GB2480519A

GB2480519A - A motor vehicle suspension and a method for the production of a crossbeam thereof

Info

Publication number: GB2480519A
Application number: GB201104429A
Authority: GB
Inventors: Udo Mildner; Lothar Teske
Original assignee: GM Global Technology Operations LLC
Current assignee: GM Global Technology Operations LLC
Priority date: 2010-03-24
Filing date: 2011-03-16
Publication date: 2011-11-23
Anticipated expiration: 2031-03-16
Also published as: GB201104429D0; GB2480519B; DE102010012486A1

Abstract

A motor vehicle suspension is provided having a crossbeam 3 and node elements 6, 7 at each end 4, 5 of the crossbeam 3 and a method for producing a crossbeam 3 is also provided. The node elements 6, 7 fasten the crossbeam 3 to a vehicle frame. The crossbeam 3 is formed from a light metal, such as titanium or aluminum alloy, and has hollow tubular ends 4, 5. The node elements 6, 7 are each located on the hollow tubular ends 4, 5 of the crossbeam 3 using a tube attachment 8 made of steel alloys, light metals, or fiber-reinforced plastics. The external diameter dAof the tube attachment 8 is smaller than internal diameter diof the hollow tubular ends 4, 5 of the crossbeam 3. The hollow tubular ends 4, 5 are fixed by material bonding, such as electromagnetic pulse-welding, onto the tube attachments 8 of the node elements 6, 7 in a limited ring-shaped area.

Description

Suspension of a vehicle and method for the production of a crossbeam thereof The application relates to a suspension of a vehicle having a crossbeam and node elements at the ends of the crossbeam and a method for producing a crossbeam. The node elements fasten the crossbeam to a vehicle frame.

Figure 8 shows, as an example, a rear axle according to the prior art as an assembly of the suspension. Figure 9 shows a crossbeam having node elements at the ends of the crossbeam in a typical construction in detail. This rear axle 30 ac- cording to Figure 8 has a Watt linkage 9 having an upper sus-pension arm 31 and a lower suspension arm 32, which ensure parallel guiding of rear wheels on a crank rod 10 or 11, re-spectively. For this purpose, the suspension arms 31 and 32 are situated spaced apart from one another vertically on a central mount 15, which is fixed in the center of the cross-beam.

The crank rods 10 and 11, which carry the rear wheels, have a first crank arm 33 and a second crank arm 34, which are each fixed on the vehicle frame so they are pivotable via a pivot joint 12 or 13. The two crank arms 33 and 34 are connected to one another via a transverse tubular torsion spring element 14 in the case of a so-called semirigid axle. The Watt lin-kage 9 is linked using its suspension arms 31 and 32 on the free ends 35 and 36 of the crank arms 33 and 34.

The suspension parts of such a rear axle 30 in a typical con- struction have the disadvantage that they contribute a sig-nificant component to the empty vehicle weight because of the heavy plate steel components and tubular steel components as well as diverse cast steel and forged steel parts. The box- shaped structure of the crossbeam 3 made of plate steel hay-ing the central mount 15 for the Watt linkage 9 also provides a contribution to the total weight of the vehicle, which also has a loading effect on the CO2 emission in the case of ye-hides having internal combustion engines.

This heavy plate steel construction of the crossbeam 3 is shown in detail in Figure 9. Components having identical functions as in Figure 8 are identified by identical refer- ence numerals and are not explained separately. The box pro- file of the crossbeam 3 contributes to the fact that in addi-tion to the high weight load, a cost-intensive manufacturing method requiring complex manufacturing is to be provided for a typical suspension.

A method for fixing a tubular transverse component on an arm, in particular for a semirigid axle of a vehicle, is known from US 2004/0148751 Al. The movable arms of the semirigid transverse axle are connected to the tubular transverse corn-ponent as the tubular torsion spring element and at least one of the arms is rigidly fixed on the tubular transverse compo-nent employing an electromagnetic deformation process. The fixing is performed while the transverse component and the at least one arm are in a fixing position to one another and el-ther the tubular transverse component or the arm has at least one metal material.

This known method has the potential that different materials can be connected to one another by material bonding. A disad-vantage of this method, however, is that it does not appear suitable for box-shaped node elements and for box-shaped crossbeams and other parts of a modern suspension.

