LIGHTWEIGHT ELECTRIC VEHICLE WITH SIDE BATTERY PROTECTION PANEL FIXED IN A TUBULAR CHASSIS

Abstract

Electric vehicle comprising a tubular chassis having a lower plane (2) comprising side rails (16), a seat equipped with a tubular frame (28) supporting its seat, and comprising a traction battery (32) fixed on the lower plane of the chassis (2), which has between this seat frame (28) and the side rail (16) a face facing the outside of the vehicle, this vehicle comprising on the external face of the battery (32) an energy absorption panel (50) which is arranged between the side rail (16) and the seat frame (28), and inside the external edges of this side rail (16) and this seat frame (28). Figure 3

Description

Title of the invention: LIGHT ELECTRIC VEHICLE WITH SIDE BATTERY PROTECTION PANEL FIXED IN A TUBULAR FRAME

[0001] The present invention relates to a light electric vehicle comprising a tubular chassis supporting a traction battery equipped with lateral protection.

[0002] A known type of light electric vehicle comprising two rear drive wheels and a single front wheel in order to limit its mass and size, intended for urban deliveries, comprises a front driver's cabin, and a rear loading platform directly receiving the goods or supporting a box to protect them inside.

[0003] The chassis of the vehicle comprises a lower level tubular plane extending under the cabin, comprising side members, and an upper level tubular plane which supports the platform, receiving below the rear axle with its motorization. The traction battery of the vehicle is fixed at the front in the cabin under the driver's seat, between the lower tubular plane which supports it and a tubular seat frame arranged in the plane of the platform, these two planes forming below and above a rigid protection of this battery.

[0004] In some of these vehicles the seat is shifted towards the left side of the vehicle in order to free up space in the cabin on the other side, at the edge of this seat, to receive in particular a handbrake lever fixed to the floor.

[0005] Furthermore, it is known to adjust the traction battery under the entire seat in the transverse direction of the vehicle in order to benefit from a large volume of energy storage ensuring the autonomy of the vehicle, this battery then has an external lateral face which is close to the edge of the bodywork.

[0006] In the event of a lateral impact on the side of the vehicle occurring at an intermediate height between the two rigid planes formed by the side rail of the lower plane and the plane of the seat frame, corresponding for example to an impact on a safety barrier arranged at this height, the chassis does not offer protection to protect the battery. In the event of an impact on the traction battery which deforms it, in particular for lithium-ion batteries, there is then in particular a risk of fire.

[0007] Furthermore, a known type of lateral protection for a traction battery, presented in particular by document FR-A1-3063458, comprises an energy absorption panel inserted between the side of the battery and an external lateral spar, which receives this energy to absorb it at least in part in the event of deformation of the spar.

[0008] Another known type of lateral protection of a traction battery, presented in particular by document FR-A1-3110115, comprises a substantially horizontal flat structure, arranged between an external side member and a battery box, having ribs which are oriented in the transverse direction of the vehicle. In the event of a significant lateral impact resulting in deformation of the side member, in particular an impact against a post, the transverse ribs of the flat sheet having a resistance along their length absorb energy during their deformation which reduces or eliminates the impact on the battery box.

[0009] However, these two known types of protection are intended to be arranged between an external spar and the battery, and intervene after the spar has received the impact when it deforms, in order to absorb energy without directly receiving the impact.

[0010] In particular for light and compact vehicles, comprising only tubular chassis elements above and below the battery, it is not possible to add an additional side member at the level of this battery which would increase the mass of the vehicle and its lateral size.

[0011] The present invention aims in particular to avoid these problems of the prior art.

[0012] To this end, it proposes an electric vehicle comprising a tubular chassis having a lower plane comprising lateral side members, a seat equipped with a tubular frame supporting its seat, and comprising a traction battery fixed on the lower plane of the chassis below the seat frame, which has a lateral face facing the outside of the vehicle, this vehicle being remarkable in that it comprises an energy absorption panel covering at least in part the lateral face of the battery, inserted vertically between the lateral side member and the seat frame, which is arranged inside the outer edges of the lateral side member and of this seat frame.

