Motor vehicle body shell

Abstract

The invention relates to a motor vehicle body shell (1) with an integrated battery frame (2) for an underfloor battery (10). To functionally improve the vehicle body structure (1), the battery frame (2) has angled sliding surfaces (31,32) at the front, each facing a front wheel and combined with a crash box, which in a crash event enables load support of the front wheel in a longitudinal direction of the vehicle up to a defined load and which deforms when this load is exceeded in such a way that the front wheel can slide laterally outwards.

Description

[0001] The invention relates to a motor vehicle body shell with an integrated battery frame for an underfloor battery.

[0002] German patent application DE 10 2018 113 812 A1 discloses a motor vehicle body, also referred to as a box body, with a battery box for accommodating a traction battery. American patent application US 2003 / 0141712 A1 discloses a motor vehicle front body assembly with front wheels and front wheel crossmembers, wherein the front wheel crossmembers have energy-absorbing elements that are deformable when subjected to a collision load.German patent application DE 10 2012 025 335 A1 discloses a crash structure for a vehicle with a deformation element arranged in the area of ​​a wheel housing between a wheel and a sill structure, wherein the deformation element releases movement of the wheel outside of an accident situation and at least partially dissipates crash energy of the wheel penetrating towards a footwell of the vehicle in an accident situation, wherein a load distributor couples the deformation element to an A-pillar and / or a roof frame, wherein the deformation element has a slope which is oriented towards the wheel in such a way that the wheel can be dissipated outwards in the accident situation, wherein the deformation element is wedge-shaped.German patent application DE 10 2013 101 697 A1 discloses a motor vehicle support structure comprising an A-pillar, a front wheel, and a sliding surface for the front wheel, wherein the sliding surface for the front wheel is formed on the A-pillar and is angled such that, in a frontal crash relative to the front wheel, the front wheel slides outwards along the sliding surface, wherein a front A-pillar flange area is arranged towards the center of the vehicle, and wherein the front bulkhead is combined with a cross member. FR 3 081 799 A1 discloses a protective device for a frame, which includes deflection means.

[0003] The object of the invention is to functionally improve a motor vehicle body shell with an integrated battery frame for an underfloor battery.

[0004] The problem is solved in a vehicle body shell with an integrated battery frame for an underfloor battery by providing the battery frame with angled sliding surfaces at the front, each facing a front wheel and combined with a crash box. In a crash, this crash box provides load support for the front wheel in a longitudinal direction up to a defined load. If this load is exceeded, the crash box deforms in such a way that the front wheel can slide laterally outwards. The underfloor battery is preferably a high-voltage battery, also known as a traction battery or high-voltage traction battery. Advantageously, the underfloor battery comprises several battery modules combined in a common battery system. The terms front, rear, top, bottom, transverse, and longitudinal refer to a three-dimensional Cartesian coordinate system.A vehicle's longitudinal direction is also referred to as the x-direction. A vehicle's transverse direction is also referred to as the y-direction. A vehicle's vertical direction is also referred to as the z-direction. The terms front and rear refer to the vehicle's longitudinal direction. The terms top and bottom refer to the vehicle's vertical direction. The vehicle body shell is preferably a box-type body shell, as disclosed in German patent application DE 10 2018 113 812 A1. The underfloor battery is advantageously positioned in the center of the floor within the battery frame. The crash test may involve a so-called small-overlap crash. A small-overlap crash is, in particular, a frontal collision with minimal overlap. In a corresponding small-overlap crash test, a front tire is, for example, pushed against a rocker panel. In this case, it is advantageous if the front tire can slide outwards along the rocker panel.Another crash scenario involves the so-called OBD crash. The letters OBD stand for Offset Deformable Barrier. In an OBD crash, the front tire is also pushed against the rocker panel. In this load case, however, as much force as possible should be supported by a locking front wheel against the rocker panel. Premature slippage of the tire should be prevented. In the vehicle body structure under consideration, the angled slip surfaces are advantageously provided on the battery frame. This protects the underfloor battery located within the battery frame in the event of a crash. The battery frame preferably comprises at least two longitudinal members and two transverse members. The crash boxes are advantageously positioned at the front wheels in such a way that they ensure load support of the front wheels in the longitudinal direction of the vehicle up to the defined load.This enables the desired capture, holding, and support of the front wheels in the event of a crash, particularly an OBD crash. If the defined load is exceeded, the crash box deforms in such a way that it forms a sliding plane, essentially approximating the angled sliding surface on the battery frame. This allows the front wheel to slide and be pushed out as desired in a crash, especially a small-overlap crash. The resulting vehicle body shell allows for an increase in the battery installation space in the longitudinal direction of the vehicle. Furthermore, the resulting vehicle body shell enables weight and cost savings in manufacturing.

