped damping material fastening region 60 in the direction of the pivot axis 18, is curved convexly, for example in the form of a spherical segment, and engages in damping material receiving recesses 66 formed on the axial end side 64 of the pivot axis 18. These damping material receiving recesses are formed complementary to the shape of the pivot axis engagement region 58 and are therefore also curved concavely.

[0036] The damping material 56 is in contact with the second axial end region 30 of the pivot shaft 18 with the pivot axis engagement region 58. The damping material 56 is, for example, made of a wire material, preferably a wire mesh or the like and therefore has a porous, flexible structure in principle, so that when the bearing shell base 52, which already carries the damping material 56, is mounted on the second bearing shell 48, the pivot axis engagement region 58 is positioned in such a way that it engages in the damping material receiving recess 66 and rests against the second axial end region 30 of the pivot shaft 18 under axial prestress. Due to this contact between the damping material 56 and the pivot shaft 18, the formation of vibrations during a rotation or deflection of the pivot shaft 18 about the pivot axis A is suppressed or damped outwardly or the emission of sound is suppressed. Therefore, during the operation of the exhaust flap 10, no vibrations or vibration excitations are generated, which, for example, could also be transmitted to the coupling element 36 made of a sheet metal and could be emitted outwardly by the coupling element in the form of sound. Vibrations which are possibly transmitted to the exhaust flap 10 during operation can also be damped in this way and thus substantially do not lead to the emission of any sound in the region of the exhaust flap 10 .

[0037] In the exhaust flap 10 designed according to the invention, as an alternative to the illustrated and previously described design, the contact between the pivot axis 18 and the damping material 56 can also be achieved in that the pivot axis 18 engages with its axial end, for example, a convex damping material engagement region protruding axially thereon, for example in the form of a spherical segment, in a complementary recess formed in the damping material 56. This recess can already be present in the damping material 56 before the contact with the pivot axis 18 is produced, but can also be formed, for example, by pressing the pivot axis 18 into the damping material 56. In this case, the damping material 56 arranged or mounted on the bearing shell bottom 52 can be designed in a particularly simple design to be plate-shaped over its entire radial extension and with a substantially uniform axial thickness.

[0038] Figure 3 An alternative design is shown. Figure 3 In the embodiment shown in FIG. 5 , the pivot axis engagement region 58 is shaped in a frustoconical manner. Correspondingly, the damping material receiving recess 66 is shaped in a complementary frustoconical manner in the pivot axis 18 .

[0039] It should be pointed out that: Figure 2 and Figure 3 Combinations of the designs shown in are also possible, for example, so that Figure 3 In the truncated cone-shaped design shown in FIG. 1 , the pivot axis engagement area 58 is not flat at its upper end, but is formed in a manner similar to that in FIG. Figure 2 Other shapes, for example a conical shape of the pivot axis engagement area 58, are also possible.

[0040] Another alternative design is Figure 4 . In this embodiment, the damping material contact area 57 is designed with a concave dome-shaped pivot axis receiving recess 66', while a convexly domed damping material engagement area 58' is formed on the axial end side 64 of the pivot axis 18, which engages in a complementarily shaped pivot axis receiving recess 66'. In particular, in the case of a flexible embodiment of the damping material 56, the pivot axis receiving recess 66' can be formed completely or also partially by pressing the damping material engagement area 58' into the damping material 56.

[0041] It should be pointed out that: Figure 4 In the embodiment shown in FIG. 5 , other shapes of the damping material engagement area 58 ′ or the pivot axis receiving recess 66 ′ are also possible. Thus, it is also possible to provide truncated cone-shaped, conical or combined shapes with different geometric structures, such as truncated cone-shaped and dome-shaped geometries.

