Vehicle bodyshell and method for assembling and disassembling the vehicle bodyshell

Abstract

The invention relates to a vehicle bodyshell (1) comprising a body (2) which forms a frame (7), said frame (7) enclosing a chamber (8), at least one support (3) which is arranged within the chamber (8), and a traction battery (4) which is connected to the at least one support (3). The vehicle bodyshell according to the invention is characterized in that the at least one support (3) extends through the chamber (8) and is connected to the frame (7), the support (3) is connected to the rest of the body (2) via releasable securing means (6), and the traction battery (4) is connected to the at least one support (3) by means of an adhesive (5).

Description

[0001] Vehicle bodyshell and processes for assembly and disassembly of the vehicle bodyshell

[0002] The invention relates to a vehicle body shell according to the preamble of claim 1 and a corresponding method for assembling and disassembling the vehicle body shell.

[0003] The proportion of vehicles with at least partially electrified powertrains in the road network is steadily increasing. Such vehicles have an electric drive unit that is powered by electrical energy stored in an electrical energy storage unit. This type of electrical energy storage unit is also known as a traction battery.

[0004] The integration of traction batteries into the vehicle structure is challenging. A wide range of requirements must be met. For example, traction batteries must be securely and reliably connected to the respective vehicle structure. Adequate crash safety must be ensured. The available installation space should be used optimally. In the event of damage or a defect, it may be necessary to replace individual battery cells or even the entire traction battery. Appropriate measures must therefore be taken to enable easy maintenance of the traction battery. Installation tolerances of the traction battery in the vehicle body reduce the design flexibility for the construction of load-bearing body elements.

[0005] A traction battery is usually bolted to the vehicle body. A battery housing has appropriate holes or threads for this purpose. The respective screws can then be passed through the holes in the battery housing and bolted to the body, or through corresponding holes in the body and bolted to the battery housing. Special mounting profiles can also be attached to the battery housing to create the screw connection. When installing and removing the traction battery, these profiles are fixed to the battery housing and move accordingly with the traction battery. Appropriate installation tolerances must therefore also be maintained here. In addition, the geometry of the traction battery, or the respective connecting components, must be adapted for different vehicle series or models.This high variety of variants results in additional costs and effort in production.

[0006] A vehicle with an electrical energy storage unit is known, for example, from the generic document WO 2023 / 072807 A1. This document describes a traction battery that functions as the underbody of a vehicle. The traction battery has a lateral frame that absorbs forces in the event of an accident and guides them around the cells of the traction battery. The frame is bolted directly to the vehicle body to secure the traction battery. Here, too, sufficient installation tolerances must be ensured, which limits the design flexibility in the construction of the elements to be connected.

[0007] DE 102016219242 A1 discloses a motor vehicle with a floor assembly, to the underside of which an energy storage device is to be attached. For this purpose, the energy storage device is operatively connected to the floor assembly at its outer edges by means of fastening elements formed by screws. Furthermore, a number of retaining brackets are provided in the central area of ​​the floor assembly, bolted to these brackets, to which the energy storage device is additionally glued. Strut elements are also used as an alternative to the retaining brackets. Disassembling the energy storage device is complex because the adhesive bonds must be removed beforehand.

[0008] Similar retaining brackets to those known from DE 102016219242 A1 are also disclosed in DE 102017206650 A1, which are part of a fastening arrangement for securing a vehicle battery within a floor-side body recess. The retaining brackets are screwed to the body from the vehicle interior. When the vehicle battery is inserted into the body recess, adhesive is applied to the contact areas between the vehicle battery and the retaining brackets to form a material bond. Furthermore, the vehicle battery is screwed to the body at the edges with a number of screw connections. To remove the vehicle battery, the screw connection of the retaining brackets must be loosened from the vehicle interior, which is correspondingly complex due to the typically existing interior.

