Connecting flange for connecting two tubular parts to each other

Abstract

The invention relates to a connecting flange for connecting two tubular parts to one another, preferably in an exhaust system of an internal combustion engine, comprising a flange body which surrounds a flange longitudinal axis in an annular manner and which has a first flange contact region and a second flange contact region, the second flange contact region is arranged at a distance from the first flange contact region in the direction of the longitudinal axis of the flange, a first inner circumferential contact surface is arranged in the first flange contact region, and the first inner circumferential contact surface is used for abutting the flange body against the outer circumferential surface of one of the components to be connected to each other by means of the connecting flange. A second inner circumferential contact surface is arranged on the second flange contact region, and the second inner circumferential contact surface is used for contacting the flange body on the outer circumferential surface; in the flange body, between the first inner circumferential contact surface and the second inner circumferential contact surface in the axial direction, an insulating recess which extends radially outward with respect to the first inner circumferential contact surface or / and the second inner circumferential contact surface and is open radially inward is provided.

Description

Technical Field

[0001] The invention relates to a connecting flange, by means of which two tubular components can be connected to one another in a fixed and gas-tight manner in an exhaust system of an internal combustion engine. Background Art

[0002] In order to connect tubular components in an exhaust system of an internal combustion engine used, for example, in a motor vehicle, in a fixed and gas-tight manner, it is known to provide substantially radially extending, annular connecting flanges with connecting surfaces oriented axially towards each other at the axial end regions of such tubular components which are to be positioned facing each other and fixedly connected to each other. The connecting flanges of the two tubular components can be fixedly connected to each other, for example, by means of an annular sealing element arranged in the region of their connecting flanges between the connecting surfaces of the connecting flanges, by means of screws passing through the connecting flanges or by means of a connecting clamp which surrounds the connecting flanges on the outside. Summary of the invention

[0003] The object of the present invention is to provide a connecting flange for connecting two tubular components, in particular of an exhaust system of an internal combustion engine, which connecting flange ensures a reliable and gas-tight connection of the tubular components.

[0004] According to the present invention, the object is achieved by a connecting flange according to claim 1, which is used to connect two tubular components in an exhaust device of an internal combustion engine to each other, and the connecting flange includes a flange body that annularly surrounds the longitudinal axis of the flange, the flange body having a first flange contact area and a second flange contact area, the second flange contact area being arranged at a distance from the first flange contact area in the direction of the longitudinal axis of the flange, a first inner circumferential contact surface being arranged on the first flange contact area, the first inner circumferential contact surface being used to contact the flange body against the outer circumferential surface of one of the components to be connected to each other by means of the connecting flange, and a second inner circumferential contact surface being arranged on the second flange contact area, the second inner circumferential contact surface being used to contact the flange body against the outer circumferential surface, and an insulating recess extending radially outward with respect to the first inner circumferential contact surface and / or the second inner circumferential contact surface and open radially inwardly is arranged in the flange body axially between the first inner circumferential contact surface and the second inner circumferential contact surface.

[0005] By providing two flange contact areas which are arranged at a distance from each other in the axial direction, a stable contact effect between the connecting flange and one of the tubular components to be connected via the connecting flange and thus a defined positioning of the connecting flange relative to the tubular component is achieved on the one hand. At the same time, it is possible to achieve a fixed connection of the connecting flange to the tubular component in the region of at least one of the flange contact areas. On the other hand, the insulating recess or the air or other thermally insulating material contained therein produces an insulating effect, by which the thermal load on the connecting flange is relieved. This results in the connecting flange constructed according to the invention being particularly suitable for use in areas which are subjected to strong thermal loads, such as in an exhaust system of an internal combustion engine close to the exhaust gas outlet of the internal combustion engine.

[0006] The mutual contact effect of the connecting flange and the tubular component surrounded by the connecting flange can be further improved by the following manner, that is, the first flange contact area is arranged on the first axial end area of ​​the flange body, and the second flange contact area is arranged on the second axial end area of ​​the flange body, or / and the first inner circumferential contact surface and the second inner circumferential contact surface are cylindrical surfaces, preferably cylindrical surfaces with the same radius. In particular, this design of the connecting flange constructed according to the invention is particularly suitable for use in connection with a cylindrical tubular component with a circular cross section.

