Stabilizer for the chassis of a motor vehicle and method for manufacturing a stabilizer

Abstract

The invention relates to a stabilizer for a chassis of a motor vehicle, comprising a stabilizer tube (2), a coupling element (5) arranged on a first end section (3) with an insertion section (19), a joining section (6) and a connecting means (7) for detachably connecting a connection element (8), wherein a radial gap (21) is formed between the insertion section (19) and the stabilizer tube (2), and wherein the coupling element (5) is connected to the stabilizer tube (2) via a weld connection (30) produced between the joining section (6) and the stabilizer tube (2) by means of capacitor discharge welding or laser welding.

Description

[0001] The invention relates to a stabilizer for the chassis of a motor vehicle and to a method for manufacturing a stabilizer.

[0002] Stabilizers are used, for example, to reduce the roll angle of a motor vehicle or to influence the driving behavior of a motor vehicle, especially its self-steering behavior.

[0003] Such a stabilizer is known, for example, from EP 3 508 361 A1. There, the stabilizer comprises a stabilizer rod and a stabilizer connection that couples the stabilizer rod to a suspension device. For this purpose, the stabilizer connection has a ball stud with a shaft section and a ball section. The shaft section is inserted into and secured in an open end of the stabilizer rod. In one embodiment, a connecting end of the shaft section is provided with a conical surface that is pressed onto the open end of the stabilizer rod and welded to the stabilizer rod. According to another embodiment, a sleeve is press-fitted into the open end of the stabilizer rod and fitted onto the shaft section.

[0004] US Patent 6,533,301 B1 discloses a stabilizer in which an end adapter is welded to the front of one end of the stabilizer tube. The end adapter includes a threaded bore into which a ball joint is screwed.

[0005] A similar stabilizer with a cylindrical insert with internal thread inserted at the end is known from FR 2 761 009 A1.

[0006] From DE10 2019 103 573 A1, which can be considered prior art, a stabilizer arrangement for a motor vehicle chassis is known, comprising a torsion spring with at least one tubular end section and a connecting element that is detachably connected to the torsion spring by means of a clamping arrangement located in the tubular end section. The clamping arrangement has a conical element and an expanding element with two clamping arms and is radially expandable by the conical element. The connecting element is axially clamped by the expanding element and the conical element and has a support section that is axially supported on the tubular end section. The expanding arms of the expanding element are acted upon radially outwards by the conical element and clamped to an inner surface of the tubular end section.

[0007] The invention is based on the objective of providing a dense and robust stabilizer for the chassis of a motor vehicle that is flexible in its application and easy to manufacture.

[0008] According to a first solution, a stabilizer for a motor vehicle chassis is proposed comprising: a stabilizer tube with an end section and a tube axis, and a coupling element with an insertion section, a conical joining section and a connecting means for detachably connecting a connecting element, wherein the coupling element with its insertion section is arranged in the end section of the stabilizer tube, wherein a radial gap is formed between the insertion section and an inner wall of the stabilizer tube, and wherein the coupling element is joined to the stabilizer tube via a weld connection produced by means of capacitor discharge welding between the conical joining section and the stabilizer tube.

[0009] According to an alternative second solution, a stabilizer for a motor vehicle chassis is proposed comprising: a stabilizer tube with an end section and a tube axis, a coupling element with an insertion section, a flange-shaped joining section and a connecting means for detachably connecting a connecting element, wherein the coupling element with its insertion section is arranged in the end section of the stabilizer tube, wherein a radial gap is formed between the insertion section and an inner wall of the stabilizer tube, and the flange-shaped joining section has a larger outer diameter than the end section of the stabilizer tube, wherein the coupling element is joined to the stabilizer tube via an axial weld connection produced by laser welding between the flange-shaped joining section and an end face of the stabilizer tube.

