REINFORCEMENT LONGEND FOR A MOTOR VEHICLE

Abstract

A longitudinal member (LV) is installed parallel to a longitudinal side (CL) of a floor (PV) of a motor vehicle's underbody (SV), and comprises a longitudinal main wall (PP) to which a reinforcement device (DR) is attached. This device includes: - lower (EI) and upper (ES) assemblies of first (C1) and second (C2) partitions, respectively, installed perpendicular to the main wall (PP), these first (C1) or second (C2) partitions having a step (DC) on a side facing the main wall (PP); - lower (EQI) and upper (EQS) longitudinal brackets to which the lower (EI) and upper (ES) assemblies are fixedly attached, and which are fixedly attached to the main wall (PP); and - a longitudinal stiffener (RL) comprising a first wall (PR1) housed within the steps (DC) and extended by a second wall (PR2) fixedly attached to the lower (EQI) or upper bracket. (EQS). Figure 2

Description

Title of the invention: REINFORCING SIDE LINER FOR A MOTOR VEHICLE Technical field of the invention

[0001] The invention relates to motor vehicles comprising a subframe having a floor having two opposite longitudinal sides, and more specifically the side members which frame these two opposite longitudinal sides. State of the art

[0002] Some motor vehicles include a subframe forming part of their structure and comprising a floor having right and left longitudinal sides and two side rails, right and left, installed respectively parallel to these right and left longitudinal sides.

[0003] In order to protect the passengers of the vehicles (automobiles) described above when the latter are subjected to a side impact on one of their right and left longitudinal sides, their side members may be equipped with a reinforcement device. Hereinafter, "side impact" means an impact along a direction having a non-zero transverse component.

[0004] This reinforcement device is designed to at least partially absorb the energy of the lateral impact and may, for this purpose, comprise, on the one hand, lower and upper assemblies of first and second bulkheads respectively, installed perpendicular to the main (substantially vertical) wall of its longeron, and, on the other hand, lower and upper longitudinal brackets to which the lower and upper assemblies are fixedly attached (for example, by welding) respectively, and fixedly attached (for example, by welding) to the main wall of the longeron. It should be noted that the first and second bulkheads may be arranged in a crenellated pattern.

[0005] The reinforcement devices described above improve the situation, but they do not provide complete satisfaction because the connection between the first and second partitions and the lower and upper brackets is weak, and therefore energy absorption may prove insufficient. Consequently, in the event of a lateral impact on a longitudinal member, the latter may be significantly deformed, which can cause damage to the floor and therefore also to equipment installed at least partially on it, which is potentially dangerous for the vehicle's passengers.

[0006] It should be noted that when the vehicle has a powertrain (or PWM) of the all-electric or hybrid (thermal and electric) type, it includes a rechargeable battery pack (or "pack") which can be installed between its side members, under its floor, and must also be protected in the event of a side impact. However, in the event of significant deformation of a side member, the rechargeable battery assembly can be damaged, which can cause a leak and / or a fire.

[0007] The invention therefore aims in particular to improve the situation in order to increase the passive protection of passengers, as well as of a possible rechargeable battery assembly, in the event of a side impact. Presentation of the invention

[0008] It proposes in particular for this purpose a longitudinal member, on the one hand, suitable for installation parallel to a longitudinal side of a floor of a motor vehicle underbody, and, on the other hand, comprising a main longitudinal wall to which is attached a reinforcement device comprising:

[0009] - lower and upper sets of first and second respectively partitions installed perpendicular to the main wall, and

[0010] - lower and upper longitudinal brackets, to which are fixed fixedly and respectively the lower and upper assemblies, and fixedly attached to the main wall.

[0011] This longeron is characterized by the fact that:

[0012] - that the first or second partitions include a step on one side oriented towards the main wall, and

[0013] - that its reinforcement device further comprises a longitudinal stiffener and comprising a first wall housed in the recesses and extended by a second wall fixedly attached to the lower or upper bracket.

[0014] Thanks to this stiffener, the first and second partitions have a much better connection with the lower and upper brackets, which allows them to perform their function of damping the energy of a lateral impact suffered by their vehicle.

