MOTOR VEHICLE WITH TRACTION BATTERY SUPPORTS LOCATED IN FRONT OF THE REAR SIDES

Abstract

A motor vehicle comprising, on each side of the vehicle, a longitudinal member (12) located behind the passenger compartment floor, receiving beneath it a traction battery (2) of this vehicle, this longitudinal member (12) having successively, from the floor, after a first upward angle (22), an inclined intermediate portion (24), then after a second downward angle (26), a final portion (28), the vehicle comprising, below each intermediate portion of the longitudinal member (24), a rear support (30) which supports the rear end of the traction battery (2), each rear support (30) comprising a reinforcing side plate (42) which is fixed to one side of the rear longitudinal member (12). Figure 2

Description

Title of the invention: MOTOR VEHICLE WITH TRACTION BATTERY SUPPORTS POSITIONED IN FRONT OF THE REAR SIDE RIMS

[0001] The present invention relates to a motor vehicle comprising traction battery supports which are arranged in front of the rear side members, as well as a range of motor vehicles including this type of vehicle.

[0002] A known type of electric or hybrid motor vehicle, presented in particular by document FR-A1-3134782, includes a vehicle traction battery arranged flat under the passenger compartment floor, which is framed on each side by a lower body forming a lateral longitudinal member ensuring the rigidity of the vehicle body as well as protection of this battery against side impacts.

[0003] Each side member extends into a rear member comprising, successively after a first angle, an inclined intermediate section that rises, and then after a second angle, a substantially horizontal final rear section supporting the vehicle's trunk floor, which is at a higher level than the passenger compartment. The rear members form a raised and robust structure supporting the vehicle's rear axle below.

[0004] Motor vehicles are subjected to standardized crash tests to verify passenger safety, including a rear-end impact offset to one side of the vehicle that compresses a rear side member. Furthermore, during these crashes, it is necessary to limit deformation of the traction battery box located in front of the rear side members, in order to prevent, in particular, damage to the electrochemical cells inside, which could lead to a fire.

[0005] Generally, in the event of a significant rear impact on the vehicle, the final section of the longitudinal member can be displaced forward, causing the intermediate section to straighten and tilt more sharply, resulting in a more pronounced bend in the two successive angles. The straightening of the first angle can cause the floor located at that point to sink in, and deformation of a battery box fixed directly below it.

[0006] The vehicle according to the prior art has on the second corner of the rear longitudinal member a sheet metal reinforcement comprising a lower face fixed under the final rear part and the inclined intermediate part, and a lateral face fixed on the side of the longitudinal member, so as to reinforce the second corner in order to enable it to better resist rear impacts.

[0007] However, this specific reinforcement added to the side member requires the management of special parts, including their manufacture and their attachment to the vehicle body, which poses problems of additional operating time and higher costs.

[0008] Alternatively, it is known to increase the thickness of the rear longitudinal member sheets and the strength of the steel used, which results in a greater vehicle mass and higher costs, particularly with high-strength steels which are expensive.

[0009] However, in the case of a range of vehicles with traction batteries of varying lengths, some with a shorter rear end that is less likely to be damaged by this type of rear impact, significant standardization of body construction, incorporating the same longitudinal members (essential structural elements of the body), necessitates reinforcement across the entire body, even for vehicles with shorter batteries. All vehicles in the range are penalized in terms of weight and cost.

[0010] The present invention aims in particular to avoid these problems of the prior art.

[0011] To this end, it proposes a motor vehicle comprising on each side of the vehicle a longitudinal member disposed behind the floor of the passenger compartment receiving below a traction battery of this vehicle, this longitudinal member having successively from the floor after a first angle turned upwards an inclined intermediate part, then after a second angle turned downwards a final part, the vehicle comprising under each intermediate part of the longitudinal member a rear support which supports the rear end of the traction battery, this vehicle being remarkable in that each support includes a lateral reinforcement plate which is fixed on one side of the rear longitudinal member covering its second angle.

[0012] An advantage of this motor vehicle is that for a long traction battery reaching the level of the first angle of the rear longitudinal members, the existing support receiving the rear end of this battery is used on each side of the vehicle to obtain with this same part the lateral reinforcement plate which is fixed on the side of the second angle of the longitudinal member.