[0010] The coupling element's joining section allows it to be connected to stabilizer tubes of varying diameters in both solutions. This enables the stabilizer to be flexibly adapted to the requirements of different vehicles. By connecting the coupling element to the stabilizer tube using capacitor discharge welding or laser welding, the heat-stressed joining zone in the weld area is reduced, thereby minimizing material-weakening structural changes in the stabilizer tube. Furthermore, the weld between the conical or flange-shaped joining section of the coupling element and the stabilizer tube ensures that the end section of the stabilizer tube is sealed against liquids and gases. Capacitor discharge welding enables a very stable welding process because the capacitor decouples the welding process from the power grid.Laser welding allows for the creation of a precise and fast welded joint.

[0011] The coupling element is arranged on an end face of the stabilizer tube. According to the first solution, the conical joining section of the coupling element is connected, in particular, to an inner edge of the stabilizer tube, and according to the second solution, the flange-shaped joining section of the coupling element is connected, in particular, to an end face of the stabilizer tube. In the second solution, the welded joint is preferably formed by a weld seam circumferentially around the longitudinal axis of the coupling element. The laser welding is performed in the axial direction; that is, the laser beam shines axially through the flange section into the end face of the tube, so that the end face of the tube fuses with the underside of the flange section and is metallurgically bonded. The laser beam is guided in an annular pattern in overlap with the end face, so that a circumferentially tight weld joint is produced.Preferably, the weld seam is viewed axially from the pipe end or in cross-section through the end section, and is arranged radially outside a central annular line of the pipe or its end section. The weld seam can have a diameter of less than 0.75 mm when laser welding.

[0012] The joining section has a radial height or extent in the radial direction to the longitudinal axis of the coupling element, which can be greater than twice and / or less than five times the wall thickness of the stabilizer tube. In the first case, the radial height can be defined as the distance between the smallest and largest radii of the conical connecting section, and in the second case, as the distance between the outer surface of the insertion section and the outer surface of the flanged section. The radial height can be designed depending on the required thread size of the internal thread. For example, with an internal thread size of M8, the joining section can have a radial height of at least 3 mm and / or up to 6 mm, particularly between 4 and 5 mm. With an internal thread size of M13, the joining section can, for example, have a radial height of at least 7 mm and / or up to 10 mm, particularly between 8 and 9 mm.The wall thickness of the stabilizer tube describes the distance between an inner surface of the inner wall and an outer surface of an outer wall of the stabilizer tube. It can be, for example, a minimum of 2 mm and / or a maximum of 7 mm, without being limited to these values.

[0013] The stabilizer tube is a cylindrical component with a cross-section, for example elliptical or circular, extending longitudinally between a first end section and a second end section. Preferably, the stabilizer tube is bent at one or more bends. For example, the stabilizer tube has two bends.

[0014] The coupling element is designed for the detachable connection of the stabilizer tube to the connecting element and can also be referred to as a connecting or adapter element. The connecting element can, for example, be a ball stud of a connecting rod. Preferably, the coupling element is arranged at least partially on or within the first end section of the stabilizer tube.

[0015] The connecting element is formed on or preferably within the coupling element. Preferably, the connecting element is designed such that the connecting element can be detachably connected to the coupling element. The connecting element and the coupling element are preferably connectable to each other via force-fit and / or form-fit connecting elements.

[0016] The coupling element is connected to the stabilizer tube via a weld, which is recognizable by a weld seam. The weld between the conical or flange-shaped joining section of the coupling element and the stabilizer tube is located in the area of ​​the first end section of the stabilizer tube.

[0017] The welded connection between the stabilizer tube and the coupling element preferably ensures a tightness that reaches 2 bar internal pressure and, after 5 minutes, is still at least 0.75 times the maximum applied pressure.

[0018] The stabilizer tube extends from a first end face located at the first end section to a second end face located at the second end section. The end face of the stabilizer tube defines a terminal cross-section of the stabilizer tube. An end section of the stabilizer tube is understood to be, in particular, a straight section extending from an end face in the longitudinal direction of the stabilizer tube. For example, the end section can extend from the first end face over a length of at least 20 mm, 40 mm, 50 mm, or more. The inner edge of the stabilizer tube can be an edge of the first end face adjacent to an interior space of the stabilizer tube. The end-face arrangement of the coupling element on the stabilizer tube eliminates the need for machining the end section of the stabilizer tube, such as pressing the end section together.This makes the stabilizer particularly easy to manufacture.

