FR3070337A1 - SHOCK CONTROL ASSEMBLY COMPRISING AN EXTRUDED VEHICLE IMPACTOR - Google Patents

Abstract

The invention relates to a shock control assembly comprising a powertrain, a structural part of a motor vehicle that can move against the propulsion unit in the event of an impact, and an impactor (10), the impactor (10) comprising a surface impact (30) and force transmission positioned between the structural part and the power unit to which it is fixed by fixing means. This impactor (10) is made of extruded aluminum in a given extrusion direction (E) and comprises two main faces (A, B) perpendicular to the extrusion direction (E). In addition, this impactor (10) comprises a stiffening rib and force channel (34) extending from and perpendicular to the impact surface (30) and at least two through-cells (20) parallel to the direction extrusion (E) in which are housed the attachment means of the impactor (10).

Description

SHOCK CONTROL ASSEMBLY INCLUDING AN EXTRUDED VEHICLE IMPACTOR The invention relates to an impact control assembly comprising a powertrain (called GMP), a structural element of a motor vehicle and an impactor, this impactor ensuring transmission of effort between the structural element and the propulsion unit. This invention also relates to a method for producing such an impactor.

This invention relates to the field of safety of motor vehicles equipped with a powertrain. The term "powertrain" GMP designates an internal combustion engine group, or an electric motor group, which comprises the main components involved in the drivability of a vehicle: engine, gearbox, clutch, etc. This invention relates in particular to the retaining devices of a powertrain fitted to a vehicle, in order to control the movements thereof during an impact, and to prevent impacts with the occupants of the vehicle, for example by its intrusion into the passenger compartment of this vehicle.

Impactors are additional structures intended to absorb shocks, for example by carrying out a controlled local deformation of the cradle supporting the engine, this deformation transforming part of the initial kinetic energy of the vehicle and directing possible displacement of the engine in steering to maintain the integrity of the passenger compartment and therefore of its occupants. To perform this function, an impactor is impact resistant and is rigidly fixed, this fixing being generally provided on an element such as a casing of an element of the GMP.

An example of the use of such an impactor is presented with reference to FIG. 1. In this figure, a motor vehicle impactor 1 comprises screws 2 for fixing this impactor 1 to a structural element of the vehicle ( gearbox housing, engine, cradle, etc.). This impactor 1 also includes an impact face 3, intended to receive a thrust from a front part of the vehicle in the event of a frontal impact and deformation of the front part of the vehicle. This front part generally consists of two longitudinal members connected by a cross member forming part of the structure of the motor vehicle.

Many solutions have contributed to improving the impactors. Thus patent FR 2976251 presents an impactor fixed on a structural part and which is partially housed in a cavity arranged in the powertrain in the event of an impact. And the document WO 20133121124 presents a relay bearing support for a motor vehicle transmission comprising a shock impactor produced in one piece with the support.

However, none of these solutions relates to improving the robustness and resistance of the impactors considered as a simple intermediate piece.

To overcome this drawback, the invention provides for using the qualities of profiled aluminum to form the impactor and form stiffened zones of resistance and of channeling of forces in the event of impact.

More specifically, the present invention relates to an impact control assembly comprising a powertrain, a structural part of a motor vehicle capable of moving against the powertrain in the event of an impact, and an impactor comprising a surface d impact and force transmission positioned between the structural part and the powertrain to which it is fixed by fixing means. In this assembly, the impactor is made of extruded aluminum in a given direction of extrusion and has two main faces perpendicular to the direction of extrusion. In addition, the impactor comprises at least one stiffening rib and force channel extending from and perpendicular to the impact surface with an angle situated in an interval of 90 ° +/- 15 ° relative to this surface, and at least two through cells parallel to the direction of extrusion in which are housed the means for fixing the impactor to the powertrain.

The advantage of extruded aluminum lies in particular in its strength and ductility which are significantly higher than that of cast aluminum, which allows for light technical parts, with good impact resistance , in particular in the form of ribs which channel the forces.

The structural part can be a cradle of the engine group, a rack or a steering box, or any part capable of transmitting a force between the body and the powertrain during an impact.

According to advantageous characteristics:

- The impactor comprises a single rib formed between two through openings and extending in a median plane perpendicular to the impact surface;

- The impactor comprises several ribs extending from the impact surface, these ribs belonging to a star network of ribs separated by through openings;

- the cells are circular and the openings are elongated, these cells and openings being distributed throughout the impactor;

- the configuration of the impact surface is chosen between plane, convex curved, concave curved, and protruding, such configurations making it possible to adapt to predictable shocks;

- The impactor has a contour which at least partly follows the external shape of a face of the powertrain of determined external shape;

- the through openings are determined in number, volume and position so that the impactor has walls of the same thickness.

The invention also relates to a motor vehicle equipped with an assembly comprising a powertrain, a structural part of a motor vehicle, and an impactor fixed to the powertrain as defined above.

