Floor structure for body of electrically drivable motor vehicle

Abstract

The invention relates to a floor structure (1) for the body of an electrically drivable motor vehicle, comprising side sills (2) which extend along the outside of the vehicle and which are connected to one another by means of a plurality of cross-members (3). In order to improve the performance of the floor structure (1), in particular in the event of a side collision of the motor vehicle, according to the invention the at least one cross member (3) has a weakening (5, 6, 7, 8) in the connection region (A) to the side sill (2).

Description

Technical Field

[0001] The present invention relates to a floor structure for the body of an electrically drivable motor vehicle according to the preamble of claim 1. Background Art

[0002] Such floor structures are known from the prior art and generally include side sills extending along the outer side of the vehicle, and the side sills are interconnected by a plurality of cross members, such as corresponding seat cross members.

[0003] Another trend of such floor structures is that the memory housing provided below the floor structure is no longer reinforced by corresponding cross members extending within the memory housing, because these cross members require valuable structural space for the storage cells of the energy storage of the electrically drivable motor vehicle within the memory housing. Therefore, since the cross members that used to extend within the memory housing are no longer provided, the cross members provided above the vehicle floor of the floor structure must be constructed correspondingly more stably and rigidly, so as to ensure sufficient stiffness, for example, during a side collision of the motor vehicle, especially when hitting a pole, so that the storage cells of the energy storage provided within the memory housing are not loaded. On the other hand, the cross members should also be able to deform within a certain limit when absorbing collision energy, so as to be able to dissipate the collision energy sufficiently. Summary of the Invention

[0004] Therefore, the object of the present invention is to provide a floor structure of the type described at the beginning, which has improved performance when side-colliding with the body of the motor vehicle.

[0005] According to the present invention, this object is solved by a floor structure having the features of claim 1. Advantageous embodiments with suitable expansion schemes of the present invention are the technical solutions of the dependent claims.

[0006] The floor structure according to the present invention includes side sills extending along the outer side of the vehicle, and the side sills are interconnected by a plurality of cross members.

[0007] In order to improve the performance of the floor structure here, especially during a side impact of a motor vehicle, it is provided according to the invention that at least one crossmember has a weakening portion in the connection region with the side sill. Thus, according to the invention, the at least one crossmember is constructed extremely stably in the middle region in order to correspondingly protect the storage cells of the energy storage located below this floor structure or to limit the deformation of the floor structure and the memory housing. But on the other hand, by means of a targeted end-side weakening of the crossmember in the corresponding connection region with the side sill, the strength or stiffness should be reduced in a targeted manner, so that when hitting the corresponding, laterally arranged side sill during a side impact, such a support can be generated by means of the crossmember, which support can yield correspondingly well while absorbing the impact energy. In other words, thus, the crossmember, which is extremely rigid and hard in the middle region, is weakened in a targeted manner on its outer side, so that it can achieve particularly good deformation while absorbing the impact energy within a certain limit, i.e., for example, over the length of the connection region. Thereby, an improved accident performance of the floor structure during a side impact is obtained overall, while ensuring that no such deformation occurs in the middle region of the floor structure, since the storage cells of the energy storage are arranged below the floor structure in this region.

[0008] The invention is used here in particular in such a floor structure in which the memory housing arranged below the floor structure is no longer reinforced by corresponding crossmembers extending within the memory housing, since these crossmembers require valuable structural space in the memory housing for the storage cells of the energy storage of the electrically drivable motor vehicle.

[0009] In another design of the invention, it has proven advantageous here that the weakening portion is produced by at least one reduced wall thickness of the profile of the at least one crossmember and / or by at least one change in the material properties of the profile of the at least one crossmember, in particular a change in strength. Alternatively, the weakening portion can also be formed by at least one notch within the profile of the crossmember. Of course, these measures can also be superimposed. As a result, in any case, the desired weakening of the crossmember on the outer side in the connection region with the corresponding side sill is achieved in order to achieve the described effect.

[0010] Another advantageous embodiment of the invention provides that the connection region has a plurality of interconnected regions with weakening portions. Thus, for example, the wall thickness of the profile of the corresponding crossmember can be gradually increased from the outside to the inside or the strength can also be gradually increased from the outside to the inside, for example, within the scope of the connection region of the side sill. By appropriately designing the corresponding notches, the desired deformation characteristics of the corresponding crossmember can also be achieved.

[0011] In any case, it should be basically achieved that the weakening portions of the individual regions decrease from the outside to the inside, so that the crossmember is constructed softer on the outside and gradually harder towards the inside in the connection region.

[0012] In order to obtain a particularly high rigidity of the crossmember, especially in the middle region, it is particularly advantageous if the profile of the crossmember is designed as a roll-formed profile.

