Rear cross member for a ground vehicle, adapted to different motor assemblies
Patent Information
- Application Number
- EP2023751673
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-08-10
- Filing Date
- 2023-07-10
- Publication Date
- 2025-06-18
AI Technical Summary
Current rear crossmembers for land vehicles require different lower walls based on engine types, leading to increased diversity and complexity in production, inventory management, and costs due to the need for multiple stamping tools and hole closure processes.
A universal rear crossmember design featuring a lower wall that can accommodate either a fuel tank fixing part or internal spars, with adaptable reinforcement stampings and hole configurations for screwing or welding, allowing a single tool to produce compatible parts for various engines.
This design reduces production costs, simplifies inventory management, and decreases assembly time by enabling the use of a single stamping tool and minimizing unnecessary hole creation, thereby lowering overall vehicle costs and complexity.
Smart Images
Figure 1.1
Abstract
Description
DESCRIPTION TITLE: REAR CROSSMEMBER OF LAND VEHICLE, SUITABLE FOR DIFFERENT ENGINES Technical field of the invention
[0001] The present invention claims priority from French application 2208232 filed on August 10, 2022, the content of which (text, drawings and claims) is incorporated herein by reference. The invention relates to land vehicles comprising a structure comprising a rear cross member to which at least one element (possibly structural) must be secured. State of the art
[0002] Some vehicles, usually of the automobile type, include a structure (or platform) comprising a rear floor located in front of a load floor, and a rear cross member (sometimes called a "cross member closure") fixedly secured to the rear floor and the load floor. The rear floor generally supports the rear seat of the vehicle and extends a heel board of the structure rearwardly, and the load floor generally partially delimits the rear trunk of the vehicle.
[0003] As is known to those skilled in the art, the rear crossmember comprises a lower wall (facing the ground) which serves as an anchoring (or securing) zone for at least one element of the vehicle which depends on the latter's engine. Indeed, depending on the powertrain (or GMP) which equips the vehicle, the lower wall of the rear crossmember serves as an anchoring zone for at least one part for fixing a fuel tank (in the case of a thermal or hybrid GMP) or for two internal side members of the structure (in the case of an electric GMP). It is recalled that these two internal side members are generally used to reinforce the structure and allow the fixing of a rear part of a main (or traction) battery providing electrical energy for an electric prime mover of the GMP.
[0004] Currently, rear cross members are used with lower walls that differ depending on the engine. More specifically, we use:
[0005] - either a first lower wall specifically adapted to the securing of a single part for fixing a fuel tank when the GMP is purely thermal or hybrid and at the same time the rear axle is of the multi-link type,
[0006] - either a second lower wall specifically adapted to the joining of two fixing parts of a fuel tank when the GMP is hybrid and at the same time the rear axle is of the dynamic type,
[0007] - or a third lower wall specifically adapted to the joining of two internal side members for the support of the main (or traction) battery when the GMP is purely electric.
[0008] We are therefore forced to use three different stamping tools to produce the three different lower walls of the rear crossmembers and different hardware sub-assemblies, which increases diversity and complicates inventory management, and therefore increases vehicle costs. In addition, holes are also initially defined in the three different lower walls to allow the fastening parts to be screwed together, but when the fastening is done by welding (in the case of internal side members) we are forced to plug these holes when they are not in use to ensure the sealing of the rear crossmember, which takes time and further increases the diversity and complexity of inventory management, and therefore further increases vehicle costs.
[0009] The invention therefore aims in particular to improve the situation. Presentation of the invention
[0010] For this purpose, it proposes in particular a rear cross member, on the one hand, suitable for forming part of a structure of a land vehicle, this structure comprising a rear floor located in front of a load floor, and, on the other hand, suitable for being fixedly secured to the rear floor and to the load floor.
[0011] This rear cross member is characterized by the fact that it comprises a lower wall arranged in such a way as to allow the attachment of either at least one part for fixing a fuel tank of the land vehicle, or two internal side members of the structure.
[0012] Thanks to the invention, it is now possible to use the same lower wall for the rear cross members of vehicles that can have several different engines, which reduces the diversity and complexity of stock management, and therefore reduces vehicle costs.
