CN111283301A

CN111283301A - Joining device and joining method for producing a connection between components

Info

Publication number: CN111283301A
Application number: CN201911241474.4A
Authority: CN
Inventors: 海科·内夫; 斯蒂芬·赫希
Original assignee: Mahle International GmbH
Current assignee: Mahle International GmbH
Priority date: 2018-12-06
Filing date: 2019-12-06
Publication date: 2020-06-16
Anticipated expiration: 2039-12-06
Also published as: DE102018221157A1; CN111283301B

Abstract

The present invention relates to a joining device for connecting, in particular, plate-shaped components, which is used, in particular, for producing a battery housing of an electric or hybrid motor vehicle, and to a joining method for producing a connection between the components. The engagement device includes an engagement body having an engagement body stem defining a longitudinal axis. Furthermore, the coupling body comprises an engagement portion arranged at the first free end of the coupling body shank for connecting the coupling body to the first component and a force introduction portion for connecting the coupling body to the second component and for transmitting the engagement force. The force introduction section is arranged here at a second free end of the coupling body shank opposite the first free end. Furthermore, the coupling body shank comprises at least one elongation by means of which a change in the length of the coupling body shank in the direction of the longitudinal axis, in particular in the elasticity, can be brought about.

Description

Joining device and joining method for producing a connection between components

Technical Field

The invention relates to a joining device for connecting, in particular, plate-like components according to the preamble of claim 1. The invention further relates to a joining method for producing a connection between at least two components, and to a motor vehicle component produced according to said method.

Background

Joining devices and joining methods of the type mentioned at the outset have long been known and are used to permanently connect two or more components to one another. Standardized joining methods are, for example, blind riveting or spot welding, wherein each of these methods has distinct advantages. Particularly where lightweight construction is required, for example in the construction of motor vehicles and aircraft, there is a constant effort in research and development to optimise standardised joining methods. The result of these efforts is the so-called hybrid bonding method. Hybrid joining methods are characterized by a combination of two or more joining methods, for example in the case of stud welding, in which a stud or a threaded sleeve is welded to a component in order to be able to subsequently perform a screwed connection with another component.

In the joining method for connecting components, in particular components for battery housings of electric or hybrid motor vehicles, a large joining force is necessary. Ideally, these methods have low engagement forces and at the same time provide some elasticity at the joint.

It is therefore an object of the present invention to provide an improved joining method for connecting components.

Disclosure of Invention

With the present invention, this object is solved in particular by the subject matter of the independent claims. Advantageous embodiments are the subject of the dependent claims.

The basic idea of the invention is to provide a hybrid joining method combining the advantages of conventional welding, preferably spot welding, with the advantages of riveting, preferably hot riveting.

For this purpose, a joining device comprising a joining body is provided. The joint body includes a joint body shank and an elongated portion, wherein the joint body allows a length of the joint body shank in a direction of a longitudinal axis defined by the joint body shank to change, for example, when the elongated portion is more heated or more cooled. The joint body further comprises a force introduction portion for introducing a joining force and for supporting and/or connecting to the component and a joining portion. The engagement portion serves to produce a preferably firm engagement or form-fitting or force-fitting connection with the other component. The joining section is in particular a welding section from which an electric arc is scattered onto the component as part of the welding process in order to connect the component and the joint body to one another in a firmly joined manner. One or all of the components are preferably plate-shaped, in particular metal plate-shaped. The component may consist of a single piece or of a plurality of layers, i.e. be multilayered.

The advantage of the described joining body is that it can be adapted more easily to the components to be joined, since the shank of the joining body can, for example, be increased or decreased in cross section more easily. Furthermore, the axial length of the coupling shank can be adjusted, for example increased or decreased, relatively easily. A simpler connection between the different components can thus be achieved by means of the coupling body.

Another basic idea of the invention is to use the joint body as part of a joining method for producing an assembly of at least two components. The adapter may preferably comprise features according to the independent claims or according to the description. Within the scope of the joining method, a number of steps are provided:

(1) the joining body is introduced into the recess of the second part. In practice, the coupling body is introduced into the recess with the engagement portion in the front until the force introduction portion supports itself on the component, i.e. against said component. The joining section is guided to the first component in such a way that it is at a small distance from the first component. The distance between the engaging portion and the first part is, for example, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0 and even up to 2.0 mm.