Claims

1. An exhaust valve, the exhaust valve comprising a valve tube (14), a valve diaphragm (16) supported inside the valve tube (14) on a pivot shaft (18) rotatable about a pivot axis (A), the pivot shaft (18) being rotatably supported on the valve tube (14) in each of its two axial end regions by means of a bearing arrangement structure, the pivot shaft (18) being configured in a first axial end region (28) for coupling to a drive mechanism (34) of a pivot drive device (12), the pivot shaft (18) being in contact with a damping material (56) supported relative to the valve tube (14) in a second axial end region (30), and being in contact with a second axial end region (30) of the pivot shaft (18) The second bearing arrangement (40) arranged in association with the end region (30) comprises a second bearing shell (48) arranged on the valve tube (14) and a second pivot bearing (50) arranged in the second bearing shell (48) and radially supporting the pivot shaft (18) about the pivot axis (A), and the damping material (56) is arranged axially between the pivot shaft (18) and the bearing shell bottom (52) of the second bearing shell (48), the damping material (56) comprising a damping material contact area (57) contacting the pivot shaft (18) on the axial end side (64) in the second axial end region (30) and a damping material fixing area (60) mounted on the bearing shell bottom, and: the damping material contact region (57) has a pivot axis engagement region (58) which projects axially in the direction of the axial end side (64) of the pivot axis (18), and a damping material receiving recess (66) for receiving the pivot axis engagement region (58) is provided on the axial end side (64) of the pivot axis (18), or The damping material contact region (57) has a pivot axis receiving recess (66'), and a damping material engagement region (58') is provided on the axial end side (64) of the pivot axis (18) and engages in the pivot axis receiving recess (66').

2. The exhaust valve according to claim 1, characterized in that The vibration damping material (56) comprises a porous material.

3. The exhaust valve according to claim 2, characterized in that The vibration dampening material (56) comprises an open-porous material.

4. The exhaust valve according to any one of claims 1 to 3, characterized in that The vibration dampening material (56) comprises a wire material.

5. The exhaust valve according to claim 4, characterized in that The metal wire material comprises a metal wire mesh, a metal wire knitted fabric, a metal wire braided fabric, a metal wire cloth or a metal wire disordered material.

6. The exhaust valve according to any one of claims 1 to 3, characterized in that The second pivot bearing (50) is a sliding bearing.

7. The exhaust valve according to any one of claims 1 to 3, characterized in that The pivot axis engagement region (58) is at least partially convexly curved or conical or frustoconical in shape, and the damping material receiving recess (66) is shaped complementary to the pivot axis engagement region (58).

8. The exhaust valve according to claim 7, characterized in that The pivot axis engagement region (58) is designed in the form of a spherical segment.

9. The exhaust valve according to any one of claims 1 to 3, characterized in that The damping material engagement region (58') is at least partially convexly curved or conical or truncated-conical, and the pivot axis receiving recess (66') is shaped complementary to the damping material engagement region (58').

10. The exhaust valve according to claim 9, characterized in that The damping material engagement region (58') is designed in the form of a spherical segment.

11. The exhaust flap according to claim 1, wherein the damping material fastening region (60) projects radially outward relative to the damping material contact region (57) or / and is arranged to at least partially surround the damping material contact region (57) radially outward.

12. The exhaust valve according to any one of claims 1 to 3, characterized in that The damping material fastening region (60) is designed in a plate-like manner.

13. The exhaust valve according to any one of claims 1 to 3, characterized in that The damping material fastening region (60) is attached to the bearing shell base (52) by material bonding.

14. The exhaust valve according to claim 13, characterized in that The damping material fastening region (60) is mounted on the bearing shell base (52) by welding.

15. The exhaust valve according to any one of claims 1 to 3, characterized in that A first bearing arrangement (38) arranged in conjunction with a first axial end region (28) of the pivot shaft (18) comprises a first bearing shell (42) arranged on the valve tube (14) and a first pivot bearing arranged in the first bearing shell (42) and supporting the pivot shaft (18) radially and axially with respect to the pivot axis (A).

16. The exhaust valve according to claim 15, characterized in that The first pivot bearing is a sliding bearing.

17. The exhaust valve according to any one of claims 1 to 3, characterized in that The pivot drive (12) comprises a drive mechanism (34) coupled to the pivot shaft (18) by means of a coupling arrangement (32) for joint rotation about a pivot axis (A).

18. The exhaust flap according to any one of claims 1 to 3, characterized in that The exhaust flap is provided for an exhaust gas flow of the internal combustion engine.

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