[0009] The present invention is based on the object of providing an improved vehicle body shell which allows easy removal and installation of traction batteries and allows the provision of a high variety of variants for different vehicle models with little effort.

[0010] According to the invention, this object is achieved by a vehicle body shell having the features of claim 1, by a method for assembling the vehicle body shell having the features of claim 5, and by a method for disassembling the vehicle body shell having the features of claim 6. Advantageous embodiments and further developments emerge from the respective dependent claims.

[0011] A generic vehicle bodyshell, comprising a body forming a frame, wherein the frame encloses a space, at least one support arranged within the space, and a traction battery connected to the at least one support, is further developed according to the invention in that the at least one support extends through the space and is connected to the frame, that the support is connected to the rest of the body via releasable fastening means, and that the traction battery is connected to the at least one support by means of an adhesive. The support represents a separate component or assembly which is designed in multiple parts to the rest of the body, but thereby represents part of the body itself. This makes it possible to connect the support to the body separately, i.e. without attaching the traction battery to the support. The traction battery can then be attached to the support.During maintenance, it is thus possible to loosen the removable fastening elements and separate the traction battery, along with at least one carrier, from the body. This allows the traction battery to be easily removed from the body. This increases ease of maintenance. Furthermore, it is no longer necessary to adapt the geometry of the traction battery for different series of different vehicle types. Only the carrier(s) need to be designed differently. The corresponding adhesive points between the carrier and the traction battery can remain the same across all series. This means that fewer variants of traction batteries need to be maintained, which correspondingly reduces manufacturing effort and costs.

[0012] Typically, the terms "body shell" and "body" are used synonymously in vehicle manufacturing. For the purposes of the present invention, however, the term "vehicle body shell" refers to an assembly comprising the body and the traction battery. To manufacture a vehicle, additional components are connected to the vehicle body shell, such as the chassis, the electric drive unit, cables, fluid lines, and the like. The at least one support forms part of the body itself.

[0013] In this context, the traction battery can also be referred to as a so-called high-voltage battery and, in particular, has a higher voltage than a conventional automotive starter battery. Such a starter battery typically has a voltage in the range of 12 volts. A high-voltage battery has a higher voltage, in particular a voltage in the range of 400 volts or even 800 volts.

[0014] The adhesive used to bond the traction battery to the at least one carrier is, in particular, an adhesive with a comparatively high modulus of elasticity or shear modulus. This allows for compensation of positional tolerances during production without introducing excessive stress into the adhesive bond to be created. The adhesive is applied, in particular, over the entire contact surface between the traction battery and the at least one carrier. This allows for a highly resilient yet reliably holding adhesive bond.

[0015] The at least one support can consist of or comprise various materials. For example, the support comprises a metal such as aluminum or magnesium, an alloy such as steel, or even a lightweight material such as GRP or CFRP. The support can be designed as a solid profile or, preferably, as a hollow profile. With a suitable geometric design of the respective support as a hollow profile, highly resilient structures can be produced while being lightweight. The at least one support serves both as a suspension for the traction battery and to stiffen the body or absorb forces in the event of an accident. Since the support bears the weight of the comparatively heavy traction battery, the at least one support is therefore preferably geometrically designed such that it has high flexural rigidity in the direction of the bending moment imposed on the support by the traction battery.

[0016] Particularly preferably, the traction battery is the only component connected to a respective carrier. The at least one carrier is thus free of other vehicle components such as seats, cable harnesses, pipes, and the like. If the traction battery needs to be removed during subsequent maintenance, this is particularly easy to do, as no other components need to be removed, nor do any cable harnesses, hoses, or pipes need to be removed.

[0017] An advantageous development of the vehicle bodyshell according to the invention provides for more than one support. The multiple supports can be distributed across the base of the traction battery in a top view of the battery. This allows for uniform suspension of the traction battery. Increasing the number of supports also increases the area wettable with the adhesive, further improving the bonding of the traction battery to the body.

