FR3127921A1 - Motor vehicle with a rear structure comprising a reinforcing piece. - Google Patents

Abstract

Motor vehicle (10) with a rear structure which comprises two side rails (20); at least one battery support beam (24) fixed to the two longerons (20); and a battery pack (26) for a vehicle traction battery, attached to the front of the battery support beam (24). The rear structure further includes a rear panel (14) that includes a frame forming an opening for a tailgate, the frame including a bottom edge (16) to which a tailgate latch (18) is attached. The vehicle comprises at least one reinforcing piece (28) fixed to the rear structure of the vehicle, extending between the rear panel and the battery support crossmember (24), and arranged at a distance of less than 20 cm from the locking element (18) in the transverse direction of the vehicle. Figure to be published with abstract: Fig. 1

Description

Motor vehicle with a rear structure comprising a reinforcing piece.

The present invention relates to the field of motor vehicles comprising a rear structure, and in particular a rear structure comprising devices for protection against rear impacts.

Motor vehicles must satisfy many services, in particular in terms of protection against shocks.

Tests measure the resistance of vehicles during a rear impact. During these tests, a moving trolley is sent at a given speed of 50 to 80 km/h against the rear bumper of a stationary vehicle. The trolley is configured to reproduce the effect of a barrier hitting the vehicle at the height of the bumper.

The rear structure of a motor vehicle generally comprises a boot delimited by a rear panel, a bumper device with at least one bumper beam, two side rails to which the bumper beam is fixed, and a floor rear arranged between the longitudinal members.

In the context of an electric vehicle or an electric hybrid vehicle, the rear of the vehicle may further comprise a traction battery pack of the vehicle. The battery block is substantially parallelepipedic in shape and often placed under the rear floor, i.e. at boot level. The rear floor may include a raised central part to accommodate the battery pack and reduce its protrusion below the vehicle.

During a rear impact, the components of the rear bumper system are configured in such a way as to transmit the forces received to the side members. The elements located above the rear bumper are designed to deform by absorbing the shock.

The presence of a traction battery pack in an electric motor vehicle is an additional constraint in the event of a rear impact. Indeed, the deformation of the structure, in particular at the level of the rear panel, is likely to cause an intrusion into the battery pack. There is then a risk of electrocution or chemical burns for the passengers.

Motor vehicle rear structure solutions are known, such as for example in the document JP2014189248 which describes a trunk compartment of a motor vehicle. The trunk compartment comprises a lower floor and an upper floor with a spare wheel housing. The lower floor comprises a longitudinal reinforcement element which extends between the rear seats of the vehicle and the rear panel delimiting the rear of the vehicle trunk. The longitudinal reinforcement element comprises one end which serves as an anchorage for the rear seat, and another end to which a towing eye is attached. The rear reinforcement makes it possible to stiffen the rear structure of the vehicle.

This solution can reinforce the structure during a rear impact, but is not suitable if the vehicle is fitted with a traction battery housed in the floor of the boot.

The aim of the invention is to improve the state of the art. The aim of the invention is in particular to propose a motor vehicle comprising a rear structure in which a traction battery is arranged and which limits the risks of intrusion into the battery pack during a rear impact.

To this end and according to a first aspect, the subject of the invention is a motor vehicle with a rear structure which comprises two side rails; at least one battery support cross member fixed to the two longerons; and a battery pack for a vehicle traction battery, attached to the front of the battery carrier crossmember.

The rear structure further includes a rear panel that includes a frame forming an opening for a tailgate, the frame including a bottom edge to which a hatch latch is attached.

The vehicle is remarkable in that it comprises at least one reinforcing piece fixed to the rear structure of the vehicle, extending between the rear panel and the battery support crossmember, and arranged at a distance of less than 20 cm from the locking element in the transverse direction of the vehicle; preferably within 10 cm of the locking element.

It was noted that during a rear impact test, the upper part of the carriage which hits the vehicle pushes the elements of the rear panel forward of the bumper beam. These components enter the boot with a rotational movement around the bumper beam, and are likely to come into contact with the traction battery which is located under the floor. The locking element may include a thick steel striker likely to cause serious damage if it intrudes on the traction battery. The reinforcement part arranged near or in the extension of the locking element of the tailgate of the boot acts as a spacer, it makes it possible to limit the movement of the locking element in the event of a rear impact and to limit the risk of intrusion into the battery pack.

In embodiments, the rear structure further comprises a floor, the vehicle is remarkable in that the reinforcing part is fixed on the one hand to the boot floor, and on the other hand to the rear panel.

Fixing the reinforcement piece to these two elements makes it possible to maintain the arrangement of the reinforcement piece during a rear impact.