[0013] Furthermore, it is advantageous if the crossmember is fixed to a laterally arranged side sill by means of an adapter. In this way, a largely undesired relative movement of the outer end of the crossmember relative to the corresponding side sill due to forces caused by an accident can be avoided.

[0014] In a further design of the invention, the adapter is arranged such that it at least covers the connection region of the side sill with a weakening portion. In this way, a corresponding guidance of the side sill can be achieved particularly effectively in the case of deformation caused by an accident.

[0015] Finally, it has been shown to be advantageous if the adapter is made of a metal sheet as a bent part. Thereby, the adapter can be manufactured particularly simply and a corresponding degree of deformation can be achieved.

[0016] Other features of the invention result from the claims, the drawings and the description of the drawings. The features and feature combinations mentioned above in the description and those mentioned below in the description of the drawings and / or shown individually in the drawings can be used not only in the respectively given combinations, but also in other combinations or individually. Description of the Drawings

[0017] The invention will now be explained in detail on the basis of preferred embodiments and with reference to the drawings. The drawings are as follows:

[0018] Figure 1 A partial and perspective sectional view showing a section extending in the vehicle transverse direction or the vehicle height direction through the floor structure according to the invention, wherein in the cross-sectional view, a side sill extending on the outer side of the vehicle is visible, to which a crossmember of the floor structure above the vehicle floor is connected, and the crossmember has a weakening portion in the connection region with the side sill; and

[0019] Figure 2 A further partial and perspective sectional view showing the floor structure having an adapter by means of which the crossmember is fixed to a laterally arranged side sill. Detailed Description of the Invention

[0020] Figure 1The side sill 2 extending along the vehicle outside is shown in a partial and perspective sectional view of a section extending in the vehicle height direction or the vehicle transverse direction through the floor structure 1 of a body of an electrically drivable motor vehicle. One of the plurality of cross members 3 is connected to the side sill, and the cross member extends horizontally and in the vehicle transverse direction. Such side sills 2 are also provided on the opposite vehicle outsides, and the corresponding cross members 3 are connected to the side sills with their opposite ends. In the present case, for example, it relates to a seat cross member that extends horizontally and in the vehicle transverse direction in the area of the front seat row of the vehicle.

[0021] In the present case, a memory housing (not visible) for an energy storage for supplying electrical energy to the electric drive device of a sedan is provided below the floor structure 1, and the memory housing extends, for example, between the two side sills 2 and below the corresponding cross members 3 of the floor structure 1. In the present case, in Figure 1 a floor element, such as the floor 4, is visible, which extends below the lower side of the cross member 3 or the cross member 3 is placed on or connected to the floor. The floor 4 can be formed by the upper part of the housing of the memory housing of the energy storage or by a separate plate member, etc. In this case, the upper part of the housing of the memory housing is arranged spaced below the floor 4.

[0022] Since it is especially provided that no cross members are provided in the memory housing to laterally reinforce the floor structure 1 and the energy storage provided below the floor structure 1, the corresponding cross members 3 must be constructed correspondingly rigidly and stably or have high strength in the present case. In the present case, each cross member, such as the cross member 3, is formed by a hollow profile, for example, made of high-strength or extremely high-strength steel. Of course, other design options for the cross member 3 can also be considered. The cross member 3 and the floor 4 together form a corresponding chamber profile here, which helps to reinforce the floor structure.

[0023] As now shown by Figure 1 it can be seen that the cross member 3 has one or currently a plurality of weakening portions 5, 6, 7, 8 in the connection region A with the side sill 2. These weakening portions 5 to 8 are generated, for example, by different wall thicknesses of the profile of the cross member 3 and / or by a change in at least one material property, especially the strength, of the profile of the corresponding cross member 3. Thus, for example, the outermost weakening portion 5 can be formed by a smaller wall thickness than the weakening portions 6 to 8 arranged on its inner side. These weakening portions 6 to 8 can also be formed, for example, by a gradually increasing wall thickness of the profile of the cross member 3. Thus, preferably, the cross member 3 has at least one weakening portion on the outer side in the connection region A with the side sill 2. Or in other words, for example, the wall thickness can be reduced from the inside out through the weakening portions 8 to 5. In addition, the weakening portions 5 to 8 can also be formed by a respectively reduced strength or by introducing at least one notch in the region of one of these weakening portions 5 to 8.

[0024] As a result, in any case, the crossmember 3 should have a minimum strength or stiffness near the connection portion with the side sill 2 and gradually become more rigid or stiffer towards the vehicle center based on an appropriate number of weakening portions 5 to 8 until the crossmember 3 has its full stiffness and strength at the connection with the connection area A or in the middle area of the crossmember 3.

