FR3089885A1 - VEHICLE DRIVE UNIT WITH DRIVE ELECTRIC MACHINE SUPPORTED BY A STRUCTURAL ELEMENT AND COUPLED TO A CROSSBAR - Google Patents

Abstract

A powertrain equips a vehicle and includes an electric motor machine (ME) coupled to a cross-member (TS) fixedly fixed to structural elements (ES1). This electric motor machine (ME) comprises a lower part (PI) supported by at least one other structural element (ES3) via two filtering parts (PF) filtering the vibrations which it (ME) induces, and an upper part (PS ) coupled to the cross-member (TS) via at least one torque recovery element (ERC). Figure 2

Description

Description

Title of the invention: VEHICLE DRIVE GROUP WITH ELECTRIC DRIVE MACHINE SUPPORTED BY A STRUCTURAL ELEMENT AND COUPLED TO A CROSSBAR

Technical field of the invention

The invention relates to powertrains which equip certain vehicles and which include an electric drive machine coupled to a cross member.

It will be noted that in what follows, the term “electric motor machine” means an assembly that is integral and produces torque intended to move a vehicle from stored electrical energy.

State of the art

Certain powertrains (or GMPs) of vehicles, generally of the automobile type, comprise an electric drive machine which is coupled, via elastomer parts, on the one hand, to a crossmember (or beam) fixedly secured, either directly , or indirectly via intermediate parts, to structural elements, such as for example stretchers, and, on the other hand, to at least one other structural element, such as for example a cradle. Note that the cross member can also sometimes serve as a fixed anchor for at least one other piece of equipment, such as at least part of the power electronics.

Many architectures for coupling the electric drive machine have been proposed. They are generally called "horizontal architecture" or "radial architecture" or even "vertical architecture".

The invention relates more particularly to the vertical coupling architecture in which the electric motor machine can, for example, be suspended by its upper part from the crossmember via two filtration parts and coupled by its lower part to at least one structural element via one or more torque recovery elements. Such a coupling architecture is for example described in patent document CN 101537784. The two filtration parts (or “carrier blocks”) ensure both a resumption of the weight of the electric motor machine for vertical stresses and a resumption of torque (or anti-torque) for longitudinal stresses. Each torque recovery element (which can be an anti-torque link (comprising an articulation coupled to a structural element and an articulation coupled to the lower part of the electric motor machine) or else a simple articulation) ensures weight recovery for longitudinal stresses.

When using simple anti-torque joints installed near the vertical plane passing through the load-bearing wedges, the movement of the electric motor under torque recovery is purely in the longitudinal direction as the recovery efforts of torque, and only the recovery of the weight of the electric motor machine during vertical accelerations generates vertical forces (which can be minimized by putting a very low vertical stiffness compared to the vertical stiffness of the load blocks).

When using simple anti-torque joints distant from the vertical plane passing through the load-bearing blocks, the movement of the electric drive machine under torque recovery is contained in a plane defined by the longitudinal and vertical directions just like the torque recovery efforts.

When using at least one anti-torque link remote from the vertical plane passing through the load shims, the movement of the electric motor under torque recovery is contained in a plane defined by the longitudinal and vertical directions but the torque recovery efforts are oriented only in the axis of the link (most often along the longitudinal direction of the vehicle) just like the direction of the torque recovery efforts on the load-bearing blocks, and the weight recovery linked to vertical accelerations seen by the electric drive machine does not generate any vertical force at the level of the link.

Furthermore, when the electric drive machine is installed in the front part of the vehicle, the longitudinal positioning of the cross member must take into account the location of the transmission chain and the longitudinal extension of the cross member must be dimensioned by compared to the efforts it undergoes (weight gain and torque recovery). However, the fixing of this cross member to the stretchers (right and left) can influence the behavior of the latter during an impact, a fortiori when the cross member is sized for the forces of the transmission chain (and therefore when it is particularly rigid). Consequently, it is advantageous to limit the right-of-way in the longitudinal direction of the fixing of the crosspiece on each stretcher (that is to say the longitudinal distance between the front and rear fastenings of the crosspiece on the stretcher, which is considered incompressible), and / or move the cross member as far as possible towards the rear of the vehicle so that it is fixed outside the deformation zone of the stretchers during an impact or at least in the rear part of this deformation zone.