[0015] The longeron according to the invention may include other features which may be taken separately or in combination, and in particular:

[0016] - the offsets can be defined in the vicinity of an interface between the first and second partitions;

[0017] - in the presence of the first option, the first wall of the stiffener can be so fixed lidarized to the first and second partitions at the level of the offsets;

[0018] - the offsets can be defined in the first partitions on the side which is oriented towards the main wall, and the second wall can be fixedly attached to the lower bracket;

[0019] - the stiffener may have a section, in a plane perpendicular to the wall main, in the general shape of an L;

[0020] - the first partitions can be arranged in crenellations, and the second partitions can also be arranged in crenellations;

[0021] - the second partitions can be supported by the first partitions;

[0022] - it may include a longitudinal lower wall, extending substantially to 90° to the main wall, and on which the lower assembly is fixedly installed.

[0023] The invention also proposes a motor vehicle comprising a base including a floor having right and left longitudinal sides and two side members, right and left, of the type presented above and installed respectively parallel to the right and left longitudinal sides.

[0024] For example, this motor vehicle may also include a rechargeable battery pack installed under the floor between the right and left side members. Brief description of the figures

[0025] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings (obtained using CAD / CAM (“Computer-Aided Design / Computer-Aided Manufacturing”)), in which:

[0026] [Fig. 1] schematically illustrates, in a side perspective view, part of an example of a motor vehicle underbody comprising an example of an embodiment of a side member according to the invention,

[0027] [Fig.2] schematically illustrates, in a cross-sectional view in a transverse and vertical plane at the level of the right longitudinal member, a right-hand part of the subframe of [Fig.1], and

[0028] [Fig.3] schematically illustrates, in a side perspective view, part of the reinforcement device of the right spar of figures 1 and 2. Detailed description of the invention

[0029] The invention aims in particular to provide a longitudinal LV intended to be part of a subframe SV of a motor vehicle and comprising a reinforcement device DR with a high capacity for damping the energy of a lateral impact.

[0030] In what follows, the motor vehicle is considered, by way of non-limiting example, to be a car. However, the invention is not limited to this type of motor vehicle. It relates in fact to any motor vehicle comprising a structure including a floor (incorporating optional crossmember(s)) framed by two longitudinal members.

[0031] In figures 1 to 3 the direction X is intended to be parallel to the longitudinal direction of the vehicle (automobile), which is substantially parallel to the lateral (or longitudinal) sides comprising the side doors, the direction Y is intended to be parallel to the transverse direction of the vehicle, which is perpendicular to the longitudinal direction X, and the direction Z is intended to be parallel to the vertical direction of the vehicle, which is perpendicular to the longitudinal direction X and the transverse direction Y.

[0032] Figures 1 and 2 schematically illustrate part of an example of a vehicle (automobile) underbody SV, including an example of an embodiment of a longitudinal member LV according to the invention. Although it is only partially shown in Figures 1 and 2 (only for the right side), the underbody SV includes, in particular, a floor PV having right and left longitudinal sides CL, and two longitudinal members LV, right and left, installed respectively parallel to the right and left longitudinal sides CL.

[0033] It should be noted that in the example illustrated, but not limited to, in [Fig. 2], the vehicle also includes a rechargeable battery pack EB installed under the floor PV between the right and left side members LV. However, this is not mandatory, as the invention also applies when the vehicle does not have a rechargeable battery pack EB.

[0034] The rechargeable battery assembly EB comprises a battery tray BB housing a rechargeable battery BR (preferably with its control electronics), and fixedly attached (by screws) to the PV floor (for example, at a peripheral groove in the latter (PV)). It should be noted that in the example illustrated, but not limited to, in [Fig. 2], the PV floor acts as a protective cover for the battery tray BB, the rechargeable battery BR, and any control electronics. However, the rechargeable battery assembly EB could include a dedicated protective cover.

[0035] For example, the rechargeable BR battery may include at least one cell module comprising at least two electrical energy storage cells. Here, "electrical energy storage cell" means a rechargeable and possibly electrochemical cell (for example, of the lithium-ion (or Li-ion) or Ni-Mh or Ni-Cd type).

[0036] As illustrated at least partially in Figures 1 to 3, a longitudinal member LV, according to the invention, comprises at least one main longitudinal wall PP (i.e. extending along the longitudinal direction X) to which a reinforcement device DR is attached. Here, the main wall PP is mainly installed in a substantially longitudinal and vertical plane XZ.