[0007] In order to connect two tubular components to be connected to each other, the flange body has a flange connection area that protrudes radially outward relative to the first flange abutment area and the second flange abutment area basically in the axial direction between the first flange abutment area and the second flange abutment area, and the flange connection area has a connection area vertex that is axially located between the first flange abutment area and the second flange abutment area, and at the connection area vertex, the flange body has a maximum radial spacing from the longitudinal axis of the flange.

[0008] In order to avoid sharp-edged regions, the flange body can be curved convexly in the apex of the connection region relative to the flange longitudinal axis.

[0009] The flange body may have a first connection surface extending from the connection area vertex to the first flange abutment area and a second connection surface extending from the connection area vertex to the second flange abutment area, the first connection surface having a reduced radial spacing from the connection area vertex to the flange longitudinal axis, and the second connection surface having a reduced radial spacing from the connection area vertex to the flange longitudinal axis. These connection surfaces may be used to provide mutual connection with the other of the two tubular components or with a connection mechanism that holds the two tubular components together.

[0010] In order to achieve a defined interconnection in the region of the connecting region that is simple to realize, it is provided that the first connecting surface tapers essentially conically starting from the connecting region apex and / or the second connecting surface tapers essentially conically starting from the connecting region apex.

[0011] The gas-tight connection of the two tubular components may be assisted by providing a sealing element protruding beyond the first connection surface on the flange body substantially between the apex of the connection region and the first flange contact region in the axial direction.

[0012] A sealing element receiving recess which is open toward the first connecting surface can be provided in the flange body, so that a defined positioning of the sealing element on the flange body can be ensured. For a uniform sealing effect on the circumference, the sealing element surrounds the flange longitudinal axis substantially in an annular manner. If the sealing element is formed from a graphite material, it is particularly suitable for use in areas subject to strong thermal and chemical loads.

[0013] In order to achieve an insulating effect while still being able to provide the necessary volume for accommodating the sealing element on the flange body, it is proposed that the insulating recess has a smaller radially outward extension in its region axially overlapping the sealing element than in its region not axially overlapping the sealing element.

[0014] The present invention also relates to a connecting component, preferably a connecting component for an exhaust system of an internal combustion engine, comprising a first tubular component and at least one connecting flange constructed according to the present invention, wherein the connecting flange abuts against the outer peripheral surface of the first tubular component with its first inner peripheral abutment surface and its second inner peripheral abutment surface.

[0015] The at least one connecting flange can be firmly held together with the first tubular component by being fixedly connected to the first tubular component in the region of at least one of the first flange contact region and the second flange contact region by material bonding, preferably welding.

[0016] In order to avoid mechanical stresses in the event of different strong thermal expansions of the at least one connecting flange on the one hand and the first tubular component on the other hand, it is proposed that the at least one connecting flange is fixedly connected to the first tubular component only in the region of one of the first flange contact region and the second flange contact region. In the other flange contact region, the flange body is supported on the outer circumference of the first tubular component but is substantially freely movable in the axial direction relative to the first tubular component.

[0017] In a particularly advantageous embodiment, it can be provided that the at least one connecting flange is fixedly connected to the first tubular component in the region of the second flange contact region. Thus, the first flange contact region located closer to the sealing element and therefore also the region in which the sealing element provided for interaction with the other tubular component is located can be moved axially relative to the first tubular component.

[0018] The invention further relates to an exhaust system for an internal combustion engine, comprising a connecting assembly designed according to the invention and at least one second tubular component connected to the first tubular component by means of the at least one connecting flange.

[0019] In order to be connected to the at least one connecting flange, the second tubular component has a mating connection area, and the mating connection area has a mating connection surface, which is used to connect with one of the first connection surface and the second connection surface of the at least one connecting flange.

[0020] In order to assist in the defined positioning of the two tubular components to be connected to each other, it is proposed that the mating connection surface is preferably conically radially widened in the direction of the axial end of the second tubular component. This makes it possible to hold the two tubular components in a radially centered position relative to each other via the mutually supporting conical connection surfaces.