[0013] An advantage of this vehicle is that by using the vertical space between the lateral side member of the lower plane of the chassis and the tubular seat plane, and transverse space between the outer lateral face of the battery and the outer edges of the chassis, the space is best used to receive the energy absorbing material in order to ensure maximum protection of the battery side in the event of the vehicle impacting a rigid element inserted between these two planes.

[0014] In particular, available space is used without adding width at the two tubular planes, which is important for a light and compact vehicle.

[0015] The 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 energy absorption panel comprises a rigid foam.

[0017] Advantageously, the energy absorption panel comprises a rigid material forming alveoli.

[0018] In this case, advantageously the cells comprise thin walls formed by a plastic or metallic material.

[0019] In addition, the cells may have a honeycomb shape.

[0020] In this case, advantageously the honeycomb-shaped cells are oriented in the transverse direction of the vehicle.

[0021] Advantageously, the energy absorption panel comprises an absorption material which is arranged between two pressure distribution skins.

[0022] Advantageously, the energy absorption panel covers, in addition to the battery, electronic control boxes which are fixed above this battery.

[0023] In particular, the vehicle may be a light vehicle comprising two rear drive wheels and a single front wheel.

[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.l] is a side view of a light vehicle according to the prior art, shown without the bodywork;

[0026] [Fig.2] shows the side of this vehicle after a side impact at the battery level traction;

[0027] [Fig.3] is a partial view of the left side of a light vehicle according to the invention including a battery protection panel;

[0028] [Fig.4] is a cross-sectional diagram along a vertical plane of this vehicle at level of the protection panel; and

[0029] [Fig.5] shows an example of protective panels comprising a material honeycomb absorption, the upper or top direction is relative to a vehicle placed on horizontal ground, the transverse direction is perpendicular to the longitudinal axis of the vehicle, the outer side EXT being turned towards the outside of the vehicle, and the front direction AV is relative to the direction of travel of the vehicle.

[0030] [Fig.l] shows a light motor vehicle comprising a tubular chassis having a lower plane 2 comprising lateral side members 16 extending forwards under the cabin 4, and behind this cabin an upper plane 8 receiving above a loading platform 10. The rear part of the side members 14 rises, coming under the upper tubular plane 8, to receive below the rear axle comprising the two rear wheels 12 which are driven.

[0031] The cabin 4 is framed by two front uprights 20 and two rear uprights 22, which are connected by crosspieces to ensure rigidity. A covering not shown, comprising a windshield, covers the tubular shape of the cabin 4 to protect the driver.

[0032] A driver's seat 24 comprises a seat 26 resting on a tubular frame of support 28 forming a rectangle arranged horizontally, fixed towards the rear to the rear cabin uprights 22 and towards the front by vertical feet 30 joining the lower chassis plane 2. The seat 24 leaves on its right side a free transverse space which receives a handbrake lever fixed to the ground, its left side arriving near the edge of the tubular chassis, between the front upright 20 and the rear upright 22, a little set back from a lateral side member 16 of the lower chassis plane 2 which connects these two uprights.

[0033] A power supply battery for the electric traction machine of the vehicle 32 fixed to the lower chassis plane 2, covers the entire width of the seat 24, and a large part of its length in the longitudinal direction of the vehicle. A free space above the battery 32, under the seat cushion 26 and its seat support frame 28, receives electronic control boxes for the motorization 34.

[0034] An electrical harness 36 runs from the lower left side member 16, at the front of the seat 24, to mount under the seat support frame 28 in order to supply the electronic boxes 34.

[0035] Motor vehicles are subject to standardized impacts that may occur in the event of an accident, intended to improve their design to ensure safety.

[0036] [Fig.2] shows an impact F on the left side of the vehicle at the level of the cabin 4, by a safety barrier 40 having a height which fits between the lower lateral side member 16 and the tubular seat support frame 28. The barrier 40 only encounters as a resistant element the base of the rear cabin pillar 22, which is pushed in due to insufficient rigidity to contain the impact developing in this example a maximum force of 17.5kN.