The numbering of the components "first component" and "second component" should not be construed as limiting, but merely as a description.

(2) Energy is input into the coupling body or into the elongated portion thereof by means of a feeding system adapted to transfer and input energy. By the energy input, the joining body and/or the elongated portion may be heated or cooled, so that the joining body and/or the elongated portion expands, in particular expands or contracts, in the direction of the longitudinal axis. The energy transfer or energy input to the joining body is preferably effected by applying an electrical output electrically, for example by means of an arc or resistance welding, by means of a feed system. Alternative electrical heating methods are likewise conceivable, for example by means of induction. However, it is possible to provide contact heating or cooling by means of a feed system against the force introduction portion of the coupling body and to transfer energy by means of convection/heat conduction, i.e. contactlessly.

(3) When the joining body or the elongated portion thereof expands or contracts, a joining force is preferably applied to the first member, the second member, and the force introduction portion by means of the feeding system. Thus, the parts are pressed together and fixed (clamped).

(4) Electrical energy is preferably fed into the joining body by means of a feed system, wherein a welding process is actually established between the joining section and in particular the first component, by means of which a firm joint is produced between the component and the joining body. Alternatively or in addition, a welding process can also be established between the force introduction section and the other, in particular the second component, in order to produce a firm joint between the component and the joining body.

(5) The bonding force is removed and the bonded body is allowed to recover its original length. For example, the components and the interface may cool. In this way, the advantage is achieved that the first part and the second part are fixed to each other. In particular, this may be advantageous as part of the manufacture of battery housings for electric and hybrid motor vehicles.

The described joining method has the advantage that it can be carried out faster and is easier to automate, because the joining parts are connected to each other and fixed to each other as part of only one operation.

The invention also includes motor vehicle components such as battery housings and the like manufactured according to the above-described method steps.

Preferably, the elongated portion is more elastic than the surrounding portions. This makes the elongate portion more resilient, i.e. more movable, than adjacent portions of the joint body. This has the advantage that the coupling body is elongated more in the longitudinal direction. When a different material/smaller cross-section is used for the elongation than in the case of the rest of the coupling body, the elongation is more elastic than the rest of the coupling body, for example. The increased elasticity of the elongation also gives the joint body a certain bending deformability, i.e. bending elasticity, so that the joint produced with the joining method is also more elastic and ultimately more stable with respect to transverse or shear forces.

Furthermore, it is preferred that the joint shank has a waist in the region of the elongation. The cross-section of the joint in this portion is therefore smaller than the cross-section of the rest of the joint. The basic idea of this shape is that when heating the junction body, for example by means of electrical energy input through a feeding system for transferring and inputting energy, the junction body reaches high temperatures relatively quickly, in particular in a region of smaller cross section faster than the rest of the junction body. The elongation of the shank of the coupling body in the direction of the longitudinal axis can therefore be faster in time and preferably greater in amount compared to a coupling body without a waist. The advantage of this shape is that the coupling body expands faster and recovers its original length again faster. In this way, for example as part of the bonding process, shorter cycle times can be achieved. The joining method is therefore suitable to a high degree for automation.

In practice, the elongated portion is arranged between the first and second free ends of the stem of the coupling body. In this way, the joint body can be manufactured relatively economically.

Alternatively, a support portion for supporting the coupling body may be arranged between the first free end and the elongated portion and/or the second free end and the elongated portion. Each support portion comprises a larger cross-section than the elongate portion. The support portion ensures the mechanical strength of the joint body. This has the advantage that the joining method can also be operated with a higher joining force without the joint body yielding mechanically.

In particular, the elongated portion has a smaller cross-section or cross-sectional diameter than the support portion. In this way, the elongation of the elongated portion in the direction of the longitudinal axis is greater compared to the rest of the coupling body, with the same energy input by the feeding system, since the elongated portion heats up more quickly than the rest. This has the advantage that the elongation of the coupling body is specifically caused by the elongation portions, so that the elongation is predeterminable and controllable.