In embodiments, the rear structure further comprises a floor, the vehicle is notable in that the reinforcing part comprises at least one angled element, with at least one horizontal arm arranged above the floor, and at least a vertical arm attached to the rear panel.

A right-angled part is a very simple part to make which can be easily mounted on an existing electric or electric hybrid type motor vehicle.

Preferably, the reinforcing piece further comprises at least one oblique arm joining the ends of the horizontal arm and of the vertical arm.

The oblique arm provides more rigidity to the reinforcement part which can be made of plastic, composite or metallic materials. The reinforcing piece then has a substantially triangular shape.

Preferably, the reinforcement piece comprises a flange fixed to the floor, and extending between the battery support crosspiece and the rear panel; the horizontal arm of the angle element is fixed to the footing.

The reinforcement piece thus produced is higher than the battery support crosspiece. In the event of an impact, the reinforcement piece limits intrusion of the rear panel above the battery support crossmember.

Advantageously, the oblique arm has a width, in the transverse direction of the vehicle, less than the width of the horizontal and vertical arms of the reinforcement piece.

An oblique arm of width less than the width of the horizontal and vertical arms makes it possible to reduce the mass of the reinforcement part without reducing its rigidity.

Preferably, the reinforcing piece has a width in the transverse direction of the vehicle of at least 5.5 cm; preferably at least 7 cm; preferably at least 10 cm.

The reinforcement piece is thus dimensioned so as to limit the movement of the locking element

Preferably, the reinforcing piece comprises one or more notches, slots, undulations, or stiffening ribs.

In embodiments, the vehicle further comprises a floor, and a floor lining arranged above the floor, the vehicle is remarkable in that the reinforcing piece is arranged below the floor lining.

The reinforcement piece is thus not visible to a user from the trunk of the vehicle.

Preferably, the reinforcing piece is fixed to the rear structure of the vehicle by gluing, by screwing, or by rivets. The fastening means can be sealed, in particular at the level of the vehicle floor.

In some embodiments, the vehicle comprises at least two reinforcing pieces arranged on either side of the locking element in the transverse direction of the vehicle.

In some embodiments, the locking element is a trunk striker and in that the reinforcing piece is arranged in alignment with the locking element in the longitudinal direction of the vehicle.

The invention will be well understood and other aspects and advantages will appear clearly on reading the following description, given by way of example with reference to the attached drawing plates on which:

there is a side view of a motor vehicle according to one embodiment of the invention, showing the rear structure;

there is a perspective view of a detail of the rear structure of a motor vehicle according to one embodiment of the invention;

there is a perspective view of an isolated reinforcing piece of the ;

there is a perspective view of a detail of the rear structure of a motor vehicle according to another embodiment of the invention;

there is a perspective view of an isolated reinforcing piece of the .

In the rest of the description, the term “understand” is synonymous with “include” and is not limiting in that it authorizes the presence of other elements in the vehicle to which it refers. It is understood that the term “include” includes the terms “consist of”.

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

The terms "longitudinal", "transverse", "front", "front", "rear", "behind" shall be understood in relation to the general orientation of the vehicle as taken in its normal direction of travel.

A motor vehicle 10 comprises a rear structure shown in . Figures 1 to 4 show one side of the rear structure, the skilled person can easily deduce the characteristics of the other side by symmetry with respect to a median longitudinal plane of the vehicle.

The rear structure is located behind the passenger compartment of the vehicle and may include the trunk compartment 12. The vehicle may be a hatchback type vehicle as shown in , notchback, or other.

The trunk 12 is delimited at the rear by a rear panel 14 which comprises a frame forming an opening for a tailgate, not shown. The back panel frame 14 includes vertical borders, a top border, and a bottom border 16.

The tailgate can be opened and closed by pivoting around hinges, not shown, preferably mounted on the top edge of the rear panel frame. In the closed position, the tailgate is engaged in the rear panel opening.

A locking element 18 of the tailgate is fixed to the lower edge 16. The locking element can be a striker, a trunk lock, or any other element. In the examples shown in Figures 1, 2 and 4, the locking element 18 is a latch intended to engage in a lock fixed to the tailgate.

The rear structure comprises two side rails 20, one of which is shown in Figures 1, 2 and 4. The rails 20 can be linked to a rear bumper beam, not shown. In the event of a rear impact, the impact energy is transmitted to the side members.

The rear structure further comprises a floor 22, which extends between the two side members 20. The floor 22 is preferably arranged below the side members 20, and can be fixed to the latter or to another element of the structure of the vehicle. The floor 22 can serve as a support for vehicle equipment such as for example the speakers of the audio system of the vehicle.

At least one battery support beam 24 is arranged in the transverse direction of the vehicle. The support beam 24 can be fixed to the two longerons 20 above the floor 22 of the rear structure. The support crosspiece 24 is preferably a metal profile.