However, a retracted position of the cross member with a reduced grip in the longitudinal direction is not necessarily compatible with the location of the carrier blocks when the electric drive machine is sufficiently advanced in the front part of the vehicle. In fact, the load-bearing wedges are positioned in the longitudinal direction so that the center of gravity of the electric drive machine is close to the right connecting the two elastic centers of the load-bearing wedges in the plane defined by the longitudinal and transverse directions, thus allowing d '' avoid the tilting of the electric motor machine under its own weight, to improve the decoupling of the modes of the electric motor machine on its carrier blocks, and to avoid generating forces in the vertical direction during stresses in the longitudinal direction .

The load-bearing wedges, which take up the vertical forces (weight recovery), are currently installed in the longitudinal center of the crosspiece in order to avoid the generation of a torsional moment thereon and thus limit the influence of cross it on the stretchers. Indeed, fixing the load-bearing wedges in longitudinal overhang relative to the cross-member would generate a moment on the cross-member which would require an increase in its longitudinal grip on the stretchers, which would be counterproductive with respect to the need for shock due to the fact that this would increase the length of the incompressible zone on the stretchers.

The invention therefore aims in particular to improve the situation.

Presentation of the invention

To this end, it proposes in particular a powertrain intended to equip a vehicle and comprising an electric drive machine intended to be coupled to a crossmember fixedly fixed to structural elements of the vehicle.

This powertrain is characterized in that its electric drive machine comprises:

a lower part intended to be supported by at least one other structural element of the vehicle via two filtering parts filtering vibrations that its electric driving machine induces, and

- an upper part intended to be coupled to the cross-member via at least one torque recovery element.

Thus, there is a vertical coupling architecture allowing an implantation of the fairly advanced electric driving machine in a front part of a vehicle, and respecting the criteria for implantation of the filtering parts (or carrying blocks) screws. -with respect to the center of gravity of the electric drive machine and the compatibility of the cross-member with safety standards relating to shocks (i.e. with a fixing on the rear part of the structural elements (stretchers) and with a contained longitudinal right-of-way).

The powertrain according to the invention may include other characteristics which can be taken separately or in combination, and in particular:

- It may include two torque recovery elements secured in parallel to the crosspiece;

each torque recovery element can be intended to be coupled to the cross-member at a level which is identical to that to which this cross-member is fixedly fixed in the vehicle;

- Each torque recovery element can be secured in overhang to the cross;

- Each torque recovery element can be an anti-torque link;

• each anti-torque link can include a remote end of the cross member and installed in a vertical plane which is close to a vertical plane passing through the filtering parts and a center of gravity of the electric motor machine;

- As a variant, each torque recovery element can be an anti-torque articulation;

• each anti-torque joint can be installed in a vertical plane passing through the filtering parts and a center of gravity of the electric drive machine.

The invention also provides a vehicle comprising structural elements, a cross member fixedly secured to two of the structural members, and at least one powertrain of the type presented above and coupled to this cross member and to at least the one of these structural elements.

For example, at least the electric motor of this powertrain can be installed in an engine compartment located in a front part of the vehicle.

Brief description of the figures

Other characteristics and advantages of the invention will appear on examining the detailed description below, and the attached drawings, in which:

[Fig.l] illustrates schematically and functionally, in a top view, a first example of an architecture for coupling an electric motor machine of a powertrain according to the invention to structural elements of a vehicle ,

[Fig.2] schematically and functionally illustrates, in a view from the left side (in transparency), the coupling architecture of FIG. 1,

[Fig.3] illustrates schematically and functionally, in a top view, a second example of architecture for coupling an electric motor machine of a powertrain according to the invention to structural elements of a vehicle , and

[Fig.4] schematically and functionally illustrates, in a view from the left side (in transparency), the coupling architecture of Figure 3.