Preferably, the cross-section of the elongated portion is always smaller than the rest of the support portion or the shank of the coupling body, except for any transitions that may occur at the longitudinal ends of the elongated portion. The size of each cross-sectional diameter along the elongated portion, i.e., the elongated portion, is smaller than the size of the cross-sectional diameter of the shank or support portion of the coupling body. At the longitudinal ends of the elongated portion, the cross-sections for simplifying the transition may be equal in size.

Preferably, the joining device comprises a feeding system for transferring and inputting energy into the shank or elongated portion of the joining body. The feed system comprises a thermal energy supply device by means of which energy, in particular thermal energy, i.e. heating energy, can be input into the coupling body shank and/or the elongate portion, for example by means of induction or the like. However, it is also possible to provide contact heating or cooling by means of a feed system against the force introduction portion of the coupling body and to transfer energy by means of convection/heat conduction. In any case, the coupling stem and/or the elongated portion can be heated by means of a feeding system, so that they expand in the direction of the longitudinal axis.

Furthermore, the feeding system actually comprises an engagement force feeding device by means of which an engagement force can be optionally applied to the components to be engaged and/or the engagement body.

Furthermore, the feeding system actually comprises welding energy feeding means by means of which a welding current can be applied to the joining body and/or to the component to be connected and the joining body in order to weld the components to each other, in particular the joining body and the component arranged closest to the joining portion.

The coupling body shank may have a cylindrical or cylindrical cross section. In practice, the shank of the coupling body (except for the elongated portion which may be provided with a waist or a bend) is cylindrical or cylindrical in cross-section over its entire length along the longitudinal axis. This allows the production of the joined body to be carried out relatively simply and economically.

The joint body can be made of metal or of plastic or reinforced plastic.

The engagement portion may have a conical or frusto-conical or pointed end projecting away from the shank of the engagement body in the direction of the longitudinal axis. In this way, the welding tip is arranged at the free end of the coupling body in the manner described, as part of the welding process, preferably from said free end to the closest component an arc is formed. This has the advantage that the welding process can be performed in a relatively controlled manner.

It is also conceivable that the tip (also referred to as welding tip or joining tip) is pressed onto the component, for example by means of a joining force, in order to drive it into the component. In this way, the fastening of the joining body to the component (in particular the first component) can be carried out.

As an alternative to a pointed end, the engagement portion may have a flat engagement surface arranged transversely to the longitudinal axis. Thereby, the joined body having the joining portion can be pressed, for example, onto the member. This has the advantage that no clearance needs to be maintained between the engaging portion and the component, so that the engaging method or the engaging operation is faster.

The terms "joined" and "connected" are considered synonyms in the present invention.

Preferably, the joining portion is a welding portion for securely joining the joined body to the first member as part of a preferred electrical welding process. The preferred electrical energy required for the welding process is provided by the feed system of the joining device for transferring and inputting energy into the shank or extension of the joining body. The welding process may be configured as resistance welding or arc welding. The welding part for example comprises welding additives or alloys which are particularly advantageous for the welding process.

The joint body itself can be manufactured from a mixture of materials, such as plastic or reinforced plastic and metal. The joined body is generally made of a mixed material mixture. It is conceivable that the supporting part of the joint is made of metal and the rest of the joint is made of plastic, or vice versa. This has the advantage that different materials can be joined to one another. Due to the mixing of the materials, undesired effects such as corrosion, in particular contact corrosion, can also be prevented.

The joining portions may form-fitting/force-fitting portions for connecting the joining body to the first component. The joining body can thereby be arranged permanently, i.e. fastened, on one side to the second component with the force introduction section and on the second side to the first component with the joining section. This has the advantage that no welding process is required.

In summary, it should be noted that: the present invention relates to a joining device for connecting, in particular, plate-shaped components, which is used, in particular, for producing a battery housing of an electric or hybrid motor vehicle, and to a joining method for producing a connection between the components. The engagement device includes an engagement body having an engagement body stem defining a longitudinal axis. Furthermore, the coupling body has an engagement portion arranged at the first free end of the coupling body shank for connecting the coupling body to the first component and a force introduction portion for connecting the coupling body to the second component and for transmitting the engagement force. The force introduction section is arranged here at a second free end of the coupling body shank opposite the first free end. Furthermore, the coupling body shank comprises at least one elongation by means of which a change in the length of the coupling body shank in the direction of the longitudinal axis, in particular in the elasticity, can be brought about.