[0013] Without additional parts, for vehicles including a long battery coming to the level of the rear longitudinal members, the lateral reinforcement plate is obtained which in the event of a major rear impact will limit an additional bending of the second angle of these longitudinal members, and consequently of the first angle, which prevents a denting of the passenger compartment floor located at this level and protects the battery located just below.

[0014] In the case of a vehicle with a short battery, the rear-mounted long battery supports, including their reinforcing side plate, are not used. A greater deformation of the side members causing the passenger compartment floor to sink is not a problem for the battery, which is not located below these side members.

[0015] The motor vehicle according to the invention may further comprise one or more of the following characteristics, which may be combined with each other.

[0016] Advantageously, the side reinforcement plate covers the second spar angle.

[0017] Advantageously, each rear support has a flat face for attaching the traction battery.

[0018] In this case, advantageously each rear support forms a closed box comprising the flat face which extends into a rear face and into side faces which rise up to be fixed at the top to the longitudinal member.

[0019] Advantageously, the side reinforcement plate has curves along two directions which provide support over its entire surface on the side of the longeron.

[0020] Advantageously, the side reinforcement plate is attached to the rear support.

[0021] In this case, advantageously the side reinforcement plate has a higher thickness or material strength than the rear support.

[0022] The invention also relates to a range of electric and hybrid motor vehicles, remarkable in that it includes electric vehicles comprising any of the preceding characteristics, having rear supports, and hybrid vehicles having a shorter traction battery, not including a rear support.

[0023] Advantageously, all vehicles in the range have rear side members with identical shape and material characteristics.

[0024] The invention will be better understood and other features and advantages will become more apparent upon reading the following description given by way of example, with reference to the accompanying drawings in which:

[0025] [Fig-1] is a view from below of the rear part of a vehicle according to the invention;

[0026] [Fig.2] is a side view of this rear part shown from the outside of the vehicle ;

[0027] [Fig.3] is an underside view of the bare body of this vehicle;

[0028] [Fig.4] is a side view diagram showing the deformations of the rear longitudinal member in case significant impact on the rear of the vehicle;

[0029] [Fig. 5] is a detail view of the battery support of this vehicle; and

[0030] [Fig.6] is a bottom view of the rear part of a vehicle of the same range including a short-range traction battery.

[0031] Throughout the document, the upper or top sides are relative to the vertical axis of a vehicle placed on a horizontal ground, and the front direction is the forward direction of the vehicle.

[0032] Figures 1, 2 and 3 show a traction battery of an electric vehicle 2 forming a flat assembly located under the floor of the passenger compartment 16, between two side rails of the vehicle's underbody 4. A rear axle 8 forms a rigid structure fixed below two rear rails 12, comprising on each side a suspension triangle 10 supporting a rear wheel 6.

[0033] Each rear longitudinal member 12 has a central axis A comprising successively a horizontal front part 20 fixed directly to the rear end of a rocker panel 4, then after a first angle 22 an intermediate part inclined upwards 24, then after a second angle 26 a final rear part 28 substantially horizontal, receiving at its end a cross member supporting the rear bumper 14.

[0034] A rear battery support 30 formed by a sheet metal fixed under the inclined intermediate part 24 of the rear longitudinal member 12, has a horizontal flat face 32 having holes 34 receiving battery clamping screws 2, framed by vertical edges comprising lateral faces 36 fixed at the top on the sides of the rear longitudinal member 12, and a rear face 38 ending with a folded edge 40 which is fixed flat under this rear part.

[0035] Figures 2 and 4 show an impact F on the rear end of the spar 12 which tends to move forward its final part 28 with a greater inclination of the intermediate part 24, which gives both an uphill H of the second angle 26, and a downhill B of the first angle 22 which tends to strike the top of the battery 2.

[0036] Fig. 5 shows the rear support 30 forming a small closed box having in side view a triangular section, allowing the battery 2 to be fixed under its horizontal flat face 32 which is strongly held under the intermediate part of the rear longitudinal member 24 thanks to its lateral faces 36 and its rear face 38 fixed on this part.

