FLOOR STRUCTURE FOR A PASSENGER CAR AND MODULAR SYSTEM FOR A CAR BODY

Description

[0001] The invention relates to a floor structure for a passenger car according to the preamble of claim 1 and a modular system for a car body according to the preamble of claim 11.

[0002] Such a floor structure is known, for example, from EP 2 468 609 B1 and comprises side sills, each with a cavity, which are laterally connected to a vehicle floor and between which cross members extend. To protect an energy storage device extending below the vehicle floor and between the side sills, particularly from side impacts, corresponding energy absorption elements are arranged along the respective side sills. In the present case, these energy absorption elements are arranged on the side of the energy storage device's housing and are designed, for example, as extruded or rolled profiles. Furthermore, it is known from other embodiments to arrange such energy absorption elements not on the side of the housing, but rather within the cavity of the respective side sill.

[0003] WO 2021 / 071410 A1 and WO 2019 / 059821 A1 each describe a floor structure with side sills, cross members running at the same height between the side sills, and energy absorption elements running along the side sills. These energy absorption elements have a wave-like shape along their length and are arranged in the vertical direction of the vehicle with uniform overlap with the cross members. Similar energy absorption elements are also described in JP 2010 274848 A.

[0004] All known floor structures share the common feature that, in order to protect the energy storage system in the event of a side collision, extremely large, weight- and cost-intensive energy absorption elements or profiles are used. These extend along the vehicle's longitudinal axis and, for example, occupy almost the entire cross-section of the cavity in the respective side sill. This is due, for instance, to the fact that the respective energy absorption element, being large and extending along the entire vertical direction of the vehicle, must bear against the floor structure and / or the energy storage system.

[0005] The object of the present invention is therefore to create a floor structure of the type mentioned above which is optimized as much as possible in terms of cost, weight and installation space. In particular, the respective energy absorption element should be adapted to the contour of the vehicle's floor structure in a particularly favorable manner.

[0006] This problem is solved according to the invention by a floor structure with the features of claim 1 and a modular system with the features of claim 11. Advantageous embodiments with favorable further developments of the invention are specified in the dependent claims.

[0007] The floor structure according to the invention comprises a side sill on each side of the vehicle, each side sill defining a cavity and connecting to a vehicle floor located between the side sills. Preferably above a floor panel or similar component of the vehicle floor, cross members extend between the side sills, arranged at different heights along the longitudinal direction of the vehicle relative to its height. Furthermore, profile-like energy absorption elements extend along the side sills, which, according to the invention, have at least one non-linear, in particular a curved, kinked, or similar, section along their length and extend at least approximately over the entire length of the side sill.The partially non-linear, curved, or angled design of the respective energy absorption element makes it possible to optimally adapt it to the shape and contour of the body-floor structure, thus significantly improving the vehicle's crash performance and occupant safety in the event of a side impact. For example, and in particular, it allows for improved support of the respective lateral energy absorption elements to the cross members, which are arranged at different heights along the longitudinal axis of the floor structure relative to the vehicle's height.The non-linear or curved shape of the energy absorption elements ensures optimal support against the crossbeams located on the inside of the energy absorption elements in the transverse direction of the vehicle, preferably against all crossbeams arranged longitudinally along the energy absorption elements and extending between the side sills. This improved support allows for smaller dimensions of both the floor structure components and the energy absorption elements themselves, resulting in weight and space savings as well as cost-effective manufacturing of the floor structure.

[0008] In a further embodiment of the invention, it has proven advantageous to arrange the energy absorption elements within the respective cavity of the corresponding side sill. In combination with the respective side sills, the energy absorption elements thus enable the creation of side sill structures that ensure a large-scale and efficient absorption of the force in the event of a side impact with a barrier or a vehicle.

[0009] In a further embodiment of the invention, a front and / or rear end region of the energy absorption elements is designed as a non-linear length region of the energy absorption element. This makes it possible, for example, for the respective cross members to be arranged in a central region of the vehicle floor above a floor panel and in a front and / or rear region, for example, below the vehicle floor or the corresponding floor panel.

