EP4565438A1

EP4565438A1 - Improved cross-member for a heavy vehicle suspension system

Info

Publication number: EP4565438A1
Application number: EP23753994.5A
Authority: EP
Inventors: Michael GUNGL; Fabian Schmidt; Christian Konrad; Florian Koeberle
Original assignee: Iveco SpA
Current assignee: Iveco SpA
Priority date: 2022-08-03
Filing date: 2023-08-01
Publication date: 2025-06-11
Also published as: IT202200016545A1; WO2024028767A1

Abstract

Vehicle provided with a suspension system (4) configured to operatively connect an electric axle (5) of a heavy vehicle to a chassis (1) thereof and comprising a cross-member (20) and at least an air spring (8), the cross- member (20) comprising a pair of lateral elements (21) each connected to a respective side members (2, 3) of a chassis (1) of the vehicle in a direction along an axis (B) transversal with respect to a longitudinal axis (A) of the chassis (1), the lateral elements (21) each comprising a fixation portion (21') configured to fix the lateral element (21) to said the members (2, 3), the lateral elements (21) each comprising a coupling portion (21'') extending from said fixation portion (21') and configured to define a terminal portion (29) opposite to the fixation portion (21'), the lateral elements (21) each defining a support portion (35) configured to provide at least a fixation point (36) for coupling the air spring (8) to the chassis (1).

Description

" IMPROVED CROSS-MEMBER FOR A HEAVY VEHICLE SUSPENSION

SYSTEM"

Cross-Reference to Related Applications

This Patent Application claims priority from Italian Patent Application No . 102022000016545 filed on August 3 , 2022 , the entire disclosure of which is incorporated herein by reference .

Technical Field

The present invention concerns a cross-member for a suspension system, in particular a cross-member for a heavy vehicle suspension system provided with an electronic traction .

Background of the Invention

Heavy vehicles such road transport vehicles , e . g . trucks , are more and more electri fied for reducing their polluting emissions . In particular, such vehicles may be hybrid vehicles or purely electric vehicles .

In particular, the electri fied vehicles comprises at least an electric axle , i . e . an axle provided with electric machines such as motors/generators configured to impart a torque on the axle to allow its motion or to recharge battery modules of the vehicle when this latter is braking .

Such battery modules are usually placed in the proximity of the electric machines of the electric axle in order to provide energy exchange with electric machines in an ef ficient way .

However, as known, an axle of a vehicle is connected to the chassis of this latter via a suspension system configured to dampen the forces acting between the road and the chassis .

I f a vehicle is provided with an electric axle as described above , the presence of the electric batteries increases the encumbrance around the chassis .

In particular, suspension systems comprises air springs that need peculiar brackets to allow their fixation to the axle . However, such brackets are bulky and waste useful space .

Moreover, the presence of further peculiar fixing means for stably connecting the electric batteries to the chassis reduces the useful space on the vehicle for the elements of the suspension .

Therefore , the need is felt to provide a compact and economic way to allow the fixation of the suspension elements of a heavy vehicle and to allow suf ficient space to house the electronic batteries in the proximity of an electric axle of the such heavy vehicle .

An aim of the present invention is to satis fy the above mentioned needs in a compact , optimi zed and cost ef fective way .

Summary of the Invention

The aforementioned aim is reached by a vehicle as claimed in the appended independent claims .

Preferred embodiments of the invention are reali zed according to the claims dependent on or related to the above independent claim .

Brief Description of Drawings

For a better understanding of the present invention, a preferred embodiment is described in the following, by way of a non-limiting example , with reference to the attached drawings wherein :

• Figure 1 is a perspective view showing a portion of a suspension system for an electric axle of a heavy vehicle comprising a cross-member according to the invention;

• Figure 2 is a perspective enlarged view of a portion of the suspension system of figure 1 ;

• Figure 3 is a top enlarged view of a portion of the suspension system of figure 1 ; and • Figure 4 is perspective enlarged view of a cross-member according to the invention .

Detailed Description of the Invention

Figure 1 shows a portion of a chassis 1 of a heavy vehicle such as truck, comprising as known a pair of side members 2 , 3 extending longitudinal along a longitudinal axis A of the vehicle .

The chassis 1 is connected via a suspension system 4 , partially shown, to an electric axle 5 . As per se known, the suspension system 4 dampens the relative movements between the chassis 1 and the electric axle 5 that is configured to provide torque to wheels , not shown, carried by the electric axle 5 itsel f .

The chassis 1 is furthermore configured to carry at least one battery module 6 configured to be electrically connected to the electric axle 5 to exchange electric energy . In particular, as known, the electric axle 5 is provided with electric machines that are fed by the at least one battery module 6 to provide torque to the wheels carried by the axle 5 or to receive electric energy generated by the electric machines when the vehicle is braking .

In the exemplarily shown embodiment , the chassis 1 carries a battery module 6 housed between the side members 2 , 3 and in a rear position with respect to electric axle 5 and further battery modules 6 carried by a respective side member 2 , 3 outside with respect the side members 2 , 3 and aligned to the battery module 6 housed between the side member .

