WO2021219300A1

WO2021219300A1 - Vehicle with a multifunctional rear central crossmember

Info

Publication number: WO2021219300A1
Application number: PCT/EP2021/057708
Authority: WO
Inventors: Nicolas FARGEAS
Original assignee: Renault S.A.S; Nissan Motor Co., Ltd.
Priority date: 2020-04-28
Filing date: 2021-03-25
Publication date: 2021-11-04
Also published as: EP4143075A1; FR3109565A1

Abstract

The invention relates to an electric vehicle (1, 100) comprising a rear floor defined by two parallel longitudinal members (2, 3), the rear floor comprising a rear part (4) having a front zone (5) intended for the attachment of rear seats and for housing an electric battery (6), and a rear zone (7) intended to support a fuel tank (8) the two zones (5, 7) being separated from each other by a rear central crossmember (10) extending in a transverse direction Y of the vehicle (1, 100). According to the invention, the rear central crossmember (10) is in the form of three separate elements (15, 16, 17), including a straight central segment (15) and two lateral housings (16, 17), and the central segment (15) extends in a transverse direction Y of the vehicle, each of the two lateral housings (16, 17) being secured to one end of the central segment (15) and to a longitudinal member (2, 3).

Description

Title of the invention: Vehicle fitted with a multifunction rear central cross member.

The present invention relates to a vehicle provided with a multifunction rear central cross member.

For the purposes of the description, reference will be made to a direct orthonormal frame XYZ conventionally used in automotive design, in which the X axis designates the front-rear longitudinal direction of the vehicle, oriented towards the rear, the Y axis designates the transverse direction and is oriented to the right of the vehicle, the Z axis denotes the vertical direction, and is oriented upward.

Throughout the text which follows, the terms “rear central cross member” and “cross member” are equivalent.

Motor vehicles generally include a chassis configured to support all of the mechanical components and the vehicle body. The frame conventionally comprises two longitudinal side members and a plurality of transverse cross members arranged between said side members. A motor vehicle floor is supported by the frame and delimits the interior of the vehicle cabin. Generally, the floor of a motor vehicle includes a rear part called "rear floor", connected to a front part called "front floor".

The rear floor delimits the cabin of the rear passengers and comprises a front part delimiting a floor area intended to receive the feet of the passengers, also called a “foot cellar” and a rear part raised relative to the front part and delimiting a zone of floor intended to receive the seats of the second row of seats. This rear part includes a front area for fixing rear seats and housing an electric battery, and a rear area for supporting a fuel tank. These two zones are separated from each other by a rear central cross member extending in a horizontal and transverse direction Y of the vehicle and coming to be fixed to the two longitudinal side members. The term "horizontal" should be interpreted assuming that the vehicle is on level ground.

Such a rear central cross member is generally sized to protect the electric battery and the fuel tank against an accidental impact of the vehicle. vehicle against an external obstacle, said impact possibly being frontal, lateral or rear. In the event of such an impact, this cross member also allows good retention of the rear seats and limits the torsion of the vehicle.

But a drawback of this type of sleeper is that they are designed for only one type of vehicle having a floor having a well-defined geometry and dimensions. Indeed, if this vehicle were for example to be available in several versions or models, each time with a slight modification of the associated floor, the initially designed cross member would not be suitable for other models or versions, and a new central cross member would then have to be designed. rear adapted specifically to the new model considered.

A vehicle according to the invention has a rear central cross member having a character of universality, in particular being designed to be able to adapt to several types of flooring, while retaining its original properties.

The subject of the invention is a vehicle comprising a rear floor delimited by two parallel longitudinal members, said rear floor comprising a rear part having a front zone intended for fixing rear seats and housing an electric battery, and a rear zone intended in supporting a fuel tank, said two zones being separated from one another by a rear central cross member extending in a transverse direction Y of the vehicle.

According to the invention, the rear central cross member is made up of three distinct elements, including a rectilinear central segment and two side housings, the central segment extending in a transverse direction Y of the vehicle and each of the two side housings being secured at one end. of said central segment and to a spar. Usually, such a rear central cross member is made in one piece, and if the vehicle undergoes small structural modifications, said cross member would no longer be suitable, and a new one would then have to be manufactured. The principle of the invention is to make this cross member in three parts, including a constant central segment and two variable side boxes. Indeed, by dividing the rear central cross member into three parts, if the vehicle undergoes slight structural modifications, it would then be sufficient to keep the central segment and to adapt only the two side housings to these structural modifications. This division into three parts thus gives the rear central cross member a character of universality, because the segment central unit is retained, only the side boxes will be adapted to the new vehicle configuration. Preferably, each box is formed by an open wall delimiting an internal space, and can therefore be likened to a hollow part. The central segment is a thin wall extending along a transverse axis Y of the vehicle and whose cross section is profiled in particular to adapt to the environment of the vehicle in which it will be mounted, while having good rigidity. .