[0037] A depression of the base of the rear upright 22 is obtained which is sufficient for the barrier 40 to reach the left lateral face of the battery 32, deforming it. In addition, the rising part of the electrical harness 36 is then pressed with a risk of pinching on the lateral face of the battery 32.

[0038] There is then damage to the battery representing an expensive element, which must be changed if the vehicle is repairable. In addition, the pinching of the electrical harness 36 leads to risks of short circuit, and the deformation of the battery 32 to risks of fire starting, in particular for a lithium-ion type battery.

[0039] Figures 3 and 4 show a protective panel 50 providing energy absorption, arranged flat on the left side face of battery 32, which vertically covers the entire height between the lower side member 16 and the seat support frame 28, and which transversely occupies substantially the entire width between this side face of battery and the external body shape 52.

[0040] The protective panel 50 may comprise any type of absorbent material energy when it is crushed, such as a rigid foam, in particular a compact polyurethane foam. It can also contain a plastic or metallic material, in particular comprising cells separated by thin walls which gradually deform in the event of an impact. The cells can also be additionally filled with a rigid foam.

[0041] Advantageously, the protective panel 50 comprises two outer skins receiving the energy-absorbing material between them, which are sufficiently rigid to distribute the pressure over a larger surface area of ​​this intermediate material.

[0042] [Fig. 5] shows a panel 50 comprising two rigid outer skins 54 which are connected by a honeycomb structure 56 having cells oriented in the transverse direction of the vehicle. In particular, the honeycomb structure 56 can be made of a plastic material, such as polypropylene, or aluminum, these materials having a good energy absorption capacity for crushing of the cells along their length.

[0043] Generally speaking, the protective panel 50 achieves both energy absorption during its crushing, and by its width a distribution of this energy over a larger surface area of ​​the battery side face 32 which allows its box to resist better. In practice, for the same impact presented [Fig.2], calculations show that it is possible to obtain on the battery side face 32 a maximum force of less than 2.5 kN, which reduces the force by a factor greater than 7.

[0044] Effective protection against lateral impacts occurring in particular at a critical height, opposite the battery 32, is thus obtained by a simple and economical means, comprising the addition of a protective panel 50 fitted between the existing tubes of the tubular chassis, without modifying them.

Claims

Claims

1. Electric vehicle comprising a tubular chassis having a lower plane (2) comprising side rails (16), a seat (24) equipped with a tubular frame (28) supporting its seat (26), and comprising a traction battery (32) fixed on the lower plane of the chassis (2), which has between this seat frame (28) and the side rail (16) a face facing the outside of the vehicle, characterized in that it comprises on the external face of the battery (32) an energy absorption panel (50) which is arranged between the side rail (16) and the seat frame (28), and inside the external edges of this side rail (16) and this seat frame (28).

2. Electric vehicle according to claim 1, characterized in that the energy absorption panel (50) comprises a rigid foam.

3. Electric vehicle according to claim 1 or 2, characterized in that the energy absorption panel (50) comprises a rigid material forming cells.

4. Electric vehicle according to claim 3, characterized in that the cells comprise thin walls formed by a plastic or metallic material.

5. Electric vehicle according to claim 4, characterized in that the cells have a honeycomb shape.

6. Electric vehicle according to claim 5, characterized in that the honeycomb-shaped cells are oriented in the transverse direction of the vehicle.

7. An electric vehicle according to any preceding claim, characterized in that the energy absorbing panel (50) comprises an absorbing material which is disposed between two pressure distributing skins (54).

8. Electric vehicle according to any one of the preceding claims, characterized in that the energy absorption panel (50) covers in addition to the battery (32) electronic control boxes (34) which are fixed above this battery (32).

9. Electric vehicle according to any one of the preceding claims, characterized in that it is a light vehicle comprising two rear drive wheels (12) and a single front wheel (6).

Images