Electric vehicle underbody protection device.

Abstract

The invention relates to a rear axle protection device (1) designed to be fitted to the body (2) of a motor vehicle, the device (1) having a main part (3) forming a fairing plate (4) designed to be fixed to the body (2) and to cover at least part of the rear axle (5), the plate (4) extending between an axle crossmember (6a) and a mounting crossmember (7) designed to allow the attachment of a battery, the device (1) comprising a reinforcing part (11) designed to form a spacer between the rear axle crossmember (6a) and the mounting crossmember (7) in order to maintain a minimum distance (M) between the axle crossmembers (6a) and (7) in the event of a rear impact suffered by the vehicle equipped with the device (1) which could cause the axle crossmember (6a) and the mounting crossmember (7) to come closer together. (Figure 3)

Description

Title of the invention: Electric vehicle underbody protection device.

[0001] The technical field relates to rear axle protection devices, vehicle bodies equipped with such a protection device and vehicles having such a body.

[0002] Passenger safety is a major concern for automobile manufacturers, who continually strive to improve it. To ensure passenger safety, vehicles are subjected to various standardized procedures simulating impacts against a rigid obstacle. These standardized procedures are described, for example, by the U.S. National Highway Traffic Safety Administration (NHTSA), which is responsible for road safety and vehicle regulations, or by the international organization Euro NCAP.

[0003] Among these procedures, some combine several types of simulations of impacts against various barriers affecting the rear of the vehicle at various heights, referred to as rear impacts. In some rear impacts, the barrier is likely to penetrate the vehicle structure and cause the rear axle beams to recoil. Such an impact is, for example, published by the U.S. National Security Administration under the reference AR FMVSS301.

[0004] In this context, many motor vehicles are equipped with a battery located under the floor and an electric motor, positioned between the rear axle crossmembers, powered by the battery via a high-voltage cable. Such a cable usually runs between the vehicle floor and the rear axle crossmembers. However, if the rear axle crossmembers are pushed back following a sufficiently significant rear-end impact, the high-voltage cable is liable to be crushed between the floor and a rear axle crossmember, particularly due to a rotational or twisting movement of the entire rear axle assembly.

[0005] Such crushing of the cable is synonymous with unacceptable electrical risks, and it is necessary to demonstrate that the cable is not at risk of being crushed during such an electric shock. To this end, automobile manufacturers provide sufficient space between the floor and the axle beam, on the order of 45 mm to 50 mm, to allow the passage of a cable with a diameter of approximately 20 mm. However, certain vehicles, particularly those intended for a segment of the North American market, must also comply with certain operating constraints involving vehicle travel on unpaved tracks, which necessitate additional underbody protection screens to protect the front and rear axles. Such protective screens have considerable thicknesses, on the order of 4.5 mm, which reduce the available space for the high-voltage cable. Furthermore, experience shows that certain specific rear-impact tests, notably the FMVSS301 rear-impact test, can cause an increased risk of rotation or twisting of the rear axle, and therefore crushing of the high-voltage cable.

[0006] Thus, there is a need for a solution to reduce the risk of crushing a high-voltage cable between the floor and the rear axle of a vehicle in the event of a specific rear-end collision.

[0007] The present invention aims to overcome the problems described above. In this technical context, one objective of the present invention is to provide a protective device intended to replace a protective screen on the underbody, making it possible to limit or prevent the crushing of a high-voltage cable during a rear-end collision, regardless of the type of collision.

[0008] To this end, the present invention relates to a rear axle protection device designed to equip a body of a motor vehicle, the device having a main part forming a fairing plate designed to be fixed to the body and to cover at least in part the rear axle of the vehicle on which the device is fixed, the plate extending between an axle crossmember and a mounting crossmember designed to allow the attachment of a motor battery, the device further comprising at least one reinforcement part, each designed to form a spacer between the rear axle crossmember and the mounting crossmember in order to maintain a predefined minimum distance between the axle and mounting crossmembers in the event of a rear impact suffered by the vehicle equipped with the protection device likely to cause the axle crossmember and the battery mounting crossmember to come closer together.

[0009] The invention also relates to a motor vehicle body comprising a rear axle supported by at least one rear axle crossmember and a mounting crossmember for a motor battery, the body further comprising a device according to the invention fixed to the body and extending between the rear axle crossmember and the mounting crossmember.

[0010] The invention finally relates to a motor vehicle having a body according to the invention.