[0019] According to one possible embodiment, the coupling element can have a connection surface projecting axially beyond the end face of the stabilizer tube to provide axial support. The connection surface of the coupling element is arranged at a distance from the first end face of the stabilizer tube. Preferably, the connection surface of the coupling element is arranged parallel to the first end face of the stabilizer tube or the welded joint. The axial direction of the stabilizer tube refers in particular to the longitudinal direction of the stabilizer tube, which, at possible bending points, follows the bending direction of the cross-section of the stabilizer tube.

[0020] The contact area of ​​the coupling element can be larger than the cross-sectional area of ​​the stabilizer tube, i.e., the area of ​​the cross-section of the stabilizer tube, and / or the end face of the stabilizer tube. For example, the contact area of ​​the coupling element can be larger than 1.5 times, and in particular larger than 2 times, the cross-sectional area of ​​the stabilizer tube. The stabilizer tube can have a constant cross-sectional area along its length, although designs with variable wall thickness along its length are also possible.

[0021] The diameter and wall thickness of the stabilizer tube can be selected according to the forces to be transmitted. For example, a stabilizer tube can have an inner diameter of at least 14 mm and / or up to 40 mm. The wall thickness of the stabilizer tube can be, for example, between 2 mm and 7 mm. The cross-sectional area of ​​the stabilizer tube is formed, in particular, as an annular area between an outer and an inner contour.

[0022] Because the coupling element has a connection surface for the connecting element located at a distance from the end face, and because the connection surface is preferably larger than the cross-sectional area and / or the end face of the stabilizer tube, high clamping forces can be supported in the contact between the connecting element and the coupling element. This results in a particularly high strength and robust connection between the stabilizer and the connecting element.

[0023] The geometry of the coupling element is also determined, in particular, by the forces to be transmitted. The connection surface of the adapter is preferably annular and dimensioned to reliably support the clamping forces acting on the connection element. For example, the connection surface for a coupling element designed for lower forces may have an inner diameter of at least 8 mm and / or an outer diameter of at least 20 mm. An adapter element designed for higher forces may have a connection surface with an inner diameter of, for example, at least 14 mm and / or an outer diameter of at least 60 mm.

[0024] Following further development, the connecting element of the coupling component can be formed as an internal thread, particularly with a thread size of M8 to M14, and engage with an external thread of the connecting element. The external thread of the connecting element is formed, for example, on a stud section of the connecting element. The connecting element can be designed as a ball stud. The external thread has a thread size corresponding to the size of the internal thread.

[0025] The shape of the coupling element, i.e., its length and diameter, can be designed depending on the thread size.

[0026] According to one embodiment, the length of the coupling element can be greater than the diameter of the stabilizer tube, particularly its outer diameter. The length of the coupling element is defined as the axial distance between the connection surface and a base surface of the coupling element. The connection surface and the base surface of the coupling element are, for example, formed as end faces. The thread size of the internal and external threads is preferably designed according to the specific load case. Different load cases differ, for example, in the forces transmitted from the connection element to the stabilizer tube via the coupling element.

[0027] For a thread with a thread size of M8, the coupling element can, for example, have a length of at least 20 mm, in particular a length between 21 and 25 mm. Furthermore, for a thread with a thread size of M14, a coupling element can, for example, have a length of at least 35 mm, in particular a length between 36 and 40 mm. By using an internal thread as the connecting element, a simple and secure connection between the connecting element and the coupling element can be achieved.

[0028] Because the detachable threaded connection and the coupling element are designed according to the load case, the stabilizer is even more versatile. A coupling element whose length is greater than the diameter of the stabilizer tube, particularly the outer diameter of the stabilizer tube's cross-sectional area, enables a threaded connection between the coupling element and the connecting element with high reliability and strength.

[0029] The coupling element has an insertion section extending longitudinally from the conical or flange-shaped joining section and arranged in the end section of the stabilizer tube. The insertion section can have at least a partially cylindrical shape and can therefore also be referred to as a cylindrical section. At one end, facing away from the joining section, the insertion section is preferably closed, meaning that the coupling element has a bottom surface without openings at the end of the insertion section. The closed structure of the insertion section seals the interior of the stabilizer tube from the outside. The insertion section is preferably arranged coaxially with the tube axis within the stabilizer tube.