Detailed description of the invention

The invention particularly aims to provide a powertrain (or GMP) intended to equip a vehicle and comprising an electric drive machine ME supported by a structural element ES3 and coupled to a cross member TS which is itself fixedly secured to ESI and ES2 structural elements.

In what follows, we consider, by way of nonlimiting example, that the vehicle is of the automobile type. This is for example a car. However, the invention is not limited to this type of vehicle. It relates in fact to any vehicle comprising a GMP comprising an electric drive machine coupled to structural elements and to a cross member, and in particular land vehicles and maritime or river vehicles.

Furthermore, it is considered in what follows, by way of nonlimiting example, that the GMP is of the all-electric type, and therefore comprises an electric motor machine ME but no heat engine. But the invention is not limited to this type of GMP. It also indeed relates to hybrid GMPs, that is to say comprising at least one heat engine and at least one electric motor machine.

In addition, it is considered in the following, by way of nonlimiting example, that the electric motor machine ME of the GMP, the cross-member TS and the structural elements ESI to ES3 are intended to be installed in an engine compartment located in a front part of a vehicle.

In FIGS. 1 to 4, the direction X is a so-called longitudinal direction of the vehicle, which is parallel to the lateral sides of the latter, the direction Y is a so-called transverse direction of the vehicle, which is perpendicular to the direction X, and the direction Z is a so-called vertical direction, which is perpendicular to the longitudinal X and transverse Y directions. Furthermore, in FIGS. 1 to 4, the deformation zone of the ESI and ES2 stretchers during an impact (in the longitudinal direction X ) is materialized by the two-pointed arrow referenced zd.

We schematically illustrated in Figures 1 to 4 part of a GMP according to the invention, fitted to a vehicle (very partially shown). In fact, only the structural elements ESI to ES3 of the vehicle are here very schematically represented. For example, the first ESI and second ES2 structural elements can be what the skilled person calls left and right stretchers respectively, and the third structural element ES3 can be what the skilled person calls a cradle (it is generally installed substantially in the transverse direction Y of the vehicle). Here, the ES3 cradle includes two longitudinal extensions (or “long cradles”) left BL1 and right (e) BL2 which will be discussed later.

The GMP, according to the invention, comprises in particular an electric motor machine ME comprising lower parts PI and upper PS.

As best seen in Figures 2 and 4, the lower part PI is intended to be supported by at least the third structural element ES3 of the vehicle (for example the cradle) via two filtering parts (or carrier blocks) PF which are arranged so as to filter vibrations that its ME electric driving machine induces. These two filtering parts (or carrier blocks) PF, installed in the lower (or lower) part, ensure a resumption of the vertical forces in the vertical direction Z and a resumption of torque in the longitudinal direction X.

For example, and as illustrated without limitation in Figures 2 and 4, the two filtering parts (or carrier blocks) PF can be fixedly secured to the longitudinal extensions (or long cradles) left BL1 and right (e) BL2 of the third structural element (or cradle) ES3. As a variant, the two filtering parts (or supporting blocks) PF could be fixedly secured on a transverse part of the cradle which would connect the longitudinal extensions (or long cradles) left BL1 and right (e) BL2 by passing under the engine.

These two filtering parts (or carrier blocks) PF can, for example, be made of elastomer. This material indeed has a good capacity for filtering vibrations (induced by the ME electric driving machine), and its stiffness can be chosen according to needs. Furthermore, this material can be natural and / or synthetic.

The upper part PS is intended to be coupled to the cross member TS (and therefore in the upper part) via at least one ERC torque recovery element.