[0013] The rear cross member according to the invention may include other characteristics which may be taken separately or in combination, and in particular:
[0014] - its lower wall may comprise two transversely spaced reinforcement stampings, suitable for being oriented so as to project downwards and allow the attachment of a fuel tank fixing part or an internal side member;
[0015] - in the presence of the first option, at least one of the stampings may comprise a through hole suitable for being passed through by a screw intended to ensure screwing of a fixing part of the fuel tank;
[0016] - also in the presence of the first option and possibly in combination with the last sub-option, at least one of the stampings may include a flat lower face suitable for allowing the welding of an internal spar.
[0017] The invention also proposes a land vehicle comprising a structure comprising, on the one hand, a rear floor located in front of a load floor, and, on the other hand, a rear cross member of the type presented above and fixedly secured to the rear floor and to the load floor.
[0018] The land vehicle according to the invention may include other characteristics which may be taken separately or in combination, and in particular:
[0019] - it may comprise a fuel tank fixedly secured to the lower wall of the rear cross member by at least one fixing part associated with a screw;
[0020] - in the presence of the first option, its fuel tank can be fixedly secured to the lower wall of the rear cross member by two fixing parts associated respectively with two screws;
[0021] - its structure may include two internal side members fixedly secured by welding to the lower wall of the rear cross member and to the rear floor;
[0022] - in the presence of the last option, it may include a battery capable of supplying electrical energy for an electric motor of a powertrain (or GMP) and fixedly secured by screwing to the internal side members;
[0023] - it can be of the automobile type. Brief description of the figures
[0024] Other characteristics and advantages of the invention will appear on examining the detailed description below, and the attached drawings (obtained in CAD / CAM (“Computer Aided Design / Computer Aided Drawing”)), in which:
[0025] [Fig. 1] schematically illustrates, in a bottom view, part of a first example of a land vehicle structure comprising a first example of embodiment of a rear cross member according to the invention adapted to a thermal GMP,
[0026] [Fig. 2] schematically illustrates, in a bottom view, the lower wall of the rear crossmember of Figure 1, before its integration into a thermal GMP vehicle structure,
[0027] [Fig. 3] schematically illustrates, in a bottom view, a part of a second example of a land vehicle structure comprising a second example of an embodiment of a rear cross member according to the invention adapted to a hybrid GMP,
[0028] [Fig. 4] schematically illustrates, in a bottom view, the lower wall of the rear crossmember of Figure 3, before its integration into a hybrid GMP vehicle structure,
[0029] [Fig. 5] schematically illustrates, in a bottom view, a part of a third example of a land vehicle structure comprising a third example of an embodiment of a rear cross member according to the invention adapted to an electric powertrain, and
[0030] [Fig. 6] schematically illustrates, in a bottom view, the lower wall of the rear crossmember of Figure 5, before its integration into an electric GMP vehicle structure. Detailed description of the invention
[0031] The invention aims in particular to propose a rear cross member (or cross member closure) TR intended to form part of a structure SV of a land vehicle V and adapted to the different engines that this vehicle V may have.
[0032] In the following, it is considered, by way of non-limiting example, that the land vehicle V is of the automobile type. This is for example a car. But the invention is not limited to this type of vehicle. It relates in fact to any land vehicle comprising a structure comprising a rear cross member (or cross member closure) serving as anchoring (or securing) zone for at least one element of the vehicle which depends on the latter's engine.
[0033] In Figures 1 to 6, the X direction is the longitudinal direction of the (land) vehicle V, which is substantially parallel to the lateral (or longitudinal) sides comprising the side doors, the Y direction is the transverse direction of the vehicle V, which is perpendicular to the longitudinal direction X, and the Z direction is the vertical direction of the vehicle V, which is perpendicular to the longitudinal X and transverse Y directions.
[0034] In the above and below, the concepts of "front" and "rear" are defined in relation to the front and rear ends of the vehicle V. Consequently, a front part of an element is intended to be oriented towards the front of the vehicle V, while a rear part of an element is intended to be oriented towards the rear of this same vehicle V.