[0037] This reinforcement device DR comprises a lower set El of first partitions Cl, an upper set ES of second partitions C2, a lower bracket EQI, an upper bracket EQS, and a stiffener RL.

[0038] The first partitions Cl of the lower assembly El are installed perpendicular to the main wall PP. The second partitions Cl of the upper assembly ES are also installed perpendicular to the main wall PP. As illustrated in Figures 1 to 3, the first Cl or second C2 partitions include a step DC on one side that is oriented towards the main wall PP. For example, Each DC offset can be obtained by a cut made in the thickness of a first partition Cl, over a chosen length (here along the transverse direction Y).

[0039] The lower bracket EQI is longitudinal (meaning that it extends along the longitudinal direction X, preferably over a large part of the longitudinal extent of the main wall PP of the longeron LV). It has, for example, a cross-section (here in a YZ plane) in the general shape of an L. Furthermore, the lower bracket EQI is fixedly attached to the main wall PP, for example by welding (but it could also be by screwing or riveting).

[0040] The upper bracket EQS is also longitudinal (meaning that it extends along the longitudinal direction X, preferably over a large part of the longitudinal extent of the main wall PP of the longeron LV). It has, for example, a cross-section (here in a YZ plane) in the general shape of an inverted L. Furthermore, the upper bracket EQS is fixedly attached to the main wall PP, for example by welding (but it could also be by screwing or riveting).

[0041] The lower assembly El is fixedly attached to the lower bracket EQI, for example by welding (but it could also be by screwing or riveting). The upper assembly ES is fixedly attached to the upper bracket EQS, for example by welding (but it could also be by screwing or riveting).

[0042] The stiffener RL is longitudinal (meaning that it extends along the longitudinal direction X, preferably at least over almost the entire longitudinal extent of the lower bracket EQI and upper bracket EQS). Furthermore, this stiffener RL comprises a first wall PR1 which is housed in the recesses DC, and which is extended by a second wall PR2 fixedly attached to the lower bracket EQI or the upper bracket EQS.

[0043] The height (along the vertical direction Z) of each step DC is therefore slightly greater than the thickness (along the vertical direction Z) of the first wall PRL

[0044] Thanks to this stiffener RL, which penetrates the first Cl and second C2 partitions while being fixedly attached to the lower bracket EQI or the upper bracket EQS, the first Cl and second C2 partitions of the lower El and upper ES assemblies have a much better connection with the lower EQI and upper EQS brackets. This allows the first Cl and second C2 partitions to perform their function of absorbing the energy of a lateral impact sustained by the vehicle. The passive protection of the passengers, as well as of the possible rechargeable battery pack EB, is therefore increased in the event of a lateral impact.

[0045] For example, the first partitions Cl, the second partitions C2, the lower bracket EQI, the upper bracket EQS, and the stiffener RL can be made in steel or aluminium.

[0046] Also, for example, and as illustrated, but not limited to, in Figures 1 to 3, the DC offsets can be defined in the vicinity of the interface between the first Cl and second C2 partitions. This optimizes the connection between the first Cl and second C2 partitions and the lower EQI and upper EQS brackets, thus promoting the damping of lateral impact energy by the first Cl and second C2 partitions. However, the DC offsets could be defined at a different vertical level than the aforementioned interface.

[0047] It should be noted that, with the previous option, it is advantageous for the first wall PR1 of the stiffener RL to be fixedly attached to the first Cl and second C2 partitions at the DC offsets, for example by welding (but it could also be by screwing or riveting). This ensures that all the first Cl and second C2 partitions are connected to each other in addition to being connected to the lower bracket EQI and upper bracket EQS.

[0048] Also, for example, and as illustrated, but not limited to, in Figures 1 to 3, the DC offsets can be defined in the first partitions Cl on the side facing the main wall PP, and the second partition PR2 can be fixedly attached to the lower bracket EQI. But in a first embodiment not shown, the DC offsets could be defined in the first partitions Cl on the side facing the main wall PP, and the second partition PR2 could be fixedly attached to the upper bracket EQS. In a second embodiment not shown, the DC offsets could be defined in the second partitions C2 on the side facing the main wall PP, and the second partition PR2 could be fixedly attached to the upper bracket EQS.