According to a possible characteristic of the invention, the two side cases are symmetrical. They thus have the same dimensions, while having a symmetrical profile. Each side case corresponds to the image of the other case reflected by a mirror.

According to a possible characteristic of the invention, the central segment and the two housings are metallic. This rear central cross member must have a certain robustness, in particular with regard to a collision of the vehicle against an external obstacle, because it must protect the electric battery and the fuel tank, and effectively retain the rear seats. A metal, which can for example be steel, effectively ensures this robustness.

According to a possible characteristic of the invention, the two side cases are fixed to the central segment by means of a fixing technique to be chosen from welding and screwing carried out with screws and nuts. It is important that this fixing is solid, because the two side boxes must not move or vibrate in relation to the straight central segment once the cross member has been fitted in the vehicle.

According to one possible characteristic of the invention, each box once it has been fixed in said vehicle comprises an upper face having fixing means making it possible to fix at least one functional element of said vehicle. A functional element can for example be constituted by an electric battery or by a rear axle. The presence of at least one fixing point on the cross member makes it possible to make this cross member multifunctional. Indeed, in addition to the aspect of robustness required for such a cross member with the aim in particular of containing the effects of an impact of the vehicle against an external obstacle, this cross member also plays the role of a relay support part to fix other parts. vehicle components. This aspect of robustness is thus exploited in order to be able to fix other elements of the vehicle.

According to a possible characteristic of the invention, each side casing comprises first fixing means cooperating with first fixing means complementary to the electric battery to fix said battery in the vehicle. Each side box of the rear central cross member serves as an anchoring point for the electric battery and thus provides a certain stability to said electric battery in the vehicle.

According to a possible characteristic of the invention, each side casing comprises second fixing means cooperating with second fixing means complementary to a rear axle for fixing said rear axle in the vehicle. Each side box of the rear central cross member serves as an anchoring point for the rear axle, and thus makes it possible to provide a certain stability to said rear axle in the vehicle.

According to a possible characteristic of the invention, each side box includes a pin for pre-positioning the electric battery in the vehicle. The rear central cross member also serves as a guide element for the battery in order to position it correctly in a housing provided in the rear part of the rear floor.

According to a possible characteristic of the invention, each housing comprises at least one stiffening rib extending parallel to the central segment. This rib increases the rigidity of the rear central cross member. Preferably, this rib extends the rectilinear central segment of said cross member.

According to a possible characteristic of the invention, each side casing has a first wall which forms part of the continuity of the central segment and a second wall which forms part of the continuity of the spar to which it is attached. In this way, each side box is fixed in the vehicle having surface contact with a spar and with one end of the central segment. This binding is therefore robust and clean, without creating an overhang.

A vehicle according to the invention has the advantage of having a universal rear central cross member making it possible to adapt to different platforms of the vehicle, with slight modifications to the two side boxes. It also has the advantage of having a multifunctional rear central cross member, playing both the role of a stiffening part to preserve certain first elements present in the vehicle in the event of an accidental impact against an external obstacle, and the role of a relay support part to secure certain other elements of said vehicle.

A detailed description of a preferred embodiment of a vehicle according to the invention is given below with reference to the following figures:

[Fig. 1] is a perspective view from below of a rear floor of a vehicle according to the invention,

[Fig. 2] shows a bottom view of a vehicle according to the invention,

[Fig. 3] is a view in longitudinal axial section of a rear floor of a vehicle according to the invention,

[Fig. 4] shows an enlarged area of the rear floor of figure 3,

[Fig. 5] is a perspective view of a rear central cross member of a vehicle according to the invention, said cross member being assembled,

[Fig. 6] shows an exploded perspective view of the cross member of FIG. 5,

[Fig. 7] shows a perspective view of the fixing points of an electric battery and a rear axle of a vehicle according to the state of the art,

[Fig. 8] is a perspective view of one end of a rear central cross member of a vehicle according to the invention,

[Fig. 9] shows a view from below of a vehicle according to the invention, which has been deformed following a side impact against a pole.