[0010] In this context, it has proven advantageous if the front and / or rear end region of the energy absorption element is sloped downwards relative to a central region. However, upwardly sloping end regions of the energy absorption elements would also be theoretically conceivable.

[0011] Another advantageous embodiment of the invention provides that the energy absorption elements in the central region extend at least substantially at the level of the respective cross members running above the vehicle floor. In the central region of the energy absorption elements, the desired optimal support and force transmission of the respective lateral energy absorption elements towards the center of the vehicle is thus achieved.

[0012] Equally favorable support for the respective energy-absorbing elements in the front or rear end area is achieved when they are positioned at the level of a respective crossmember running below the vehicle floor. Experience has shown that crossmembers are typically located below the vehicle floor or floor panel in the front and rear end areas, for example, to create a frame-like stiffening of the floor structure in conjunction with the respective side sills.

[0013] In a further embodiment of the invention, it has proven advantageous if the energy absorption elements in the central area extend at least substantially above an energy storage device arranged below the vehicle floor and between the side sills. Consequently, if the floor structure is used, for example, for an electric vehicle with an underfloor arrangement of an energy storage device, the corresponding arrangement of the energy absorption elements allows for the avoidance or minimization of cross members within the energy storage device, which in turn enables a saving of installation space and vehicle weight as well as a more cost-effective design of the energy storage device.Furthermore, this increases the volume usable for energy storage within the housing of the energy storage system, which means, for example, that more battery cells can be arranged within the energy storage system or the storage housing, thus also increasing the vehicle range.

[0014] In a particularly advantageous embodiment of the invention, it is provided that the respective energy absorption element, which is assigned to one of the two side sills and extends approximately along the longitudinal axis of the vehicle, does not extend exclusively in a straight line, as the side sill in particular does, but has at least one curved area around the transverse axis of the vehicle, whereby in the side view of the motor vehicle a support / overlap area of ​​the energy absorption elements that is as full-surface as possible on / with at least one cross member structure extending along the transverse axis of the vehicle between the two side sills above the installation space accommodating the energy storage unit, and additionally at least one support / overlap area with a cross member structure in front of the energy storage installation space or at least one support / overlap area with a cross member structure behind the energy storage installation space.In a further embodiment, it may be provided that the support / covering area of ​​the energy absorption elements on / with a crossbeam structure is located in front of the energy storage space or the support / covering area of ​​the energy absorption elements on / with a crossbeam structure is located behind the energy storage space in the vehicle's vertical direction below the support / covering areas of the energy absorption elements on / with the crossbeam structures above the energy storage space.

[0015] Finally, it has proven advantageous if the height of the side sills corresponds at least substantially to three times the height of the energy absorption elements. This results in a further optimization of the floor structure, as the energy absorption elements achieve optimal effectiveness despite their limited height.

[0016] Furthermore, it has proven advantageous if the height of the energy absorption elements corresponds at least substantially to the height of the crossbeam structures above the vehicle floor. This results in a further optimization of the floor structure, as the energy absorption elements can achieve optimal effectiveness despite their limited height.

[0017] The subject matter of the invention also relates to a modular construction system with the features of claim 11, which serves to reinforce the two side sills or the side sill structure of the motor vehicle body at the positions necessary for the protection of the respective energy storage device, in particular in motor vehicles that are based on a common body platform, but which, compared to the base vehicle, i.e. the body of the base vehicle from which the body of at least one other motor vehicle of this model series is created by modifications of the body, have to meet, for example, increased requirements with regard to vehicle mass, high-voltage safety (for example, protection of electrical components of electric vehicles), occupant safety or dimensional concept variations (for example, wheelbases).The energy absorption elements can be adapted to the resulting, diverse positions of the crossmember structures by varying the number and geometry of the curvature zones, thereby improving vehicle safety in the event of a side impact with an opposing vehicle / crash barrier in a weight- and cost-optimized manner. This is achieved by optimizing the size and position of the support / overlap areas of the energy absorption elements on the crossmembers / crossmember structures, thus preventing intrusion of the body structure into the energy storage compartment during the impact. The design of the respective floor structure of the vehicle bodies is preferably carried out according to one or more of the patent claims relating to the floor structure and / or from the description in the figures.

