Motor vehicle with reinforced rear structure

Abstract

The invention relates to a motor vehicle comprising a rear structure (1), with a rear frame comprising two vertical uprights (3) and a lower edge, said rear structure (1) comprising a rear cross member (5) fixed at said lower edge. The vehicle is remarkable in that the rear cross member (5) comprises a stamped area forming a hollow body comprising a bottom wall (7) and a side wall (37), the hollow body is of elongated shape and has a central portion (9) and two lateral portions (11), each of the lateral portions (11) covering at least a portion of the rear face of the vertical uprights (3), and in that the side wall (37) has at the central portion (9) a width greater than its width at each of said lateral portions (11). The invention also relates to a rear cross member (5). Figure to be published with the abstract: Fig. 1

Description

Title of the invention: Motor vehicle with reinforced rear structure

[0001] The present invention relates to a motor vehicle with a reinforced rear structure to withstand a rear impact. The invention also relates to a cross member for a rear structure of a motor vehicle.

[0002] Document US2020 / 0290676 describes a rear structure of a motor vehicle having a reinforcing element at the rear placed between the rear foot of the rear structure and the rear wheel arch. To this end, the rear foot has a greater thickness at the location where the reinforcing element is affixed. This makes it possible to eliminate torsional deformation at the rear foot.

[0003] However, during a side impact at the rear of the vehicle, the force is distributed along the entire rear structure and not only at the rear pillar, which can cause damage to the entire rear part of the vehicle. Also, during an impact at the rear of the vehicle, it is not obvious that the reinforcement proposed on the rear pillar can allow the entire rear structure to withstand the forces brought into play during said impact.

[0004] The invention aims to improve the previous situation. In particular, the invention seeks to reinforce a rear structure of a motor vehicle, so that the rear structure of said vehicle is preserved in the event of an impact suffered at the rear of the motor vehicle.

[0005] For this purpose, and according to a first aspect, the invention relates to a motor vehicle comprising a rear structure, said rear structure comprising a rear frame for an opening panel, said rear frame comprising two vertical uprights and at least one lower edge arranged between said two vertical uprights, said rear structure comprising a rear crossmember fixed at said lower edge, said vehicle being remarkable in that said rear crossmember comprises a stamped area forming a hollow body comprising a bottom wall and a side wall, the hollow body is of elongated shape and shows a central part and two lateral parts, each of the lateral parts covering at least a part of the rear face of the vertical uprights, and in that the side wall shows at the central part a width greater than its width at each of said lateral parts.

[0006] As will be understood from reading the definition which has just been given, the invention proposes a rear structure of a motor vehicle which makes it possible to absorb the force generated during an impact suffered at the rear of the vehicle. The rear structure of the The motor vehicle according to the invention thus has a cross member which in its central part has a greater thickness compared to the lateral parts. It is understood that when the thickness is greater, in the event of a rear impact, the rear cross member has more capacity to absorb the impact before completely deforming, which makes it possible to preserve, within the limits of the violence of the rear impact, the integrity of the rear structure.

[0007] Preferably, the width of the side wall at the central portion is at least 1.5 times greater than its width at each of said side portions, more preferably at least 1.7 times greater, even more preferably at least 2.0 times greater or at least 2.1 times greater.

[0008] Advantageously, the side wall shows at least one stiffening relief at the level of said central part and / or at the level of each of the lateral parts. For example, said at least one stiffening relief is selected from at least one rib or at least one groove.

[0009] Advantageously, said central part and / or each of the lateral parts are respectively fixed to the lower edge and / or to the rear face of the vertical uprights by means of welding points. For example, the welding points are electric welding points.

[0010] According to a first embodiment, the rear cross member has a rebate, said rebate comprising a central portion extending from the side wall towards the ground. Preferably, said central portion has at least one stiffness zone comprising at least one stiffening relief, said at least one stiffness zone extending both at least in part on the side wall and at least in part on the central portion of the rebate.

[0011] According to a second embodiment, alternative or complementary to the first embodiment, the rear structure comprises a rear leg and the rear crosspiece has a rebate, said rebate comprising a lateral portion extending from the side wall to at least the rear face of the rear leg. Preferably, each of the lateral portions of the rebate has at least one stiffness zone comprising at least one stiffening relief, said at least one stiffness zone extending both at least in part on the side wall and at least in part on the lateral portion of the rebate.

[0012] Advantageously, the lateral portion of the rebate shows at its end opposite said side wall a folded edge oriented towards the front of the vehicle.

