Contact welding device

Abstract

Contact welding device (10) for simultaneously welding at least three components (5.1, 5.2, 5.3) together by means of a current pulse, comprising: a first electrode (1) with a first contact surface (1.1) for contact with the first component (5.1) and a second electrode (2) with a second contact surface (2.1) for contact with the second component (5.3), wherein the first electrode (1) is separated from the second electrode (2) and the first electrode (1) can be configured as an anode or cathode and the second electrode (2) can be configured as an anode or cathode, wherein a short-circuit conductor (3) with two third contact surfaces (3.1) for contact with at least the third component (5.1).2) is provided, wherein a direction of movement R13 is provided in which the first electrode (1) is movable relative to the short-circuit conductor (3), and wherein a direction of movement R23 is provided in which the second electrode (2) is movable relative to the short-circuit conductor (3), wherein a distance a1 between the first contact surface (1.1) and the short-circuit conductor (3) can be reduced by the movement in the direction of movement R13, and wherein a distance a2 between the second contact surface (2.1) and the short-circuit conductor (3) can be reduced by the movement in the direction of movement R23, characterized in that the short-circuit conductor (3) has a cylindrical central axis (3.5) and the first contact surface (1.1) is annular in relation to the cylindrical central axis (3.5) and / or the second contact surface (2.1) is annular in relation to the cylindrical central axis (3.5).

Description

[0001] The invention relates to a contact welding device for simultaneously welding at least three components together by means of a current pulse, comprising a first electrode with a first contact surface for attachment to a first component and a second electrode with a second contact surface for attachment to a second component, wherein the first electrode is separated from the second electrode and the first electrode can be formed into an anode or cathode and the second electrode can be formed into an anode or cathode.

[0002] Furthermore, the invention relates to an exhaust device comprising a housing shell, a first housing cover and a second housing cover, wherein the housing shell is materially bonded to the first housing cover via a first weld seam and the housing shell is materially bonded to the second housing cover via a second weld seam.

[0003] Furthermore, the invention relates to a method for welding three components together to form a workpiece using a contact welding device.

[0004] A contact welding device is known from US Patent 6,791,051 B2. This device has two electrodes between which two components are welded. The two electrodes are movable relative to each other to generate a deformation before the welding process. Before the welding process, the electrodes are moved axially into one another, thereby radially pressing the components together so that they ultimately rest radially against the contact surface of the second electrode.

[0005] Furthermore, a contact welding device is already known from US 7,476,824 B4. This device consists of two electrodes, one of which is movable in an axial direction relative to the other. The two electrodes have several segments or sections between which two components are axially pressed and welded.

[0006] The invention is based on the objective of designing and arranging a contact welding device in such a way that efficient welding of several components is made possible.

[0007] The problem is solved according to the invention by providing a short-circuit conductor with at least a third contact surface for mounting at least a third component, wherein a direction of movement R13 is provided in which the first electrode is movable relative to the short-circuit conductor, and a direction of movement R23 in which the second electrode is movable relative to the short-circuit conductor, wherein a distance a1 between the first contact surface and the short-circuit conductor can be reduced by movement in direction R13, and wherein a distance a2 between the second contact surface and the third contact surface can be reduced by movement in direction R23. Advantageously, at least one of the electrodes, or even just one of the electrodes, such as the second electrode, is actively mounted so that a contact force can be generated between the three components to be connected.This clamping force can be achieved through the weight of the electrode or by a separate drive. In this regard, it is also highly advantageous if the short-circuit conductor is mounted only passively, allowing for a settling movement during the welding process. This enables three components to be welded together simultaneously, while only the two electrodes are directly energized, and the short-circuit conductor only indirectly. The short-circuit conductor ensures an electrical coupling or connection between the electrodes with very low electrical resistance, enabling optimal current flow. The short-circuit conductor bridges the middle component, protecting its essential parts from the high current during contact welding. This prevents damage to the component.This is advantageous, especially when the component has a relatively high electrical resistance. Furthermore, an optimal welding process with maximum power for both welding zones or weld seams is ensured because losses via the short-circuit conductor are low. The individual electrodes and the short-circuit conductor are either single-piece or multi-piece and independent of each other.