The ME electric driving machine thus has a vertical coupling architecture allowing it to be installed in a fairly advanced manner in a front part of a vehicle, and meeting the criteria for implanting the filtering parts (or carrying blocks) PF vis- opposite the center of gravity cg of the ME electric driving machine. In addition, this installation allows the TS crossmember to be compatible with safety standards relating to shocks, that is to say with a fixing on the rear part of the left structural elements (or stretchers) ESI and right ES2 and with a longitudinal and contained (or moderate) hold.

For example, and as illustrated without limitation in Figures 1 and 3, the GMP may include two elements of ERC torque recovery secured in parallel to the cross TS. The number of joints of ERC torque recovery elements is chosen as a function of the maximum torque of the electric driving machine ME and the more or less important need to distribute the forces on the cross-member TS.

Note that each ERC torque recovery element may be intended to be coupled to the cross member TS at a level (in the vertical direction Z) which is identical to that to which the cross member TS is fixedly secured in the vehicle. The forces being transmitted in the axis of the ERC torque recovery element, this makes it possible to have forces only in the longitudinal direction X.

Each ERC torque recovery element can present itself in at least two ways.

In a first way, illustrated in Figures 1 and 2, each ERC torque recovery element can be a simple anti-torque joint secured to the cross member TS. This connection can be made in a transverse edge before the cross member TS, or on a transverse edge before the cross member TS (and therefore in overhang as illustrated in FIGS. 1 and 2). The term “front transverse edge” is understood here to mean an edge of the cross member TS which is parallel to the transverse direction Y and oriented (here) towards the front face FA of the vehicle, which is secured to the front ends of the left ES 1 and right ES2 stretchers .

In the presence of this first way, each ERC anti-torque joint can, for example, be installed in a vertical plane pv passing through the filtering parts (or carrier blocks) PF and the center of gravity cg of the electric machine driving ME.

In a second way, illustrated in Figures 3 and 4, each ERC torque recovery element can be an anti-torque link. Each ERC anti-torque link then comprises a first end (rear), secured to the cross-member TS, and a second end (front), opposite this first end and secured to the upper part PS of the electric motor machine ME. These first and second ends respectively comprise first and second joints.

In the presence of this second way, each ERC anti-torque link can, for example, include a second end (front) distant from the cross member TS and installed in a vertical plane which is close to (possibly coincident with) the plane vertical pv passing through the filtering parts (or carrier blocks) PF and the center of gravity cg of the ME electric driving machine. Note that in practice this vertical plane is almost never confused with the vertical plane pv.

It will also be noted that each ERC torque recovery element can be secured in overhang to the TS cross member. This is particularly the case in the two examples illustrated respectively in Figures 1 and 2 and in Figures 3 and 4.

More specifically, in the first example illustrated in Figures 1 and 2, the ERC torque recovery elements (which are simple joints) are secured to PC coupling lugs, themselves fixedly secured to the TS cross member in two distant places by being aligned in the longitudinal direction X. It will be noted that these coupling lugs PC can be an integral part of the cross member TS (in particular when it is produced by molding or injection), or else be attached to this cross member TS, for example by screwing, gluing or welding.

This first arrangement is preferably used when the cross member TS is fixedly secured to the stretchers ES 1 and ES2 at a level which is relatively advanced in the longitudinal direction X. In this case, joints with low vertical stiffness are preferably used and positioned as close as possible to the vertical plane pv passing through the filtering parts (or carrier blocks) PF. Such a positioning makes it possible to have a displacement under torque recovery in the only longitudinal direction X, torque recovery efforts in the only longitudinal direction X, and a resumption of the weight of the electric driving machine ME during vertical accelerations (according to Z) generating vertical forces. These vertical forces can be minimized by putting a very low vertical stiffness with respect to the vertical stiffness of the filtering parts (or carrier blocks) PF.