[0018] In an advantageous embodiment of the modular system, all variant-specific energy absorption elements of the respective vehicle floor structure exhibit a non-linear length. Alternatively, if a combustion engine variant is provided, its side sills may also be equipped with energy absorption elements, or these elements may be assigned to side sills with a linear length. This is because, for example, the lower weight of this vehicle compared to an electrically powered vehicle with an energy storage system means that the bodywork is not subject to such high demands in the event of a side impact.

[0019] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0020] They show: Fig. 1a, 1b shows partial side views of a body of a motor vehicle, for example an electrically powered vehicle, with a floor structure according to the invention and with an energy storage device arranged below a vehicle floor, wherein respective energy absorption elements run within corresponding cavities of the lateral corresponding side sills and have a respective non-linear or curved length section in their length or between the front and rear end regions, wherein in Fig. 1a an inner partial shell of the respective side sill is shown, which is in Fig. 1b For the sake of clarity, the following has been omitted: Fig. 2a, 2b respective partial side views of the floor structure according to the Fig. 1a und 1b , whereby in Fig. 2a Furthermore, the respective cross members of the floor structure are recognizable, which run in the transverse direction of the vehicle between the side sills and are arranged in a central area above a floor panel and in the front and rear end areas below this floor panel, and wherein in Fig. 2b Furthermore, the course of the respective lateral energy absorption element is shown; Fig. 3 is a partial and schematic sectional view along a cutting plane running in the transverse direction or in the vertical direction of the vehicle through the floor structure according to the Fig. 1a bis 2b , wherein the arrangement of the corresponding energy absorption element within the laterally associated side sill is recognizable, as well as its support on the respective cross member towards the center of the vehicle; and Fig. 4 respective side views of the energy storage device below the vehicle floor of the floor structure analogous to the Fig. 2a und 2b , whereby different designs of the respective lateral energy absorption element are indicated.

[0021] In the Fig. 1a und 1b Each figure shows a partial side view of the body of a passenger car, which in this embodiment is electrically powered. Visible here is a floor structure 10 with a side sill 12 arranged on the corresponding side of the vehicle, of which in this case Fig. 1a Only an inner partial shell 14 is shown. This partial shell 14 belongs to a side wall 16 of the body, which also includes an A-pillar 18, a B-pillar 20 and a C-pillar 22.

[0022] In conjunction with Fig. 3 In a partial sectional view along a section plane running in the transverse direction (y-direction) and the vertical direction (z-direction) of the vehicle, it becomes apparent that an energy absorption element 28 is arranged within a respective cavity 24 of the laterally corresponding side sill 12, which is formed on one side by the partial shell 14 and on the other side by an outer shell 26. This energy absorption element 28 extends – as can be seen from Fig. 1a is recognizable - at least approximately over the entire length of the side sill 16 or of a vehicle floor 30, of which, in combination, the Fig. 1b and Fig. 3 A base plate 32 is visible, below which a storage housing 34 of an energy storage device 36 for the electric drive of the passenger car is arranged.

[0023] From the Fig. 2a und 2b , which essentially only show the vehicle floor 30 of the floor structure 10 with the storage housing 34 of the energy storage device 36 arranged below the floor plate 32, it can be seen that in a central area of ​​the floor structure 10, with respect to the longitudinal direction of the vehicle (x-direction), a plurality of cross members 38, 40, 42, 44, 46 are provided, all of which extend in the transverse direction of the vehicle (y-direction) and horizontally between the side sills 16 arranged on both sides of the vehicle and - as can be seen in particular from Fig. 3 It can be seen that it connects to the inner side of the partial shell 14 of the side sill 12.

[0024] In the area of ​​the rear cross member 46, the vehicle floor 30 transitions into a rear floor 49 at a step 48.