[0025] In addition, according to Figure 1 It can be seen that the crossmember 3 is supported on the inner panel or inner shell 9 of the side sill 2 on the outside, and the inner panel or inner shell forms a chamber 11 with a plate member 10 having a substantially U-shaped cross-section. An energy absorption element 12 is arranged in the chamber. The energy absorption element is supported on the inner member 9 of the side sill 2 and is thus supported on the crossmember 3 through the inner member.

[0026] If a car now has a side collision, for example, hits a pole, on the one hand, the crossmember 3 ensures that the energy absorption element 12 is supported stably enough and can deform when absorbing the collision energy. In addition, if additional collision energy needs to be absorbed, the crossmember 3 can deform correspondingly when absorbing the collision energy based on at least one of the weakening portions 5 to 8 in its connection area A with the side sill 2.

[0027] On the contrary, the middle area of the crossmember 3 or the floor structure 1 is arranged outside the weakening portions 5 to 8 and is thus constructed so rigid that the floor structure 1 and the memory housing arranged below it basically do not deform, and such deformation may cause damage to the storage monomers of the energy memory arranged in the memory housing, and such deformation may ultimately trigger a thermal event. The present invention is therefore based on the following basic concept: accident energy should be additionally absorbed in the connection area A of the crossmember 3 with the side sill 2, and the crossmember 3 should not deform in such a way that significant damage is caused to the storage monomers of the energy memory.

[0028] Figure 2 Similar to Figure 1 The partial and perspective sectional views showing a section extending through the floor structure 1 in the vehicle height direction or the vehicle transverse direction are shown. In particular, it can be seen here that the crossmember 3 is fixed to the laterally arranged side sill 2 through an adapter. The adapter 13 is placed on the upper side on the connection area A of the side sill 3 here and preferably extends at least over the length of the connection area A. This means that the adapter 13 preferably extends over at least approximately the entire length of the weakening portions 5 to 8 of the crossmember 3.

[0029] The adapter 13 is currently, for example, made of a metal plate as a bent part and is connected to the inner part 9 of the side sill 2 by means of corresponding tabs 14 through corresponding joining connections, such as spot welding connections, etc. In addition, corresponding bolt connections 15 are provided, through which the adapter 13 is bolted to the energy absorption element 12 through the inner part 9 of the side sill 2. In addition, the adapter can also be connected to the cross member 3 through corresponding joining connections, etc.

[0030] By means of the adapter, in particular after a force caused by an accident is exerted during a side impact, a particularly advantageous retention and support of the cross member 3 relative to the side sill 2 is achieved, so that, when a force caused by an accident is exerted during a side impact, the cross member 3 does not, for example, yield in the vehicle height direction upwards or in a similar direction.

[0031] List of reference numerals

[0032] 1 Floor structure

[0033] 2 Side sill

[0034] 3 Cross member

[0035] 4 Floor

[0036] 5 Weakening part

[0037] 6 Weakening part

[0038] 7 Weakening part

[0039] 8 Weakening part

[0040] 9 Inner shell

[0041] 10 Plate part

[0042] 11 Chamber

[0043] 12 Energy absorption element

[0044] 13 Adapter

[0045] 14 Tab

[0046] 15 Bolt connection

[0047] A Connection area

Claims

1. Floor structure (1) for the body of an electrically drivable motor vehicle, the floor structure having side sills (2) extending along the outer side of the vehicle, the side sills being interconnected by a plurality of cross members (3). Characterized in that, at least one cross member (3) has weakening portions (5, 6, 7, 8) in the connection region (A) with the side sill (2).

2. Floor structure (1) according to claim 1, Characterized in that, the weakening portions (5, 6, 7, 8) are produced by at least one reduced wall thickness of the profile of the at least one cross member (3) and / or by at least one change in the material properties, in particular the strength, of the profile of the at least one cross member (3).

3. Floor structure (1) according to claim 1 or 2, Characterized in that, the weakening portions (5, 6, 7, 8) are formed by at least one notch in the profile of the at least one cross member (3).

4. Floor structure (1) according to any one of the preceding claims, Characterized in that, the connection region (A) has a plurality of regions of the weakening portions (5, 6, 7, 8) connected to each other.

5. Floor structure (1) according to claim 4, Characterized in that, the weakening portions (5, 6, 7, 8) of the respective regions decrease from the outside to the inside.

6. Floor structure (1) according to any one of the preceding claims, Characterized in that, the cross member (3) is formed by a roll-formed profile.

7. Floor structure (1) according to any one of the preceding claims, Characterized in that, the cross member (3) is fixed to the laterally arranged side sill (2) by means of an adapter (13).

8. Floor structure (1) according to claim 7, Characterized in that, the adapter (13) at least covers the connection region (A) of the side sill (2) having the weakening portions (5, 6, 7, 8).

9. Floor structure (1) according to claim 7 or 8, Characterized in that, the adapter (13) is made of a metal sheet and is a bent part.

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