The object of the application is to exhaust the savings po- tential with respect to costs, weight, and pollutant emis-sions of a vehicle in the area of optimizing components of a suspension of the vehicle and to provide a suspension which is to display a lower contribution to the empty weight of the vehicle and a significant cost reduction during the manufac- turing of the suspension on the example of a structural com-ponent of the suspension.

This object is achieved by the subject matter of independent claims. Advantageous refinements of the application result from the dependent claims.

A suspension of a vehicle having a crossbeam and node ele-ments on the ends of the crossbeam and a method for producing the crossbeam are provided by a first embodiment of the ap- plication. The node elements fasten the crossbeam to a ve-hicle frame. The crossbeam has light metals such as titanium or aluminum alloys having hollow-tubular ends. The node ele-ments are each situated using a tube attachment made of steel alloys, light metals, or fiber-reinforced plastics on the hollow-tubular ends of the crossbeam. External dimensions of the tube attachments are smaller than internal dimensions of the hollow-tubular ends of the crossbeam. The hollow-tubular ends of the crossbeam are fixed by material bonding on the tube attachments of the node elements in a limited ring-shaped area.

Not only is the advantage of providing crossbeams having box-shaped profile, which were heretofore cost-intensive and heavy, in cost-effectively producible components made of tu-bular profiles for the suspension construction of vehicles connected to this novel concept for a suspension of a ve- hicle, but rather the manufacturing times are also to be re-duced cost-effectively with the aid of a high-speed material bonding method, as is known from the above-mentioned publica-tion. Upon the combination of extruded light metal tubes as crossbeam tubes and fiberglass-reinforced plastic node ele-ments for the fixing of the crossbeam on the vehicle body, suspension structures result, which may provide a significant contribution to the improvement of future vehicles both in cost reduction and also in weight reduction.

In a further embodiment of the application, the suspension of a vehicle is equipped with a Watt linkage for the parallel guiding of rear wheels on a crank rod for each rear wheel.

The crank rod is connected via a pivot joint to a rear frame of a vehicle frame. The crank rods carrying rear wheels are transversely connected to one another via a torsion spring element and the Watt linkage is linked to a central mount of the crossbeam.

The ends of the crossbeam have node elements to the rear frame of the vehicle, so that the crossbeam can be removably connected to the rear frame of the vehicle with the aid of the node elements. This crossbeam in turn has crossbeam tubes between the central mount and the node elements and the node elements have tube attachments toward the crossbeam tubes.

The external diameters of these tube attachments are smaller than the internal diameters at the ends of the crossbeam tubes, so that they may be inserted into one another for fix-ing and fixed by material bonding in a limited ring-shaped area.

This embodiment of the application is directed to optimizing the rear axle design of a suspension of a vehicle both with respect to cost and also with respect to weight, a joining method being used which connects different metals and differ-ent materials of the tube attachments and the tubular ends of the crossbeam tubes to one another within seconds and without problems. Therefore, the hollow-tubular ends of the crossbeam tubes are electromagnetically pulse-welded on the tube at-tachments of the node elements and fixed in a ring shape in a limited area.

During this electromagnetic pulse-welding, ring-shaped areas of the hollow-tubular ends and the tube attachments are fixed on one another and materially bonded or welded in that a cur- rent pulse of several thousand amperes flows through the met-al components of the tubular structures to be connected and, because of Lorentz forces, causes the metal tubular ends of the crossbeam tubes to shrink on the tube attachments at sev-eral hundred meters per second and induces cold welding or material bonding of the ring-shaped areas, which strike one another, of the hollow-tubular ends of the crossbeam tubes and tube attachments of the node elements.

Cold welding always occurs if identical or different metal components strike one another. A materially-bonded and loada-ble connection is achieved if at least one of the two welded components is made of metal and therefore permits an eddy current in the material, which triggers the Lorentz forces and fixes the metal material on a stable tube attachment by material bonding through shrinking at the above-specified shrinking speed.

