FR3133353A1 - Rear bumper assembly for motor vehicle - Google Patents

Abstract

The invention relates to an interface part (13) intended to be fixed integrally to a crosspiece (11) of a set of bumpers (1), the interface part (13) comprising a device (14) capable of taking the shape of a through hole or a depression (142) intended to be located directly behind a fixing system (212) of an access hatch (211) of a bumper skin (21) covering the crosspiece (11), the access hatch (211) allowing the fixing of a towing eye on its fixing member, relative to a longitudinal axis (X) of the motor vehicle on which the interface part (13) is intended to be mounted. Figure to be published with the abstract: Fig. 2

Description

Rear bumper assembly for motor vehicle

The technical context of the present invention is that of rear bumper accessories for motor vehicles, and in particular that of the interactions between the safety elements and the attachment functionalities of a towing eye. More particularly, the invention relates to a set of rear bumpers for a motor vehicle.

In the state of the art, motor vehicles are known comprising a rear part comprising a rear cross member installed transversely and masked by a bumper skin. This rear crossmember is designed to absorb in a regulatory manner at least partially longitudinal shocks suffered from the rear by the motor vehicle.

We also know the equipment of such a rear crossmember with interface parts located at each of its ends, in order to better respond to so-called “ethical” shocks which occur on one of said interface parts at low speed. relative and in a direction having longitudinal and transverse components. In such ethical shocks, the interface part prevents the bumper from being locally damaged at its lateral end.

However, it was noted that, in a completely inappropriate and unanticipated manner, the presence on the bumper skin of an access hatch to a fixing member of a towing eye of the motor vehicle, fixed integrally to a rear spar, through a shock absorption system of the rear cross member, collided with the interface part during an ethical impact. This unwanted collision leads to plastic deformation or even breakage of the bumper skin which is also not desired.

The object of the present invention is to propose a new set of bumpers in order to respond at least largely to the previous problems and to also lead to other advantages.

Another aim of the invention is to respond satisfactorily to the regulatory expectations of an ethical shock.

Another aim of the invention is to avoid contact between the bumper skin and the interface part during an ethical impact.

According to a first aspect of the invention, at least one of the aforementioned objectives is achieved with a set of rear bumpers for a motor vehicle, the set of bumpers comprising (i) a crosspiece intended to extend transversely relative to the vehicle automobile, (ii) a shock absorption system configured to be able to absorb a rear shock transmitted by the crossmember, the shock absorption system being integral with the crossmember at each of the lateral ends of said crossmember, the system shock absorption being intended to be fixed integrally to a rear spar of the motor vehicle, (iii) interface parts each forming a non-zero angle with a rear face of the crosspiece intended to be placed opposite a skin of bumper of the motor vehicle, the interface parts being integral with the crossmember at its lateral ends. In the set of bumpers according to the invention, at least one of the interface parts comprises, at a part intended to be located opposite an access hatch to a member for fixing a ring of towing, a device configured to allow a longitudinal clearance greater than 8 mm between an access hatch fixing system and said device.

In the context of the invention, the longitudinal direction is taken in a direction which extends between the rear and the front of the motor vehicle, the transverse direction is taken in a direction perpendicular to the longitudinal direction, between a straight edge and a left edge of the motor vehicle, and the vertical direction is taken in a direction simultaneously perpendicular to the longitudinal and transverse directions.

The interface parts are configured to, when they undergo a shock with a transverse component, reduce the probability of contact between the bumper and the lateral end concerned of the crossmember and absorb by deformation at least part of the energy of said shock .

The access hatch is formed on the bumper skin. It is fixed in a movable or removable manner to the bumper skin, via its fixing system.

Thus, in accordance with the invention according to its first aspect, the device is configured to authorize longitudinal movement of the access hatch and/or its fixing system towards the crosspiece and the corresponding interface part, in particular as generated during deformation of the bumper skin resulting from an “ethical shock”, so as to avoid any contact between, on the one hand, said access hatch and/or said fixing system and, On the other hand, the interface part.

According to the invention, the device of at least one of the interface parts allows rearward movement of the bumper skin and the access hatch to the towing eye, including its fastening system. said bumper skin, without said fixing system coming into contact with said interference part. For this purpose, part of the interference piece, if it exists, is located, facing the fixing system and relative to the longitudinal axis, at a distance greater than 8 mm so as to authorize such movement towards the rear of the fixing system.