[0025] As furthermore, particularly from the Fig. 1b and 2aAs can be seen, a crossbeam 50 is arranged on the front side of the storage housing 34 of the energy storage device 36. This crossbeam also runs horizontally and in the transverse direction (y-direction) of the vehicle and is located below the floor plate 32. More precisely, the crossbeam 50 is located below a transition area of ​​the floor plate 32 to a pedal floor 52 and from there into an end wall 54, which divides the passenger compartment of the vehicle from a front structure.

[0026] A cross member 56 is also provided in the rear area, which is arranged below the rear floor 49 or below an imaginary extension of the floor plate 32. In this area, the storage housing 34 can be recessed to accommodate the cross member 56.

[0027] As can be seen particularly from the Fig. 1a, 1b and 2bAs can be seen, the respective energy absorption element 28 arranged within the cavity 24 does not have a straight, linear profile, but rather, in this embodiment, is non-linear in its length and comprises a total of three length sections: a central section 62, which connects to a respective end section 58 or 60. While the central section 62 is straight and runs parallel to the longitudinal axis of the vehicle, the front and rear end sections 58 and 60 run at an angle to the straight central section 62 of the energy absorption element. The two end sections 58 and 60 can be formed separately from the central section 62 or integrally with it and shaped accordingly.For example, it is conceivable to design the energy absorption element 28 as a single- or multi-chamber extruded profile, with the respective end regions 58, 60 attached to the central region 62, or alternatively, the extruded profile is formed in one piece and correspondingly shaped at the front and rear. The non-linear length regions or end regions 58, 60 relative to the central region 62 are, for example, designed as arcuate curved sections or as linear regions in themselves, arranged at a corresponding angle to the central region 62 and connected to each other via non-linear transition regions 70.1 and 70.2. These transition regions 70.1 and 70.2 are therefore the points on the energy absorption element 28 where it acquires a non-linear length profile and the end regions 58, 60 are inclined relative to the middle region 62 such that the longitudinal center axes of the end regions 58, 60 do not align with the longitudinal center axis of the straight middle region 62, but run at an angle greater than 0° to it.

[0028] It is also included within the scope of the invention that the energy absorption elements 28 can be made of a material other than a metal suitable for extrusion. In particular, plastic components or hybrid components with metals and plastics, or joined steel roll profiles, are also conceivable.

[0029] The central area 62 of the energy absorption element 28 on the respective side of the vehicle extends at least substantially to the level of the cross members 38 to 46 in the vehicle's vertical direction (z-direction) above the floor plate 32 and thus also above the storage housing 34 of the energy storage device 36. This has the advantage that the central area 62 of the energy absorption element 28 can have a low height HE (Fig. 3b), which essentially corresponds to the height of the respective cross members 38 to 46, and yet is optimally supported towards the vehicle's center due to its vertical position in the vehicle's vertical direction (z-direction) in overlap with the respective cross members 38 or 46, when a Fig. 3 The depicted barrier 64, or a vehicle or the like, impacts the ground structure with a force 66 in a side impact. Due to the height of the energy absorption element 28, and in particular its central region 62, being essentially above the energy storage device 36, the installation of crossbeams within the storage housing 34 can be omitted. This results in significant savings in installation space and weight on the one hand, and a simpler design of the storage housing 34 on the other. Nevertheless, optimal support of the respective energy absorption element 28 in the transverse direction (y-direction) of the vehicle is ensured, thus guaranteeing optimal side-impact protection.

[0030] As can be seen particularly from the Fig. 1b and 2bAs can be seen, the modified course of the end sections 58 and 60, achieved through the non-linear transition areas 70.1 and 70.2 compared to the central area 62, allows the end sections 58 and 60 to overlap with the respective crossbeams 50 and 56, respectively, located in the front and rear areas of the floor structure 10. In the front area of ​​the floor structure 10, this results in optimal support of the front end section 58 of the energy absorption element 28 on the crossbeam 50, which is located below the floor plate 32. Similarly, in the rear area of ​​the floor structure 10, optimal support is provided for the rear end section 60 of the energy absorption element 28, which also runs, at least substantially, above the energy storage device 36 in this area.