[0021] Holding the two tubular components fixedly together can be achieved, for example, in the following manner: the first tubular component and the second tubular component are held in contact with each other in the connected state by a connecting mechanism, preferably a connecting clamp, which annularly surrounds the connecting area of ​​the at least one connecting flange and the mating connecting area of ​​the second tubular component. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0023] Figure 1 A longitudinal sectional view of a connection assembly is shown, the connection assembly having a tubular component and a connection flange arranged thereon;

[0024] Figure 2 The connecting assembly is shown when connected to another tubular component. Figure 1 The connection components in Figure 1 Detail view of area II. DETAILED DESCRIPTION

[0025] exist Figure 110 is a connection assembly which can be used in an exhaust system of an internal combustion engine. The connection assembly 10 comprises a first tubular component 12 which, in the illustrated design example, has two essentially cylindrical regions 14, 16 which have different diameters relative to one another with respect to a longitudinal axis L. In the region 16 with a smaller diameter, a connection flange 20 is arranged on an outer circumference 18 of the first tubular component 12. The connection flange 20 is arranged in such a way that it annularly surrounds a longitudinal axis L of the first tubular component 12 which corresponds to the flange longitudinal axis F in the assembled state, i.e., it forms a closed ring which surrounds the outer circumference 18 over its entire circumferential extension region around the longitudinal axis L.

[0026] The connecting flange 20 includes a flange body 22 constructed of a metal material. A first flange contact area 24 and a second flange contact area 26 are constructed on the flange body 22 in a manner spaced axially apart from each other. The flange body 22 provides a first inner peripheral contact surface 28 in the first flange contact area 24, with which the flange body 22 contacts the outer peripheral surface 18 of the first tubular component 12. The flange body 22 provides a second inner peripheral contact surface 30 in the second flange contact area 26, with which the flange body 22 also contacts the outer peripheral surface 18 of the first tubular component 12.

[0027] In order to adapt to the shape of the first tubular component 12, in particular in its region 16 provided for receiving the connecting flange 20, the first inner circumferential contact surface 28 and the second inner circumferential contact surface 30 are designed as cylindrical surfaces, which can also have a circular cross-sectional geometry, i.e. can be designed as cylindrical surfaces, in a manner adapted to the first tubular component 12, in particular in its region 16, for example, a circular cross-sectional geometry. This ensures that in both flange contact regions 24, 26, at a first axial end region 32 of the flange body 22 having the first flange contact region 24 and at a second axial end region 34 of the flange body 22 having the second flange contact region 26, a stable, flat contact is produced between the flange body and the first tubular component 12.

[0028] The fixed connection of the flange body 22 to the first tubular component 12 is only carried out in the region of the second flange contact region 26 or the second axial end region 34 which is further away from the axial end 36 of the first tubular component 12. For this purpose, a preferably uninterrupted continuous weld 38 can be produced in the circumferential direction about the longitudinal axis L. Therefore, in the region of the first flange contact region 24 or the first axial end region 32, the flange body 22 which is also supported there on the outer circumferential surface 18 of the first tubular component 12 can in principle be moved or displaced substantially freely in the axial direction relative to the first tubular component 12.

[0029] In the flange body 22, an insulating recess 40 is formed axially between the two flange contact areas 24, 26 or the two axial end areas 32, 34 of the flange body 22. Starting from the radial level of the two inner circumferential contact surfaces 28, 30 at the same radial distance from the flange longitudinal axis F, the insulating recess 40 extends radially outward and is basically open radially inward, or the insulating gap is covered radially inward in the connecting flange 20 mounted on the first tubular component 12 by the section of the outer circumferential surface 18 of the first tubular component 12 between the two axial end areas 32, 34 of the flange body 22.

[0030] In the assembled state, air or, if appropriate, another insulating material, such as a foamed insulating material or the like, is present in the insulating recess 40, whereby thermal insulation of the flange body 22 is achieved, in particular in the region of a flange connection region 42 between the two flange contact regions 24, 26. The flange body 22 extends radially further outwards between the two flange contact regions 24, 26 with this flange connection region 42. At the connection region point 44, the flange connection region 42 or the flange body 22 has a maximum radial spacing from the flange longitudinal axis F.

[0031] Immediately after the first flange contact area 24, the flange connection area 42 provides a first connection surface 46, which tapers preferably substantially conically from the connection area apex 44 in the direction of the first flange contact area 24. Likewise, the flange connection area 42 provides a second connection surface 48 between the connection area apex 44 and the second flange contact area 26, which tapers preferably substantially conically from the connection area apex 44 in the direction of the second flange contact area 26. In order to avoid a sharp transition of the two connection surfaces 46, 48 that are to extend substantially V-shaped toward each other, the flange connection area 42 is convexly curved in the region of the connection area apex 44 with respect to the flange longitudinal axis F.