[0013] For example, the rear structure further comprises a rear floor and the rear pillar comprises a rear pillar liner, said vehicle is remarkable in that said rear pillar liner comprises at least two fixing lugs, a first lug being fixed to the rear floor, and a second fixing lug being fixed to said lateral portion of the rebate. Preferably, the lateral portion of the rebate is in a plane perpendicular to the first fixing lug.

[0014] For example, said rear floor comprises at least one opening, and the first fixing lug is fixed to the rear floor contiguously at the edge of said opening. Preferably, the first fixing lug is fixed to the rear floor contiguously at the edge of said opening by means of welding points, for example by means of electric welding points.

[0015] According to a second aspect, the invention relates to a crossmember for a rear structure of a motor vehicle as defined according to the first aspect, said crossmember is remarkable in that it comprises a stamped zone forming a hollow body composed of a bottom wall and a side wall, the hollow body being of elongated shape and showing a central part and two lateral parts, the side wall showing at the central part a width greater than its width at each of said lateral parts.

[0016] According to a third aspect, the invention relates to a method for manufacturing a motor vehicle as defined according to the first aspect, in which said vehicle comprises a rear structure, said rear structure comprising a rear frame for an opening panel, said rear frame comprising two vertical uprights and at least one lower edge arranged between said two vertical uprights, said method comprising at least one step of fixing a rear cross member at said lower edge, the method is remarkable in that it further comprises a prior step of forming a rear cross member by stamping. Preferably, said step of fixing a rear cross member at said lower edge is carried out by welding and / or the rear cross member is a cross member as defined according to the second aspect.

[0017] The invention will be well understood and other aspects and advantages will appear clearly on reading the following description given with reference to the attached drawings in which:

[0018] [fig. 1] [fig.l] is a rear view of the rear structure of the motor vehicle according to the invention.

[0019] [fig.2] [fig.2] shows a side view of the rear structure of the vehicle at automobile according to the invention.

[0020] [fig.3] [fig.3] shows a view from below of the rear structure of the vehicle at automobile according to the invention.

[0021] In the remainder of the description, the term "comprise" is synonymous with "include" and is not limiting in that it allows the presence of other elements in the vehicle, the crossmember or the method to which it refers. It is understood that the term "comprise" includes the terms "consist of".

[0022] Similarly, the terms "lower", "upper", "high" and "lower" will be understood according to their usual definition, in which the terms "lower" and "lower" indicate a greater proximity to the ground in the vertical direction than the terms "upper" and "high" respectively.

[0023] The terms “interior” and “exterior” shall be understood to refer to the passenger compartment of the vehicle.

[0024] The terms “longitudinal”, “transverse”, “front” and “rear” will be understood in relation to the general orientation of the vehicle as taken in its normal direction of travel.

[0025] In the various figures, the same references designate identical or similar elements.

[0026] In the event of a rear impact, it is important to control how the forces are absorbed by the rear structure. This helps to maintain the integrity of the rear structure of a motor vehicle in the event of a rear impact.

[0027] To this end, the invention provides a motor vehicle comprising a rear structure 1 as shown in [fig.l]. The rear structure 1 comprises a rear frame for an opening panel, generally for opening the trunk. The rear frame comprises two vertical uprights 3 and at least one lower edge arranged between said two vertical uprights 3. The rear structure 1 comprises a rear crossmember 5 fixed at said lower edge. For example, the rear crossmember 5 is welded at said lower edge, advantageously by means of electric welding spots.

[0028] The vehicle according to the invention is remarkable in that the rear cross member 5 comprises a stamped zone forming a hollow body comprising a bottom wall 7 and a side wall 37, the hollow body being of elongated shape and showing a central part 9 and two lateral parts 11, each of the lateral parts 11 covering at least a part of the rear face of the vertical uprights 3, and in that the side wall 37 shows at the central part 9 a width greater than its width at each of said lateral parts 11.

[0029] For example, said central part 9 is fixed to the lower edge of the rear frame for opening panel by means of welding points and / or each of the side parts 11 is fixed to the rear face of the vertical uprights by means of welding points. For example, the welding points are electric welding points.

[0030] Advantageously, the width of the side wall 37 at the central portion 9 is at least 1.5 times greater than its width at each of said lateral portions 11, preferably at least 1.6 times greater, more preferably at least 1.7 times greater, even more preferably at least 1.8 times greater, or at least 1.9 times greater, or at least 2.0 times greater, or at least 2.1 times greater, or at least 2.2 times greater. For example, the width of the wall on the side 37 is at the level of the central part is 2.0 times greater than its width at the level of each of said lateral parts 11.

[0031] For example, the central part 9 of the hollow body of the rear crosspiece 5 extends between the two inner faces of the vertical uprights 3 forming the rear frame for the opening panel.