[0018] Preferably, at least one support is designed as a cross member. In the fully assembled vehicle, a cross member runs parallel to the vehicle's transverse axis. Typically, a vehicle such as a car has a smaller width than its length.

[0019] The cross members are correspondingly short, which counteracts strong deflection due to the weight of the traction battery.

[0020] According to a further advantageous embodiment of the vehicle bodyshell according to the invention, at least one support is designed as a longitudinal member. Corresponding longitudinal members can be provided in addition to or alternatively to said cross members. Through a suitable geometric design, the flexural rigidity of longitudinal members can be sufficiently increased so that even when the comparatively heavy traction battery is attached to a longitudinal member, the latter does not bend excessively. The provision of longitudinal members gives the designer more design freedom for the body design. This allows for more efficient use of available installation space.

[0021] Beams can also generally be angled, meaning they can be oriented in the direction of the vehicle's transverse and longitudinal axes. This further increases the designer's design freedom.

[0022] Because the body of the vehicle bodyshell according to the invention forms a frame, with at least one support extending within a space enclosed by the frame, corresponding supports can be integrated into the body even more easily. This allows for good accessibility from underneath the body during production. Furthermore, easily accessible, clearly defined suspension points for the supports can be provided on the frame.

[0023] A further advantageous embodiment of the vehicle bodyshell according to the invention further provides for detachable fastening means in the form of screws. Generally, all conceivable detachable connection techniques are suitable. However, screw connections in particular are characterized by their simplicity and high availability of the corresponding components. A screw connection therefore represents the preferred detachable connection technique. Screws can also be easily tightened and loosened, which minimizes the corresponding production and maintenance times. Screws can also be reused.

[0024] According to a further advantageous embodiment of the vehicle bodyshell according to the invention, at least one support extends in its direction of travel across the entire extent of the traction battery. If it is a cross member, the cross member extends in the direction of the vehicle's transverse axis across the entire width of the traction battery. If, however, it is a longitudinal member, the longitudinal member extends in the direction of the vehicle's longitudinal axis across the entire length of the traction battery. This further improves the connection of the traction battery to the corresponding support, since the weight of the traction battery is thus evenly distributed as a corresponding line load or area load. The respective adhesive connection holds accordingly more reliably.

[0025] A method according to the invention for assembling a vehicle body shell as described above comprises the following method steps:

[0026] - Providing a body;

[0027] - connecting the at least one support to the frame of the body by means of the detachable fastening means, in particular by means of screws;

[0028] - Providing the traction battery and applying the adhesive in a desired area on the carrier and / or the traction battery, wherein the desired area in the installed state lies in an overlap area of ​​the traction battery with the at least one carrier;

[0029] - Pressing the traction battery and carrier together with a contact force;

[0030] - Curing of the adhesive; and

[0031] - Removal of the contact pressure.

[0032] The method according to the invention allows for particularly simple assembly of the vehicle body shell. First, any supports are connected to the rest of the body. Then, the traction battery is glued to the supports. Since the supports are connected to the body without the traction battery, no installation tolerances of the traction battery on the respective supports need to be maintained, which further increases the design flexibility for the supports. This allows the supports to be designed with greater space efficiency. Furthermore, the supports can be positioned and aligned more easily relative to the rest of the body.

[0033] The carriers can be adapted to the respective vehicle model. The traction battery can be used for various vehicle models. Only the design of the target area can vary for different series, so that bonding with carriers of different geometric designs is possible. The adhesive only needs to be applied to different locations, which enables easy installation of different series. For this purpose, bonding can generally be carried out via the battery housing. If this is designed as a flat surface, no geometric changes to the traction battery are even necessary to adapt the traction battery to correspondingly differently designed carriers. This means that the adhesive can be applied to any location on the flat surface of the battery housing.

[0034] The contact pressure is maintained until the adhesive has cured. This allows for a particularly high-strength bond.