[0011] Thus, the protective device according to the invention makes it possible to replace a conventional protective screen to form the underbody of a vehicle according to the invention. The main part provides conventional underbody protection, while the reinforcing part ensures a predefined minimum distance between the mounting crossmember and the rear axle crossmember, to limit the possibility of rotation or twisting of the rear axle. The rear axle cannot undergo rotation. or significant twisting, the clearance for the high-voltage cable between the rear axle and the floor is maintained, and the risk of cable crushing is limited or eliminated. Thus, the protective device according to the invention makes it possible to obtain a motor vehicle with underbody protection capable of passing all rear impact tests, including those specific to off-road driving.

[0012] According to one embodiment of the device, each reinforcement part is made of the same material as the fairing plate.

[0013] Advantageously, each reinforcing part forms a rib extending along a longitudinal axis of the vehicle, when the device is fixed to the body of the vehicle, the rib extending between a first end, designed to be positioned opposite the rear axle crossmember, and a second end, designed to be positioned opposite the fixing crossmember.

[0014] Advantageously still, the first and second ends of the rib are arranged at a distance from the respective cross members.

[0015] According to one possibility, the device is formed by stamping sheet metal.

[0016] According to one embodiment, the vehicle body includes a high-voltage cable extending at least partially between a floor of the body and the rear axle.

[0017] Advantageously, the high-voltage cable is designed to connect a rear axle motor and a battery attached to the mounting crossmember.

[0018] According to one possibility of the motor vehicle, a motor battery is attached to the mounting crossmember.

[0019] The invention will be better understood upon reading the following detailed description, given solely by way of non-limiting example and made with reference to the accompanying drawings in which:

[0020] [Fig-1] [Fig.1] represents a view from below of a motor vehicle according the invention;

[0021] [Fig.2] [Fig.2] represents a perspective view of a protective device according to the invention equipping the vehicle of the [Fig.1];

[0022] [Fig.3] [Fig.3] represents a longitudinal cross-sectional view of the vehicle along an axis AL of [Fig.1], showing the reinforcement part of the protection device of [Fig.2];

[0023] [Fig.4] [Fig.4] represents a schematic cross-sectional view of [Fig.3] in the case of rear impacts suffered by the vehicle in [Fig.1].

[0024] In these figures, the same references are used to designate the same elements.

[0025] A rear axle protection device 1 according to the invention, illustrated in the figures, is designed to equip a body 2 of a motor vehicle according to the invention, illustrated in [Fig. 1]. The protective device 1, when fixed to the casing 2, forms part of the base of the casing 2.

[0026] The device 1 has a main part 3 forming a fairing plate 4 designed to be fixed to the body 2 and to cover at least part of the rear axle 5 of the vehicle, illustrated in [Fig.1], on which the device 1 is fixed.

[0027] As illustrated in [Fig. 3], the plate 4 extends between a landing gear crossmember 6a and a mounting crossmember 7, designed to allow the attachment of a motor battery 8, illustrated in [Fig. 1]. In this case, the rear axle 5 includes an electric motor 9, partially illustrated in [Fig. 3], held by two landing gear crossmembers 6a, 6b, framing the electric motor 9. The device 1 extends from the landing gear crossmember 6a, positioned behind the body 2, and completely covers the other landing gear crossmember 6b located between the landing gear crossmember 6a and the mounting crossmember 7. As illustrated in [Fig. 3], the plate 4 forms a groove 10 in which the landing gear crossmember 6a is partially housed when the device 1 is attached to the body 2.

[0028] The device 1 further includes at least one reinforcement part 11, illustrated in Figures 2 to 4, each designed to form a spacer between the rear axle crossmember 6a and the fixing crossmember 7, in order to maintain a predefined minimum spacing EM between the axle crossmembers 6a and fixing crossmember 7 in the event of a rear impact, suffered by the vehicle equipped with the protective device 1, which could cause the axle crossmember 6a and the battery fixing crossmember 7 to come together.

[0029] As illustrated in Figures 2 to 4, the reinforcing part 11 is formed from the same material as the fairing plate 4. In the example shown in the figures, the device 1 is formed by stamping a sheet of metal.

[0030] As illustrated in Figures 2 and 3, the reinforcing portion 11 forms a rib 12 extending along a longitudinal axis AL of the vehicle, illustrated in [Fig. 1], when the device 1 is attached to the vehicle body 2. The rib 12 then extends between a first end 13a, designed to be positioned opposite the rear axle crossmember 6a, and a second end 13b, designed to be positioned opposite the mounting crossmember 7.