Drawings

Further important features and advantages of the invention can be taken from the dependent claims, the figures and the description of the figures in connection with the figures.

It is to be understood that the features mentioned above and still to be explained below can be used not only in the respective combinations stated but also in other combinations or alone without departing from the scope of the present invention.

Preferred exemplary embodiments are shown in the drawings and are explained in detail in the following description, wherein the same reference numerals relate to the same or similar or functionally identical components.

The figures each schematically show:

figure 1 shows a view of a joining device with a feed system and two plate-like parts,

figure 2 shows a view of the engaging means after engagement,

figure 3 shows a view of an alternative embodiment of the engaging means,

figure 4 shows a view of another alternative embodiment of the engaging means,

figures 5a-5d show the joining method with the joining device in different views,

fig. 6 shows a motor vehicle component with a joint manufactured according to the joining method described.

Detailed Description

Fig. 1 to 4 show a joining device 10 comprising a joining body 20 with a joining body shank 30. The coupling body shank 30 defines a longitudinal axis 35 that passes axially through the coupling body 20. Transversely to the longitudinal axis 35, a transverse axis 36 is arranged, relative to which the coupling body 20 expands radially. Furthermore, two plate-

like parts

40, 41 are shown which are or are to be connected by means of the joining device 10. For this purpose, the plate-

like members

40, 41 can expand parallel to each other and in particular perpendicular to the longitudinal axis 35 of the joining body 20, at least in the region of the joining body 20. Furthermore, the joining device 10 comprises a feed system 50 for inputting or feeding in preferably electrical energy.

In addition to the coupling body shank 30, the coupling body 20 comprises a force introduction portion 31 and an engagement portion 32.

In practice, the coupling stem 30 has an arched, in particular circular, cross section and two free ends and an axial extension 33. Basically, the extension 33 can be cylindrical and, like the coupling body shank 30, has an arcuate, in particular circular, cross section. Preferably, when the elongated portion 33 has a waist 34, i.e. the elongated portion 33 decreases in the transverse direction 36 from the initial cross section to a minimum and then preferably increases again to the initial cross section. The elongate portion 33 preferably has an arcuate, in particular circular, cross section which varies along the longitudinal axis 35.

Instead of or in addition to the waist 34, the elongated portion 33 may alternatively comprise another material. Instead of the waist 34, a curve not shown is basically also conceivable.

In practice, the coupling body stem 30 comprises at least one support portion 37 for supporting the coupling body 20 in the direction of the longitudinal axis 35 and in the direction of the transverse axis 36. The two support portions 37 are in the figures exemplarily arranged on the elongated portion 33, respectively, i.e. the support portions 37 are in front of and behind the elongated portion 33, respectively, in the direction of the longitudinal axis 35. In any case, the elongated portion 33 may have a cross-section corresponding to the cross-section of the support portion 37, which is indicated by a dashed line in fig. 1, for example. Preferably, however, the cross-section of the support portion 37 is slightly larger than the elongate portion 33. In the case of an extension 33 having a waist 34, the waist 34 is in fact configured such that it merges via a respective initial cross section into the adjacent support portion 37. The respective transition may have edges or be continuous.

The force introduction section 31 is arranged at the free end of the coupling body shank 30, where it is connected to the coupling body shank 30, for example in a firmly engaging manner. Alternatively, the force introduction portion 31 and the coupling stem 30 can be manufactured in one piece.

In fig. 1 to 4, the force introduction part 31 is formed in the manner of a rivet head, i.e. in the shape of a hemisphere 39 a. Alternatively, the force introduction portion 31 may, for example, have a cylindrical shape with a circular cross section 39b or a square cross section (not shown). A cylindrical shape with a circular cross-section 39b is indicated by a broken line in the drawing. In any case, the force introduction portion 31 supports itself on the member 40, so that the coupling body 20 is held, i.e. fixed, with respect to the

members

40, 41.