[0032] In the area between the connection area vertex 44 and the first flange contact area 24 of the flange body 22 or the flange connection area 42, a sealing element 5, for example made of graphite material, is arranged, preferably as a closed ring, surrounding the flange longitudinal axis L. This sealing element is accommodated in a sealing element receiving recess 52 open to the first connection surface 46 and is held therein, for example, by a press fit. The sealing element 50 protrudes with its sealing surface area 54 beyond the first connection surface 46 in order to be able to exert a sealing effect with the sealing surface area 54 of the flange body 22. Figure 2 The mutual sealing effect of the second tubular member 56 can be seen in FIG.

[0033] In order to be able to provide the volume required for accommodating the sealing element 50 in the flange body 22 without having to oversize the flange body 22, the insulating slot 40 is designed with a smaller radial extension in the region in which it axially overlaps the sealing element 50 or the sealing element accommodating slot 52 than in the axially following region in which the insulating slot 40 does not axially overlap the sealing element 50 or the sealing element accommodating slot 52. In this region, there can be a radial overlap between the insulating slot 40 and the sealing element 50 or the sealing element accommodating slot 52.

[0034] Figure 2 Description: How the two tubular components 12 and 56 of the exhaust system, which are generally designated by 58, are connected to each other in a gas-tight manner using a connecting flange 20. The second tubular component 56 has a mating connection region 62, which is produced, for example, by radial widening, in its axial end region 60 to be connected in a gas-tight manner to the first tubular component 12 and has a mating connection surface 64. In an adaptation to the shape of the first connecting surface 46 of the connecting flange 20, the mating connection surface 64 can also have a substantially conical shape.

[0035] In the connected state, the second tubular component 56 rests with the mating connection surface 64 on the connecting flange 20 or the first connecting surface 46 while compressing the sealing element 50. In this state, the two tubular components 12, 56 are fixedly held together by the connecting means 66 which annularly surrounds the connecting flange 20 or the mating connection area 62 radially on the outside. This connecting means is, for example, configured as a connecting clamp or a pipe clamp, which rests with the corresponding leg areas 68, 70 on the mating connection area 62 or the second connecting surface 48 of the connecting flange 20 and clamps the mating connection area 62 axially to the connecting area 42 of the connecting flange 20 by its circumferential clamping.

[0036] On the one hand, because the connecting flange 20 is well thermally insulated, in particular in its flange connection region 42, by providing the insulating recesses 40, from the section of the first tubular component 12 extending in this region, and on the other hand, because the first flange contact region 24 and the section of the flange connection region 42 adjacent thereto, in which the first connection surface 46 is also provided, are substantially freely movable in the axial direction relative to the first tubular component 12, a relatively intense heating of the connecting flange 20 via the second tubular component 56 cannot lead to an overload of the connecting flange 20 or of its fixed connection to the first tubular component 12. If, during operation, thermal length changes of varying intensity occur between the connecting flange 20 and the first tubular component 12, the connecting flange 20 can be displaced axially relative to the first tubular component 12 with its first flange contact region 24. Due to this property, the connecting flange 20 designed according to the invention is particularly suitable for use in such a region of the exhaust system 58, in which a strong thermal load is generated by the exhaust gas discharged by the internal combustion engine by means of the second tubular component 56 positioned relatively close to the internal combustion engine. Likewise, the connecting flange 20 can also be used in other areas of the exhaust system or in areas which are less thermally loaded.

Claims

1. A connecting flange for connecting two tubular components (12, 56) in an exhaust system (58) of an internal combustion engine, the connecting flange comprising a flange body (22) annularly surrounding a flange longitudinal axis (F), the flange body having a first flange contact area (24) and a second flange contact area (26), the second flange contact area being arranged at a distance from the first flange contact area (24) in the direction of the flange longitudinal axis (F), wherein: A first inner circumferential abutment surface (28) is provided in the first flange abutment area (24), the first inner circumferential abutment surface being used to abut the flange body (22) against the outer circumferential surface (18) of one of the components (12, 56) to be connected to each other by means of the connecting flange (20), and a second inner circumferential abutment surface (30) is provided in the second flange abutment area (26), the second inner circumferential abutment surface being used to abut the flange body (22) against the outer circumferential surface (18), and an insulating recess (40) is provided in the flange body (22) axially between the first inner circumferential abutment surface (28) and the second inner circumferential abutment surface (30), extending radially outward with respect to the first inner circumferential abutment surface (28) and / or the second inner circumferential abutment surface (30) and open radially inward.