[0005] It is further according to the invention that the battery frame has bends in corner areas to form the angled sliding surfaces. Viewed from a top view, the battery frame essentially has the shape of a rectangle. The angled sliding surfaces represent chamfered corners on the battery frame. In this way, the angled sliding surfaces can be manufactured using simple means.

[0006] Furthermore, according to the invention, bends are formed on a front cross member, which is attached to two longitudinal members. These longitudinal members, together with the front cross member and a rear cross member, form the battery frame. The longitudinal and transverse members of the battery frame can be designed as extruded profiles. Alternatively, the longitudinal and transverse members of the battery frame can be designed as joined sheet metal. In this way, a stable battery frame with high functionality can be realized using simple manufacturing methods.

[0007] Another preferred embodiment of the vehicle body shell is characterized in that the longitudinal members of the vehicle body shell serve as sills. This offers the advantage that conventional sills can be omitted.

[0008] Another preferred embodiment of the vehicle body shell is characterized in that bends are formed on the rear crossmember to create rear sliding surfaces facing the rear wheels. This advantageously ensures safety even in a rear-end collision or when the vehicle is reversing at high speed.

[0009] Another preferred embodiment of the vehicle body shell is characterized in that the rear sliding surfaces are combined with crash boxes which, in the event of a crash, provide load support for the respective rear wheel up to a defined load and which deform when this load is exceeded in such a way that the respective rear wheel can slide laterally outwards. This further increases the protection of the underfloor battery within the battery frame.

[0010] Another preferred embodiment of the vehicle body-in-white is characterized in that a deformation space is provided between the underfloor battery and one or the rear crossmember. This further increases the protection of the underfloor battery within the battery frame.

[0011] Another preferred embodiment of the vehicle body-in-white is characterized by the fact that a deformation space is provided between the underfloor battery and the front crossmember. This further increases the protection of the underfloor battery within the battery frame.

[0012] Another preferred embodiment of the vehicle body shell is characterized in that at least one crash box is arranged in the deformation space. This further increases the protection of the underfloor battery within the battery frame.

[0013] Another preferred embodiment of the vehicle body shell is characterized in that the crash box comprises a sheet metal shell construction, an extruded profile, and / or a plastic box. According to one embodiment, the crash box is designed as a sheet metal shell construction made of an aluminum or steel alloy. According to another embodiment, the crash box is designed as an extruded profile made of an aluminum alloy. Depending on the desired crash load, one extrusion direction of the extruded profile extends in the longitudinal direction of the vehicle or perpendicular to the longitudinal direction of the vehicle. According to another embodiment, the crash box is designed as a plastic box. According to one variant, the plastic box is provided with ribbing. According to another variant, the plastic box is designed without ribbing. According to another variant, the plastic box is provided with fiber reinforcement.According to another variant, the plastic box is designed without fiber reinforcement. Further embodiments and variants of the crash box comprise a combination of at least two previously described embodiments and / or variants.

[0014] The invention further relates to a battery frame and / or a crash box for a previously described vehicle body shell. The battery frame and the crash boxes are available separately. Battery modules of the underfloor battery can advantageously be bolted to the battery frame, in particular to the longitudinal members of the battery frame, without an additional housing. The crash boxes can be designed as extruded profiles. An extrusion direction of the crash boxes designed as extruded profiles advantageously extends orthogonally to a driving surface. However, the crash boxes can also be designed as sheet metal constructions.

[0015] The invention may also relate to a motor vehicle with a previously described body-in-white. The motor vehicle is preferably a purely electric or partially electric motor vehicle.

[0016] Further advantages, features, and details of the invention will become apparent from the following description, in which various exemplary embodiments are described in detail with reference to the drawing. The drawing shows: Fig. 1 a schematic representation of the motor vehicle body shell with a battery frame in a bottom view; Fig. 2 the battery frame Fig. 1 with crash boxes assigned to two front wheels and two rear wheels; and Fig. 3 a perspective view of the battery frame alone.