The set of bumpers conforming to the first aspect of the invention advantageously comprises at least one of the improvements below, the technical characteristics forming these improvements being able to be taken alone or in combination:

- the device is configured to allow a longitudinal clearance greater than 10 mm between an access hatch fixing system and said device. This advantageous configuration allows you to benefit from a safety margin before contact - and possible plastic deformation - of the fixing system of the bumper skin or of the bumper skin itself with the interface part;

- according to a first alternative embodiment, the device takes the form of an opening formed in the at least one interface part, the opening being located opposite the fixing system, relative to a longitudinal axis. This advantageous configuration thus makes it possible to avoid any subsequent contact between the fixing system of the bumper skin access hatch and the interface part. In this first alternative embodiment, the interface part is preferably planar;

- the opening has dimensions and shapes such that it is configured to allow contactless insertion of the fixing system into the opening. Thus, the shape and dimensions of the opening forming the device on the interface part depend on the geometry and the position of the fixing system of the bumper skin access hatch. As a non-limiting example, the opening has a triangular shape;

- according to a second alternative embodiment, the device takes the form of a stamping formed on the at least one interface part, so that the stamping forms a depression located opposite the fixing system, relative to an axis longitudinal, said interface part. In this alternative embodiment, the depression of the interface part is understood in the longitudinal direction: the interface part comprises (i) a standard contact face conforming to that which can be found in the interface parts known and (ii) the depression located closer to the crosspiece relative to the standard contact face. The shape of the interface part is therefore no longer completely flat. Therefore, when the bumper skin is assembled relative to the set of bumpers, a first part of the interface part, forming the standard contact face is located at a first distance from the bumper skin located opposite, and a second part of the interface part is located at a second distance from the bumper skin located opposite, and in particular from its access hatch fixing system;

- the depression formed by the stamping extends along a vertical axis of the at least one interface part. More particularly, the depression forms a plane whose vertical axis forms a generator;

- the device of the interface part is located near a lateral edge of said interface part, on the side of the lateral end of the crosspiece on which said interface part is secured. In particular, the device of the interface part is located near the lateral end of the crosspiece to which the interface part is secured;

- the interface part is formed from a steel sheet whose thickness is between 2 mm and 3 mm, preferably equal to 2.5 mm.

According to a second aspect of the invention, there is proposed an arrangement of bumpers comprising the set of bumpers conforming to the first aspect of the invention or according to any of its improvements and a bumper skin, the fixing system of the bumper skin access hatch being located opposite the device of the bumper assembly.

Advantageously, in the case where the system for fixing the access hatch to the bumper skin is of the type of an opening, then the opening is located opposite the device of the bumper assembly.

According to a second aspect of the invention, there is proposed a motor vehicle comprising an arrangement of bumpers conforming to the second aspect of the invention.

Various embodiments of the invention are planned, integrating according to all of their possible combinations the different optional characteristics exposed here.

Other characteristics and advantages of the invention will appear further through the description which follows on the one hand, and several examples of embodiment given for informational and non-limiting purposes with reference to the appended schematic drawings on the other hand, in which :

illustrates a general view of an arrangement of bumpers for a motor vehicle, in accordance with the invention;

illustrates a perspective and detail view of a bumper arrangement according to the second aspect of the invention;

illustrates a perspective and detail view of a first embodiment of the bumper assembly conforming to the first aspect of the invention;

illustrates a perspective and detail view of a second embodiment of the bumper assembly conforming to the first aspect of the invention.

Of course, the characteristics, variants and different embodiments of the invention can be associated with each other, in various combinations, to the extent that they are not incompatible or exclusive of each other. It will be possible in particular to imagine variants of the invention comprising only a selection of characteristics described subsequently in isolation from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention from to the prior art.

In particular, all the variants and all the embodiments described can be combined with each other if nothing opposes this combination on a technical level.