[0008] Furthermore, the object of the invention is achieved by producing the first and second welds using a contact welding device, and by providing the housing shell with a radially extending deformation V1, V2 at its end in a region e1 of the first weld and in a region e2 of the second weld. The deformation V1, V2 points radially outwards or inwards with respect to the cylinder's central axis. It is also advantageous if a contact welding device as described is used to produce the first and second welds. The radial deformation of the edge is based on a relative movement between the partially wedge-shaped components to be joined in the welding zone. This relative movement has both an axial and a radial component. The latter leads to the aforementioned radial deformation.Overall, this relative movement, together with the applied force, leads to an optimal material bond during the welding process.

[0009] Other advantages of contact welding an exhaust system as described, particularly compared to other welding processes, include very short cycle times of 2 to 3 seconds with a welding time of less than 30 milliseconds. Furthermore, only small contact areas are required, thus saving material. No additional material, especially no additional filler material or gas, is needed for the welding process. Contact welding also allows relatively thin materials to be welded together, resulting in material and weight savings, particularly for exhaust systems. Furthermore, the highest level of component cleanliness is guaranteed, which is also advantageous with regard to maintenance intervals. In addition, the heat input into the components during the welding process is relatively low, thus minimizing thermal deformation. The contact welding process requires a relatively low overall energy input.Contact welding largely avoids the formation of coarse grains in the material structure, which is particularly advantageous for durability when welding ferritic materials.

[0010] Furthermore, the problem is solved by the method comprising the following steps: a) positioning a first component at the first electrode; b) positioning a second component at the first component; c) positioning a short-circuit conductor at the second component; d) positioning a third component at the second component; e) positioning a second electrode at the third component; f) applying a force F between the first electrode and the short-circuit conductor and a force F between the second electrode and the short-circuit conductor, whereby for this purpose the first electrode and the short-circuit conductor can be actively moved relative to each other and / or the second electrode and the short-circuit conductor can be actively moved relative to each other;g) Applying a voltage and generating a current pulse between the first electrode and the second electrode, wherein the first electrode and the short-circuit conductor are moved relative to each other, and the second electrode and the short-circuit conductor are moved relative to each other, in order to compensate for the deformation of the components associated with the current pulse and the force, or to ensure the setting movement; h) Removing the workpiece; wherein steps a) to e) are alternatively carried out in a different order.

[0011] The process possesses the advantages already discussed. A further advantage of this method is the simple setup of the welding assembly, including the components to be welded, because these elements can be stacked on top of each other. The first electrode can be fixed in place, and the first component is then placed on top. Next, the second component is placed on top, and then the short-circuiting conductor is connected to the second component, only needing to be secured against slipping or falling over. Then, the third component is placed on top of the second component, and finally, the second electrode is attached. Gravity alone ensures a stable setup. One advantage of this is that, for the welding process, an increased force F only needs to be applied to one electrode, i.e., the second electrode, while the short-circuiting conductor only needs to be guided, and the other electrode, i.e., the first electrode, remains fixed.If the uppermost electrode is heavy enough, its weight is sufficient. Therefore, only one of the electrodes needs to be actively moved, and the short-circuit conductor only needs to be mounted in a way that allows it to be tracked. The force F is aligned parallel to the directions of movement R13 and R23.

[0012] It can also be advantageous if the direction of movement R13 is parallel to the direction of movement R23, or if the directions of movement R13 and R23 form an angle greater than 0°. If the directions of movement R13 and R23 are parallel, they are either opposite or the same. The directions of movement R13 and R23 result from the geometry of the components and the geometry of the contact welding device.

[0013] Furthermore, it may be advantageous if the first contact surface has at least one 1a zone with a 1a normal vector, and if the third contact surface has a 3a zone with a 3a normal vector, and if the second contact surface has at least one 2a zone with a 2a normal vector, wherein the angle α between the 1a normal vector and the 3a normal vector is between 130° and 170°, or between 145° and 155°, or is 150°, and / or if the angle β between the 2a normal vector and the 3a normal vector and / or the 3b normal vector is between 130° and 170°, or between 145° and 155°, or is 150°. Advantageously, angle α is equal to angle β, with a tolerance of 5° being most advantageously allowed with respect to the preceding condition. However, both angles α and β can also be formed independently of each other.

