MOTOR VEHICLE WITH TRACTION BATTERY SUPPORTS ARRANGED IN FRONT OF THE REAR SIDE MEMBERS

Abstract

Motor vehicle comprising on each side of the vehicle a side member (12) arranged behind the floor of the passenger compartment receiving underneath a traction battery of this vehicle (2), this side member (12) having successively from the floor 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 side member (24) an added rear support (30) which supports the rear end of the traction battery (2), each added support (30) comprising a lateral reinforcement plate (42) which is fixed on one side of the rear side member (12). Figure 2

Description

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

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

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

[0003] Each side member is extended by a rear member comprising successively after a first angle an inclined intermediate part which rises, then after a second angle a substantially horizontal final rear part supporting the floor of the trunk of the vehicle which is at a higher level than that of the passenger compartment. The rear members form a raised and resistant structure supporting the rear axle of the vehicle underneath.

[0004] Motor vehicles are subjected to standardized impacts enabling passenger safety to be checked, including in particular a rear impact offset to one side of the vehicle which compresses a rear side member. Furthermore, during these impacts, it is necessary to limit the deformations of the traction battery box arranged in front of the rear side members, in order to avoid in particular damage to the electrochemical cells arranged inside, which could cause a fire to start.

[0005] Generally speaking, in the event of a significant rear impact on the vehicle, it is possible to obtain a forward displacement of the final part of the side member, causing a straightening of the intermediate part which tilts more strongly, giving a more pronounced bending of the two successive angles. The straightening of the first angle can cause a depression of the floor arranged at this level, and a deformation of a battery box fixed just below.

[0006] The vehicle according to the prior art has on the second corner of the rear side 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 side 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 specific parts, including their manufacture and their fixing to the vehicle body, which poses problems of additional operating time and higher costs.

[0008] Furthermore, as a variant, it is known to increase the thickness of the rear side member sheets and the strength of the steel used, which gives a greater mass to the vehicle, and higher costs, in particular with high-strength steels which are expensive.

[0009] However, in the case of a range of vehicles having traction batteries of different lengths, some of which have a shorter rear end that is not at risk of being damaged by this type of rear impact, significant standardization in the manufacture of bodies comprising the same side members, representing essential elements of the structure of the body, leads to reinforcement across all of these bodies, even for vehicles having batteries that are shorter. All vehicles in the range are penalized for mass and costs.

[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 side member arranged behind the floor of the passenger compartment receiving underneath a traction battery of this vehicle, this side member having successively from the floor after a first angle facing upwards an inclined intermediate part, then after a second angle facing downwards a final part, the vehicle comprising under each intermediate part of the side member an added rear support which supports the rear end of the traction battery, this vehicle being remarkable in that each added support comprises a lateral reinforcement plate which is fixed on one side of the rear side member covering its second angle.

[0012] An advantage of this motor vehicle is that for a long traction battery arriving at the level of the first angle of the rear side 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 side reinforcement plate which is fixed on the side of the second angle of the side member.

[0013] Without any additional part, for vehicles comprising a long battery coming at the level of the rear side members, the side reinforcement plate is obtained which, in the event of a significant rear impact, will limit further bending of the second angle of these side members, and consequently of the first angle, which prevents the passenger compartment floor located at this level from sinking and protects the battery located just below.

[0014] In the case of a vehicle comprising a short battery, the long battery rear supports including their side reinforcement plate are not used, a greater deformation of the side members causing a sinking of the passenger compartment floor 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 side member angle.

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

[0018] In this case, advantageously each rear support forms a closed box comprising the flat face which is extended by a rear face and by lateral faces which rise to be fixed in the upper part to the side member.

[0019] Advantageously, the side reinforcement plate has curvatures in two directions which provide support over its entire surface on the side of the spar.

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

[0021] In this case, advantageously the side reinforcement plate has a thickness or a resistance of the material greater than that of the rear support.

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

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

[0024] The invention will be better understood and other characteristics and advantages will appear more clearly on reading the description below given by way of example, with reference to the appended drawings in which:

[0025] [Fig-1] is a bottom view 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 a bottom view of the bare body of this vehicle;

[0028] [Fig.4] is a side diagram showing the deformations of the rear spar in the event of significant impact on the rear of the vehicle;

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

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

[0031] Throughout the document the upper or top sides are relative to the vertical axis of a vehicle placed on horizontal ground, the forward 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 arranged under the floor of the passenger compartment 16, between two side rails of the underbody of the vehicle 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 side member 12 has a central axis A comprising successively a horizontal front part 20 fixed directly to the rear end of a side member of the underbody 4, then after a first angle 22 an upwardly inclined intermediate part 24, then after a second angle 26 a substantially horizontal final rear part 28, 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 side member 12, comprises a horizontal flat face 32 having holes 34 receiving screws for tightening the battery 2, framed by vertical edges comprising lateral faces 36 fixed in the upper part on the sides of the rear side member 12, and a rear face 38 ending in 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 side member 12 which tends to move its final part 28 forward with a greater inclination of the intermediate part 24, which gives both a rise H of the second angle 26, and a descent 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 comprising in side view a triangular section, allowing fixing of the battery 2 under its horizontal flat face 32 which is strongly held under the intermediate part of the rear side member 24 thanks to its lateral faces 36 and its rear face 38 fixed on this part.

[0037] A side reinforcement plate 42 forms an elongated strip of substantially flat sheet metal, having a lower edge which is fixed to the upper part of the lateral support face 36 arranged towards the inside of the vehicle. The reinforcement plate 42 has curvatures in two dimensions which allow it to be fixed to the side of the rear side member 12 while remaining completely supported on it over its entire surface to obtain the best rigidity, by covering the second angle 26 with an overhang over more than half of the intermediate part 24 and on the final rear part 28.

[0038] Advantageously, the side reinforcement plate 42 is attached by welding to the rear support 30, which makes it possible to choose a thickness or a resistance of the material 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 side member 12, a much greater blocking of the folding of the second angle 26 is obtained, which resists better thanks to the reinforcing plate 42. This limits the rise H of the second angle 26, the intermediate side member part 24 substantially retaining its inclination, and the descent B of the first side member angle 22 which is significantly reduced.

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

[0041] [Fig. 6] shows a hybrid vehicle from the same modular range of vehicles, comprising similar bodies receiving a traction battery 2 with a shorter rear part which has a reduced load capacity. The available space left 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 a thermal engine.

[0042] The body of the hybrid vehicle 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 impact on this vehicle, a descent B of the first side member angle 22 can be done without damaging the battery 2, which is no longer below this angle, which does not pose any safety problems for this battery.

[0043] This results in a modular range of vehicles which can have the same rear side members 12, with shapes, sheet thickness and steel quality which remain identical. This allows for the optimization of large-scale production of vehicle bodies in the range, with a minimum mass for the hybrid version which does not have unnecessary reinforcement, and a reduced cost.

Claims

Claims

1. Motor vehicle comprising on each side of the vehicle a side member (12) arranged behind the floor of the passenger compartment (16) receiving underneath a traction battery of this vehicle (2), this side 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 side member (24) an added rear support (30) which supports the rear end of the traction battery (2), characterized in that each added support (30) comprises a lateral reinforcement plate (42) which is fixed on one side of the rear side 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) comprises a flat face (32) for fixing 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 is extended by a rear face (38) and by lateral faces (36) which rise to be fixed in the upper part to the side member (12).

5. Motor vehicle according to any one of the preceding claims, characterized in that the side reinforcement plate (42) has curvatures in two directions which provide support over its entire surface on the side of the side 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 reinforcing side plate (42) has a thickness or material strength greater than that of the rear support (30).

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

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