REINFORCEMENT DEVICE FOR A MOTOR VEHICLE UNDERFLOOR WITH A BATTERY TRAY

Abstract

A reinforcement device (RD) is fitted to a motor vehicle comprising a front section (BS) followed by an underbody (UB) under which a battery tray (BB) is fixedly installed. The battery tray has a front section (PVB) and, on one hand, extends along the longitudinal direction of the vehicle, being fixedly attached to the underbody (BS), and, on the other hand, is fixedly attached to the front section (BS) and supports a fixed front mounting bracket (PFV) of the battery tray (BB). The purpose of this device is to distribute the forces absorbed by the front section (BS) during a frontal impact to the underbody (BS). Figure 1

Description

Title of the invention: REINFORCEMENT DEVICE FOR A MOTOR VEHICLE UNDERFLOOR WITH A BATTERY TRAY Technical field of the invention

[0001] The invention relates to motor vehicles having a battery tray installed under the underbody, and more specifically to the reinforcement of the underbody to protect the battery tray during a frontal impact on this type of vehicle. Prior art

[0002] Some motor vehicles include a front block which is followed by a subframe under which a battery tray housing a rechargeable battery is fixedly installed.

[0003] The front block generally includes at least one front cradle (with its right and left extensions), right and left crossmembers and right and left upper arms which together ensure, in particular, the support of at least part of the powertrain (or PWM), hybrid or all-electric, of the vehicle, as well as cradle support closure pieces, right and left.

[0004] The subframe generally comprises, in particular, a front floor, a central floor, seat cross members, right and left underfloor stretchers, and optionally front and central tunnels installed in a longitudinal, mid-position. The front floor is fixedly attached to the cradle support closure pieces and to the underfloor stretchers. The front tunnel is fixedly attached to the underside of the front floor, extending longitudinally at least to the front of the battery tray. The battery tray is fixedly attached, in particular, to the underfloor stretchers.

[0005] When the vehicle is subjected to a frontal impact, possibly with a small overlap, the front end is compressed, and its subframe support closure components are therefore subjected to potentially significant stresses. This can then cause deformation of the front floor and / or the front tunnel, and this deformation can in turn damage the battery tray and possibly part of the rechargeable battery and / or the electronic components controlling it, which can render the rechargeable battery unusable (and possibly the vehicle if its powertrain is all-electric) and / or cause a leak or a fire, potentially dangerous for the vehicle and its passengers and for the environment.

[0006] To reduce the potential for deformation of the front floor and / or front tunnel, and thus limit the risk of damage to the battery tray, it would be possible to increase the thickness of the sheet metal used to make the front floor and front tunnel, and to permanently attach the front part of the battery tray to the front floor and / or front tunnel. However, this would increase the vehicle's mass and therefore its cost and power consumption.

[0007] The invention therefore aims in particular to improve the situation. Presentation of the invention

[0008] In particular, it proposes for this purpose a reinforcement device suitable for equipping a motor vehicle comprising a front block followed by a base under which a battery tray comprising a front part is fixedly installed.

[0009] This reinforcement device is characterized by the fact that it is designed to extend along a longitudinal direction of the vehicle by being fixedly attached to the underbody, and to be fixedly attached to the front block and to fixedly support a front fixing bracket of the battery tray, in order to distribute into the underbody the forces absorbed by the front block during a front impact suffered by the vehicle.

[0010] Thanks to the invention, the underbody is reinforced so as to significantly limit, or even prevent, the deformation of at least its front floor, and thus to significantly limit, or even prevent, damage to the battery tray (and its contents), which strengthens the safety of the vehicle and its passengers and helps to avoid polluting the environment.

[0011] The reinforcement device according to the invention may include other features which may be taken separately or in combination, and in particular:

[0012] - in the presence of a front block comprising support closure parts cradle, right and left, installed along a transverse direction of the vehicle and a subframe comprising a front floor fixedly attached to the cradle support closing pieces and under which the battery tray is installed, it may comprise, on the one hand, a first part capable of extending along the longitudinal direction having front and rear extremities placed opposite respectively an associated cradle support closing piece and the front part of the battery tray, and being fixedly attached to the front floor, the rear extremity being intended to fixedly support the associated front fixing bracket, and, on the other hand, a second part fixedly attached to this front extremity and capable of being fixedly attached to the associated cradle support closing piece,in order to distribute at least part of the forces absorbed by this associated cradle support closure piece into the front floor;