2. The connecting flange according to claim 1, characterized in that: The first flange abutment area (24) is arranged on a first axial end area (32) of the flange body (22), and the second flange abutment area (26) is arranged on a second axial end area (34) of the flange body (22), or / and the first inner circumferential abutment surface (28) and the second inner circumferential abutment surface (30) are cylindrical surfaces, preferably cylindrical surfaces having the same radius as each other.

3. The connecting flange according to claim 1 or 2, characterized in that: The flange body (22) has a flange connection area (42) that protrudes radially outward relative to the first flange abutment area (24) and the second flange abutment area (26) essentially between the first flange abutment area (24) and the second flange abutment area (26) in the axial direction, and the flange connection area has a connection area vertex (44) that is axially located between the first flange abutment area (24) and the second flange abutment area (26), and at the connection area vertex (44), the flange body (22) has a maximum radial spacing from the flange longitudinal axis (F).

4. The connecting flange according to claim 3, characterized in that: The flange body (22) is curved convexly in a connection region apex (44) relative to the flange longitudinal axis (F).

5. The connecting flange according to claim 3 or 4, characterized in that: The flange body (22) has a first connecting surface (46) extending from the apex (44) of the connecting area to the first flange abutment area (24) and a second connecting surface (48) extending from the apex (44) of the connecting area to the second flange abutment area (26), the first connecting surface having a decreasing radial spacing from the apex (44) of the connecting area to the longitudinal axis (F) of the flange, and the second connecting surface having a decreasing radial spacing from the apex (44) of the connecting area to the longitudinal axis (F) of the flange.

6. The connecting flange according to claim 5, characterized in that: The first connection surface (46) tapers substantially conically starting from the connection region apex (44), and / or the second connection surface (48) tapers substantially conically starting from the connection region apex (44).

7. The connecting flange according to claim 5 or 6, characterized in that: A sealing element (50) is provided on the flange body (22) substantially between the apex (44) of the connection area and the first flange contact area (24) in the axial direction and protrudes beyond the first connection surface (46).

8. The connecting flange according to claim 7, characterized in that: A sealing element receiving recess (52) open toward the first connecting surface (46) is provided in the flange body (22), or / and the sealing element (50) surrounds the flange longitudinal axis (F) substantially annularly, or / and the sealing element (50) is formed from a graphite material.

9. The connecting flange according to claim 7 or 8, characterized in that: The insulating recess (40) has a smaller radially outward extension in a region in which it overlaps the sealing element (50) in the axial direction than in a region in which it does not overlap the sealing element (50) in the axial direction.

10. A connecting component, preferably a connecting component for an exhaust system (50) of an internal combustion engine, comprising a first tubular component (12) and at least one connecting flange (20) according to any one of claims 1 to 9, wherein the connecting flange abuts against the outer peripheral surface (18) of the first tubular component (12) with its first inner peripheral abutment surface (28) and its second inner peripheral abutment surface (30).

11. The connection assembly according to claim 10, characterized in that The at least one connecting flange (20) is fixedly connected to the first tubular component (12) in the region of at least one of a first flange contact region (24) and a second flange contact region (26) by material bonding, preferably welding.

12. The connection assembly according to claim 10 or 11, characterized in that: The at least one connecting flange (20) is fixedly connected to the first tubular component (12) only in the region of one of the first flange contact region (24) and the second flange contact region (26).

13. The connection assembly according to claim 12 in combination with claim 7, characterized in that: The at least one connecting flange (20) is fixedly connected to the first tubular component (12) in the region of the second flange contact region (26).

14. An exhaust system for an internal combustion engine, comprising a connection assembly (10) according to any one of claims 10 to 13 and at least one second tubular component (56) connected to the first tubular component (12) by means of the at least one connecting flange (20).

15. The exhaust device according to claim 14, characterized in that The second tubular component (56) has a mating connection area (62), wherein the mating connection area has a mating connection surface (64), and the mating connection surface is used to connect with one of the first connection surface (46) and the second connection surface (48) of the at least one connecting flange (20).

16. The exhaust device according to claim 15, characterized in that The mating surface (64) is preferably designed to widen radially in a conical manner in the direction of an axial end of the second tubular part (56).

17. The exhaust device according to claim 15 or 16, characterized in that: The first tubular component (12) and the second tubular component (56) are held in contact with each other in the connected state by a connecting means (66), preferably a connecting clamp, which annularly surrounds a connecting area (42) of the at least one connecting flange (20) and a mating connecting area (62) of the second tubular component (56).

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