[0030] A radial gap is preferably formed between the insertion section of the coupling element and the inner wall of the stabilizer tube. Pressing the two components together is not intended. The insertion section preferably has a circumferential surface arranged between the base surface and the joining section. The radial gap is preferably designed such that the circumferential surface of the insertion section does not contact the inner wall of the stabilizer tube. The radial gap can have a substantially constant distance to the inner wall of the stabilizer tube in the circumferential direction relative to the longitudinal axis of the coupling element. For example, the radial gap can have a length of 0.1 to 0.5 mm. The insertion section enables a simple and reliable design of the coupling element depending on the thread size and also ensures that large forces can be supported by the robust coupling element.The radial gap between the insertion section of the coupling element and the inner wall of the stabilizer tube ensures a force flow via the welded connection between the inner edge or end face of the stabilizer tube on the one hand and the conical or flange-shaped joining section on the other.

[0031] The stability and strength of the stabilizer are ensured by the robust coupling element. This allows for a reduction in the wall thickness of the stabilizer tube, thereby lowering manufacturing costs. Furthermore, the advantageous ratio between the wall thickness of the stabilizer tube and the radial height of the conical or flange-shaped joining section allows the coupling element to be used even more flexibly with a wide variety of stabilizer tubes of different diameters.

[0032] According to one embodiment, the stabilizer tube and the coupling element can be made of different materials, thereby reducing the manufacturing costs of the stabilizer and allowing it to be adapted even more flexibly to the respective load case. The different materials are selected for their good weldability. The stabilizer tube, for example, is made of a low-alloy case-hardening steel, such as 26MnB5 or 34MnB5. The coupling element is made, for example, of a structural steel.

[0033] A further coupling element with a conical joining section can be arranged on or in the second end section of the stabilizer tube and connected to it via a weld joint created by capacitor discharge welding between the conical joining section and the stabilizer tube. Alternatively, a further coupling element with a flange-shaped joining section can also be arranged on the second end section and connected to it via a weld joint created by laser welding between the flange-shaped joining section and the stabilizer tube. The coupling elements of a stabilizer are preferably identical.

[0034] The problem is further solved by a stabilizer assembly for the chassis of a motor vehicle, consisting of a stabilizer as described above and at least one connecting element detachably connected to the coupling element. The stabilizer can have two connecting elements, each detachably connected to a coupling element. The connecting element can, for example, be a ball stud of a connecting rod. The stabilizer assembly can be connected to the vehicle body by means of one or more clamps.

[0035] The problem is further solved by a method for manufacturing a stabilizer according to one of the above embodiments for a chassis of a motor vehicle comprising the following steps: - Inserting the coupling element into the end section of the stabilizer tube, whereby an annular gap is formed between the insertion section and the stabilizer tube and the joining section comes into contact with the end section, and - Connecting the coupling element to the stabilizer tube via a weld joint created between the joining section and the stabilizer tube by means of capacitor discharge welding or laser beam welding, and - Bending of the stabilizer tube after guiding the coupling element.

[0036] The stabilizer tube is cut to length before the coupling element is inserted to create the end section. The stabilizer tube can be cut to length by sawing, and deburring can be performed to create a defined edge. Theoretically, the stabilizer tube could also be bent before being connected to the coupling element.