[0013] - in the presence of the first option, and in the presence of a base comprising in a longitudinal median position a front tunnel fixedly attached to an underside of the front floor extending at least to the front part of the battery tray, the first part may be suitable for extending along the front tunnel and in the vicinity of the latter, in order to define a reinforcement of the front tunnel and to distribute into the latter a part of the forces received by the associated cradle support closure piece;

[0014] - also in the presence of the first option, the first part can be hollow and may present a section in a transverse and vertical plane in the general shape of a U;

[0015] - also in the presence of the first option, the second part can be hollow and may present a section in a longitudinal and vertical plane in the general shape of a right triangle;

[0016] - also in the presence of the first option, the second part can be joined fixed to the first part by welding and / or screwing, or alternatively the first and second parts can be part of a single piece;

[0017] - also in the presence of the first option, the first part may include at least two first lateral wings, right and left, suitable for being fixedly attached to the front floor;

[0018] - also in the presence of the first option, the second part may include a transverse front wing designed to be fixedly attached to the associated cradle support closure piece and two second lateral wings, right and left, designed to be fixedly attached to the front floor;

[0019] - also in the presence of the first option, each of the first and second parts can be made of steel;

[0020] - also in the presence of the first option, each of the first and second parts may have a thickness greater than or equal to 1 mm;

[0021] - it may exhibit an elastic limit which is greater than or equal to 300 MPa.

[0022] The invention also proposes a motor vehicle comprising, on the one hand, a front block followed by a subframe under which is fixedly installed a battery tray having a front part equipped with two front fixing tabs, right and left, and, on the other hand, two reinforcement devices of the type presented above, right and left, and fixedly attached to the front block and subframe and to which are fixedly attached respectively front fixing tabs, right and left, of the battery tray. Brief description of the figures

[0023] 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:

[0024] [Fig-1] schematically illustrates, in a perspective view from below, some parts of examples of a battery tray, underbody and front block of a motor vehicle to which are joined two examples of an embodiment of a reinforcement device according to the invention,

[0025] [Fig.2] schematically illustrates, in a perspective view from below, the coupling between the right reinforcement device, battery tray, underbody and front block of the [Fig.l],

[0026] [Fig.3] schematically illustrates, in a perspective view from below, the right reinforcement device of the [Fig. 1], before its installation in a vehicle, and

[0027] [Fig.4] schematically illustrates, in a perspective view from below, the first part of the right reinforcement device of [Fig.3], before the second part of this same reinforcement device is fixedly attached to it. Detailed description of the invention

[0028] The invention aims in particular to provide a reinforcement device DR intended to be part of a subframe SV of a motor vehicle with a battery tray BB installed under the subframe SV, and allowing the subframe SV to be reinforced to protect the battery tray BB when the motor vehicle suffers a front impact.

[0029] In what follows, it is considered, by way of non-limiting example, that each DR reinforcement device is intended to be part of a motor vehicle of the car type. However, the invention is not limited to this type of motor vehicle. It relates in fact to any motor vehicle comprising a front section followed by a subframe under which a battery tray is fixedly installed.

[0030] In figures 1 to 4, 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.

[0031] In the foregoing and following, the term "front" is defined with respect to the front end of the vehicle, and the term "rear" is defined with respect to the rear end of the vehicle (opposite the front end). Therefore, the front part of an element is (intended to be) oriented towards the front end of the vehicle. while the rear part of this element is (intended to be) oriented towards the rear end of the vehicle.

[0032] Figure 1 schematically illustrates part of an example of the structure of a vehicle (automobile) comprising a front block BV and a subframe SV, under which a battery tray BB is installed and comprising two reinforcement devices DR, right and left, according to the invention.

[0033] Although this is very partially illustrated in [Fig.1], the front block includes, in particular, on the one hand, a front cradle (with its right and left extensions), right and left crossmembers and right and left upper arms which together ensure, in particular, the support of at least part of the powertrain (or PWM), hybrid or all-electric, of the vehicle, and, on the other hand, cradle support closure pieces PFSB, right and left, which extend along the transverse direction Y.

[0034] Also, although this is only partially illustrated in Figures 1 and 2, the SV underframe generally comprises, in particular, a front floor PVS, a central floor, seat cross members, underfloor frame members BSP (right and left), and optionally a front tunnel TNV and a central tunnel installed in a longitudinal, mid-position, one after the other to complement each other. The front floor PVS is specifically fixedly attached to the cradle support end pieces PFSB and to the underfloor frame members (or longitudinal members) BSP. The front tunnel TNV is fixedly attached to the underside FI of the front floor PVS, extending longitudinally at least as far as the front part PVB of the battery tray BB.