A significant weight savings for suspensions of vehicles can be achieved in that the heavy cast steel components such as node elements are replaced by fiber-reinforced plastics. By using weight-saving carbon fibers over glass fibers in a plastic, the weight of node elements in the suspension con-struction can be reduced further. Other parts such as the crank arms, which have been implemented up to this point by cast steel parts, may also be produced by carbon-fiber- reinforced plastics in a light construction, so that the emp-ty vehicle weight can be significantly reduced in relation to prior vehicles.

These crank arms made of fiber-reinforced plastic or diecast aluminum or diecast titanium can also have attachments, on which the tubular ends of a transversely situated torsion spring element may in turn be shrunk on electromagnetically in the pulse-welding method. Since similar elasticity proper- ties as for extruded steel tubes can be achieved using cor-responding aluminum alloys or titanium alloys, this torsion spring element, which is important for semirigid axles, can also be manufactured cost-effectively in light construction.

Furthermore, it is provided that the tube attachments have an internal reinforcement structure made of crossing reinforce- ment ribs. These reinforcement ribs prevent the tube attach-ment from collapsing when hollow-tubular ends of a crossbeam tube are shrunk on. The internal reinforcement structure en-sures that the tube attachment maintains its shape during electromagnetic pulse-welding, so that cold welding or a formfitting connection is ensured in a ring-shaped area of the tube attachment. Such an internal reinforcement structure has the advantage over a solid material that the tube attach-ment therefore has a lower weight.

An alternative form for the internal reinforcement structure can be formed by reinforcement ribs originating radially from a center of the tube attachment. The reinforcement ribs on-ginating radially from a center of the tube attachment can be distributed uniformly on the internal circumference of the tube attachment and can thus absorb the forces, which are distributed uniformly on the circumference, during shrinking of hollow-tubular ends of crossbeam tubes on the tube attach-ment.

In a further embodiment of the application, the node element has a box-shaped structure, a screw-on point to the vehicle frame being situated on a top side of the box-shaped struc- ture. This screw-on point allows the crossbeam to be remova- bly connected to the vehicle frame. In addition to the screw-on point on the top side of the box-shaped structure, such a box-shaped node element has the tube attachment on a lateral surface, which is situated at an angle to the lateral surface in one embodiment of the application, in order to receive a curved tubular crossbeam. In one embodiment of the applica- tion, stiffening ribs are situated between the lateral sur-face and the tube attachment, which advantageously protect the tube attachment.

The node element can be a diecast aluminum part, a diecast titanium part, or a fiber-reinforced plastic part, whereby the weight of the node element is significantly reduced in relation to node elements made of cast steel. Fiber-reinforced ceramic sintered materials can also be used for the node elements, since they have a lower specific weight than cast steel materials.

An extruded aluminum material, a tubular steel material, or a tubular titanium alloy material is provided for the crossbeam tubes. A cast steel tubular material is only provided if a significant weight savings can be achieved solely by the node elements. Such steel tubes can be seamless extruded steel tubes or can be produced having a weld seam from rolled plate steel.

Since the central mount in the center of the crossbeam is not a tubular construction, but rather is welded together or molded from mounting surfaces, in one embodiment of the ap-plication, the central mount is fixed in the center of the crossbeam using 002 protective gas welding or by MIG solder-ing. If the crossbeam has a continuous, curved, and integral crossbeam tube, the central mount can be permanently fixed in its middle by this welding method. In order to attach corres-ponding welded surfaces and weld seams, such an integral transverse tube structure can be especially prepared for re- ceiving and welding on the mount in the central area by a hy-droforming method. Instead of a continuous transverse tube having a central area shaped by hydroforming for the central mount, the crossbeam can also be assembled from two crossbeam tubes having a connecting part in the central area. For this purpose, the connecting part has tube attachments, on which tubular ends of the crossbeam tubes are fixed by electromag-netic pulse-welding in a ring-shaped limited area. These tube attachments, which protrude on both sides of the connecting part, also have an internal reinforcement structure to ensure that the tubular attachments withstand the stresses of the electromagnetic pulse-welding. In order to implement a more or less deflected crossbeam depending on the construction and structure of the suspension, it is also possible that the crossbeam tubes themselves are welded together from multiple electromagnetically pulse-welded tube parts, which are plugged one inside another, while forming a curve.