The invention also relates to a method for producing a series of impactors such as that defined above. This process includes the following steps:

- Prepare an extrusion die comprising circular cores and elongated cores in order to form, after extrusion, cells for fixing means as well as elongated openings, to form at least one rib between two openings perpendicular to a surface of impact;

- determine the width of the impactors to be produced;

- extrude aluminum, and

- cut the extruded aluminum to widths equal to the determined width and separate the impactors from the series thus produced.

According to advantageous characteristics, the circular and elongated cores are positioned so that the fixing cells and the openings formed during the extrusion are distributed in each impactor so that each impactor has walls of the same thickness.

In the figures, identical elements are identified by the same reference sign which refers to (x) passage (s) of the description which mentions it (s).

Other data, characteristics and advantages of the present invention will appear on reading the following non-limited description, with reference to the appended figures which represent, respectively:

- Figure 1, a view of an impactor according to the state of the art (already presented);

- Figure 2, a perspective view of an example of an impactor according to the invention, in the nominal position under a motor vehicle hood;

- Figure 3, a perspective view of a housing of an element of the powertrain on which the impactor is fixed according to Figure 2;

- Figure 4, a perspective view of another example of an impactor according to the invention, in the nominal position under a motor vehicle hood; and

- Figures 5 and 6, perspective views of other examples of impactors according to the invention.

Figure 2 shows a perspective view of an exemplary impactor 10 according to the invention, the shape of which has been designed for an electric motor. This impactor 10 is made of extruded aluminum and has an impact surface 30 and two circular through cells 20 distributed throughout the impactor 10, these cells 20 serving to house fixing screws 21 (cf. FIG. 3). The extrusion die and its direction of flow "E" define a through direction, perpendicular to the two parallel main faces "A" and "B" of the impactor 10, all the other internal or external surfaces of the impactor 10 extending transversely, that is to say perpendicular to said main faces "A" and "B".

The impact surface 30 is flat in this embodiment, and extends between the main faces "A" and "B". In other embodiments, this impact surface can be convex convex, concave convex, or even protruding. Such configurations make it possible to adapt the impactor 10 to a predictable shock as a function of the configuration of the part capable of causing this shock. Through openings of elongated shape 32 and 33 are distributed throughout the impactor 10 in order to reduce the weight and to distribute the mass of the impactor 10 in a substantially homogeneous manner by forming walls of the same thickness, these walls constituting the armature of the impactor 10. In addition, this distribution is configured to form a central wall forming a rib 34. This rib 34 extends between the two through openings 32 and 33 in a median plane Pm, substantially perpendicular to the surface impact 30 in the middle with a tolerance of up to +/- 15 °, or slightly beyond. This position of the rib 34 makes it possible to reinforce the rigidity of the impactor 10 and to channel the efforts to facilitate their transmission in the event of an impact against the impact surface 30.

The perspective view of Figure 3 shows the impactor 10 in situation under a motor vehicle hood, fixed to a housing of the GMP 40. Screws 21, inserted in the cells 20 (see Figure 2), fix the impactor 10 on this casing 40. The impactor 10 is placed facing the front of the motor vehicle, in a position ready to withstand, during a violent impact, a force transmission between the engine cradle 41 (cf. Figure 4) and the GMP 40 housing.

The perspective view of Figure 4 illustrates a perspective view of another example of an impactor 10 ′ according to the invention, in the nominal position under a hood of a motor vehicle. The impact surface 30 'is placed between the engine cradle 41 and a casing of the GMP 40 to which the impactor 10' is fixed as in FIG. 3. In this impactor 10 'of generally triangular shape, a star network of radial ribs 42 made of extruded aluminum, separated by elongated through openings 43, connects the contour faces of the impactor 10 'to a center 4. In particular, in this example, three ribs 42 extend from the impact surface 30 'of convex shape and substantially perpendicular to this surface 30'.

This network of ribs 42 ensures an optimized distribution of stresses in the event of an impact. Indeed, during an impact, the impactor 10 ’transmits a force to the cradle and / or limits the movement of the GMP 40 in order to avoid an intrusion of the GMP 40 into the passenger compartment of the motor vehicle. In this case, the engine cradle 41 comes into contact with the impact surface 30 'of the impactor 10', and the shock wave is distributed over the casing 40 to which the impactor 10 'is fixed, which decreases noticeably the constraints. More generally, different forms of impactor are produced depending on the different powertrains manufactured.

Other embodiments of impactors 50 and 60 are presented respectively with reference to the perspective views of FIGS. 5 and

6. These impactors 50 and 60 have contour faces, respectively 56 and 66, which conform to the shape of the parts of the powertrain to which these impactors 50 and 60 are fixed.