[0014] When axial forces are transmitted to the components to be welded via the electrodes or the short-circuit conductor, these generate a radial force component due to the angles α and β. The radial direction refers to the central axis of the short-circuit electrode. For the following discussion, it is assumed that the directions of movement R13 and R23 run parallel to the cylinder's central axis, but this is by no means mandatory. The radial force component can be controlled by means of the angles α and β, thereby achieving optimal contact between the two components. Furthermore, contact is optimized because the radial component of the force deforms the component, thereby increasing its bearing force on the corresponding contact surface of the short-circuit electrode. If, on the other hand, the corresponding angle is smaller than the stressed area, the radial force is reduced, and the welding process is less efficient.The number of zones is arbitrary. With a large number of zones, the shape approaches a circle.

[0015] It can also be advantageous if the first contact surface has a second 1b_zone with a 1b_normal vector and if the second contact surface has a second 2b_zone with a 2b_normal vector, wherein the 1b_normal vector points in the direction of movement R13 and / or the 2b_normal vector points in the direction of movement R23. By forming various zones, it is possible to further optimize the contact between the corresponding components and the contact surface, especially when the geometry of the individual electrodes and / or the short-circuit conductor is adapted to the components. The zone variant described here is particularly suitable for welding the exhaust device according to the invention.

[0016] Advantageously, the short-circuit conductor can be designed as a cylinder with a central axis, wherein the cylinder is divisible in the circumferential direction U into a first cylinder segment and at least one second cylinder segment, each cylinder segment having two connecting surfaces where contact can be made. Advantageously, the first contact surface and / or the second contact surface are annular. Furthermore, it is advantageous if the direction of movement R13 and / or the direction of movement R23 are parallel to the central axis of the cylinder. Since the cylinder consists of divisible cylinder segments, it is possible to wrap them around a component and thus accommodate a component within the closed cylinder.Since the cylinder segments are contactable, the entire cylinder can be traversed by current, thus minimizing the resistance of the short-circuit electrode, even in the transition between the two segments.

[0017] Of particular importance for the present invention is the fact that the short-circuit conductor has a 3a zone and at least one 3b zone, wherein the 3a zone and the 3b zone can be simultaneously applied to a single component. The 3a zone is parallel or coaxial to the 3b zone. A 3b normal vector is defined on the 3b zone, which in this case is parallel to the 3a normal vector. However, it is also possible for the 3b normal vector to be independent of the 3a normal vector, with both vectors then pointing in opposite directions. The ratio of the two vectors 3a and 3b can also vary around the circumference.

[0018] In connection with the design and arrangement according to the invention, it can be advantageous if the 3a_zone and the 3b_zone are provided at different ends of the short-circuit conductor with a distance a3 from each other, relative to the cylinder's central axis. This ensures that the short-circuit conductor contributes to the short circuit along its entire length. This results in extensive protection of the component and a space-saving design of the contact welding device.

[0019] It can also be advantageous if the electrical resistance of the individual electrodes and the short-circuit conductor differs by a maximum factor of 1.3 to 2. However, this factor can also be 1 to 10, or approximately 2 to 8, or even 3 to 5. It can also be advantageous if the first electrode is identical in construction to the second electrode, or if at least one of the electrodes and the short-circuit conductor are made of the same material. Preferably, both electrodes are made of the same material. This is crucial because the material determines the magnitude of the electrical resistance.

[0020] Furthermore, it can be advantageous if the first housing cover has a first opening and / or the second housing cover has a second opening. The opening allows, in particular, the routing of an exhaust pipe through the exhaust device. This is accompanied by an annular design of the respective electrodes.

[0021] Finally, it can be advantageous if, in process step c), at least two cylindrical segments of the short-circuit conductor are positioned on the second component, with the cylindrical segments and the second component being in contact with each other. If the second component rests on the first component, a simple, sequential assembly of the individual segments around the component is possible.

[0022] It can also be advantageous if, in process step f), the contact between the short-circuit conductor and the second component is optimized by applying a normal force FN with a radial component RF between the first electrode and the short-circuit conductor, as well as between the second electrode and the short-circuit conductor. The normal force FN runs parallel to a 1a normal vector or a 2a normal vector and results from the force F.