[0035] Although not shown in the figures, the BB battery tray houses a rechargeable battery and generally a battery box comprising an interface device, voltage / current measurement means, and a battery computer. For example, the BB battery tray, the rechargeable battery, and the battery box may form part of a battery assembly (or "pack"). Note that the central floor and possibly part of the PVS front floor may define a protective cover (or lid) for the battery assembly. Otherwise, the battery assembly includes its own dedicated protective cover (or lid).

[0036] It should also be noted that the rechargeable battery is used to supply electrical energy to at least one electric drive machine of the vehicle's powertrain.

[0037] As illustrated in Figures 1 to 3, each reinforcement device DR, according to the invention, is adapted to extend along the longitudinal direction X of the vehicle by being fixedly attached to the underbody SV. Furthermore, each reinforcement device DR, according to the invention, is adapted to be fixedly attached to the front block BV and to fixedly support a front mounting bracket PFV of the battery tray BB, in order to distribute in the SV subframe forces which are absorbed by the front BV block when the vehicle suffers a front impact, possibly with a small overlap.

[0038] Thus, when the vehicle sustains a frontal impact and its subframe support closure components PFSB are subjected to (potentially significant) stresses, its two reinforcement devices DR strengthen the underbody SV to protect the battery tray BB (and its contents). This significantly limits, or even prevents, deformation of the front floor PVS and / or the possible front tunnel TNV, and consequently significantly limits, or even prevents, damage to the battery tray BB and potentially some of its contents. As a result, the probability of the rechargeable battery becoming unusable (and possibly also the vehicle when its powertrain is all-electric) and / or of a leak or fire occurring is very low, or even zero, which enhances the safety of the vehicle and its passengers and prevents environmental pollution.Furthermore, this avoids increasing the thickness of the sheet metal used to make the PVS front floor and the possible TNV front tunnel, and therefore avoids significantly increasing the vehicle's mass, cost, and power consumption.

[0039] It should be noted, as illustrated (though not exhaustively) in Figures 1 and 2, that the underbody SV generally also includes front cross members TV, right and left, each installed under the front floor PVS, extending along the transverse direction Y between the front tunnel TNV and one of the two underfloor beams (or longitudinal members) BSP (being fixedly attached to the latter (BSP)), and to which the front part PVB of the battery tray BB is fixedly attached. In this case, the two front mounting brackets PFV pass respectively in front of the central ends of these front cross members TV so that they can be fixedly attached to the rear ends ER of the two reinforcement devices DR. This latter fixed attachment can be achieved, for example, by screwing. But it could also be achieved by welding.Such an arrangement makes it possible to limit the forces along the vertical Z direction which are absorbed by the front fixing brackets PFV due to their fixed attachment to the reinforcement devices DR. .

[0040] For example, and as illustrated non-limitingly in Figures 1 to 3, each reinforcement device DR may comprise first PI and second P2 parts.

[0041] The first part PI is adapted to extend along the longitudinal direction X, having a front end EV positioned opposite the associated cradle support closure piece PFSB, and a rear end ER opposite the front end EV and positioned opposite the front part PVB of the battery tray BB. Furthermore, the first part PI is at least fixedly attached to the front floor PVS (and more precisely to the inner face FI of the latter (PVS)). Moreover, the rear end ER of the The first part PI is intended to permanently support the associated front mounting bracket PFV of the front PVB part of the BB battery tray.

[0042] The second part P2 is designed to extend along the vertical direction Z, is fixedly attached to the front end EV of the first part PI and is designed to be fixedly attached to the associated cradle support closure piece PFSB.

[0043] This arrangement of the first PI and second P2 parts is designed to distribute at least a portion of the forces absorbed by the associated PFSB cradle support closure piece to the front floor PVS. This is because the second part P2 is fixedly attached to a PFSB cradle support closure piece and therefore receives a portion of the forces absorbed by the latter (PFSB), and the first part PI is fixedly attached to the front floor PVS and therefore advantageously transmits this portion of the received forces to the latter (PVS).