[0031] As illustrated in [Fig. 3], the first 13a and second 13b ends of the rib 12 are positioned at a distance from the respective sleepers. The distance is, for example, on the order of a few millimeters to a few centimeters. Alternatively, the first 13a and second 13b ends of the rib 12 are in contact with the train sleepers 6a and the fastening sleepers 7.

[0032] As illustrated in [Fig.4], the body 2 includes a high-voltage cable 14 intended to connect the electric motor 9 to the battery 8, attached to the mounting crossmember 7. The cable 14 extends at least in part between a floor 15 of the body 2 and the rear axle 5, above the axle crossmember 6b.

[0033] In order to allow the attachment of the protective device 1 to the case 2, the device 1 includes attachment means 16, such as screw tabs 17 or screw holes 18, illustrated in [Fig.2].

[0034] In the event of a rear impact, symbolized by the arrow in [Fig.4], suffered by the vehicle according to the invention and likely to bring the rear axle crossmember 6a closer to the fixing crossmember 7, the axle crossmember 6a, and possibly the axle crossmember 6b, move backward towards the fixing crossmember 7 until the first 13a and second 13b ends come into contact with the axle crossmembers 6a and fixing crossmember 7. The minimum spacing EM then corresponds to the distance between the first 13a and second 13b ends of the rib 12.

[0035] Thus, the protective device 1 according to the invention makes it possible to replace a conventional protective screen to form the underbody of a vehicle according to the invention. The main part 3 provides conventional underbody protection, while the reinforcing part 11 ensures a predefined minimum gap EM between the mounting crossmember 7 and the rear axle crossmember 6a, which limits the possibilities of rotation or twisting of the rear axle 5. Since the rear axle 5 cannot undergo significant rotation or twisting, the passage space for the high-tension cable 14 between the rear axle and the floor is preserved, and the risks of crushing the cable 14 are limited or eliminated.

[0036] The invention is not limited to the embodiment of the protection device described above, only by way of example, but other embodiments may be designed by a person skilled in the art without departing from the scope and extent of the present invention.

Claims

Demands

1. A rear axle protection device (1) designed to be fitted to a body (2) of a motor vehicle, the device (1) having a main part (3) forming a fairing plate (4) designed to be fixed to the body (2) and to cover at least part of the rear axle (5) of the vehicle on which the device (1) is fixed, the plate (4) extending between an axle crossmember (6a) and a mounting crossmember (7) designed to allow the attachment of a motor battery (8), the device (1) further comprising at least one reinforcing part (11),each designed to form a spacer between the rear axle crossmember (6a) and the mounting crossmember (7) in order to maintain a predefined minimum distance (EM) between the axle crossmembers (6a) and mounting crossmembers (7) in the event of a rear impact suffered by the vehicle equipped with the protective device (1) which could cause the axle crossmember (6a) and the mounting crossmember (7) to come closer together.

2. Device (1) according to claim 1, characterized in that each reinforcement part (11) comes from the same material as the fairing plate (4).

3. Device (1) according to claim 2, characterized in that each reinforcement part (11) forms a rib (12) extending along a longitudinal axis (AL) of the vehicle, when the device (1) is fixed to the body (2) of the vehicle, the rib (12) extending between a first end (13a), designed to be disposed opposite the rear axle crossmember (6a), and a second end (13b), designed to be disposed opposite the fixing crossmember (7).

4. Device (1) according to claim 3, characterized in that the first (13a) and second (13b) ends of the rib (12) are arranged at a distance from the respective cross members.

5. Device (1) according to any one of claims 1 to 4, characterized in that it is formed by stamping sheet metal.

6. Motor vehicle body (2) comprising a rear axle (5), supported by at least one rear axle crossmember (6a), and a mounting crossmember (7) for a motor battery (8), the body (2) further comprising a device (1) according to any one of claims 1 to 5 fixed to the body (2) and extending between the rear axle crossmember (6a) and the mounting crossmember (7).

7. Vehicle body (2) according to claim 6, characterized in that it comprises a high-voltage cable (14) extending at least in part between a floor (15) of the body (2) and the rear axle (5).

8. Vehicle body (2) according to claim 7, characterized in that the high-voltage cable (14) is designed to connect a motor (9) of the rear axle (5) and a battery (8) attached to the mounting crossmember (7).

9. Motor vehicle having a body (2) according to any one of claims 6 to 8.

10. Motor vehicle according to claim 9, characterized in that a motorization battery (8) is attached to the mounting crossmember (7).

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