[0017] In Fig. Figure 1 shows a vehicle body shell 1 in a bottom view. The vehicle body shell 1, also referred to as the car body, is designed as a box-type body shell. The box-type body shell is designed in the same or a similar way as the box-type body shell described in German patent application DE 10 2018 113 812 A1.

[0018] The vehicle body shell 1 comprises a battery frame 2, which serves to accommodate an underfloor battery 10; 20. The underfloor battery 10; 20 is arranged in the battery frame 2 in an underbody area of ​​the vehicle body shell 1.

[0019] In Fig. On the left, a front end 3 of the vehicle body shell 1 is indicated. An arrow 5 indicates the forward direction of travel of a vehicle equipped with the vehicle body shell 1. Fig. 1 on the right is a hedge end 4 of the motor vehicle body shell 1 indicated.

[0020] The underfloor battery 10 is a lithium-ion-based high-voltage battery comprising several battery modules 11 to 16; 21 to 26. The battery modules 11 to 16; 21 to 26 constitute a battery system located in the center of the vehicle body shell.

[0021] The battery frame 2 surrounds the underfloor battery 10; 20 at the front, rear, and sides. For this purpose, the battery frame 2 comprises two longitudinal members 6, 7, which are stably connected to each other by a front cross member 8 and a rear cross member 9.

[0022] The longitudinal members 6, 7 of the battery frame 2 extend in a longitudinal direction of the vehicle, also referred to as the x-direction. The transverse members 8, 9 extend in a transverse direction of the vehicle, also referred to as the y-direction.

[0023] The outer end sections of the crossbeams 8, 9 are angled away from the central sections of the crossbeams 8, 9. This results in sliding surfaces 31, 32; 33, 34 on the crossbeams 8, 9.

[0024] The sliding surfaces 31, 32 on the front crossbeam 8 are also referred to as front sliding surfaces 31, 32. The sliding surfaces 33, 34 on the rear crossbeam 9 are also referred to as rear sliding surfaces 33, 34.

[0025] The front sliding surfaces 31, 32 are arranged at an obtuse angle to the central region of the front cross member 8. The obtuse angle is, for example, 145 degrees. The rear sliding surfaces 33, 34 are arranged at an obtuse angle to the rear cross member 9. The obtuse angle is, for example, 140 degrees. A preferred range for the obtuse angles between the sliding surfaces 31 to 34 and the cross members 8, 9 lies between 120 and 160 degrees.

[0026] In Fig. 1. The battery modules 11 to 16 are arranged longitudinally. The battery modules 11 to 16 can be arranged in an additional box. Alternatively, the battery modules 11 to 16 can be attached to one another. The battery modules 11 and 16 are advantageously rigidly connected to the longitudinal beams 6, 7 of the battery frame 2.

[0027] The battery modules 21 to 26 in Fig. The battery modules 21 to 26 are arranged transversely to the vehicle. Advantageously, they are attached to the longitudinal members 6, 7 of the battery frame 2. This eliminates the need for an additional housing for the battery modules 21 to 26.

[0028] In Fig. 2 is the battery frame 2 of the vehicle body shell made of Fig. Figure 1 shows a bottom view with schematically indicated front wheels 27, 28 and rear wheels 29, 30. To protect the underfloor battery 10; 20, the battery frame 2 is combined with crash boxes 35 to 38.

[0029] Crash boxes 35 and 36 are assigned to the front skid plates 31 and 32 and are therefore also referred to as front crash boxes 35 and 36. Crash boxes 37 and 38 are assigned to the rear skid plates 33 and 34 and are therefore also referred to as rear crash boxes 37 and 38.

[0030] Crash boxes 35 to 38 serve to protect the underfloor battery 10; 20 within the battery frame 2 in various crash scenarios. These crash scenarios primarily involve the so-called OBD crash and the so-called small-overlap crash. These crash scenarios are described in advance.

[0031] The front crash boxes 35, 36 are each arranged in a projection of the associated front tire 27, 28 in the direction of travel. The crash boxes 35, 36 are designed such that, in the event of an OBD crash under low load, they support the force of the respective front wheel 27, 28 against the front crossmember 8 of the battery frame 2. The load is transferred via the front crossmember 8 into the longitudinal members 6, 7 of the battery frame 2, which form the sills.

[0032] When a defined load is exceeded, the crash boxes 35, 36 deform in such a way that the deformed crash box 35, 36 forms a sliding plane for the respective front wheel 27, 28. This sliding plane essentially has the shape of the front sliding surface 31, 32 on the front cross member 8.