[0023] Optimized contact between the component and the electrode results in low heat generation within the component and thus low energy and voltage loss at the contact. The force F is optimized by a radial component RF of a force FN parallel to the respective normal vectors 1a, 2a of the respective zones 1a, 2a.

[0024] Further advantages and details of the invention are explained in the claims and the description and illustrated in the figures. These show: Fig. 1 a cross-section of the contact welding device; Fig. 2a a detailed section from Fig. 1; Fig. 2b a further detail excerpt from Fig. 1; Fig. 3 a schematic diagram of a cylindrical short-circuit conductor; Fig. 4a an exhaust device before the contact welding process; Fig. 4b an exhaust device after the contact welding process; Fig. 5 a schematic representation of a further embodiment; Fig. 6 a schematic representation of an alternative embodiment.

[0025] A contact welding device 10 after Fig. 1 includes a first electrode 1, a second electrode 2 and a short-circuit conductor 3 Using the contact welding device 1 will an exhaust device 5 , encompassing a first case cover 5.1 , a casing 5.2 and a second case cover 5.3 , welded.

[0026] The first case cover 5.1 shows a draft 5.6 and a ring-shaped bend 5.1a up. The bend 5.1a divides the first case cover 5.1 into two areas. The inner area lies between the passage. 5.6 and the chamfer 5.1aThe inner area is flat and ring-shaped. The chamfer 5.1a is conical-ring shaped. The housing shell 5.2 is cylindrical in shape. The second housing cover 5.3 also has a draft 5.7 and a ring-shaped bend 5.3a on.

[0027] The casing 5.2 It is on the bevel. 5.1a of the case cover 5.1 The inner diameter of the bend. 5.1a is smaller than the inner diameter of the casing 5.2 .

[0028] The second case cover 5.3 It lies in a corresponding manner with the chamfer. 5.3a on the casing 5.2 The diameter of the bend. 5.3a is also smaller than the inner diameter of the housing shell 5.2. The first housing cover 5.1 is of the same shape as the second case cover 5.3 The sheet metal thickness of the first housing cover 5.1, of the second case cover 5.3 and the casing 5.2 is the same.

[0029] The first electrode 1 is ring-shaped and has a central passage 1.6 on, which is coaxial to the passage 5.6 lies. The first electrode 1 Furthermore, it has a first contact surface 1.1 , which are the case lid 5.1 after it has formed. The first contact surface 1.1 It has a 1a_Zone 1.2 and a 1b_Zone 1.4. Both zones 1.2 , 1.4 They are angled relative to each other. The angle corresponds to the bending. 5.1a The first contact surface 1.1 is therefore congruent with a surface of the first housing cover 5.1 . About the first contact surface 1.1 are the first electrode 1 and the case lid 5.1 brought to the facility.

[0030] The second electrode as well 2is ring-shaped and has a central passage 2.6, which is coaxial to a passage 5.7 is arranged. Furthermore, the second electrode has 2 a second contact surface 2.1 The second contact surface 2.1 has a 2a_zone 2.2 and a 2b_zone 2.4. Both zones 2.2 , 2.4 They are angled relative to each other. The angle corresponds to the bend 5.3a. The second contact surface 2.1 is congruent with a surface of the second housing cover 5.3 . At the second contact surface 2.1 are the second electrode 2 and the second component 5.3 brought to the facility.

[0031] The short-circuit conductor 3 takes the casing 5.2 up. The short-circuit conductor 3 has a third contact surface 3.1 which is in turn divided into an annular 3a_zone 3.2 and an annular 3b_zone 3.4. Both zones 3.2 ,3.4 have a distance a3 to each other. The third contact surface 3.1 and thus the 3a_Zone 3.2 and the 3b_Zone 3.4 are attached to the housing shell 5.2 brought to the plant. Furthermore, the short-circuit conductor indicates 3 a cylinder central axis 3.5 on. Coaxial to this cylinder's central axis 3.5 The passage 1.6 and the draft 2.6 .