[0044] Also, for example, and as illustrated without limitation in Figures 1 and 2, when the underbody SV includes the front tunnel TNV, the first part PI of each reinforcement device DR can be adapted to extend along the front tunnel TNV (and more precisely along one of its longitudinal sides (right and left)) and in the vicinity of this front tunnel TNV. This allows each reinforcement device DR to define a reinforcement of the front tunnel TNV and to distribute into the latter (TNV) a portion of the forces that are absorbed by the associated cradle support closure piece PFSB.

[0045] It will be understood that this allows for a further distribution of the forces transferred to a DR reinforcement device by the associated PFSB cradle support closure piece, and thus further limits deformations of the PVS front floor and the TNV front tunnel, and consequently further limits damage to the BB battery tray (and its contents). This further reduces the probability of the rechargeable battery becoming unusable and / or of a leak or fire.

[0046] Also, for example, and as illustrated non-limitingly in Figures 3 and 4, the first part PI of each reinforcement device DR can be hollow and can have a cross-section in a transverse and vertical plane (here a YZ plane) in the general shape of a U. Such an arrangement advantageously allows each reinforcement device DR to deform in order to partially absorb the energy of the forces received.

[0047] Also, for example, and as illustrated, but not limited to, in [Fig. 3], the second part P2 of each reinforcement device DR can be hollow and can have a cross-section in a longitudinal and vertical plane (here, a plane XZ) generally in the shape of a right triangle. Such an arrangement advantageously allows the forces received by the first part PI of each reinforcement device DR to be transferred to the first part PI of the reinforcement device DR. second part P2 of the latter (DR), but also to the second part P2 to deform in order to partially absorb the energy of the forces received.

[0048] At least two embodiments can be envisaged for each DR reinforcement device.

[0049] In a first embodiment illustrated in Figures 1 to 4, each reinforcement device DR can be made by joining two parts, which respectively constitute its first PI and second P2 sections and are initially independent. In this case, the second part (or section) P2 can be permanently joined to the first part (or section) PI by welding and / or screwing.

[0050] It should be noted that in the first embodiment, the second part P2 of each reinforcement device DR can, as illustrated non-limitingly in [Fig. 3], comprise a wide longitudinal rear wing AR designed to be fixedly attached to the first part PI. This arrangement facilitates the transfer of forces from the second part P2 to the first part PI.

[0051] In a second embodiment (not illustrated), each reinforcement device DR can be a single piece. In this case, the first PI and second P2 parts are part of this single piece, and the second part P2 extends upwards from the first PI part at the front end EV.

[0052] In both embodiments the first PI and second P2 parts can optionally be produced by bending and / or stamping and / or cutting operations.

[0053] Also, for example, and as illustrated, without limitation and at least partially, in Figures 1 to 4, the first part PI of each reinforcement device DR may comprise at least two first side wings ALI, right and left, which are designed to be fixedly attached to the front floor PVS. This fixed attachment may be achieved, for example, by welding. However, it could also be achieved by screwing. It should be noted that in the example illustrated, without limitation and at least partially, in Figures 1 to 4, the first part PI of each reinforcement device DR comprises four first side wings ALI right and four first side wings ALI left. However, the number of first side wings ALI right and the number of first side wings ALI left may take any value greater than or equal to one.Generally speaking, the higher these numbers are, the better the distribution of forces received in the front floor PVS and the possible front tunnel TNV.

[0054] It should also be noted, as illustrated non-limitingly in [Fig. 4], that the first part PI of each reinforcement device DR may also include at least one first transverse front wing ATI suitable for being fixedly attached to the associated cradle support closure piece PFSB. This fixed attachment may This can be done, for example, by welding. But it could also be done by screwing. This arrangement facilitates the transfer of forces between the PFSB cradle support closure piece and the first part PI (and not only via the second part P2).

[0055] It should also be noted, as illustrated in Figures 2 and 3, that the second part P2 of each reinforcement device DR may include a transverse front wing AT2 designed to be fixedly attached to the associated cradle support closure piece PFSB, and two second lateral wings AL2, right and left, designed to be fixedly attached to the front floor PVS. These fixed attachments may be made, for example, by welding. But they could also be made by screwing. This arrangement requires, as illustrated, that each second part P2 almost completely covers the associated first part PI and, above all, has right and left extensions upwards (and therefore towards the front floor PVS) which respectively include the second right and left lateral wings AL2.Furthermore, this arrangement facilitates the transfer of forces between the cradle support closure piece PFSB and the second part P2 and the distribution of forces transmitted in the front floor PVS (and not only via the first part PD- .