[0035] Figures 1, 3 and 5 schematically illustrate three examples of embodiments of parts of a structure SV of a (land) vehicle V comprising a rear cross member (or cross member closure) TR according to the invention. This vehicle V has a structure which can be associated with different powertrains (or GMPs), namely a purely thermal GMP, a hybrid GMP (thermal and electric) and a purely electric GMP.
[0036] Note that vehicle V partially illustrated in Figure 1 has a purely thermal GMP, vehicle V partially illustrated in Figure 3 has a hybrid GMP and a dynamic rear axle, and vehicle V partially illustrated in Figure 5 has a purely electric GMP.
[0037] As illustrated in Figures 1, 3 and 5, the structure SV of a vehicle V according to the invention comprises in particular a rear cross member (or cross member closure) TR, a rear floor PR and a load floor PC.
[0038] The rear floor PR generally supports the rear bench seat of the vehicle V, is fixedly secured to the rear crossmember TR, and extends towards the rear a heel board (not shown) which is a structural element extending towards the rear a front floor (not shown). It is recalled that the heel board comprises a rear transverse part defining a crossmember (and therefore extending in the transverse direction Y), and against which the heels of the rear passengers of the vehicle V can rest.
[0039] The PC load floor is located behind the PR rear floor, fixedly attached to the TR rear cross member, and partly delimits the rear trunk of the vehicle V.
[0040] The rear cross member TR is suitable for being fixedly secured to two external side members, right and left (not shown) and to the lower faces of the front part of the load floor PC and the rear part of the rear floor PR. It comprises a main part (not visible in the figures), for example having a generally inverted U-shaped section, and a lower wall PI fixedly secured by welding to the main part, closing the cavity delimited by the latter, and intended to be oriented towards the ground once installed in the vehicle V.
[0041] This lower wall PI is arranged in such a way as to allow the attachment of either at least one fixing part PF of a fuel tank RC of the land vehicle V (figures 1 to 4, case of thermal and hybrid GMPs), or of two internal side members Ll of the structure SV (figures 5 and 6, case of the electric GMP).
[0042] As illustrated in Figures 1 and 3, each PF fixing part can, for example, pass under a part of the RC fuel tank associated with a thermal or hybrid GMP, and comprise ends secured by screwing to the lower wall PI and to the RC fuel tank or to another element of the SV structure (for example the heel board).
[0043] As partially illustrated in Figure 5, the two internal side members L1 are fixedly secured to the rear cross member TR and to the heel board between the two external side members. They are also fixedly secured to the underside of the rear floor PR. For example, these two internal side members L1 can be used to reinforce the structure SV and allow the fixed fastening by screwing of a rear part of a battery suitable for supplying electrical energy for an electric motor of an electric powertrain of the vehicle V.
[0044] Thanks to this unique, special arrangement of the PI lower wall, it is no longer necessary to use three different stamping tools to produce three different rear crossmember lower walls and different hardware sub-assemblies. From now on, a single stamping tool is sufficient, which significantly reduces diversity and inventory management, and therefore lowers vehicle costs.
[0045] For example, and as illustrated non-limitingly in Figures 1 to 6, the lower wall PI may comprise two reinforcement stampings ER which are spaced transversely, and capable of being oriented so as to project downwards. In this case, each reinforcement stamping ER, which constitutes a concave zone, is capable of allowing the securing of a fixing part PF (Figures 1 to 4) of a fuel tank RC or of an internal spar L1 (Figures 5 and 6).
[0046] Also for example, and as illustrated non-limitingly in Figures 1 to 4, when the powertrain of the vehicle V is thermal or hybrid, at least one of the reinforcement stampings ER may comprise a through hole TT which is suitable for being crossed by a screw intended to ensure the screwing of a fixing part PF of the fuel tank RC. Thus, in the first example of Figures 1 and 2 (thermal powertrain, but it could also be a hybrid powertrain associated with a multi-link type rear axle), only one of the two reinforcement stampings ER comprises a through hole TT because the fuel tank RC is held under the rear wall PR by a single fixing part PF screwed onto the lower wall PI via the single hole through TT. In the second example of figures 3 and 4 (hybrid and dynamic rear axle powertrain), each of the two reinforcement stampings ER includes a through hole TT because the fuel tank RC is held under the rear wall PR by two fixing parts PF screwed onto the lower wall PI via the two through holes TT.