In the figures, elements common to several figures retain the same reference. In particular, in the exemplary embodiments illustrated in the figures below, the longitudinal direction X is taken in a direction which extends between the rear and the front of the motor vehicle, the transverse direction Y is taken in a direction perpendicular to the longitudinal direction X, between a right edge and a left edge of the motor vehicle, and the vertical direction Z is taken in a direction simultaneously perpendicular to the longitudinal directions

With reference to FIGURES 1 to 4, the invention relates to a set of rear bumpers 1 for a motor vehicle, the set of bumpers 1 comprising:

- a crosspiece 11 intended to extend transversely in relation to the motor vehicle. The crossmember 11 forms a rigid element configured to be able to transmit the forces resulting from an impact at the rear of the motor vehicle, to structural elements of said motor vehicle, such as for example side rails. In the various embodiments illustrated, the crosspiece 11 generally takes the form of a solid or hollow beam, which extends in the transverse direction Y in a rectilinear or, possibly, curved manner;

- a shock absorption system 12 configured to be able to absorb a rear shock transmitted by the crosspiece 11, the shock absorption system 12 being integral with the crosspiece 11 at each of the lateral ends 111 of said crosspiece 11, the shock absorption system 12 being intended to be fixed integrally to a rear spar of the motor vehicle. The shock absorption system establishes a connection between the crossmember 11, taken at each of its ends, and the rear side rails of the motor vehicle. Each absorption system is configured to be able to deform in the longitudinal direction X in order to allow dissipation of the mechanical energy resulting from the shock. For this purpose, the absorption system takes the form of a prismatic accordion beam, formed by a series of folds and/or folding beginnings which extend in the vertical direction Z;

- interface parts 13 each forming a non-zero angle with a rear face of the crosspiece 11 intended to be placed opposite a bumper skin 21 of the motor vehicle, the interface parts 13 being integral with the crosspiece 11 at its lateral ends 111. The interface parts 13 have the function of reducing the probability of direct contact between the bumper skin 21 and the crosspiece 11. To this end, the interface parts 13 form an angle non-zero with the crosspiece 11 so as to be better oriented relative to a part of the bumper skin 21 located near the lateral end 111 of the crosspiece 11. Thus, each interface piece 13 is located longitudinally in a intermediate position between a rear face of the bumper skin 21 and the crosspiece 11.

In the set of bumpers 1 according to the invention, at least one of the interface parts 13 comprises, at the level of a part intended to be located opposite an access hatch 211 to a fixing member of a towing eye, a device 14 configured to allow a longitudinal clearance DL greater than 8 mm between a fixing system 212 of the access hatch 211 and said device 14.

The fixing member of the towing ring takes the form for example of a threaded cylinder which extends through the shock absorption system 12. The towing ring is thus intended to be coupled to its member fixing by screwing. This screwing is made possible by local access provided on the bumper skin 21, just opposite the fixing member, via the access hatch 211.

Additionally, access to the fixing member is made possible, through the interface part 13, by the presence of a light 131 on said interface part 13. The light 131 is, relative to the transverse axis Y and the vertical axis Z, aligned with the fixing member and the access hatch 211 provided on the bumper skin 21.

The access hatch 211 comes from the material with the bumper skin 21, or it is attached to said bumper skin 21. In all cases, the access hatch 211 is linked to the bumper skin 21 by a system fixing device 212 which allows both to secure it, but also to allow its pivoting in order to make access to the fixing member possible.

For this purpose, the fixing system 212 of the access hatch 211 takes the form of a protrusion which extends from the bumper skin 21 towards the interface part 13 located opposite.

In the context of the present invention, the interface part 13 has been modified and adapted so as to guarantee the presence of a longitudinal play DL behind the fixing system 212, in the direction of the crosspiece 11 and relative to the longitudinal axis X, greater than or equal to 8 mm.

For this purpose, the interface part 13 comprises the device 14 in order to authorize a possible longitudinal depression of the bumper skin and/or of the fixing system 212 of the access hatch 211 in the direction of the crosspiece 11, relatively to the longitudinal axis X, without contact between said fixing system 212 and said interface part 13.