[0037] Preferred embodiments of the invention are explained below with reference to the drawings. The drawings show, in schematic representation: Fig. 1 a perspective view of a stabilizer according to the invention for a chassis of a motor vehicle with a stabilizer tube and two coupling elements in a first embodiment; Fig. 2 a sectional view of a first end section of the stabilizer of Fig. 1; Fig. 3A a perspective view of the coupling element of Fig. 1 and Fig. 2; Fig. 3B a sectional view of the coupling element of Fig. 3A; Fig. 4A a perspective view of a coupling element in a modified design for a stabilizer analogous to Fig. 1 to 3B; Fig. 4B a sectional view of the coupling element of Fig. 4A; Fig. 5 a stabilizer arrangement with the stabilizer of Fig. 1 and Fig. 2 and two connection elements, each connected to a coupling element and Fig. 6 a sectional view of the stabilizer arrangement of Fig. 5 at the first end section of the stabilizer Fig. 7A a perspective view of a stabilizer according to the invention for a chassis of a motor vehicle with stabilizer tube and coupling element in a second embodiment; Fig. 7B an enlarged view of the end section of the stabilizer made of Fig. 7A; Fig. 7C the end section of the stabilizer Fig. 7A in longitudinal section; Fig. 8A the coupling element of the stabilizer made of Fig. 7A in a first perspective view; Fig. 8B the coupling element of the stabilizer made of Fig. 7A in a second perspective view; Fig. 8C the coupling element of the stabilizer made of Fig. 7A in axial view; Fig. 8D the coupling element according to section line 8D-8D from Fig. 8A.

[0038] Fig. Figure 1 shows a schematic perspective view of a stabilizer 1 for the chassis of a motor vehicle in a first embodiment. The stabilizer 1 has a stabilizer tube 2 with a first end section 3 and a second end section 4.

[0039] Furthermore, the stabilizer 1 has a coupling element 5 inserted into the stabilizer tube 2 at the first end section 3 and at the second end section 4. The coupling elements 5 each have a conical joining section 6 and a connecting element 7 for detachable connection to a connecting element 8 (see figure). Fig. 5 and Fig. 6) on.

[0040] The stabilizer tube 2 and the coupling element 5 are, in this case, made of different weldable materials, without being restricted to this. For example, the stabilizer tube 2 can be made of a low-alloy case-hardening steel and the coupling element 5 of a structural steel.

[0041] The coupling elements 5 are, as in Fig. 2 shown, each connected to the stabilizer tube 2 via a weld connection 30 produced by means of capacitor discharge welding between the conical joining section 6 and the stabilizer tube 2.

[0042] The arrangement of the coupling elements 5 on the stabilizer tube 2 is described below by way of example for the coupling element 5 arranged on the first end section 3.

[0043] The stabilizer tube 2 has a first end face 9 located at the first end section 3 and a second end face 10 located at the second end section 4. The coupling element 5 is located at the first end face 9 of the stabilizer tube 2, and the weld 30 connects the conical joining section 6 of the coupling element 5 to an inner edge 11 of the stabilizer tube 2. The inner edge 11 of the stabilizer tube 2 is an edge of the first end face 9 adjacent to an interior space 12 of the stabilizer tube 2.

[0044] The coupling element 5, connected to the stabilizer tube 2, has a connecting surface 13 projecting axially beyond the first end face 9 of the stabilizer tube 2, which can serve as a contact or clamping surface for the connecting element 8. The connecting surface 13 of the coupling element 5 is arranged at a distance from and parallel to the first end face 9 of the stabilizer tube 2. Furthermore, the connecting surface 13 of the coupling element 5 is larger than the cross-sectional area 14 of the stabilizer tube 2. The cross-sectional area of ​​the stabilizer tube 2 is defined as an annular area 14 between an outer contour 16 and an inner contour 15.

[0045] The connection surface 13 of the coupling element 5 can be larger than 1.5 times, and in particular larger than 2 times, the annular surface 14 of the stabilizer tube 2. The annular surface 14 of the stabilizer tube 2 can, for example, have an outer diameter D14 of 10 to 50 mm, and the connection surface 13 can, for example, have a diameter D13 of 15 to 80 mm.

[0046] In Fig. 3A and Fig. Figure 3B shows a first embodiment of the coupling element 5. The connecting element of the coupling element 5 is designed as an internal thread 7, here for example with a thread size of M8 to M14, and can be engaged with a corresponding external thread 17 of the connecting element 8 (see Figure 3B). Fig. 6).