[0032] The zones 3.4 , 3.2 are each at the end of the short-circuit conductor 3 planned. The zones 3.2 , 3.4 point radially inwards towards the housing shell 5.2 protrude and run coaxially to the cylinder's central axis 3.5 Zone 3a 3.2 is perpendicular to Zone 1b 1.4. Zone 3b 3.4 is perpendicular to Zone 2b 2.4.

[0033] The first electrode 1 and the short-circuit conductor 3 are relative to each other in one direction of movement R13movable. The second electrode 2 and the short-circuit conductor 3 are relative to each other in one direction of movement R23 movable. To generate the movements, it is sufficient if, for example, the second electrode 2 is actively moved and the short-circuit conductor 3 with movement, as long as the first electrode 1 is fixed. The directions of movement R13 and R23 run parallel to the cylinder's central axis 3.5 , oriented in opposite directions.

[0034] According to Fig. 2a shows the third contact surface 3.1 of the short-circuit conductor 3 a 3a_normal vector 3.3 or a 3b_normal vector 3.9, each perpendicular to the directions of motion R13 , R23 runs. Furthermore, the 2a_zone 2.2 has a 2a_normal vector 2.3. After Fig. 1 to Fig. 2b shows the third contact surface 3.1a 3a_Zone 3.2 and a 3b_Zone 3.4, where the respective zone 3.2 , 3.4 A 3a_normal vector 3.3 or a 3b_normal vector 3.9 is assigned. On the 2b_zone 2.4 there is a 2b_normal vector 2.5, which runs parallel and in the direction of motion R23. The 2a zone 2.2 or the second electrode 2 and the third contact surface 3.1 or the short-circuit conductor 3 show a distance a2 which is reduced during the welding process.

[0035] The 3b_normal vector 3.9 and the 2a_normal vector 2.3 close an angle. β one. The angle β is 135°. Zone 2a and Zone 2.4 are at an angle (270° - ) to each other. β ) angled.

[0036] A force F runs in the direction and parallel to the direction of movement R23 The power F is the cause of normal forces FN , which run parallel to the 2a_normal vector 2.3. This normal force FN has a radial component RF , the magnitude of which depends on the angle β It depends. The larger the angle β, the larger the radial component. RF .

[0037] According to Fig. 2b indicates the 1a_zone 1.2 of the first contact surface 1.1 a 1a_normal vector 1.3. The third contact surface 3.1 , in particular the 3a_zone 3.2, has a 3a_normal vector 3.3. The first electrode 1 It still has the 1a_zone 1.4, on which a 1a_normal vector 1.5 is located, which is parallel and aligned with the direction of motion. R13 runs between zone 1a and 1.2, or the first electrode. 1 and the third contact surface 3.1 or the short-circuit conductor 3 there is a gap a1 , which is also reduced during the welding process.

[0038] The 1a_normal vector 1.3 and the 3a_normal vector 3.3 close an angle. α one. The angle α has 135°. Therefore, the angle corresponds to α at the angle β. The 1a_Zone 1.2 and the 1b_Zone 1.4 are angled relative to each other at an angle (270° - α).

[0039] The power F runs parallel and in the direction of movement R23 It results in the normal forces. FN , which run parallel to the 1a_normal vector 1.3. This normal force FN has a radial component RF , the magnitude of which depends on the angle α depends α The larger the radial component, the greater the radial component. RF .

[0040] The short-circuit conductor 3 is according to Fig. 3 a ring cylinder. In the embodiment shown, the short-circuit conductor has 3 a first cylinder segment 3.6 and a second cylinder segment 3.7on, which in the circumferential direction U against each other at connecting surfaces 3.8 are contacted. The short-circuit conductor 3 has a cylinder center axis 3.5 The connecting surfaces 3.8 run in an axial direction to the cylinder's central axis 3.5 .

[0041] According to the exploded view Fig. 4a is the exhaust device 5 Not yet welded. The relative position between the two housing covers. 5.1 , 5.3 and the casing 5.2 are similar to those in Fig. 1 shown. In Fig. 4b is the exhaust device 5 The image shows the weld seam after the welding process. The two enlarged sections show a weld seam. 5.5 between the second case cover 5.3 and the casing 5.2 , as well as a weld seam 5.4 between the first case cover 5.1 and the casing 5.2provided. After the welding process, the housing shell in particular shows 5.2 in an area e1 the weld 5.4 a deformation V1 and in an area e2 the weld 5.5 a deformation V2 The deformations V1 , V2 are due to the radial force RF and point outwards in a radial direction. The deformations V1 , V2 They occur during the welding process when the housing covers 5.1 , 5.3 through the electrodes 1 , 2 against the edge of the casing 5.2 They are pressed down. This is due, in addition to the contact force, to the wedge effect of the conical ring-shaped bend. 5.1a , 5.3a of the lid edge.