In the second example illustrated in Figures 3 and 4, the ERC torque recovery elements (which are rods) have their first end (rear) which is secured in overhang to the TS cross member. For example, this connection can be made by means of an elastomer joint with a central metal insert and taken in the yoke and tightened by a through screw (this joint can be on the cross side or on the link side).

This second arrangement is preferably used when the cross member TS is fixedly secured to the stretchers ES 1 and ES2 at a level which is relatively moved back in the longitudinal direction X. In this case, use is preferably made of ECR rods having their first ends secured to the TS cross member away from the vertical plane pv passing through the filtering parts (or carrying blocks) PF. The displacement under torque recovery of the second ends of the ECR rods (ME side) is then contained in the XZ plane but the torque recovery forces are only in the axis of each ERC rod (substantially in the longitudinal direction X), and the direction of the torque recovery forces on the filtering parts (or carrier blocks) PF is also in the axis of each ERC link. In addition, the weight gain linked to the vertical accelerations seen by the ME electric driving machine does not generate any vertical force at the level of the ECR rods.

It will also be noted that the cross member (or beam) TS may possibly be part of the GMP. Furthermore, it (TS) can be made of a rigid plastic material (possibly with one or more inserts made of a metallic material). This metallic material can, for example, be an extruded aluminum, a foundry aluminum, or a steel (for example sheet metal).

The invention makes it possible to have a vertical architecture for coupling the ME electric driving machine which is optimized for shocks while respecting the functional needs of the suspension of this ME electric driving machine, namely the locations of its supports. and of the TS cross-member ideal in the event of impact and a distribution of the forces of the transmission chain allowing a more precise design of the components and interfaces.

Claims (1)

Claims [Claim 1] Powertrain for a vehicle, said powerplant comprising an electric drive machine (ME) intended to be coupled to a cross member (TS) fixedly secured to structural elements (ESI, ES2) of said vehicle, characterized in that said electric drive machine ( ME) comprises i) a lower part (PI) intended to be supported by at least one other structural element (ES3) of said vehicle via two filtering parts (PF) filtering vibrations which it (ME) induces, and ii) a upper part (PS) intended to be coupled to said cross-member (TS) via at least one torque recovery element (ERC). [Claim 2] Powertrain according to claim 1, characterized in that it comprises two torque recovery elements (ERC) secured in parallel to said crosspiece (TS). [Claim 3] Powertrain according to claim 1 or 2, characterized in that each torque recovery element (ERC) is intended to be coupled to said cross member (TS) at a level which is identical to that to which said cross member (TS) is fixedly attached in said vehicle. [Claim 4] Powertrain according to one of claims 1 to 3, characterized in that each torque recovery element (ERC) is secured in overhang to said crosspiece (TS). [Claim 5] Powertrain according to one of claims 1 to 4, characterized in that each torque recovery element (ERC) is an anti-torque link. [Claim 6] Powertrain according to claim 5, characterized in that each anti-torque link (ERC) comprises an end distant from said cross member (TS) and installed in a vertical plane which is close to a vertical plane passing through said filtering parts ( PF) and a center of gravity of said electric motor machine (ME). [Claim 7] Powertrain according to one of claims 1 to 4, characterized in that each torque recovery element (ERC) is an anti-torque joint. [Claim 8] Powertrain according to claim 7, characterized in that each anti-torque joint (ERC) is installed in a vertical plane passing through said filtering parts (PF) and a center of gravity of said electric motor machine (ME). [Claim 9] Vehicle comprising structural elements (ES1-ES3) and a cross member (TS) fixedly secured to two (ESI, ES2) of said structural elements (ES1-ES3), characterized in that it comprises at least one powertrain according to one of the preceding claims and coupled to said cross member (TS) and to at least Tun (ES3) of said structural elements (ES1-ES3). [Claim 10] Vehicle according to claim 9, characterized in that said electric drive machine (ME) of this powertrain is installed in an engine compartment located in a front part.