The engaging portion 32 of the engaging body 20 is arranged at the other free end of the engaging body shank 30, i.e. at the opposite free end of the engaging body shank 30 with respect to the force introduction portion 31.

In practice, the engagement portion 32 is configured as a tapered tip 42, also referred to as an engagement tip 42. However, instead of the tip 42, a truncated cone or a cylinder 38, preferably with a reduced cross section, may also be arranged.

The splicing device 10 includes a feed system 50, which is shown in phantom in fig. 1. The feed system 50 serves to transmit and feed electrical energy preferably into and into the coupling body 20 or the coupling body shank 30 and into the elongate portion 33.

The feeding system 50 comprises, for example, a thermal energy supply (not shown), by means of which energy can be input into the coupling stem 30 and/or the elongated portion 33 in order to heat the coupling stem 30 and/or the elongated portion 33. This is achieved, for example, by induction heating or by conduction heating or by current input into the joint shank 30 as part of resistance heating. In the case of resistive heating, the input current generates heat in the coupling stem 30, which heat depends in particular on the current and the resistance of the coupling stem 30, i.e. in the form of an electrical conductor through which the current flows, such as in the case of a helically wound filament or an incandescent lamp. In the case of conduction heating, the joint shank 30 is heated by a special high-frequency current flowing through it. In the figure, the energy transfer from the feeding system 50 to the elongated portion 33 based on the induction principle is only exemplarily represented by three waves 51.

The feeding system 50 actually comprises an engagement force feeding device (not shown) by means of which an axial engagement force 52 can be applied to the

components

40, 41 to be connected and to the joining body 20.

The engagement force 52 is imposed or exerted on both the force introduction portion 31 and the

components

40, 41. This is indicated in the figure by arrow 52.

Furthermore, the feeding system 50 actually comprises a welding energy feeding device (not shown), by means of which a welding current can be introduced into the joining body 20 and/or the

components

40, 41 to be connected, in order to weld the

components

40, 41 and the joining body 20 together by means of an electric arc.

Alternatively, the thermal energy feed device described above may additionally assume the function of a welding energy feed device, so that a separate welding energy feed device may be dispensed with. This may be achieved, for example, by the thermal energy feed providing different levels of electrical output. Basically, the thermal energy feed means for heating the coupling shank 30 can provide a lower electrical output level than during the welding process, which is preferably carried out at a higher electrical output level.

In the drawing it is exemplarily shown how the joining body 20 electrically contacts on the one hand the area of the force introduction portion 31 and on the other hand the

electrical contact members

40, 41 by means of the

electrical conductors

53, 54 connected to the feeding system 50. As a result, an arc may be formed between the joining tip 42 of the joining portion 32 and the

members

40, 41, which results in melting of the joining tip 42 and the

members

40, 41 as part of the welding process, so that a firm joint may be formed between the joined body 20 and the

members

40, 41. Fig. 6 shows an exemplary embodiment of a corresponding connector 71.

After the welding process has ended, the

components

40, 41 and/or the joining body 20 and/or the elongate portion 33 are cooled, wherein the currently connected

components

20, 40, 41 are fixed to one another. By the fixation of the components, the resistance of the crash structure, in particular the resistance of the motor vehicle component 80 described further below, can be increased. This has the advantage that the motor vehicle component 80 is relatively strong and can absorb large forces, for example in the event of a crash.

During the cooling process, the preload force, in particular a fraction (e.g. half or quarter) of the preload force, may optionally result in a small displacement of the

components

40, 41 relative to each other, which is indicated in fig. 2 by a double arrow marked with reference numeral 60. Such a displacement may result in the two

components

40, 41 abutting each other, for example in a fluid-tight manner, or abutting another component not shown, by means of a force-fitting frictional connection. Preferably, in the case of a battery housing or motor vehicle part 80, a defined elastic and/or plastic deformation of the

parts

40, 41 and/or the housing material takes place as a result of the small displacement 60, in order to seal the lid, for example.

In fig. 3, an alternative embodiment of the joining device 10 is shown, which, in contrast to the above-described embodiments, does not have an extension 33, but only a continuous support portion 37. At the free end of the coupling body 20, a cylinder 38 is arranged instead of the tip 32. The remaining method features and apparatus features are equally applicable.