A battery pack 26 for a traction battery of the vehicle is attached to the front of the battery support beam 24. The battery pack 26 can be fixed to the support crosspiece 24, for example, by screwing or by any other means, and preferably in a removable manner. The floor 22 may then include an area raised upwards which forms a housing for the battery pack 26.

The motor vehicle 10 further comprises at least one reinforcing piece 28 fixed to the rear structure of the vehicle. The reinforcement piece 28 is an elongated piece which extends between the rear panel 14 and the battery support beam 24. The reinforcing piece 28 can extend over at least 50% of the distance between the rear panel 14 and the battery support crosspiece 24; preferably at least 80% of the distance between the rear panel 14 and the battery support beam 24; preferably over the entire distance between the rear panel 14 and the battery support crosspiece 24. The reinforcing piece 28 preferably extends in a longitudinal direction of the motor vehicle 10, i.e. perpendicular to the battery support crosspiece 24.

According to variants, not shown, the vehicle comprises a plurality of reinforcement parts distributed over the length of the battery support crosspiece. The reinforcing pieces can be arranged on either side of the locking element in the transverse direction of the vehicle. Preferably, the reinforcing pieces are arranged symmetrically on either side of the locking element in the transverse direction of the vehicle.

In the event of a rear impact, the reinforcing piece 28 rests both on the battery support crosspiece 24 and on the rear panel 14 so as to form a spacer between these two elements. It thus makes it possible to limit the movement of the rear panel 14 forwards, and to prevent an element of the rear panel from being introduced into the battery pack during an impact.

The reinforcing part 28 can be fixed to one or more element of the rear structure of the motor vehicle 10. For example, the reinforcing part can be fixed to the battery support crosspiece 24, to the floor 22 or to the rear panel 14. reinforcement piece 28 can be fixed to the rear structure of the vehicle by gluing, by screwing, or by rivets.

As shown in Figures 1, 2 and 4, below the lower edge 16, the frame comprises a substantially vertical inner surface 30 which extends inside the trunk 12 to the floor 22. The reinforcing piece 28 is here fixed on the one hand to the floor 22, and on the other hand to the inner surface 30 of the rear panel.

The reinforcing piece 28 is arranged at a distance of less than 20 cm from the locking element 18 in the transverse direction of the vehicle, preferably at less than 10 cm from the locking element 18. In the following examples shown in Figures 2 to 5, the reinforcing piece 28 is arranged in alignment with the locking element 18 in the longitudinal direction of the vehicle.

For example, as shown in Figures 2 to 5, the reinforcement piece 28 comprises at least one angled element, with at least one horizontal arm 32 arranged above the floor 22, and at least one vertical arm 34 arranged opposite or against the back panel. The vertical arm 34 then extends upwards from the floor 22. The reinforcement piece 28 may further comprise an oblique arm 36 joining the ends of the vertical arm and the horizontal arm.

The reinforcing piece 28 may include one or more notches, openings, undulations, or stiffening ribs. For example, as shown in Figures 1 to 5, the reinforcement piece 28 includes a stiffening slot 37.

Upright arm 34 may extend upward to the locking member, but is preferably hidden from a user. For example, motor vehicle 10 may include floor trim 38, shown in , which forms the interior floor of the trunk of the vehicle and which is arranged above the floor. The reinforcing piece 28 can then be arranged below the floor lining 38. In this case, the vertical arm 34 of the reinforcing piece 28 can extend from the floor 22 to the floor lining 38.

The reinforcing part 28 can be a part produced by injection molding of plastic material such as, for example, thermoplastic polymer chosen from among polypropylene (PP), expanded polypropylene (EPP), polyethylene (PE), polyphthalamide (PPA), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyamide-imide (PAI), polyetherimide (PEI), polyarylamide (PAA), or polyamide (PA) such as for example polyamide 6 (PA 6 or polycaprolactam) or polyamide 6.6 (PA 6.6 or polyhexamethylene adipamide), or mixtures thereof. The piece obtained is light. The reinforcement part 28 can also be a part made of composite material, or even a metal part.

In order to maintain good rigidity in the event of impact, the reinforcing piece has a width in the transverse direction of the vehicle of at least 5.5 cm; preferably at least 7 cm; preferably at least 10 cm.

In the embodiment shown in Figures 2 and 3, the reinforcing piece 28 comprises a flange 40 fixed to the floor 22, which extends between the battery support crosspiece 24 and the rear panel 14 with a height, preferably, at least equal to that of the battery support crossmember. The reinforcement piece 28 comprises a bracket element with a horizontal arm 32 fixed above the sole 40, and a vertical arm 34 which is fixed to the interior surface 30 of the rear panel 14.