In this application, a vehicle is preferably equipped with hollow-tubular structural elements made of light metals such as titanium or aluminum alloys, the hollow-tubular structural elements having node elements made of light metals or fiber-reinforced plastics on their ends. The node elements have tube attachments toward the hollow-tubular structural ele-ments, whose external dimensions are smaller than internal dimensions of the ends of the structural elements. The node elements are used for the purpose of connecting the hollow- tubular structural elements to the vehicle frame of a ve- hicle, the ends of the structural elements being fixed by ma-terial bonding on the tube attachments of the node elements in a limited ring-shaped area.

Since the vehicle has a plurality of hollow-tubular structur- al elements, it is also possible via the above-mentioned com- ponents of a suspension to implement other structural ele-ments of a suspension in light construction, without reducing the vehicle safety. Such structural elements include the crankshaft or the axle shafts of a rigid axle having diffe-rential gearing.

A method for manufacturing a crossbeam, which is composed of multiple parts, of a vehicle has the following method steps.

Firstly, two box-shaped node elements are made of a steel al- loy, a light metal alloy, or a fiber-reinforced plastic hav-ing tube attachments protruding on one side, which have an external diameter for single-sided attachment on two cross-beam tubes. In addition, a box-shaped central connecting part is manufactured from a steel alloy, a light metal alloy, or a fiber-reinforced plastic having tube attachments protruding on two sides for connection of two crossbeam tubes to form a crossbeam and for attaching a central mount for a Watt lin-kage.

In addition, two crossbeam tubes are produced from a steel alloy or a light metal alloy having hollow-tubular ends, which have a larger internal diameter than the external di- ameter of the attachments of the node elements and the cen-tral connecting part. The fixing of a node element and an end of a crossbeam tube are now performed successively within a device for material bonding while orienting the one-sided tube attachment in the hollow-tubular end and while maintain-ing a radial ring gap. When the tubular end of a crossbeam tube and the tube attachment of a node element are fixed in one another in such a way, a materially-bonded connection of the tube attachment to the hollow-tubular end can be per-formed in a limited ring-shaped area.

For this purpose, a current pulse of several thousand amperes is sent through one or more turns, which induce a correspond-ing eddy current through the metal hollow tube end, so that because of Lorentz forces, the tubular end shrinks at several hundred meters per second onto the tube attachment in a li-mited ring-shaped area and forms a cold-welded connection or a materially-bonded connection to the tube attachment.

In the same way, further materially-bonded connections are performed between the second crossbeam tube and a further node element and between the tube attachments of the central connecting part and the remaining hollow-tubular ends of the two crossbeam tubes.

The subject matter of the application will be explained in greater detail hereafter on the basis of the appended fig-ures.

Figure 1 shows a schematic perspective view of a crossbeam of a suspension according to a first embodiment of the application; Figure 2 shows a schematic perspective view of two crossbeam tubes of the suspension according to Figure 1; Figure 3 shows a schematic perspective view of a node ele-ment of the suspension according to Figure 1; Figure 4 shows a schematic perspective view of a connecting part of the crossbeam tubes according to Figure 2; Figure 5 shows a schematic perspective view of a crossbeam of a suspension according to a second embodiment of the application; Figure 6 shows a schematic perspective view of a one-piece crossbeam tube of a crossbeam according to Figure 5; Figure 7 shows a schematic perspective view of a tubular torsion element of a semirigid axis; Figure 8 shows a schematic perspective view of a rear axle of a suspension of a vehicle having a crossbeam and node elements; Figure 9 shows a schematic perspective view of the crossbeam according to Figure 8 in detail.

Figure 1 shows a schematic perspective view of a crossbeam 3 of a suspension 1 according to a first embodiment of the ap-plication. The crossbeam 3 is composed of five parts. Two crossbeam tubes 16 and 17 made of an aluminum or titanium al- 1oy form, together with a connecting part 24, the crossbeam 3, which has node elements 6 and 7 in a box shape 28 on its hollow-tubular ends 5 and the connecting part 24 on hollow- tubular ends 4 of the crossbeam tubes 16 and 17. The connect-ing part 24 and the node elements 6 and 7 can be produced from the same light metals as the crossbeam tubes 16 and 17.

Only the production method is different.