Referring to Figures 1 and 2, a vehicle 1 according to the invention is preferably a hybrid vehicle and comprises a rear floor, said rear floor comprising a rear part 4. This rear part 4 comprises a front area 5 intended in particular for fixing. rear seats and housing an electric battery 6, and a rear zone 7 intended in particular to support a fuel tank 8 and the passage of a rear axle 9. These two zones 5, 7 are separated from each other by a rear central cross member 10 extending in a transverse direction Y of the vehicle 1.

This rear part 4 of the rear floor is delimited by two longitudinal members 2, 3, parallel, extending in a longitudinal direction X of the vehicle. Referring to Figures 3 and 4, the electric battery 6 is housed in a compartment 11 of the front zone 5, which is delimited by a front wall 12 extending in a transverse and vertical plane YZ of the vehicle 1, and also called pareclose. The rear zone 7 houses the fuel tank 8 which is located in the immediate vicinity of the electric battery 6, a charger 30 for the electric battery 6 which is placed behind the fuel tank 8, and the rear axle 9 located under said charger 30 An exhaust line 13 extends along a longitudinal axis X of the vehicle passing under the front zone 5 and under the rear zone 7 of the rear part 4 of the rear floor. The rear central cross member 10 therefore separates the front zone 5 from the rear zone 7, and is located between the electric battery 6 and the fuel tank 8.

Assuming that the front zone 5 and the rear zone 7 are separated from each other by a fictitious wall extending in a transverse and vertical plane YZ of the vehicle 1, the rear central cross member 10 would be located in an upper part of said fictitious wall, just below a floor 14. In the passenger compartment of the vehicle 1, the rear central cross member 10 is capped by a rigid trim plate 31, placed above said cross member 10 in order to hide it . In this way, an occupant of the vehicle 1 cannot see this rear central cross member 10. The trim plate 31 is to be considered as being a steel floor sheet. This sheet greatly contributes to the overall performance of the cross member 10 because it directly participates in the holding of the rear seats and its stiffness. This floor sheet forms what is called a hollow body with the cross member 10, and it is this hollow body that improves all of the stiffness, endurance, shock or even vibration performance.

Referring to Figures 5 and 6, the rear central cross member 10 of a vehicle 1 according to the invention is in three distinct parts, comprising a rectilinear segment 15 and two boxes 16, 17. The rectilinear segment 15 is elongated, and the two housings 16, 17 are fixed to the two ends of said rectilinear segment 15, considered along a longitudinal axis thereof. The two housings 16, 17 and the rectilinear segment 15 are preferably made of metal, and advantageously of the same metal. The two housings 16, 17 are secured to the rectilinear segment 15 at the by means of a fixing technique to be chosen from welding and screwing carried out with screws and nuts. The cross member 10 therefore consists of a central rectilinear segment 15 and two side housings 16, 17 fixed to the ends of said central segment 15.

Referring to Figures 5, 6 and 8, the rectilinear segment 15 is formed by an elongated wall of small thickness, the cross section of which is profiled so as to give this segment 15 good rigidity and to allow said segment 15 to s' adapt to the environment of the vehicle 1 in which it will be mounted. This rigidity can for example be achieved by means of at least one rib extending along the central segment 15.

Referring to Figures 5, 6 and 8, the two housings 16, 17 have the same dimensions and are symmetrical to each other. In other words, each case 16, 17 corresponds to the image of the other case 16, 17 that a mirror would reflect.

Referring to Figure 8, each housing 16, 17 is delimited by an open wall delimiting an internal space. Schematically, this wall comprises a first section 18 intended to be attached to a side member 2, 3, and a second section 19 intended to be attached to the central segment 15 of the cross member 10, said two sections 18, 19 being perpendicular. The second section 19 has at least one rib 20, and preferably three parallel ribs 20, extending parallel to a longitudinal axis of the central rectilinear segment 15, so as to reinforce its rigidity. When the housing 16, 17 is fixed to the central rectilinear segment 15, it surrounds the wall materializing said segment 15.

The first section 18 comprises an upper face 21 having first fixing means in the form of a welded nut 22, and intended to cooperate with first complementary fixing means of the electric battery 6 in order to fix said electric battery 6 in the vehicle. This upper face 21 also comprises second fixing means in the form of a welded nut 23 with a piloting function, and intended to cooperate with second complementary fixing means of the rear axle 9 in order to fix said rear axle 9 in the vehicle. 1. This upper face 21 also has a pre-positioning pin 24 intended to correctly position the battery 6 in its compartment 11. FIG. 7 shows the fixing points of the battery 122 and of the rear axle 123 of a vehicle 100 according to the state of the art, and which have been offset on the upper face 21 of a housing 16, 17 of a cross 10 of a vehicle 1 according to the invention. This figure also shows the pin 124 for pre-positioning the electric battery 6 in a vehicle 100 according to the state of the art, and which has also been offset on said upper face 21.