[0056] It should also be noted, as illustrated (but not limited to) in Figures 2 and 3, that the second part P2 of each reinforcement device DR may also include a longitudinal front wing AV designed to be fixedly attached to the lower part of the associated cradle support closure piece PFSB. This fixed attachment can be achieved, for example, by welding. However, it could also be achieved by screwing. This arrangement further facilitates the transfer of forces between the cradle support closure piece PFSB and the second part P2.

[0057] Preferably, each DR reinforcement device has a yield strength greater than or equal to 300 MPa. This allows it to deform elastically as long as the stress it is subjected to is not very high.

[0058] It should also be noted that each of the first PI and second P2 parts can, for example, be made of steel. But other strong materials with a high yield strength (typically greater than 300 MPa) can be used.

[0059] It should also be noted that each of the first PI and second P2 parts can, for example, have a thickness greater than or equal to 1 mm. By way of example, this thickness can be between 1 mm and 2 mm.

Claims

Demands

1. Reinforcement device (RD) suitable for equipping a motor vehicle comprising a front block (BV) followed by a subframe (SV) under which is fixedly installed a battery tray (BB) having a front part (PVB), characterized in that it is suitable for extending along a longitudinal direction of said vehicle by being fixedly attached to said subframe (SV), and for being fixedly attached to said front block (BV) and for fixedly supporting a front fixing bracket (PFV) of said battery tray (BB), in order to distribute into said subframe (SV) forces absorbed by said front block (BV) during a front impact suffered by said vehicle.

2. Reinforcement device according to claim 1, characterized in that in the presence of a front block (BV) comprising right and left cradle support closure pieces (PFSB), installed in a transverse direction of said vehicle and of a subframe (SV) comprising a front floor (PVS) fixedly attached to said cradle support closure pieces (PFSB) and under which said battery tray (BB) is installed, it comprises i) a first part (PI) adapted to extend in said longitudinal direction having front (EV) and rear (ER) extremities placed opposite respectively an associated cradle support closure piece (PFSB) and said front part (PVB), and being fixedly attached to said front floor (PVS), said rear extremity (ER) being intended to fixedly support the associated front mounting bracket (PFV),and ii) a second part (P2) fixedly attached to said front end (EV) and suitable for being fixedly attached to said associated cradle support closure piece (PFSB), in order to distribute at least a portion of the forces absorbed by said associated cradle support closure piece (PFSB) into said front floor (PVS).

3. A reinforcement device according to claim 2, characterized in that, in the presence of a subframe (SV) comprising, in a median longitudinal position, a front tunnel (TNV) fixedly attached to an underside (FI) of said front floor (PVS) extending at least as far as said front portion (PVB), said first portion (PI) is adapted to extend along said front tunnel (TNV) and in the vicinity thereof, in order to define a reinforcement of said tunnel before (TNV) and to distribute in the latter (TNV) a part of the said forces received by the said cradle support closure piece (PFSB) associated.

4. Reinforcement device according to claim 2 or 3, characterized in that said first part (PI) is hollow and has a cross-section in a transverse and vertical plane in the general shape of U.

5. Reinforcement device according to any one of claims 2 to 4, characterized in that said second part (P2) is hollow and has a cross-section in a longitudinal and vertical plane in the general shape of a right triangle.

6. Reinforcement device according to any one of claims 2 to 5, characterized in that said second part (P2) is fixedly attached to said first part (PI) by welding and / or screwing.

7. Reinforcement device according to any one of claims 2 to 5, characterized in that said first (PI) and second (P2) parts are part of a single piece.

8. Reinforcement device according to any one of claims 2 to 7, characterized in that said first part (PI) comprises at least two first lateral wings (ALI), right and left, suitable for being fixedly attached to said front floor (PVS).

9. Reinforcement device according to any one of claims 2 to 8, characterized in that said second part (P2) comprises a transverse front wing (AT2) adapted to be fixedly attached to said associated cradle support closure piece (PFSB) and two second lateral wings (AL2), right and left, adapted to be fixedly attached to said front floor (PVS).

10. Motor vehicle comprising a front block (BV) followed by a subframe (SV) under which is fixedly installed a battery tray (BB) comprising a front part (PVB), characterized in that it further comprises two reinforcement devices (DR) according to one of the preceding claims, right and left, fixedly attached to said front block (BV) and subframe (SV) and to which are fixedly attached respectively front fixing brackets (PFV), right and left, of said battery tray (BB).

Images