Two alternative embodiments are planned in the context of the invention:

- according to a first alternative embodiment illustrated on the , the device 14 takes the form of an opening 141 formed in the at least one interface part 13, the opening 141 being located opposite the fixing system 212, relative to a longitudinal axis X. The opening 141 has dimensions and shapes such that it is configured to allow contactless insertion of the fixing system 212 into the opening 141. In particular, the opening 141 preferably has a triangular shape, one side of which extends in a parallel manner to a side edge of the interface part 13. Advantageously, the opening 141 has the shape of a right triangle, preferably isosceles. Furthermore, relative to a transverse direction Y, the opening 141 is located at a proximal side of the transverse end of the crosspiece 11 with which the interface part 13 is associated;

- according to a second alternative embodiment illustrated on the , the device 14 takes the form of a stamping formed on the at least one interface part 13, so that the stamping forms a depression 142 located opposite the fixing system 212, relative to a longitudinal axis X, said interface part 13. In this variant embodiment, the depression 142 of the interface part 13 is understood in the longitudinal direction which can be found in the known interface parts 13 and the depression 142 located closer to the crosspiece 11 relative to the standard contact face. The depression 142 formed by the stamping extends along a vertical axis Z of the at least one interface part 13. Thus, the interface part 13 forms a first plane at the level of the slot 131 allowing access to the fixing member of the towing eye, and a second plane, located behind the first plane relative to the longitudinal axis X, the second plane comprising the device 14 formed by the depression 142.

In summary, the invention relates to an interface part 13 intended to be fixed integrally to a crosspiece 11 of a set of bumpers 1, the interface part 13 comprising a device 14 which can take the form of a through hole or of a depression 142 intended to be located directly behind a fixing system 212 of an access hatch 211 of a bumper skin 21 covering the crosspiece 11, the access hatch 211 authorizing the fixing of a towing eye on its fixing member, relative to a longitudinal axis X of the motor vehicle on which the interface part 13 is intended to be mounted.

Of course, the invention is not limited to the examples which have just been described and numerous adjustments can be made to these examples without departing from the scope of the invention. In particular, the different characteristics, shapes, variants and embodiments of the invention can be associated with each other in various combinations to the extent that they are not incompatible or exclusive of each other. In particular, all the variants and embodiments described above can be combined with each other.

Claims (8)

Rear bumper assembly (1) for a motor vehicle, the bumper assembly (1) comprising:
- a crosspiece (11) intended to extend transversely relative to the motor vehicle;
- a shock absorption system (12) configured to be able to absorb a rear shock transmitted by the crosspiece (11), the shock absorption system being integral with the crosspiece (11) at each of the lateral ends (111 ) of said crossmember (11), the shock absorption system (12) being intended to be fixed integrally to a rear spar of the motor vehicle;
- interface parts (13) each forming a non-zero angle with a rear face of the crosspiece (11) intended to be placed opposite a bumper skin (21) of the motor vehicle, the interface parts ( 13) being integral with the crosspiece (11) at its lateral ends (111);
characterized in that at least one of the interface parts (13) comprises, at a part intended to be located opposite an access hatch (211) to a member for fixing a ring of towing, a device (14) configured to allow a longitudinal clearance (DL) greater than 8 mm between a fixing system (212) of the access hatch (211) and said device (14). Bumper assembly (1) according to the preceding claim, in which the device (14) takes the form of an opening (141) formed in the at least one interface part (13), the opening (141) being located opposite the fixing system (212), relative to a longitudinal axis (X). Bumper assembly (1) according to the preceding claim, in which the opening (141) has a triangular shape dimensioned to allow contactless insertion of the fixing system (212) into the opening (141). Bumper assembly (1) according to claim 1, in which the device (14) takes the form of a stamping formed on the at least one interface part (13), so that the stamping forms a depression ( 142) located opposite the fixing system (212), relative to a longitudinal axis (X), said interface part (13). Bumper assembly (1) according to the preceding claim, in which the depression (142) formed by the stamping extends along a vertical axis (Z) of the at least one interface part (13). Bumper arrangement (2) comprising the set of bumpers (1) according to any one of the preceding claims and a bumper skin, the fixing system (212) of the access hatch (211) of the bumper skin (21) being located opposite the device (14) of the bumper assembly (1). Arrangement according to the preceding claim taken in combination with the set of bumpers (1) according to any one of claims 2 or 3, in which the opening (141) of the fixing system (212) of the access hatch ( 211) of the bumper skin (21) is located opposite the device (14) of the bumper assembly (1). Motor vehicle comprising a bumper arrangement according to any one of claims 6 or 7.