[0047] The shape of the coupling element 5, i.e., its length L and the diameter D13 of the connection surface 13, can be designed depending on the thread size of the internal thread 7. The length L of the coupling element 5 is greater in the direction of a longitudinal axis A5 of the coupling element 5 than the outer diameter D14 of the annular surface 14 of the stabilizer tube 2. The length L of the coupling element 5 describes the axial distance between the connection surface 13 and a bottom surface 18 of the coupling element 5.

[0048] The thread size of the internal thread 7 and the external thread 17 can be designed depending on the specific load case. For example, with an internal thread 7 with a thread size of M8, the coupling element 5 can have a length L of 19 to 30 mm. Furthermore, with an internal thread 7 with a thread size of M14, the coupling element 5 can have a length L of 34 to 45 mm.

[0049] The coupling element 5 has an insertion section 19 extending in the direction of the longitudinal axis A5 of the coupling element 5 from the conical joining section 6 and arranged in the first end section 3 of the stabilizer tube 2. The insertion section 19 is closed at one end facing away from the joining section 6, i.e., at the bottom surface 18. Furthermore, the insertion section 19 is, as shown in Fig. 2 shown, arranged coaxially in the stabilizer tube 2.

[0050] The coupling element 5 and the stabilizer tube 2 are not pressed together. In the radial direction to the longitudinal axis A5 of the coupling element 5, a radial gap 21 is provided between the insertion section 19 of the coupling element 5 and an inner wall 20 of the stabilizer tube 2.

[0051] The insertion section 19 has a lateral surface 22 arranged between the base surface 18 and the conical joining section 6. In the circumferential direction to the longitudinal axis A5 of the coupling element 5, the radial gap 21 has a substantially constant distance to the inner wall 20 of the stabilizer tube 2. For example, the radial gap 21 can have a radial extent LR of 0.1 to 0.5 mm.

[0052] The conical joining section 6 has a radial height 23 with respect to the longitudinal axis A5 of the coupling element 5, which can be two to five times the thickness DW of the wall 24 of the stabilizer tube 2. The radial height 23 is defined as half the distance between the largest diameter DV2 and the smallest diameter DV1 of the conical joining section 6. The thickness DW of the wall 24 of the stabilizer tube 2 describes the distance between the inner wall 20 and an outer wall 25 of the stabilizer tube 2. For example, the wall 24 has a thickness DW of 1 mm to 4 mm, here, for example, less than 2 mm.

[0053] The radial height 23 can be designed depending on the required thread size of the internal thread 7. For example, the conical joining section can have a radial height 23 of 3 to 6 mm for an internal thread 7 with a size of M8, and a radial height 23 of 7 to 10 mm for an internal thread 7 with a size of M13.

[0054] The Fig. 4A and Fig. 4B show a second embodiment of the one described in the Fig. Coupling element 5 shown in 1 to 3b. The same reference numerals are used for identical components or elements. The one shown in the Fig. 4A and Fig. The coupling element 5 shown in 4B differs from the one shown in the Fig. The coupling element shown in 1 to 3B is modified by a different design of the conical joining section 6 and a circumferential recess 27 that reduces the connection surface 13.

[0055] In a method for manufacturing the stabilizer 2, the stabilizer tube 2 is cut to length by sawing before the coupling elements 5 are arranged to create the end sections 3 and 4. No further finishing of the end sections 3 and 4 is required. The coupling elements 5 are then arranged at the end sections 3 and 4 within the stabilizer tube 2. The conical joining sections 6 are each in contact with the inner edge 11 of the stabilizer tube 2. To connect the coupling elements 5 to the stabilizer tube 2, a weld is created at the contact point between the conical joining section 6 and the stabilizer tube 2 by means of capacitor discharge welding. The stabilizer tube 2 is bent only after the coupling elements 5 have been welded to it. Alternatively, the stabilizer tube 2 can be bent before the coupling elements 5 are welded to it.

[0056] In the Fig. 5 and Fig. Figure 6 shows a stabilizer assembly 26 for a motor vehicle chassis, comprising a stabilizer 1 and two detachably connected ball studs 18. The ball studs 18 have an external thread 17 formed on a stud section 28. The external thread 17 has a thread size corresponding to the internal thread 7. The stabilizer 1 is connected to a connecting rod 29 via the ball studs 18. Two connecting clamps 31 are arranged on the stabilizer tube 2.