[0035] A method according to the invention for dismantling a vehicle body shell as described above comprises the following method steps:

[0036] - Loosening of the fastening means, in particular loosening of the screw connection; and

[0037] - Removal of the traction battery and all attached supports from the body.

[0038] As already explained, the vehicle body shell according to the invention can thus be disassembled or taken apart particularly easily. This allows for easy and quick access to the traction battery during maintenance, should individual battery cells or battery modules need to be replaced, or even the entire traction battery needs to be replaced. The traction battery, along with the carriers attached to it, is removed from the body. The traction battery can then be moved to a location where it is easily accessible. After maintenance, the traction battery, along with the carriers attached to it, can be reinserted into the body.

[0039] If, however, the entire traction battery needs to be replaced, the adhesive bond between the traction battery and at least one carrier can be removed, preferably after removing the traction battery from the body. The carrier(s) can then be reinserted separately into the body, and a new traction battery can be provided and bonded to the carriers connected to the body, as previously described. Optionally, any adhesive residue can be removed from the carriers and the traction battery beforehand.

[0040] Further advantageous embodiments of the vehicle body shell according to the invention and of the method according to the invention for assembling and disassembling the vehicle body shell also emerge from the exemplary embodiments, which are described in more detail below with reference to the drawings.

[0041] Fig. 1 is a schematic exploded view of a vehicle body shell according to the invention;

[0042] Fig. 2 is a schematic flow chart of a method according to the invention for assembling the vehicle body shell according to the invention; and

[0043] Fig. 3 shows a schematic flow chart of a method according to the invention for dismantling the vehicle body shell according to the invention.

[0044] Figure 1 shows an exploded view of a vehicle body shell 1 according to the invention. This comprises a body 2 with at least one support 3 and a traction battery 4 connected or connectable to the at least one support 3. The traction battery 4 is connected to the at least one support 3 by means of an adhesive 5 shown in the following figures. The at least one support 3, in turn, is connected to the remaining body 2 via detachable fastening means 6, for example screws. In Figure 1, the detachable fastening means 6 are shown in an unassembled state.

[0045] Preferably, the body 2 forms a frame 7, which encloses a space 8. The support(s) 3 are then connected to the frame 7 and extend through the space 8. Preferably, the frame 7 and the support(s) 3 are designed such that the supports 3 can be removed particularly easily downwards from the space 8.

[0046] Particularly preferably, the vehicle body shell 1 comprises more than one support 3. Each support 3 can run parallel to the vehicle's longitudinal axis 9 or parallel to the vehicle's transverse axis 10. In general, supports 3 can also run diagonally.

[0047] Each support 3 can have any shape, for example, an I-shaped or T-shaped shape in a plan view. Any cross-sectional shape is also possible, with hollow profiles with a comparatively high area moment of inertia being the preferred choice, in particular, to increase the flexural rigidity in the direction of the bending moment imposed on the respective support 3 by the weight of the traction battery 4.

[0048] Particularly preferably, at least one carrier 3 extends in its direction of travel over the entire extent of the traction battery 4 in the direction of travel. The respective carrier 3 thus preferably rests on the traction battery 4 over the entire width b or the entire length l via the adhesive 5.

[0049] Figure 2 shows the sequence of an assembly method according to the invention for producing the vehicle body shell 1. In a step 201, the body 2 is provided and the at least one carrier 3 is connected to the body 2 by means of the detachable fastening means 6, in particular in the form of screws.

[0050] In a step 202, the traction battery 4 is provided and the adhesive 5 is applied to the carrier 3 and / or the traction battery 4 in a desired area, wherein the desired area, in the installed state, lies in an overlap region of the traction battery 4 with the at least one carrier 3. In the exemplary embodiment shown in Figure 2, the adhesive 5 was applied to the underside of the respective carriers 3. The adhesive 5 is distributed over as large an area as possible in order to achieve a large wetted surface and thus a strong connection of the traction battery 4 to the respective carrier 3. However, some areas of a carrier 3, for example the T-shaped carrier 3 as shown, can also remain free of adhesive 5.