[0037] A reinforcing side plate 42 forms an elongated, substantially flat sheet metal strip, having a lower edge that is fixed to the upper part of the lateral support face 36 facing inwards towards the vehicle. The reinforcing plate 42 has curves in two dimensions that allow it to be fixed to the side of the rear longitudinal member 12, remaining fully supported over its entire surface to obtain maximum rigidity, covering the second corner 26 with an overlap over more than half of the intermediate portion 24 and over the final rear portion 28.

[0038] Advantageously the side reinforcement plate 42 is attached by welding to the rear support 30, which allows for the selection of a thickness or a material strength higher than that of this support.

[0039] For a significant rear impact on the vehicle delivering a longitudinal force F on the end of the rear longitudinal member 12, a much greater blocking of the folding of the second angle 26 is obtained, which resists better thanks to the reinforcement plate 42. This limits the rise H of the second angle 26, the intermediate part of the longitudinal member 24 retaining substantially its inclination, and the descent B of the first angle of the longitudinal member 22 is significantly reduced.

[0040] By modifying a single part of the vehicle formed by the rear support 30 including the side reinforcement plate 42, a significant reinforcement of each rear longitudinal member 12 is obtained in a simple and effective manner, which protects the battery in the event of a rear impact.

[0041] Figure 6 shows a hybrid vehicle from the same modular vehicle range, comprising similar bodies housing a traction battery 2 with a shorter rear section that has a reduced load capacity. The available space behind the battery 2 is occupied by a fuel tank 50 and an exhaust silencer 52, which are necessary for a hybrid vehicle equipped with an internal combustion engine.

[0042] The hybrid vehicle's body has the same rear side members 12, but since the battery 2 is shorter, the rear battery support 30 is not used. However, in the event of a rear-end collision with this vehicle, a downward movement B of the first angle of the side member 22 can occur without damaging the battery 2, which is no longer below this angle, thus posing no safety problems for this battery.

[0043] This results in a modular range of vehicles that can incorporate the same rear side members 12, with identical shapes, sheet metal thickness, and steel quality. This allows for optimized mass production of the vehicle bodies in the range, resulting in a minimum weight for the hybrid version, which does not require unnecessary reinforcement, and a reduced cost.

Claims

Demands

1. Motor vehicle comprising on each side of the vehicle a longitudinal member (12) disposed behind the floor of the passenger compartment (16) receiving below a traction battery of this vehicle (2), this longitudinal member (12) having successively from the floor (16) after a first angle (22) turned upwards an inclined intermediate part (24), then after a second angle turned downwards (26) a final part (28), the vehicle comprising under each intermediate part of longitudinal member (24) an added rear support (30) which supports the rear end of the traction battery (2), characterized in that each added support (30) has a lateral reinforcement plate (42) which is fixed on one side of the rear longitudinal member (12).

2. Motor vehicle according to claim 1, characterized in that the side reinforcement plate (42) covers the second side member angle (26).

3. Motor vehicle according to claim 1 or 2, characterized in that each rear support (30) has a flat face (32) for attaching the traction battery (2).

4. Motor vehicle according to claim 3, characterized in that each rear support (30) forms a box comprising the flat face (32) which extends into a rear face (38) and into side faces (36) which rise up to be fixed at the top to the longitudinal member (12).

5. Motor vehicle according to any one of the preceding claims, characterized in that the side reinforcement plate (42) has curves in two directions which provide support over its entire surface on the side of the longitudinal member (12).

6. Motor vehicle according to any one of the preceding claims, characterized in that the side reinforcement plate (42) is attached to the rear support (30).

7. Motor vehicle according to claim 6, characterized in that the side reinforcement plate (42) has a higher thickness or material strength than that of the rear support (30).

8. A range of electric and hybrid motor vehicles, characterized in that it comprises electric vehicles according to any one of the preceding claims, having

9. rear supports (30), and hybrid vehicles with a shorter traction battery (2), not including rear support. Range of motor vehicles according to claim 8, characterized in that all vehicles in the range have rear side members (12) having identical shape and material characteristics.

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