The cross member 10 of a vehicle according to the invention 1, whether at the level of the lateral boxes 16, 17 or of the central rectilinear segment 15, is dimensioned to serve as an attachment point for any element or equipment located in the environment. immediate of said cross 10.

Referring to Figure 1, each side box 16, 17 is fixed both to a spar 2, 3 and to the central rectilinear segment 15 of the cross member 10, so that the first section 18 is in the continuity of the spar 2 , 3 and that the second section 18 is in the continuity of said rectilinear segment 15. In this way, the cross member 10 creates neither an offset with the side members 2, 3, nor a cantilever therewith. Each side box 16, 17 creates a surface contact with the side member 2,

3 to which it is attached, and a surface contact with the central segment 15. In this way, the rear central cross member 10 is firmly anchored in the vehicle 1.

The rear central cross member 10 of a vehicle 1 according to the invention has a certain robustness to contain the effects produced during an impact of said vehicle 1 against an external obstacle, and also serves as an attachment point for certain elements present in it. the vehicle 1, such as for example the electric battery 6 and the rear axle 9.

Figure 9 underlines the importance of properly dimensioning the rear central cross member 10 in particular so that it can effectively contain the effects produced during a side impact of the vehicle 1 against a post 32 (the post is not directly visible on the figure, but its location is suggested). The body of the vehicle 1 deforms laterally, and the cross member 10 must have a certain rigidity to preserve the integrity of the electric battery 6, and more generally, of all the elements revolving around said cross member 10, including the tank 8 to fuel and rear axle 9.

Claims

[Claim 1] Electric vehicle (1, 100) comprising a rear floor delimited by two parallel longitudinal members (2, 3), said rear floor comprising a rear part (4) having a front zone (5) intended for fixing rear seats and housing an electric battery (6), and a rear area (7) intended to support a fuel tank (8), said two areas (5, 7) being separated from each other by a cross member rear central cross member (10) extending in a transverse direction Y of the vehicle (1, 100), characterized in that the rear central cross member (10) is made up of three distinct elements (15, 16, 17), including a central segment (15) rectilinear and two side boxes (16, 17), and in that the central segment (15) extends in a transverse direction Y of the vehicle, each of the two side boxes (16, 17) being secured at one end of said central segment (15) and to a spar. (2, 3).

[Claim 2] Vehicle according to claim 1, characterized in that the two side boxes (16, 17) are symmetrical.

[Claim 3] Vehicle according to any one of claims 1 or 2, characterized in that the central segment (15) and the two boxes (16, 17) are metallic.

[Claim 4] Vehicle according to any one of claims 1 to 3, characterized in that the two side boxes (16, 17) are fixed to the central segment (15) by means of a fixing technique to be chosen from among welding. and screwing carried out with screws and nuts.

[Claim 5] Vehicle according to any one of claims 1 to 4, characterized in that each box (16, 17) once it has been fixed in said vehicle comprises an upper face (21) having fixing means (22, 23) making it possible to fix at least one functional element (6, 9) of said vehicle.

[Claim 6] Vehicle according to claim 5, characterized in that each side box (16, 17) comprises first fixing means (22) cooperating with first complementary fixing means of the electric battery (6) to fix said battery (6) in the vehicle (1).

[Claim 7] Vehicle according to any one of claims 5 or 6, characterized in that each side box (16, 17) comprises second fixing means (23) cooperating with second complementary fixing means of a rear axle (9) for fixing said rear axle (9) in the vehicle (1).

[Claim 8] Vehicle according to any one of claims 1 to 7, characterized in that each side box (16, 17) comprises a pin (24) for pre-positioning the electric battery (6) in the vehicle (1 ).

[Claim 9] Vehicle according to any one of claims 1 to 7, characterized in that each housing (16, 17) comprises at least one stiffening rib (20) extending parallel to the central segment (15).

[Claim 10] Vehicle according to any one of claims 1 to 9, characterized in that each side casing (16, 17) has a first wall (19) forming part of the continuity of the central segment (15) and a second wall (18) forming part of the continuity of the spar (2, 3) to which it is fixed.