[0031] Especially in conjunction with Fig. 3 It is also evident that the height HS of the respective side sill 12 essentially corresponds to three times the height HE of the respective energy absorption element 28. The height HE of the energy absorption element 28 is therefore considerably less than the height HS of the corresponding side sill 12 within its cavity 24, which is located in the energy absorption element 28. In the present case, the energy absorption element 36 extends over approximately the entire width of the side sill 12 and is locally held within the cavity 24 of the side sill 12 by means of a corresponding sheet metal part 68, which runs essentially in the vehicle's vertical (z-direction) and longitudinal (x-direction) direction. The sheet metal part 68 thus serves to position and fix the energy absorption element 28 within the side sill 12.

[0032] In Fig. 4 are analogous to the Fig. 2a und 2b Further embodiments of the corresponding lateral energy absorption element 28 per vehicle side are recognizable in the respective side views. In particular, it becomes clear again from the two upper illustrations that, in particular, a respective front or rear end region 58, 60 preferably forms the non-linear length profile of the energy absorption element 28 with respect to the middle region 62 (this embodiment is not shown) or – as in the illustrated embodiments according to the upper and middle illustrations of the Figur 4 provided - that a respective front or rear linear end region 58, 60 are connected to the middle region 62 by non-linear transition regions 70.1 or 70.2, while the end regions 58, 60 in themselves again have a straight / linear length profile.

[0033] In Fig. 4The lower figure shows an embodiment of the energy absorption element 28, in which the central region 62 is multiply curved or provided with respective non-linear length ranges 70.1 to 70.6, while the length ranges 70 running between these non-linear length ranges 70.1 to 70.6 each have, or can have, a straight length. Thus, the respective length ranges or curvature ranges allow for an even more optimal adaptation of the energy absorption element 28 to the respective arrangement of the crossbeams 38 to 46 in the vehicle's vertical direction (z-direction in the vehicle coordinate system).

[0034] In summary, it is evident that the floor structure according to the invention enables the creation of a sill structure with associated energy absorption elements 28 that is optimized for cost, weight, and installation space. This structure, tailored to the contour of the vehicle floor 30 or the floor structure 10 as a whole, optimally protects the respective energy storage device 36 and improves occupant safety in the event of a side impact. Furthermore, the floor structure and the associated energy absorption elements 28 can be optimally adapted to different energy storage devices. Thus, the floor structure 10 can be adapted not only to an energy storage device 36 for an electric drive, but is also equally applicable, for example, to a fuel tank, such as for fuel cells.

[0035] In particular, additional crossbeam structures within the energy storage unit 36 ​​or the storage housing 34 can be avoided in vehicles with increased vehicle weight. The non-linear or curved design of the respective energy absorption element 28, at least in one longitudinal region, allows for the most complete possible support and overlap with the crossbeam structure above the energy storage unit 36.

[0036] Furthermore, a modular system can be created which can be used to upgrade the respective side sills 12 and their energy absorption elements 28 at the positions necessary for the protection of the respective energy storage device 36, particularly in the case of vehicles that are based on a common body platform but have to meet increased requirements compared to the basic vehicle with regard to vehicle mass, high-voltage safety (for example, protection of electrical components of electric vehicles), occupant safety or variations in dimensional concept (for example, wheelbases).This is achieved by adapting the energy absorption structure and its energy absorption elements 28 to the resulting, different positions of the crossbeam structures by varying the number and geometry of the non-linear curvature zones, thereby improving vehicle safety in the event of a side impact with an opposing vehicle / crash barrier 64 in a weight- and cost-optimized manner. For this purpose, the size and position of the support / overlap areas between the energy absorption structure and its energy absorption elements 28 and the crossbeam structure are optimized, thus preventing intrusion of the floor structure into the installation space of the energy storage unit 36 ​​during the impact.