While the crossbeam tubes 16 and 17 can be produced with the aid of an extrusion method, diecasting methods are used for the node elements 6 and 7 and for the connecting part 24. In addition, it is possible that the node elements 6 and 7 and the connecting part 24 are manufactured from a fiber-reinforced plastic to save further weight for the vehicle. At the joining points 40, the two crossbeam tubes 16 and 17 are connected by material bonding to the three connecting ele-ments 6, 7, and 24 to form a crossbeam 3. The middle part 24 carries a central mount 15 for a Watt linkage and the node elements 6 and 7 allow the attachment of the crossbeam 3 to a frame of the vehicle.

Figure 2 shows a schematic perspective view of the two cross-beam tubes 16 and 17 of the suspension according to Figure 1.

In order to achieve a curvature of the crossbeam, the cross-beam tubes 16 and 17 are curved toward their hollow-tubular ends 4 and form an acute angle to the horizontal toward the tubular ends 5. The hollow-tubular ends 4 and 5 of the cross-beam tubes 16 and 17 have an internal diameter d1, which is capable of being plugged onto a tube attachment of the node elements 6 and 7 shown in Figure 1 and the connecting part 24 while maintaining a ring gap.

Figure 3 shows a schematic perspective view of a node element 7 of the suspension according to Figure 1. This node element 7 has a box shape 28 having a top side 20, which has an open-ing 37, which is used as a screw-on point 21 for the vehicle frame. A tube attachment 8 having an external diameter dA, which is slightly smaller than the internal diameter of the hollow-tubular ends 4 and 5 of the crossbeam tubes 16 and 17 shown in Figure 2, protrudes at an acute angle to the hori- zontal from a lateral surface 22 of the box-shaped node ele-ment 7.

In addition, the tube attachment 8 has an internal reinforce-ment structure 18 made of reinforcement ribs 19, which ensure that upon the materially-bonded connection of the tube at-tachment 8 to the hollow-tubular ends of the crossbeam tubes, the external contour of the tube attachment 8 remains dimen- sionally stable. To reinforce the tube attachment 8, stiffen-ing ribs 23 are situated on the box shape 28 on a lateral surface 22, which ensure, like node plates, that the tube at-tachment 8 is reinforced on the lateral surface 22.

Figure 4 shows a schematic perspective view of a connecting part 24 of the crossbeam tubes 16 and 17 according to Figure 2. Tube attachments 26 and 27, which can be connected to the hollow-tubular ends of the crossbeam tubes which are shown in Figure 2, protrude from the box-shaped connecting part 24 on lateral surfaces 38 and 39. In addition, mounting plates for a central mount 15 of the Watt linkage are situated on the lateral surfaces 38 and 39. The tube attachments 26 and 27 in turn have an internal reinforcement structure 18 made of reinforcement ribs 19. The box shape 28 of the connecting part 24 also has an internal reinforcement structure 18 hav-ing reinforcement ribs 19 inside the box shape 28, to form sufficient strength for the crossbeam.

Figure 5 shows a schematic perspective view of a crossbeam 3 of a suspension 1 according to a second embodiment of the ap-plication. Components having identical functions as in the preceding figures are identified by identical reference num-erals and are not explained further.

This second embodiment of the application differs from the first embodiment in that only one continuous crossbeam tube is provided for the crossbeam 3. This continuous one-piece crossbeam tube 25 has a central area 29 deformed by hydro-forming, which has edge surfaces on which mounting plates for the central mount 15 can be welded. The weld bonds are imple-mented by CO2 protective gas welding or 4IG soldering. The node elements 6 and 7 on the ends 4 and 5 of the continuous crossbeam tube 25 have the same structure as already shown in Figure 3, so that the hollow-tubular ends 4 and 5 of the crossbeam tube 25 can be shrunk onto the tube attachments of the node elements 5 and 6 with the aid of an electromagnetic pulse-welding method or pulse-shaping method and make a ring-shaped materially-bonded connection formed in partial areas of the hollow-tubular ends 4 and 5.

Figure 6 shows a schematic perspective view of a one-piece crossbeam tube 25 of a crossbeam according to Figure 5 in de- tail. Only three components are to be connected to manufac-ture a crossbeam with the aid of the one-piece crossbeam tube shown in Figure 6 having a polygonal central area 29, which is formed by hydroforming. Therefore, on the one hand, the number of electromagnetic pulse-welding methods is re-duced to two ring-shaped limited areas at the ends 4 and 5 of the one-piece crossbeam tube 25 and, in addition, the storage cost can be reduced, since only three parts are to be pre-pared and stored for a crossbeam.