The impactor 50 (see FIG. 5) comprises three circular cells 51 serving as housing for fixing screws, and three through openings of elongated shape 52, 53, 54 distributed between the circular cells 51 to reduce the weight of the impactor 50 and distribute the masses. The impactor 60 (cf. FIG. 6) also comprises three circular cells 61 for housing the fixing screw, and four through openings of elongated shape 62 to 65 distributed between the circular cells throughout the impactor 50.

Advantageously, two through openings, respectively 52 and 53 for the impactor 50, 62 and 63 for the impactor 60, form ribs 57 and 67 respectively, extending in a mean plane Pm substantially perpendicular to the surface d 'impact, respectively the surfaces 5 and 6. In the event of an impact, the ribs 57 and 67 reinforce the rigidity of the impactor, respectively 50 and 60, and channel the forces to promote their transmission.

The invention is not limited to the embodiments described and shown. Thus, the number of circular cells, and corresponding fixing means, as well as the number of transverse openings can be greater than three. The number of ribs perpendicular to the impact surface can be two or more than three. Furthermore, in addition to the screws, the means for fixing the impactor may be bolts, clips, rivets or the like. In addition, the or each stiffening rib and force channel 10 extends substantially perpendicular to the impact surface at an angle which can be in the range 90 ° +/- 15 °, for example + / -5 °.

Claims (10)

claims 1. Shock control assembly comprising a powertrain (40), a structural part (41) of a motor vehicle capable of moving against the powertrain (40) in the event of an impact, and an impactor (10; 10 ′, 50; 60), this impactor (10; 10 ', 50; 60) comprising an impact (30, 30', 5, 6) and force transmission surface positioned between the structural part (41) and the powertrain (40) to which it is fixed by fixing means, characterized in that the impactor (10; 10 ', 50; 60) is made of extruded aluminum in a given direction of extrusion (E) and comprises two main faces (A, B) perpendicular to the direction of extrusion (E), and in that the impactor (10; 10 ', 50; 60) comprises at least one stiffening rib and force channel (34 , 43, 57, 67) extending from and perpendicular to the impact surface (30, 30 ', 5, 6) with an angle within an interval of 90 ° +/- 15 ° with respect to this surface, and at least two through cells (20, 51, 61) parallel to the direction of extrusion (E) in which are housed the fixing means (21) of the impactor ( 10; 10 ', 50; 60) to the power train (40). 2. shock control assembly according to claim 1, wherein the impactor (10, 10 ', 50; 60) comprises a single rib (34) formed between two through openings (32, 33) and extending in a median plane (Pm) perpendicular to the impact surface (30). 3. shock control assembly according to claim 1, in which the impactor (10 ′) comprises several ribs (42) extending from the impact surface (30j, these ribs (42) belonging to a star network of ribs (42) separated by through openings (43). 4. shock control assembly according to any one of the preceding claims, wherein the cells (20; 51; 61) are circular and the openings (32, 33; 43; 52 to 54; 62 to 65) of elongated shape , these cells and openings being distributed throughout the impactor (10; 10 ', 50; 60). 5. Impact control assembly according to any one of the preceding claims, in which the configuration of the impact surface (30, 30 ’, 5, 6) is chosen between plane, convex curved, concave curved, and protruding. 6. shock control assembly according to any one of the preceding claims, in which the impactor (10; 10 ′, 50; 60) has a contour (56, 66) which at least partially matches an external shape of the group power train (40). 7. shock control and control assembly according to any one of claims 2 to 6, in which the through openings (32, 33; 52 to 54; 62 to 65) are determined in number, in volume and in position so that the impactor (10; 10 ', 50; 60) has walls of the same thickness. 8. Motor vehicle, characterized in that it comprises a powertrain (40), a structural part (41) of a motor vehicle, and an impactor (10; 10 ', 50; 60) fixed to the powertrain (40) according to any one of the preceding claims. 9. Method for producing a series of impactors (10; 10 ’, 50; 60), characterized in that it comprises the following steps: - preparing an extrusion die comprising circular cores and elongated cores in order to form, after extrusion, cells (20, 51, 61) for fixing means (21) as well as elongated openings, to form at least one rib (34, 43, 57, 63) between two openings (32, 33; 52 to 54; 62 to 65) perpendicular to an impact surface (30, 30 ', 5, 6); - determine the width of the impactors (10; 10 ’, 50; 60) to be produced; - extrude aluminum, and - cut the extruded aluminum to widths equal to the determined width and separate the impactors (10; 10 ’, 50; 60) from the series thus produced. 10. Method for producing a series of impactors (10; 10 ′, 50; 60) according to the preceding claim, in which the circular and elongated cores are positioned so that the fixing cells (20, 51,61) and the openings (32, 33; 52 to 54; 62 to 65) formed during the extrusion are distributed in each impactor (10; 10 ', 50; 60) so that each impactor (10; 10', 50; 60) has walls (34, 43, 57, 67) of the same thickness.