[0037] In summary, it should be noted that, in connection with the present invention, an energy absorption element with at least one non-linear length section along its length is to be understood as an elongated profile component that does not have a straight longitudinal center axis, but is shaped or formed in such a way that at least two length sections are created whose longitudinal center axes are not aligned. In the case of straight length sections viewed individually, these are inclined to each other and form an angle between them. Alternatively, if one of these non-linear length sections is curved and its longitudinal center axis has a correspondingly curved shape, the non-linear length section is angled upwards or downwards from the linear length section according to its shape.It is important that the respective energy absorption element is shaped along its length in such a way that the energy absorption element is arranged in the transverse and vertical directions of the vehicle in overlap, preferably at least partial overlap, in particular full overlap, with cross members arranged in the floor area of ​​the body, which in turn are arranged at different height levels with respect to an imaginary horizontal, for example a roadway located under the vehicle.

Claims

1. Floor structure (10) for a passenger car, comprising respective side skirts (12) which delimit at least one cavity (24), are laterally connected to a vehicle floor (30) and between which a plurality of cross members (38 - 46, 50, 56) extend, and comprising respective energy absorption elements (28) which extend along the associated side skirt (12) and extend at least approximately over the entire length of the side skirt (12) characterized in that the cross members (38 - 46, 50, 56) are arranged, along the extent of the floor structure in the longitudinal direction of the vehicle, at different heights relative to the vertical direction of the vehicle, and in that the energy absorption elements (28) have at least one non-linear longitudinal region (58; 60; 70.1 to 70.6) in their longitudinal extent, which is designed such that the relevant energy absorption element (28) is arranged in at least partial overlap with the cross members (38 - 46, 50, 56) in the transverse direction of the vehicle and vertical direction of the vehicle.

2. Floor structure (10) according to claim 1, characterized in that the energy absorption elements (28) are arranged within the cavity (24) of the associated side skirt (12).

3. Floor structure (10) according to claim 1 or claim 2, characterized in that the energy absorption elements (28), in their longitudinal extent between their central region (62) and a front and / or rear end region (58, 60) that is at least indirectly connected to the central region, have at least a non-linear transition region (70.1 to 70.6) or a linear transition region (70.1 to 70.6) that extends obliquely to the longitudinal center axis of the central region (62).

4. Floor structure according to claim 1 or claim 2, characterized in that a front and / or rear end region (58, 60) of the energy absorption elements is designed as a non-linear longitudinal region relative to a central region (62).

5. Floor structure (10) according to any of the preceding claims, characterized in that the front and / or rear end region (58, 60) of the energy absorption elements (28) is lowered relative to the central region (62).

6. Floor structure (10) according to any of the preceding claims, characterized in that the energy absorption elements (28) in the central region (62) extend at least substantially at the level of respective cross members (38 to 46) extending above a floor plate (32) of the vehicle floor (30).

7. Floor structure (10) according to any of claims 3 to 5, characterized in that the energy absorption elements (28), together with their relevant front end region (58), extend at the level of a cross member (50) extending below the floor plate (32) of the vehicle floor (30).

8. Floor structure (10) according to any of claims 3 to 6, characterized in that the energy absorption elements (28), together with their relevant rear end region (60), extend at the level of a cross member (56) extending below the vehicle floor (30).

9. Floor structure (10) according to any of the preceding claims, characterized in that the energy absorption elements (28) in the central region (62) extend at least substantially above an energy storage device (34) arranged below the vehicle floor (30) and between the side skirts (12).

10. Floor structure (10) according to any of the preceding claims, characterized in that the height (HS) of the side skirts (12) corresponds at least substantially to three times the height (HE) of the energy absorption elements (28).

11. Modular system for a body of a motor vehicle comprising at least an electrically operable variant and an internal combustion engine-operable variant and / or at least two electrically operable variants which each have different energy stores, the system comprising respective cross-variant side skirts of a floor structure according to any of claims 1 to 10, which have a hollow profile at least in a relevant longitudinal region, characterized in that an associated variant-specific energy absorption element is provided along the associated side skirt, which element, at least in the case of the electrically operable variant of the motor vehicle, has at least one non-linear longitudinal region (58; 60; 70.1 to 70.6) in its longitudinal extent, and in that in at least one further variant of the motor vehicle, a variant-specific energy absorption element is associated with the side skirts, which element can also have a non-linear longitudinal region (58; 60; 70.1 to 70.6).