[0032] For example, the lateral parts 11 of the hollow body of the rear crosspiece 5 each extend from the inner face of one of the vertical uprights 3 of the rear frame for the opening panel to at least the outer face of said vertical upright 3.

[0033] The fact that the width of the side wall 37 is at the level of the central part 9 greater than its width measured this time at the level of each of the lateral parts 11 makes the hollow body more capable of absorbing a sudden shock at the rear of the vehicle.

[0034] In order to increase the rigidity of the rear crossmember 5, and thus increase the resistance of said crossmember to rear impact, it is preferable for the side wall 37 to have at least one stiffening relief (17; 19) at the central portion 9 of the hollow body and / or on each of the lateral portions 11 of the hollow body. Advantageously, both the central portion 9 and the lateral portions 11 of the hollow body comprise at least one stiffening relief (17; 19).

[0035] For example, said at least one stiffening relief (17; 19) is selected from at least one rib or at least one groove.

[0036] According to a first embodiment, the rear crosspiece 5 has a rebate with a central portion 21 extending from the side wall 37 towards the ground. Preferably, said central portion 9 has at least one stiffness zone 13 comprising at least one stiffening relief 17, said at least one stiffness zone 13 extending both at least in part on the side wall 37 and at least in part on the central portion 21 of the rebate.

[0037] This arrangement also allows the motor vehicle according to the invention to absorb the shock at the rear in a more optimal manner, the central portion 21 of the rebate making it possible to distribute at least part of the force.

[0038] According to a second embodiment, alternative or complementary to the first embodiment, the rear structure 1 comprises a rear leg and the rear crosspiece 5 has a rebate with a lateral portion 23 extending from the side wall 37 to at least the rear face of the rear leg. The lateral portion 23 of the rebate can also advantageously cover the entire rear face of the rear leg.

[0039] This arrangement is advantageous because it allows, in the event of a side impact at the rear, to transmit the force experienced by the side of the vehicle to the central part 9 of the hollow body which has a greater thickness than the lateral part 11. Thus, the rear foot of the rear structure 1 of the vehicle is prevented from undergoing the entire force, which makes it possible to preserve, within the limits of the violence of the impact, the integrity of the rear structure 1 and to limit any damage to the rear cross member 5 only. This arrangement therefore makes it possible to ensure that the rear structure 1 of the motor vehicle is more resistant in the event of a rear impact, whether the impact is sustained on one of the rear sides of the vehicle or rather on the rear center.

[0040] Preferably, each of the lateral portions 23 of the rebate shows at least one stiffness zone 15 comprising at least one stiffening relief 19, said at least one stiffness zone 15 extending both at least in part on the side wall 37 and at least in part on the lateral portion 23 of the rebate.

[0041] This arrangement also allows the motor vehicle according to the invention to absorb the shock at the rear in a more optimal manner. Indeed, the stiffening relief(s) 19 being oriented in the direction of deformation, the transmission of the force is guided in a more optimal manner towards the central part of the hollow body.

[0042] It is also advantageous for the lateral portion 23 of the rebate to have at its end opposite the side wall 37 a folded edge 25 oriented towards the front of the vehicle. [fig.2] is a side view of the rear structure 1 of the motor vehicle. Thus, during a side impact at the rear of the vehicle, the folded edge 25 participates in guiding the forces inwards and therefore towards the central part 9 of the hollow body.

[0043] [Fig. 3] shows that the rear leg of the rear structure can also be reinforced by means of a rear leg lining 29 which comprises at least two fixing lugs. A first fixing lug 31 is fixed to the rear floor 27 of the rear structure 1, preferably by welding, more preferably by means of electric welding points. A second fixing lug 33 is fixed to the lateral portion 23 of the rebate.

[0044] Preferably, the lateral portion 23 of the rebate is in a plane perpendicular to the first fixing lug 31.

[0045] Advantageously, the first fixing lug 31 is fixed to the rear floor 27 near an opening 35 present on the rear floor 27. The opening 35 is useful for leaving space for the welding tools in order to fix together the lateral portion 23 of the rebate to the rear pillar lining 29 and also the rear pillar lining 29 to the rear floor 27 via the first fixing lug 31. The opening 35 can then have other uses, such as for example facilitating the passage of any electrical cables necessary for the vehicle.

[0046] The invention also relates to a crossmember for a rear structure 1 of a motor vehicle as described above, said crossmember 5 is remarkable in that it comprises a stamped zone forming a hollow body composed of a bottom wall 7 and a side wall 37. Said bottom wall 7 is arranged to be fixed, preferably by welding, in particular by means of electric welding points, to a lower edge of a rear frame for an opening panel of a rear structure 1 of a motor vehicle. Said lower edge of said rear frame is arranged between two vertical uprights 3.