[0057] The conical joining section 6 of the coupling elements 5 enables the coupling elements 5 to be connected to stabilizer tubes of 2 different diameters D14.

[0058] The Fig. Figures 7A to 8D, which are described together below, show a stabilizer 1 and a coupling element 5 according to the invention, respectively, in a further embodiment. The present embodiment largely corresponds to the embodiment according to the Fig. 1 to 3B, so that abbreviated reference is made to the description above. Identical or corresponding details are marked with the same reference symbols as in the figures above.

[0059] The one in the Fig. Stabilizer 1 shown in Figures 7A to 8D differs from the above versions by a different design of the coupling element 5. As can be seen in particular from the Fig. As can be seen in Figures 8A to 8D, the coupling element 5 has a flange-shaped joining section 6 to which the insertion section 19 axially connects. The coupling element 5 is inserted into the tube with its longitudinal axis A5 coaxial to the tube axis LS, with the flange section coming into contact with the end face of the tube. The flange-shaped joining section 6 has a larger outer diameter DV2 than the end section 3 of the stabilizer tube 2. Furthermore, the insertion section 19 has a smaller outer diameter D19 than the inner diameter Di3 of the end section 3 of the stabilizer tube 2.

[0060] According to the invention, the weld joint 30 is formed by laser welding through a weld seam circumferentially around the pipe axis LS or the longitudinal axis A5 of the coupling element 5. The laser beam is axially aligned and has radial overlap with the end face 9 of the pipe end. In this way, the laser shines axially through the flange section 6 into the end face of the pipe, so that the end face of the pipe fuses with the underside of the flange section and is metallurgically bonded. The welding is carried out circumferentially as an annular closed weld seam 30. As particularly shown in Fig. As can be seen in Figure 7C, the weld seam 30 lies radially outside a central annular line RL3 of the end section 3. The central annular line RL3 is an imaginary line formed midway between the outer and inner circumferential edges of the tube when viewed axially. The weld seam can have a diameter of less than 0.75 mm. Laser welding allows for the efficient production of high-precision welded joints. Laser welding offers the same advantages as capacitor discharge welding. Because the welding is performed on the end face, adaptation to different tube dimensions is ensured via the contact surface of the coupling element 5 or inserts.

[0061] All features described in connection with individual embodiments of the invention can be provided in different combinations for the stabilizer 1 and the stabilizer arrangement 26, as well as the method for manufacturing the stabilizer 1, in order to realize their advantageous effects, even if these have been described for different embodiments. For example, the stabilizer arrangement 26 has coupling elements 5, which are also used for a stabilizer according to Fig. 1 can be used. Or, conversely, the coupling element can also be made from Fig. 1 for a stabilizer according to Fig. 5, Fig. 6 can be used. Reference symbol list 1 stabilizer 2 stabilizer tube 3 first end section 4 second final section 5 coupling element 6 Joining section 7 Fasteners (internal threads) 8 Connection element (ball stud) 9 first front face 10 second front face 11 Inner edge 12 Interior 13 Connection area 14 Cross-sectional area (ring area) 15 Inner contour 16 Outer contour 17 external threads 18 floor area 19 Insert section 20 Interior wall 21 Radial gap 22 Surface area 23 Radial height 24 wall 25 Exterior wall 26 Stabilizer arrangement 27 circumferential groove 28 T-section 29 Stabilizer link 30 welded joints 31 Connection clamp A5 axle D13 Diameter of the connection surface D14 Diameter of the ring surface of the stabilizer tube DV1 smallest diameter of the joining section DV2 largest diameter of the joining section DW Wall thickness L Length of the coupling element LR Radial extent of the radial gap LS longitudinal direction of the stabilizer tube