Figure 7 shows a schematic perspective view of a tubular tor-sion element 14 of a semirigid axle 30. This tubular torsion element 14, as already shown in Figure 8, is connected to crank arms 33 and 34 and can be produced from an elastic alu- minum or titanium alloy and fixed by electromagnetic pulse- welding in a ring-shaped limited area on correspondingly pre-pared pipe attachments of the crank rods 10 and 11. Because of the electromagnetic pulse-welding, it is possible to con-nect the torsion spring element 14 made of light metal to a crank arms 33 or 34 made of cast steel, for example, by weld-ing.

Figure 8 shows a schematic perspective view of a rear axle 30 of a suspension 2 of a vehicle having a crossbeam 3 and node elements 6 and 7, and Figure 9 shows a schematic perspective view of the crossbeam 3 according to Figure 8 in detail, as already explained at the beginning, so that repetition can be dispensed with here.

List of reference numerals 1 suspension (embodiment of the application)

2 suspension (prior art)

3 crossbeam 4 hollow-tubular end hollow-tubular end 6 node element 7 node element 8 tube attachment 9 Watt linkage crank rod 11 crank rod 12 pivot joint 13 pivot joint 14 torsion spring element central mount 16 crossbeam tube 17 crossbeam tube 18 internal reinforcement structure 19 reinforcement ribs top side 21 screw-on point 22 lateral surface having tube attachment 23 stiffening rib 24 connecting part one-piece crossbeam tube 26 tube attachment 27 tube attachment 28 box shape 29 central area of 25 rear wheel axle 31 upper suspension arm 32 lower suspension arm 33 crank arm 34 crank arm free end of the crank arm 36 free end of the crank arm 37 opening at the screw-on point 38 lateral surface of 24 39 lateral surface of 24 joining or welding spot