Fig. 5a, 5b, 5c, 5d show a bonding method 70 using the bonded body 20.

According to the joining method 70, the joining body 20 is introduced through the recess 63 in the member 40 so that the force introduction portion 31 supports itself on the member 40. The engaging portion 32 or the engaging tip 42 is here arranged at a small distance from the other part 41. The small distance between the engagement tip 42 and the

parts

40, 41 is shown in fig. 5 a.

After this, energy is input into the coupling body 20 and/or the elongated portion 33 by means of a feeding system shown in fig. 5a, 5b and 5 c. Thereby, the coupling body 20 and/or the elongated portion 33 is heated to expand, i.e. increase in length, the coupling body 20 and/or the coupling body stem 30 in the direction of the longitudinal axis 35, which is illustrated in fig. 5b by the double arrow 43. The energy input is effected exemplarily by means of induction, which is represented in the figure by three waves 51.

In a next step, an engagement force 52 is applied to the force introduction portion 31 and the

components

40, 41 by means of the feeding system 50. The joining forces are represented by arrows 52, respectively, in which the joined body 20 is still heated, i.e. still expanded. In any event, the application of the joining force 52 ensures that the

components

40, 41 in the heated state are pressed together and secured together.

In a further step, which is illustrated in fig. 5c and 5d, electrical energy is fed into the joining body 20 and the

components

40, 41 by means of the feed system 50, so that an arc is formed between the joining section 32 or the joining tip 37 and the component 41. In other words, the welding process is established. In any case, a firm joint is created between the coupling body 20 and the

components

40, 41 at the joint. This secure engagement is shown in fig. 5 d. During the welding process, the feeding system 50 preferably does not introduce any energy for heating the elongated portion 33 into the elongated portion 33 or the joined body 20. The engagement force 52 applied by the feed system 50 is preferably maintained during the welding process. Alternatively, the engagement force may be removed/released.

In the final step, the engagement force 52 is released. Furthermore, the joined body 20 can be cooled and restored to its original length so that the

components

20, 40, 41 are fixed to each other.

In fig. 4, a further alternative embodiment of the joining device 10 is shown, which, in contrast to the above-described embodiments, has instead of the welding portion 32 a shape/force-fitting portion for connecting the joining body to the first component 41.

The joint portion 32 and the welding process can be omitted. The tightening screw 61 and the tightening nut 62 replace, for example, the engagement portion 32 and the engagement tip 42. In fig. 4, a fastening screw 61 and a fastening nut 62 fitted to the fastening screw 61 are exemplarily arranged on the joint body shank 30.

In contrast to the joining method 70 described above, such a joined body 20 is inserted through a first notch 63 of a component 40 and through a second notch 64, positioned oppositely in the component 41, aligned with this notch 63. Thereby supporting the force introduction portion 31 on the one part 40 while the fastening screw 61 protrudes through the second recess 64. As in the bonding method 70 described above, the bonded body 20 is heated at the elongated portion by means of the feeding system 50 (not shown in fig. 4), so that the bonded body 20 expands in the direction of the longitudinal axis 35. When the joint body 20 is warmed up and elongated in the manner described, the fastening nut 62 is fitted onto the fastening screw 61 of the joint body 20. After cooling, the fastening nut 62 and the

parts

40, 41 are fixed to one another when the joint shank 20 has again its original length.

In fig. 6, a motor vehicle component 80 is shown, in particular a battery housing for an electric or hybrid motor vehicle. The motor vehicle component 80 has a series of identical joints 71, which are manufactured according to the joining method 70 described above. For example, a coupling body 20 according to the above-described features is used in the process.

Claims

1. A joining device (10) for connecting in particular plate-shaped components, in particular for producing a battery housing of an electric or hybrid motor vehicle,

-having a coupling body (20) comprising a coupling body shank (30) defining a longitudinal axis (35),

-having an engagement portion (32) arranged at a first free end of the coupling body shank (30) for connecting the coupling body (20) to the first component (40),

and having a force introduction section (31) for connecting the joining body (20) to the second component (41) and for transmitting a joining force (52),

-wherein the force introduction portion (31) is arranged at a second free end of the coupling body shank (30) opposite to the first free end,

-wherein the coupling stem (30) comprises, between the first free end and the second free end, at least one elongated portion (33), by means of which at least one elongated portion (33) a variation of the length (43) of the coupling stem (30) in the direction of the longitudinal axis (35) can be induced.