[0047] It will be understood that each TT through hole is now made when necessary, and therefore to accommodate a screw, which advantageously avoids having to plug holes when they are not in use to ensure the sealing of a TR rear cross member. This saves time, reduces the diversity and complexity of stock management, and therefore reduces vehicle costs.
[0048] Also for example, and as illustrated non-limitingly and at least partially in figures 1 to 6, at least one of the reinforcement stampings ER may comprise a flat lower face suitable for allowing the joining by welding of an internal spar L1.
[0049] Thus, in the third example illustrated non-limitingly in figures 5 and 6, when the GMP of the vehicle V is electric, the two reinforcement stampings ER comprise a flat lower face suitable for allowing the welding of an internal side member L1. In this case, there is no through hole TT to be made in a reinforcement stamping ER.
[0050] It should be noted that in the first example in figures 1 and 2 (thermal powertrain, but it could also be a hybrid powertrain associated with a multi-link type rear axle), the two ER reinforcement stampings also have a flat lower face and only the lower face of one of them (ER) includes a TT through hole.
[0051] It will also be noted that in the second example of figures 3 and 4 (hybrid GMP associated with a dynamic rear axle), the two reinforcement stampings ER also have a flat lower face, and the two lower faces each include a through hole TT.
[0052] The invention makes it possible to reduce assembly time, production costs, logistics, and the number of additional parts or elements required for couplings.
Claims
CLAIMS
1. Rear cross member (TR) suitable for forming part of a structure (SV) of a land vehicle (V), said structure (SV) comprising a rear floor (PR) located in front of a load floor (PC), and said rear cross member (TR) being suitable for being fixedly secured to said rear floor (PR) and load floor (PC), characterized in that it comprises a lower wall (PI) arranged so as to allow the securing either of at least one fixing part (PF) of a fuel tank (RC) of said land vehicle (V), or of two internal side members (Ll) of said structure (SV).
2. Rear cross member according to claim 1, characterized in that said lower wall (PI) comprises two transversely spaced reinforcement stampings (ER), and suitable for being oriented so as to project downwards and to allow the attachment of a fixing part (PF) of said fuel tank (RC) or of an internal side member (Ll).
3. Rear cross member according to claim 2, characterized in that at least one of said reinforcement stampings (ER) comprises a through hole (TT) suitable for being passed through by a screw intended to ensure screw connection of a fixing part (PF) of said fuel tank (RC).
4. Rear cross member according to claim 2 or 3, characterized in that at least one of said reinforcement stampings (ER) comprises a flat lower face suitable for allowing the welding of an internal side member (L1).
5. Land vehicle (V) comprising a structure (SV) comprising a rear floor (PR) located in front of a load floor (PC), characterized in that it comprises a rear cross member (TR) according to one of the preceding claims, fixedly secured to said rear floor (PR) and load floor (PC).
6. Land vehicle according to claim 5, characterized in that it comprises a fuel tank (RC) fixedly secured to said lower wall (PI) of the rear cross member (TR) by at least one fixing part (PF) associated with a screw.
7. Land vehicle according to claim 6, characterized in that said fuel tank (RC) is fixedly secured to said lower wall (PI) of the rear cross member (TR) by two fixing pieces (PF) associated respectively with two screws.
8. Land vehicle according to claim 5, characterized in that said structure (SV) comprises two internal side members (Ll) fixedly secured by welding to said lower wall (PI) of the rear cross member (TR) and to said rear floor (PR).
9. Land vehicle according to claim 8, characterized in that it comprises a battery capable of supplying electrical energy for an electric motor of a powertrain and fixedly secured by screwing to said internal side members (L1).
10. Land vehicle according to one of claims 5 to 9, characterized in that it is of the automobile type.