[0051] In a step 203, the traction battery 4 and the carriers 3 are pressed together with a contact force F. The process waits until the adhesive 5 hardens and then the contact force F is removed.

[0052] Figure 3 shows the sequence of a method according to the invention for dismantling the vehicle body shell 1. First, in a step 301, the fastening means 6 are released.

[0053] Subsequently, in a step 302, the traction battery 4 with the attached supports 3 is removed from the body 2, for example, by moving the traction battery 4 downwards or by lifting the remaining body 2 upwards. Maintenance of the traction battery is now easily possible due to the comparatively good accessibility. However, if the traction battery 4 is to be completely replaced, the optional step 303 could be performed. In step 303, the adhesive bond between the traction battery 4 and the supports 3 is released. This allows the supports 3 to be removed from the traction battery 4. Any adhesive residue can be removed. A new traction battery 4 can now be provided.

[0054] Reassembly then proceeds as described in Figure 2. First, the supports 3 are reinserted into the body 2 and connected to it using the fasteners 6. A new adhesive 5 is then applied, and the traction battery 4 is pressed onto the supports 3 using the adhesive 5.

[0055] The assembly and disassembly of the traction battery 4 with the body 2 can be repeated as often as desired. Since it is particularly preferred that no other vehicle components such as cables, hoses, pipes, or the like are attached to the supports 3, the maintenance or assembly time can be reduced even further, since the corresponding components can remain in the vehicle. Vehicle-series-specific supports 3 can be used, which can be connected to the same traction battery 4 regardless of their geometry. Thus, fewer geometrically specially adapted components need to be kept in stock in order to provide a high variety of variants. In the event of maintenance, it may be sufficient to loosen detachable fasteners instead of separating adhesive seams, which in particular shortens the required repair time.

Claims

Patent claims 1. Vehicle body shell (1), comprising a body (2) forming a frame (7), the frame (7) enclosing a space (8), at least one support (3) arranged within the space (8) and a traction battery (4) connected to the at least one support (3), characterized in that - that the at least one support (3) extends through the space (8) and is connected to the frame (7), - that the support (3) is connected to the rest of the body (2) via detachable fastening means (6), and - that the traction battery (4) is connected to the at least one carrier (3) by means of an adhesive (5).

2. Vehicle body shell (1) according to claim 1, characterized in that the at least one support (3) extends between side sills of the body (2) and is connected to them.

3. Vehicle body shell (1) according to claim 1 or 2, characterized in that the at least one support (3) is designed as a longitudinal support.

4. Vehicle body shell (1) according to one of claims 1 to 3, characterized in that at least one support (3) extends in its direction of extension over the complete extent of the traction battery (4) in the direction of extension.

5. Method for assembling a vehicle body shell (1) according to one of claims 1 to 4, characterized by the following method steps: - Providing a body (2); - Connecting the at least one support (3) to the frame (7) of the body (2) by means of the detachable fastening means (6); - Providing the traction battery (4) and applying the adhesive (5) in a desired area on the carrier (3) and / or the traction battery (4), wherein the desired area in the installed state lies in an overlap area of ​​the traction battery (4) with the at least one carrier (3); - pressing the traction battery (4) and the carrier (3) together with a contact force (F); - curing of the adhesive (5); and - Removal of the contact pressure (F).

6. Method for dismantling a vehicle body shell (1) according to one of claims 1 to 4, characterized by the following method steps: - loosening the fastening means (6); and - Removal of the traction battery (4) with all attached supports (3) from the body (2).

7. The method according to claim 6, characterized in that after removal of the traction battery (4) from the body (2), the adhesive (5) between the traction battery (4) and the at least one carrier (3) is dissolved.

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