Claims

[1] Stabilizer for the chassis of a motor vehicle, comprising: a stabilizer tube (2) with an end section (3) and a tube axis (LS), and a coupling element (5) with a plug-in section (19), a conical joining section (6) and a connecting element (7) for detachably connecting a connection element (8), wherein the coupling element (6) with its insertion section (19) is arranged in the end section (3) of the stabilizer tube (2), wherein a radial gap (21) is formed between the insertion section (19) and an inner wall (22) of the stabilizer tube (2), and characterized by , that the coupling element (6) is joined to the stabilizer tube (2) via a weld connection (30) produced by means of capacitor discharge welding between the conical joining section (6) and the stabilizer tube (2). [2] Stabilizer according to claim 1, characterized by, that the conical joining section (6) of the coupling element (5) is connected to an inner edge (11) on an end face (9) of the stabilizer tube (2) by means of the weld connection (30). [3] Stabilizer for the chassis of a motor vehicle, comprising: a stabilizer tube (2) with an end section (3) and a tube axis (LS), a coupling element (5) with a plug-in section (19), a flange-shaped joining section (6) and a connecting element (7) for detachably connecting a connection element (8), wherein the coupling element (6) with its insertion section (19) is arranged in the end section (3) of the stabilizer tube (2), wherein a radial gap (21) is formed between the insertion section (19) and an inner wall (20) of the stabilizer tube (2), and the flange-shaped joining section (6) has a larger outer diameter (DV2) than the end section (3) of the stabilizer tube (2), characterized by , that the coupling element (5) is joined to the stabilizer tube (2) via an axial weld connection (30) produced by laser welding between the flange-shaped joining section (6) and an end face (9) of the stabilizer tube (2). [4] Stabilizer according to claim 3, characterized by , that the welded joint (30) is formed by a weld seam circumferentially around a longitudinal axis (A5) of the coupling element (5), which, viewed in cross-section through the end section (3), is arranged radially outside a mean annular line (RL3) of the end section (3). [5] Stabilizer according to claim 3 or 4, characterized by that the weld has a weld diameter of less than 0.75 mm. [6] Stabiliser according to any one of claims 1 to 5, characterized by, that the coupling element (5) has a connecting surface (13) projecting axially beyond the end of the stabilizer tube (2) in order to axially support the connecting element (8). [7] Stabilizer according to claim 6, characterized by , that the connection area (13) of the coupling element (5) is larger than a cross-sectional area (14) of the stabilizer tube (2). [8] Stabiliser according to any one of claims 1 to 7, characterized by , that the connecting element of the coupling element (5) is formed as an internal thread (7), in particular with a thread size of M8 to M14, and can be engaged with an external thread (17) of the connecting element (8). [9] Stabilizer according to any one of claims 1 to 8, characterized by , that a length (L) of the coupling element (5) in the longitudinal direction is greater than a diameter (D14) of the stabilizer tube (2). [10] Stabiliser according to any one of claims 1 to 9, characterized by, that the insertion section (19) is designed to be closed at an end facing away from the joining section (6). [11] Stabiliser according to any one of claims 1 to 10, characterized by , that the joining section (6) in the radial direction to the longitudinal axis (A5) of the coupling element (5) has a radial height (23) which is greater than 2 times and less than 5 times the wall thickness (DW) of the stabilizer tube (2). [12] Stabilizer according to at least one of claims 1 to 11, characterized by , that the stabilizer tube (2) and the coupling element (5) are made of different materials. [13] Stabilizer according to at least one of claims 1 to 12, characterized by, that a further coupling element (5) with a joining section (6) is arranged at a second end section (4) of the stabilizer tube (2) and is connected to the stabilizer tube (2) via a welded connection (30) created by welding between the joining section (6) and the stabilizer tube (2). [14] Method for manufacturing a stabilizer for a chassis of a motor vehicle according to any one of claims 1 to 13, comprising the steps: - Inserting the coupling element (5) into the end section (3) of the stabilizer tube (2), whereby an annular gap (21) is formed between the insertion section (19) and the stabilizer tube (2) and the joining section (6) comes into contact with the end section (3), - Connecting the coupling element (5) to the stabilizer tube (2) by means of capacitor discharge welding or laser beam welding, whereby a welded joint (30) is created between the joining section (6) of the coupling element (5) and the stabilizer tube (2), and - Bending of the stabilizer tube (2) after joining the coupling element (5) to the stabilizer tube.

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