[0049] Also, for example, and as illustrated, but not limited to, in Figures 2 and 3, the stiffener RL may have a cross-section, in a plane (here YZ) perpendicular to the main wall PP, in the general shape of an L (possibly inverted). This type of cross-section offers very good resistance in the event of a lateral impact.

[0050] Also, for example, and as illustrated but not limited to Figures 1 and 3, the first partitions Cl can be arranged in crenellations, and the second partitions C2 can also be arranged in crenellations. But other arrangements can be considered, and in particular in accordion or triangular configurations, for example.

[0051] Also, for example, and as illustrated non-limitingly in Figures 1 to 3, the second partitions C2 can be supported by the first partitions CL. This is particularly interesting when the first Cl and second C2 partitions are arranged in crenellations, because the superimposed bearing surfaces are large and allow the energy damping capacity to increase while facilitating welding.

[0052] Also, for example, and as illustrated without limitation in Figures 1 and 2, the LV spar may include a longitudinal lower wall PI (meaning that it extends along the longitudinal direction X), extending substantially at 90° from the main wall PP, and on which the lower assembly El is fixedly installed. The word "substantially" here means equal to 90° plus or minus five degrees. This not only supports the reinforcement device DR, but also allows the substantially horizontal portion of the lower bracket EQI to be fixedly attached to this lower wall PI, for example by welding (but it could also be by screwing or riveting), and thus further reinforces the anchoring of the reinforcement device DR to allow the first Cl and second C2 bulkheads to absorb the energy effectively.

Claims

Demands

1. Longitudinal member (LV) suitable for installation parallel to a longitudinal side (CL) of a floor (PV) of a subframe (SV) of a motor vehicle, said longitudinal member (LV) comprising a longitudinal main wall (PP) to which is attached a reinforcement device (DR) comprising i) lower (El) and upper (ES) assemblies respectively of first (Cl) and second (C2) partitions installed perpendicular to said main wall (PP), and ii) lower (EQI) and upper (EQS) longitudinal brackets, to which are fixedly attached said lower (El) and upper (ES) assemblies respectively, and fixedly attached to said main wall (PP), characterized in that said first (Cl) or second (C2) partitions comprise a step (DC) on a side oriented towards said main wall (PP),and in that said reinforcement device (DR) further comprises a longitudinal stiffener (RL) having a first wall (PR1) housed in said recesses (DC) and extended by a second wall (PR2) fixedly attached to said lower (EQI) or upper (EQS) bracket.

2. Longeron according to claim 1, characterized in that said step-ins (DC) are defined in the vicinity of an interface between said first (Cl) and second (C2) partitions.

3. Longeron according to claim 2, characterized in that said first wall (PR1) of the stiffener (RL) is fixedly attached to said first (Cl) and second (C2) partitions at said offsets (DC).

4. Stringer according to any one of claims 1 to 3, characterized in that said offsets (DC) are defined in said first partitions (Cl) on said side oriented towards said main wall (PP), and said second wall (PR2) is fixedly attached to said lower bracket (EQI).

5. Longeron according to any one of claims 1 to 4, characterized in that said stiffener (RL) has a section, in a plane perpendicular to said main wall (PP), in the general shape of L.

6. Longeron according to any one of claims 1 to 5, characterized in that said first partitions (Cl) are arranged in crenellations, and said second partitions (C2) are arranged in crenellations.

7. Longeron according to any one of claims 1 to 6, characterized in that said second partitions (C2) are supported by said first partitions (Cl).

8. Longeron according to any one of claims 1 to 7, characterized in that it comprises a longitudinal lower wall (PI), extending substantially at 90° from said main wall (PP), and on which said lower assembly (El) is fixedly installed.

9. Motor vehicle comprising a subframe (SV) having a floor (PV) having right and left longitudinal sides (CL), characterized in that said subframe (SV) further comprises two longitudinal members (LV), right and left, according to any one of the preceding claims, installed respectively parallel to said right and left longitudinal sides (CL).

10. Vehicle according to claim 9, characterized in that it comprises a rechargeable battery assembly (EB) installed under said floor (PV) between said right and left longitudinal members (LV).

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