[0047] The hollow body of the stamped area of ​​the crosspiece 5 is of elongated shape and shows a central part 9 and two lateral parts 11 and the side wall 37 shows at the central part (9) a width greater than its width at each of said lateral parts.

[0048] The two side parts 11 are arranged to be fixed, preferably by welding, in particular by means of electric welding points, to said vertical uprights 3 of said rear frame for opening panel.

[0049] The invention also relates to a method of manufacturing a motor vehicle as described above, in which said vehicle comprises a rear structure 1, said rear structure 1 comprising a rear frame for an opening panel, said rear frame comprising two vertical uprights 3 and at least one lower edge arranged between said two vertical uprights 3, said method comprising at least one step of fixing a rear crossmember 5 at said lower edge. The method is remarkable in that it further comprises a prior step of forming a rear crossmember 5 by stamping.

[0050] Preferably, said step of fixing a rear cross member 5 at said lower edge is carried out by welding, for example by means of electric welding spots.

[0051] Preferably, the rear cross member 5 is a cross member as described above.

Claims

Claims

1. A motor vehicle comprising a rear structure (1), said rear structure (1) comprising a rear frame for an opening panel, said rear frame comprising two vertical uprights (3) and at least one lower edge disposed between said two vertical uprights (3), said rear structure (1) comprising a rear cross member (5) fixed at said lower edge, said vehicle being characterized in that said rear cross member (5) comprises a stamped area forming a hollow body comprising a bottom wall (7) and a side wall (37), the hollow body is of elongated shape and has a central portion (9) and two lateral portions (11), each of the lateral portions (11) covering at least a portion of the rear face of the vertical uprights (3), and in that the side wall (37) has at the central portion (9) a width greater than its width at each of said lateral portions (11).

2. Vehicle according to claim 1, characterized in that the width of the side wall (37) at the central part (9) is at least 1.5 times greater than its width at each of said side parts (11).

3. Vehicle according to claim 1 or 2, characterized in that the side wall (37) shows at least one stiffening relief (17; 19) at the level of said central part (9) and / or at the level of each of the lateral parts (11).

4. Vehicle according to one of claims 1 to 3, characterized in that said central part (9) and / or each of the lateral parts (11) are respectively fixed to the lower edge and / or to the rear face of the vertical uprights (3) by means of welding points.

5. Vehicle according to one of claims 1 to 4, characterized in that the rear cross member (5) has a rebate, said rebate comprising a central portion (21) extending from the side wall (37) towards the ground; preferably, said central portion (9) has at least one stiffness zone (13) comprising at least one stiffening relief (17), said at least one stiffness zone (13) extending both at least partly on the side wall (37) and at least partly on the central portion (21) of the rebate.

6. Vehicle according to one of claims 1 to 5, characterized in that the rear structure (1) comprises a rear foot and in that the cross member rear (5) shows a rebate, said rebate comprising a lateral portion (23) extending from the side wall (37) to at least the rear face of the rear foot; preferably, each of the lateral portions (23) of the rebate shows at least one stiffness zone (15) comprising at least one stiffening relief (19), said at least one stiffness zone (15) extending both at least partly on the side wall (37) and at least partly on the lateral portion (23) of the rebate.

7. Vehicle according to claim 6, characterized in that the lateral portion (23) of the rebate shows at its end opposite said side wall (37) a folded edge (25) oriented towards the front of the vehicle.

8. Vehicle according to claim 6 or 7, the rear structure (1) further comprising a rear floor (27) and the rear leg comprises a rear leg lining (29), said vehicle being characterized in that said rear leg lining (29) comprises at least two fixing lugs, a first lug (31) being fixed on the rear floor (27), and a second fixing lug (33) being fixed to said lateral portion (23) of the rebate; preferably, the lateral portion (23) of the rebate is in a plane perpendicular to the first fixing lug (31).

9. Vehicle according to claim 8, characterized in that said rear floor (27) comprises at least one opening (35), and in that the first fixing lug (31) is fixed to the rear floor (27) contiguously to the edge of said opening (35); preferably, by means of welding points.

10. Cross member (5) for a rear structure of a motor vehicle as defined according to one of claims 1 to 9, said cross member (5) is characterized in that it comprises a stamped zone forming a hollow body composed of a bottom wall (7) and a side wall (37), the hollow body being of elongated shape and showing a central part (9) and two lateral parts (11), the side wall (37) showing at the central part (9) a width greater than its width at each of said lateral parts (11).

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