Claims

Patent Claims 1. A suspension of a vehicle having a crossbeam (3) and node elements (6, 7) on the ends (4, 5) of the crossbeam (3), wherein -the node elements (6, 7) fasten the crossbeam (3) on the vehicle frame, -the crossbeam (3) of the suspension, made of light metals such as titanium or aluminum alloys, has hollow-tubular ends (4, 5) and -the node elements (6, 7) are each situated using a tube attachment (8) made of steel alloys, light metals, or fiber-reinforced plastics on the hollow-tubular ends (4, 5) of the crossbeam (3), -external dimensions of the tube attachments (8) are smaller than internal dimensions of the hollow-tubular ends (4, 5) of the crossbeam (3), and -the ends (4, 5) are fixed by material bonding on the tube attachments (8) of the node elements (6, 7) in a limited ring-shaped area.
2. A suspension of a vehicle according to Claim 1 having a Watt linkage (9) for the parallel guiding of rear wheels on a crank rod (10, 11) for each rear wheel, wherein -the crank rod (10, 11) is connected via a pivot joint (12, 13) to a rear frame of a vehicle frame, -the crank rods (10, 11) carrying the rear wheels are transversely connected via a torsion spring element (14), -the Watt linkage (9) is linked on a central mount (15) of the crossbeam (3), and -ends (4, 5) of the crossbeam (3) have node elements (6, 7) to the rear frame, and the crossbeam (3) has crossbeam tubes (16, 17) be-tween the central mount (15) and the node elements (6, 7), and the node elements (6, 7) have tube attachments (8) toward the crossbeam tubes (16, 17), whose external diameter (dA) is smaller than the internal diameter (d1) at ends (4, 5) of the crossbeam tubes (16, 17), and ends (4, 5) of the crossbeam tubes (16, 17) are fixed on the tube attachments (8) of the node elements (6, 7) by ma-terial bonding.
3. The suspension according to Claim 1 or Claim 2, wherein the hollow ends (4, 5) are fixed on the tube attachments (8) by electromagnetic pulse-welding.
4. The suspension according to one of the preceding claims, wherein the tube attachments (8) have an internal rein-forcement structure (18) made of crossing reinforcement ribs (19).
5. The suspension according to one of Claims 1 to 3, where- in the tube attachments (8) have an internal reinforce- ment structure (18) made of reinforcement ribs (19) ori-ginating radially from a center of the tube attachment (8)
6. The suspension according to one of the preceding claims, wherein the node element (6, 7) has a box-shaped struc-ture, and a screw-on point (21) to the vehicle frame is situated on a top side (20) of the box-shaped structure, and the tube attachment (8) is situated on a lateral surface (22) at an angle to the lateral surface (22), and reinforcement ribs (23) are situated between lateral surface (22) and tube attachment (8)
7. The suspension according to one of the preceding claims, wherein the node element (6, 7) is a diecast aluminum part, a diecast titanium part, a cast steel part, or a fiber-reinforced plastic part.
8. The suspension according to one of the preceding claims, wherein the crossbeam tubes (16, 17) have an extruded aluminum material, a cast steel tubular material, or a titanium alloy tubular material.
9. The suspension according to one of Claims 2 to 8, where-in the central mount (15) is situated on a connecting part (24) of the crossbeam tubes (16, 17) and is fixed on the connecting part (24) using CO2 welding or MIG soldering.
10. The suspension according to Claim 9, wherein the con- necting part (24) has tube attachments (8), on which tu-bular ends (4, 5) of the crossbeam tubes (16, 17) are fixed by electromagnetic pulse-welding.
11. The suspension according to one of the preceding claims, wherein the crossbeam tubes (16, 17) are constructed from multiple tube parts which are plugged one inside the other and electromagnetically pulse-welded.
12. The suspension according to Claim 8, wherein the con-necting part (24) is constructed as box-shaped and has tube attachments (26, 27) on both sides of the box shape (28), on which tubular ends (4, 5) of the crossbeam tubes (16, 17) are fixed by electromagnetic pulse-welding.
13. A vehicle having hollow-tubular structural elements made of light metals such as titanium or aluminum alloys, wherein the hollow-tubular structural elements have node elements (6, 7) made of light metals or fiber-reinforced plastics on their ends (4, 5), the node elements (6, 7) to the hollow-tubular structural elements having tube attachments (8), external dimensions (dA) of the tube attachments (8) are smaller than internal dimensions (d1) of the ends (4, 5) of the structural elements, and the node elements (6, 7) connect the hollow-tubular structural elements to the vehicle frame, and the ends (4, 5) of the structural elements are fixed by material bonding on the tube attachments (8) of the node elements (6, 7) in a limited ring-shaped area.
14. A method for manufacturing a crossbeam (3) of a suspen-sion of a vehicle, -manufacturing of two box-shaped node elements (6, 7) from a steel alloy, a light metal alloy, or a fiber-reinforced plastic having tube attachments (8) protruding on one side, which have an external diameter (dA), for the one-sided attachment on two crossbeam tubes (16, 17) -manufacturing a box-shaped central connecting part (24) from a steel alloy, a light metal alloy, or a fiber-reinforced plastic having tube attachments (26, 27) protruding on two sides for connecting two crossbeam tubes (16, 17) to form a crossbeam (3) and for attaching a central mount (15) for a Watt linkage; -manufacturing two crossbeam tubes (16, 17) from a steel alloy or a light metal alloy having hollow-tubular ends (4, 5), which have a larger internal diameter (d1) than the external diameter (dA) of the attachments (8, 26, 27) of the node elements (6, 7) and the central connecting part (24); -fixing one node element (6, 7) and one end (4) of a crossbeam tube (16) in a device for materially-bonded connecting while orienting the one-sided tube attachment (8) in the hollow-tubular end (4) and maintaining a radial ring gap; -performing a materially-bonded connection of the tube attachment (8) to the hollow-tubular end (4) in a limited ring-shaped area; -fixing and performing the further materially-bonded connections between the second crossbeam tube (17) and a further node element (7) as well as between the tube attachments (26, 27) of the central con-necting part (24) and the remaining ends (5) of the two crossbeam tubes (16, 17)
15. The method according to Claim 14, wherein electromagnet-ic pulse-welds are performed for the materially-bonded connection of the tube attachments (8, 26, 27) and the tubular ends (4, 5)