The inner surface 30 of the rear panel 14 may have a stepped profile with, for example, a lower part 42 in front of an upper part 44. In order to follow the profile of the inner surface 30, the sole 40 may have the same height than the lower part 42. As shown in , the square element can then be arranged cantilevered at the rear of the sole 40, and can be fixed to the upper part of the inner surface 30 of the rear panel 14.

In the embodiments of FIGS. 1 to 3, the oblique arm 36 of the angled element has a width, in the transverse direction of the vehicle, equal to the width of the horizontal 32 and vertical 34 arms of the reinforcement piece. According to the variants, the reinforcement part can comprise an oblique arm of smaller width, and the reinforcement part can also comprise a plurality of oblique arms or a plurality of angled elements fixed on the same sole.

In the embodiment shown in Figures 4 and 5, the reinforcing piece 28 comprises a horizontal arm 32 formed by a plate fixed to the floor 22 of the rear structure, and a vertical arm 34 formed by a plate in the extension of the horizontal arm , attached to the inner surface 30 of the rear panel. The two arms 32, 34 can for example be formed by a single folded plate.

The front end of the horizontal arm 32 extends into a vertical fold 46 arranged opposite the battery support crosspiece 24.

Interior surface 30 of rear panel 14 may have a stepped profile. In order to follow the profile of the interior surface 30, the vertical arm 34 may comprise the same stepped profile as the interior surface 30, as shown in .

The reinforcing piece 28 comprises an oblique arm 36 of smaller width, in the transverse direction of the vehicle, equal than the horizontal and vertical arms of the reinforcing piece. For example, the oblique arm comprises a base part 48 fixed to the horizontal arm 32, and to the vertical fold 46, and an oblique part 50 fixed above the base part 48 and to the vertical arm 34. The oblique part joins the end of the vertical fold 46 and the end of the vertical arm 34.

The reinforcement piece 28 can also comprise an oblique arm of greater width, or a plurality of oblique arms 36.

Claims (10)

Motor vehicle (10) with a rear structure which comprises two side rails (20); at least one battery support beam (24) fixed to the two longerons (20); and a battery pack (26) for a vehicle traction battery, attached to the front of the battery support beam (24); the rear structure further comprises a rear panel (14) which comprises a frame forming an opening for a tailgate, the frame comprising a lower edge (16) to which is attached a locking member (18) of the tailgate; the vehicle is characterized in that it comprises at least one reinforcing piece (28) fixed to the rear structure of the vehicle, extending between the rear panel and the battery support crossmember (24), and arranged at a distance less than 20 cm from the locking element (18) in the transverse direction of the vehicle. Motor vehicle (10) according to claim 1, the rear structure further comprising a floor (22), the vehicle is characterized in that the reinforcing piece is fixed on the one hand to the boot floor, and on the other hand to the rear panel (14). Motor vehicle (10) according to any one of claims 1 or 2, the rear structure further comprising a floor (22), the vehicle is characterized in that the reinforcing part (28) comprises at least one angled element, with at least one horizontal arm (32) arranged above the floor (22), and at least one vertical arm (34) fixed to the rear panel (14). Motor vehicle (10) according to Claim 3, characterized in that the reinforcing piece (28) further comprises at least one oblique arm (36) joining the ends of the horizontal arm (32) and of the vertical arm (34). Motor vehicle (10) according to Claim 4, characterized in that the oblique arm (36) has a width, in the transverse direction of the vehicle, less than the width of the horizontal (32) and vertical (34) arms of the reinforcing piece. (28). Motor vehicle (10) according to any one of Claims 3 to 5, characterized in that the reinforcing piece (28) comprises a flange (40) fixed to the floor (22), and extending between the support crosspiece ( 24) battery and rear panel (14); the horizontal arm (32) of the bracket element is fixed to the sole (40). Motor vehicle (10) according to any one of the preceding claims 1 to 6, characterized in that the reinforcing piece (28) has a width in the transverse direction of the vehicle of at least 5.5 cm; preferably at least 10 cm. Motor vehicle (10) according to any one of the preceding claims 1 to 7, further comprising a floor (22), and a floor trim (38) arranged above the floor (22), the vehicle is characterized in that that the reinforcing piece (28) is arranged below the floor trim (38). Motor vehicle (10) according to any one of the preceding claims 1 to 8, characterized in that it comprises at least two reinforcing parts (28) arranged on either side of the locking element (18) in the transverse direction of the vehicle. Motor vehicle (10) according to any one of the preceding claims, 1 to 9, characterized in that the locking element (18) is a boot striker and in that the reinforcing piece (28) is arranged in the alignment of the locking element (18) in the longitudinal direction of the vehicle.