[0033] The rear crash boxes 37, 38, in combination with the rear skid plates 33, 34, perform the same function in conjunction with the rear wheels 29, 30.

[0034] In Fig. Figure 3 shows the battery frame 2 with the sliding surfaces 31 to 34 on its own. The sliding surfaces 31 to 34 are advantageously realized on the crossbeams 8, 9 by bends 45 to 48. This significantly simplifies the manufacture of the battery frame 2 with the sliding surfaces 31 to 34.

[0035] In Fig. Figure 2 further shows that a deformation space 39; 40 is provided both between the front crossmember 8 and the underfloor battery 20 and between the rear crossmember 9 and the underfloor battery 20. This further improves the protection of the underfloor battery 20 in the event of a crash.

[0036] Additional crash boxes 41 and 42 are arranged in the front deformation space 39. The front crash box 41 is arranged diagonally offset from the front crash box 35. The front crash box 42 is arranged diagonally offset from the front crash box 36. The front cross member 8 is positioned between the diagonally offset crash boxes 41 and 35, and 42 and 36, respectively.

[0037] A crash box 43 is arranged in the rear deformation space 40. The crash box 43 is positioned centrally in the longitudinal direction of the vehicle between the underfloor battery 20 and the rear cross member 9 of the battery frame 2. Reference sign 1 Motor vehicle body shell 2 battery frames 3 Front end 4 Hedge ends 5 Arrow 6 longitudinal beams 7 longitudinal beams 8 front crossmember 9 rear crossmember 10 Underfloor battery 11 Battery module 12 Battery module 13 Battery module 14 Battery module 15 battery module 16 battery module 20 Underfloor battery 21 Battery module 22 Battery module 23 Battery module 24 battery module 25 battery module 26 battery module 27" front wheel 28" front wheel 29" rear wheel 30 rear wheel 31 front sliding surface 32 front sliding surface 33 rear skid plate 34 rear skid plate 35 Crashbox 36 Crashbox 37 Crashbox 38 Crashbox 39 front deformation space 30 rear deformation space 41 Crashbox 42 Crashbox 43 Crashbox 45 bend 46 bend 47 bend 48 bend

Claims

[1] Motor vehicle body shell (1) with an integrated battery frame (2) for an underfloor battery (10;20), characterized by , that the battery frame (2) has angled sliding surfaces (31, 32) at the front, each facing a front wheel (27, 28) and combined with a crash box (35, 36) which, in the event of a crash, enables load support of the front wheel (27, 28) in a longitudinal direction of the vehicle up to a defined load and which, if this load is exceeded, deforms in such a way that the front wheel (27, 28) can slide laterally outwards, wherein the battery frame (2) has bends (45,46) in corner areas to represent the angled sliding surfaces (31,32) and the bends (45,46) are formed on a front cross member (8) which is attached to two longitudinal members (6,7) which together with the front cross member (8) and a rear cross member (9) form the battery frame (2). [2] Motor vehicle body shell according to claim 1, characterized by , that the longitudinal members (6,7) on the motor vehicle body shell (1) represent sills. [3] Motor vehicle body shell according to claim 1 or 2, characterized by , that bends (47,48) are formed on the rear cross member (9) to represent rear sliding surfaces (33,34) facing the rear wheels (29,30). [4] Motor vehicle body shell according to claim 3, characterized by , that the rear sliding surfaces (33,34) are combined with crash boxes (37,38) which in a crash situation enable load support of the respective rear wheel (29,30) up to a defined load and which deform in such a way that the respective rear wheel (29,30) can slide laterally outwards if this load is exceeded. [5] Motor vehicle body shell according to any one of the preceding claims, characterized by , that a deformation space (40) is provided between the underfloor battery (10;20) and a rear cross member (9). [6] Motor vehicle body shell according to any one of the preceding claims, characterized by , that a deformation space (39) is provided between the underfloor battery (10;20) and the front cross member (8). [7] Motor vehicle body shell according to claim 5 and / or 6, characterized by , that at least one crash box (41,42;43) is arranged in the deformation space (39,40). [8] Motor vehicle body shell according to any one of the preceding claims, characterized by , that the crash box (35,36;37,38;41,42;43) comprises a sheet metal shell construction, an extruded profile and / or a plastic box.

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