[0042] According to Fig. 5 and Fig. 6 are two contact welding devices 10 described with a different electrode architecture1 , 2 and the short-circuit conductor 3 . As a result, after Fig. 5 the direction of movement R13 and direction of movement R23 parallel and aligned. After Fig. The directions of movement are 6 R13 , R23 at right angles to each other. According to an exemplary embodiment as follows. Fig. 5 indicates the third contact surface 3.1 of the short-circuit conductor 3 no zones. In contrast, the short-circuit conductor has 3 according to the exemplary embodiment Fig. 6 a 3a_Zone 3.2 and also a 3b_Zone 3.4. The components 3.1 , 3.2 , 3.3 each at the welding points S welded together. Reference symbol list 1 first electrode 1.1 first contact surface 1.2 1a_Zone 1.3 1a_Normal vector 1.4 1b_Zone 1.5 1b_Normal vector 1.6 Draft 2 second electrode 2.1 second contact surface 2.2 2a_Zone 2.3 2a_Normal vector 2.4 2b_Zone 2.5 2b_Normal vector 2.6 Draft 3 short-circuit conductors 3.1 third contact surface 3.2 3a_Zone 3.3 3a_Normal vector 3.4 3b_Zone 3.5 Cylinder center axis 3.6 first cylinder segment 3.7 second cylinder segment 3.8 Connection surface 3.9 3b_Normal vector 5 workpiece, exhaust device 5.1 First component, first housing cover 5.1a Bending 5.2 Second component, housing shell 5.3 Third component, second housing cover 5.3a Bending 5.4 first weld 5.5 second weld 5.6 Draft 5.7 Draft 10 Contact welding device α angle β angle a1 distance a2 distance a3 distance e1 area of ​​the first weld e2 area of ​​the second weld F force FN Normal force R13 Direction of movement R23 Direction of movement RF radial component S weld point U circumferential direction V1, V2 deformation QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 6791051 B2

[0004] US 7476824 B4

[0005]