The suspension system 4 comprises , as known, a plurality of elements configured to connect the electric axle 5 to respective side members 2 , 3 in order to dampen/ limit a relative movement along a direction along axis A or a di f ferent axis .

In particular, the proposed suspension system 4 may essentially comprise , for each among a left and right side corresponding to left and right side members 2 , 3 :

• a metallic beam 7 comprising a front and a rear terminal portions along said longitudinal axis A of the vehicle and an intermediate portion comprised between these latter;

• a pair of air springs 8 operatively interposed between the front and rear terminal portions and the respective side member;

• a damper 9 operatively interposed between said intermediate portion and the respective side member ;

• a longitudinal retaining element (not shown) operatively interposed between the metallic beam 7 and a front hanger 11 fixedly carried by the respective side member;

• a transversal retaining element 12 operatively interposed between the axle 5 and said chassis 1 ; and

• a stabilizer bar 13 operatively interposed between the metallic beam 7 and chassis 1 , e . g . via a movable connection 14 not further described into detail .

In particular, the transversal retaining element 12 comprises a V-rod element provided with two inclined arms 12 ' , 12 ' ’ with respect to axis A and configured to limit a movement on a transversal axis perpendicular to axis A.

No further details will be provided to the suspension system for sake of brevity . Indeed, clearly, the suspension system comprises other elements here not shown and described for simplicity .

In particular, as per se known, the air springs 8 comprises an air bellow that is fixedly carried by the respective side member 2 , 3 as detailed in the following .

In particular, according to the invention, transversal retaining element 12 and the air springs 8 are connected to side members 2 , 3 via a cross-member 20 as shown in detail in figures 2 and 3 . The cross-member 20 extends transversally along a transversal axis B , preferably perpendicularly with respect to longitudinal axis A.

Accordingly, the cross-member 20 comprises a pair of lateral elements 21 configured to allow the connection of the side members 2 , 3 of chassis 1 and to allow the connection of the at least one battery module 6 and a central element 22 configured to stably connect together the lateral elements .

In greater particular, the lateral elements 21 are advantageously equal , i . e . they have a shape symmetrical with respect to longitudinal axis A.

In particular, referring to only one of the lateral elements 21 , being the other equal , it comprises a fixation portion 21 ' configured to allow the fixation of the lateral element 21 to the respective side member 2 , 3 and a coupling portion 21 ' ’ configured to allow the fixation of the lateral element 21 to the central element 22 .

In particular, the fixation portion 21 ' is a compri ses a bi furcated element comprising a pair of fixation plates 23 and a pair of arms 24 connecting the fixation plates 23 to the coupling portion . In particular, each fixation plate 23 defines a plurality of holes configured to allow the insertion of a fixation element , not shown, such as a threaded element or a dowel to f ix the fixation portion 21 to the side member 2 , 3 .

Preferably, the longitudinal extension of the front fixation plate 23 is greater than the longitudinal extension of the rear fixation plate 23 with respect to the coupling portion 21 ’ ’ .

It is noticed that arms 24 diverges from the coupling portion 21 ' ’ with a Y-shape , i . e . one diverges rearwardly with respect to coupling portion 21 ' ’ and the over diverges frontward with respect to the coupling portion 21 ' ' .

The Each lateral element 21 further defines a seat 26 that realized between an arm 24 and the coupling portion 21' ’ via a recess 27 realized therebetween and opened towards the electric axle 5.

The 26 is configured to accommodate a portion of a respective arm 12' , 12' ’ of the transversal retaining element 12 of the suspension system 4 a hinge connection 28 housed in seat 26 between arm 24 and the coupling portion 21' ’ .

As said, the cross-member 20 advantageously comprise a central element 22 suitable to be connected to the lateral element 21 via the aforementioned coupling portions 21' ' .

In particular, the coupling portion 21' ’ defines a terminal portion 29 provided with a plurality of openings, e.g. at least two holes, configured to allow the connection of the central element 22 via a fixation element such as a threaded element, e.g. a bolt, or any other equivalent fixation element such as a dowel.

In particular, the terminal portion 29 extends parallel to longitudinal axis, i.e. transversally to the coupling portion 21' ' . Therefore, the lateral elements have substantially a "capital Y" shape".

In the disclosed example of the central element 22 comprises a pair of connection elements 31, namely an upper connection element 31 and a lower connection element 31 spaced apart about a vertical axis perpendicular to axis A and B .

More in detail, each connection element 31 essentially comprises a plate-like element realized in a material that preferably is different with respect to the material of lateral elements 21.

Preferably, the lateral elements 21 are made of cast iron and they are made of a single piece and each connection element 31 is made of steel.

The presence itself of central element 22 and, when present, the thickness of each connection element 31 or their number or their overall shape may be varied to vary the stiffness of the cross-member 20, i.e. to vary the mechanical properties of the connection between the side members 2,3.