2. The joining device of claim 1,

-the elongated portion (33) is more elastic than its surrounding portion (37); and/or

-said elongated portion (33) has a waist (34).

3. The joining device according to any one of claims 1 or 2,

-said elongated portion (33) is arranged between a first free end and a second free end of the coupling stem (30), or

-between the first free end and the elongated portion (33) and/or between the second free end and the elongated portion (33) there is arranged a support portion (37) for supporting the coupling body (20).

4. A joining device according to claim 3, characterized in that the cross section of the elongated portion (33) between its longitudinal ends is always smaller than the rest of the support portion (37) or the joint shank (30).

5. Joining device according to any one of the previous claims, characterized in that said joining device (10) comprises a feeding system (50) for transferring and inputting energy into the joining body shank (30) or elongated portion (33) to heat the joining body shank (30) or elongated portion (33) so that it expands in the direction of the longitudinal axis (35) and/or to introduce electrical energy into the joining body (20).

6. The joining device according to any one of the preceding claims,

-the coupling shank (30) is cylindrical or cylindric in cross-section over its entire length along the longitudinal axis (35), or

-the joining body (20) is made of metal or plastic or reinforced plastic.

7. The joining device according to any one of the preceding claims, characterized in that said joining portion (32) comprises a conical or truncated cone or tip (37) projecting away from the joining body shank (30) in the direction of the longitudinal axis (35) or a joining surface (38) arranged transversely to the longitudinal axis (35).

8. Joining device according to any of the preceding claims, characterized in that the joining portion (32) is a welding portion for firmly joining the joining body (20) to the first component (40) as part of a welding process, wherein the energy required for the welding process is provided by a feeding system (50) of the joining device (10) for transferring and inputting energy into the joining body shank (30) or the elongated portion (33).

9. Joining device according to any one of the preceding claims, characterized in that the joining portion (32) forms a shape/force-fitting portion for connecting the joining body (20) to the component (41).

10. A joining method for producing a connection between at least two components, in particular for producing a battery housing for an electric or hybrid motor vehicle,

-having an engagement portion (32) arranged at a first free end of the coupling body shank (30) for connecting the coupling body (20) to the first component (41), and

-having a force introduction portion (31) for connecting the coupling body (20) to the second component (40) and for transmitting a coupling force (52), wherein the force introduction portion (31) is arranged at a second free end of the coupling body shank (30) opposite to the first free end,

-wherein the coupling stem (30) comprises an elongated portion (33), by means of which elongated portion (33) an elastic change of the length (43) of the coupling stem (30) can be induced,

the method comprises the following steps:

1) introducing the joining body (20) into a recess (63) arranged on the second component (40) such that the force introduction section (31) supports itself on the component (40) and the joining section (32) is arranged at a small distance from the first component, in particular 0.1mm to 2.0,

2) energy is input into the joining body (20) and/or the elongated portion (33) by means of a feeding system (50) for transferring and inputting energy to heat the joining body (20) and/or the elongated portion (33) such that the joining body (20) and/or the elongated portion (33) expand in the direction of the longitudinal axis (35),

3) applying a joining force (52) to the first member (41), the second member (40) and the force introduction portion (31) of the joined body (20) by means of the feeding system (50) so that the portions in the heated state are pressed together and fixed together,

4) electrical energy is fed into the joining body (20) and/or the elongated portion (33) by means of the feeding system (50) such that a welding process is established between the joining portion (33) and the first component (41) for producing a firm joint between the joining body (20) and in particular the second component (40),

5) the joining force (52) is released and the joining device (10) is cooled, wherein the expansion (43) caused by step 2) is reduced, such that the first component (41) and the second component (40) are fixed to each other.

11. A motor vehicle component, in particular a battery housing for an electric or hybrid motor vehicle, characterized in that at least one joint (71) is realized according to the method of claim 10 and/or at least one joint (71) comprises a joint body (20) according to any one of claims 1 to 9.