Claims

[1] Contact welding device (10) for simultaneously welding at least three components (5.1, 5.2, 5.3) together by means of a current pulse, comprising a first electrode (1) with a first contact surface (1.1) for the attachment of the first component (5.1) and a second electrode (2) with a second contact surface (2.1) for the attachment of the second component (5.2), wherein the first electrode (1) is separated from the second electrode (2) and the first electrode (1) can be configured as an anode or cathode and the second electrode (2) can be configured as an anode or cathode, characterized by, that a short-circuit conductor (3) with at least a third contact surface (3.1) is provided for the system for at least the third component (5.3), wherein a direction of movement R13 is provided in which the first electrode (1) is movable relative to the short-circuit conductor (3), and a direction of movement R23 is provided in which the second electrode (2) is movable relative to the short-circuit conductor (3), wherein a distance a1 between the first contact surface (1.1) and the third contact surface (3.1) can be reduced via the movement in the direction of movement R13, and a distance a2 between the second contact surface (2.1) and the short-circuit conductor (3) can be reduced via the movement in the direction of movement R23. [2] Contact welding device (10) according to claim 1, characterized by that the direction of movement R13 is aligned parallel to the direction of movement R23 or that the direction of movement R13 is at least partially directed opposite to the direction of movement R23. [3] Contact welding device (10) according to claim 1 or 2, characterized by , that the first contact surface (1.1) has at least one 1a_zone (1.2) with a 1a_normal vector (1.3) and that the third contact surface (3.1) has a 3a_zone (3.2) with a 3a_normal vector (3.3) and that the second contact surface (2.1) has at least one 2a_zone (2.2) with a 2a_normal vector (2.3), wherein an angle α between the 1a_normal vector (1.3) and the 3a_normal vector (3.3) is between 130° and 170° or between 145° and 155° or 150°, and / or that an angle β between the 2a_normal vector (2.3) and the 3a_normal vector (3.3) is between 130° and 170° or between 145° and 155° or 150°. [4] Contact welding device (10) according to claim 3, characterized by, that the first contact surface (1.1) has a 1b_zone (1.4) with a 1b_normal vector (1.5) and that the second contact surface (2.1) has a 2b_zone (2.4) with a 2b_normal vector (2.5), where the 1b_normal vector (1.5) points in the direction of the direction of motion R13 and / or the 2b_normal vector (2.5) points in the direction of the direction of motion R23. [5] Contact welding device (10) according to any one of the preceding claims, characterized by , that the short-circuit conductor (3) is designed as a cylinder with a cylinder central axis (3.5), wherein the cylinder is divisible in the circumferential direction U into a first cylinder segment (3.6) and at least into a second cylinder segment (3.7), wherein the cylinder segments (3.6, 3.7) each have two connecting surfaces (3.8) at which the cylinder segments (3.6, 3.7) can be contacted. [6] Contact welding device (10) according to any one of the preceding claims, characterized by, that the short-circuit conductor (3) has the 3a_zone (3.2) and at least one 3b_zone (3.4), wherein the 3a_zone (3.2) and the 3b_zone (3.4) can be connected to the third component (5.3) simultaneously. [7] Contact welding device (10) according to claim 6, characterized by , that the 3a_zone (3.2) and the 3b_zone (3.4) are provided at different ends of the short-circuit conductor (3) with a distance a3 to each other with reference to the cylinder central axis (3.5). [8] Contact welding device (10) according to any one of the preceding claims, characterized by , that the electrical resistance of the individual electrodes (1, 2) and the short-circuit conductor (3) differs by a maximum factor of 1.3 to 2. [9] Exhaust device (5) comprising a housing shell (5.2), a first housing cover (5.1) and a second housing cover (5.3), wherein the housing shell (5.2) is materially bonded to the first housing cover (5.1) via a first weld (5.4) and the housing shell (5.2) is materially bonded to the second housing cover (5.3) via a second weld (5.5), characterized by , that the first weld (5.4) and the second weld (5.5) were produced using a contact welding device (10), and that the housing shell (5.2) has a radially directed deformation V1, V2 at its end in a region e1 of the first weld (5.4) and in a region e2 of the second weld (5.5). [10] Exhaust device (5) according to claim 9, characterized by , that the first housing cover (5.1) has a first passage (5.6) and / or the second housing cover (5.2) has a second passage (5.7). [11] Method for welding three components (5.1, 5.2, 5.3) to form a workpiece (5) using a contact welding device (10), the method comprising the following steps: a) Positioning a first component (5.1) at the first electrode (1); b) Positioning a second component (5.2) on the first component (5.1); c) Positioning a short-circuit conductor (3) on the second component (5.2); d) Positioning a third component (5.3) on the second component (5.2); e) Positioning a second electrode (2) on the third component (5.3); f) Applying a force F between the first electrode (1) and the short-circuit conductor (3) and a force F between the second electrode (2) and the short-circuit conductor (3); g) Applying a voltage and generating a current pulse between the first electrode (1) and the second electrode (2), wherein the first electrode (1) and the short-circuit conductor (3) are moved relative to each other and the second electrode (2) and the short-circuit conductor (3) are moved relative to each other in order to compensate for the deformation of the components (5.1, 5.2, 5.3) associated with the current pulse and the force F; h) Removal of the workpiece (5); wherein steps a) to e) are alternatively carried out in a different order. [12] Method for welding three components (5.1, 5.2, 5.3) according to claim 11, characterized by , that in process step c) at least two cylinder segments (3.6, 3.7) of the short-circuit conductor (3) are positioned on the second component (5.2), whereby the cylinder segments (3.6, 3.7) and the second component (5.2) are contacted with each other. [13] Method for welding three components according to claim 11 or 12, characterized by , that in process step f) the contact between the short-circuit conductor (3) and the second component (5.2) is optimized by applying a normal force FN with a radial component RF between the first electrode (1) and the short-circuit conductor (3) as well as between the second electrode (2) and the short-circuit conductor (3).

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