Each lateral element 21 further defines a support portion 35 configured to provide at least a connection point 36 to the aforementioned air springs 8, i.e. to air bellows.

In particular, the support portion 35 extends from one of the fixation plates 23 and in particular by the front fixation plate 23 and comprises at least one arm 35' , 35' ’ .

The at least one arm 35' , 35' ’ is arcuated and defines a concavity towards ground and is configured to jump over the transversal extension of the side member 2, 3 starting from the fixation plate 23.

In detail, the support portion according to the present invention comprises a pair of arms 35' , 35' ’ distances along longitudinal axis A in a diverging manner along transversal axis B, i.e. getting away from fixation plate 23.

The arms 35' , 35' ’ defines the contact point 36 at a terminal portion thereof that is substantially parallel to ground .

The contact point 36 may be a point of axial contact with the air spring 8 or a fixation point provided with a opening to allow the insertion of a fixation element to fix the air spring to this latter.

The suspension system 4 may further comprise, in particular in case contact point 36 have merely contact function and no fixation function, a fixation bracket 37 fixedly carried by side member 2, 3 outside the transversal space comprised therebetween and configured to fix the air spring 8 to the side member 2, 3.

Each lateral member 11 further define at least a fixation point 40 configured to allow the fixation of the battery module 6 to the lateral element 21, i.e. to the respective side member 2, 3. In particular, the fixation point 40 comprise a protuberance that extends getting away from at least one of the lateral element 21 portions to allow the insertion of a fixation element such as a threaded element or a dowel .

Preferably, the fixation point is reali zed in the s ide of the lateral element 21 oppos ite to the one carrying the support portion 35 for the air spring 8 .

The operation of the described cross-member 20 is the following .

When fixed via holes to the respective side member 2 , 3 , the cross-member 20 can be used to securely provide a support to air springs 8 and to support the battery module 6 to the chassis 1 in a simple and quick way

In view of the foregoing, the advantages of a suspension system and a vehicle comprising such cross-member 20 according to the invention are apparent .

The proposed cross-member 20 allows at the same time the connection in a transversal direction with respect to axis A of side members and the securing of the air spring elements .

Therefore existing brackets voted to such aim may be eliminated, thereby reducing their encumbrance , their cost and the manufacturing time .

Furthermore , the proposed shape provides good fixation points to the air spring 8 and, at the same time , a good robustness of the support portion and, in general , of the cross-member .

Furthermore , the mounting of the battery module 6 is simpli fied because of the possibility of mounting separately the lateral elements and the central element .

Moreover, the central element may be designed in order to vary the overall transversal sti f fness of chassi s , i . e . between the side members 2 , 3 .

Indeed, a thicker central element or a central element comprising multiple connection elements would provide a more sti f f cross-member and vice-versa .

The above advantage is particularly useful in electric traction vehicles wherein the dimensions and weight of battery modules may vary and therefore the sti f fness required to the chassis may vary accordingly .

Furthermore , the proposed lateral elements further allows the fixation of battery modules thereby further increasing the versatility of the cross-member and reducing the need of peculiar fixation means .

It is clear that modi fications can be made to the described suspens ion system and vehicle comprising a crossmember, which do not extend beyond the scope of protection defined by the claims .

For example , the support portion or the fixation portion may have di f ferent shapes , allowing a plurality of fixation holes according to the speci fic fixation way of the battery module .

Similarly, the material and number of elements of the central element may be varied according to the design request of the heavy vehicle .

Moreover, the overall described portions of the crossmember may be varied according to the typology of suspension system .

Claims

1.- Vehicle comprising a chassis (1) and an electric axle (5) operatively connected to said chassis (1) , said heavy vehicle comprising at least a battery module (6) configured to be electrically connected to said electric axle (5) , said heavy vehicle comprising a suspension system (5) for connecting said electrical axle (5) to said chassis (1) , said suspension system (4) comprising a cross-member (20) and at least an air spring (8) , said cross-member (20) comprising a pair of lateral elements (21) each connected to a respective side members (2, 3) of said chassis (1) in a direction along an axis (B) transversal with respect to a longitudinal axis (A) of said chassis (1) , said lateral elements (21) each comprising a fixation portion (21' ) configured to fix said lateral element (21) to said side members (2, 3) , said lateral elements (21) each comprising a coupling portion ( 21 ’ ’ ) extending from said fixation portion (21' ) and configured to define a terminal portion (29) opposite to said fixation portion ( 21 ’ ) , said lateral elements (21) each defining a support portion (35) configured to provide at least a contact point (36) for coupling said air spring (8) to said chassis (1) .

2.- Vehicle according to claim 1, wherein said lateral elements (21) each defines a seat (26) configured to house a hinge connection (28) with a suspension element (12) of said suspension system (4) of said vehicle.

3.- Vehicle according to claim 1 or 2, wherein said lateral elements (21) each defining at least a fixation point (40) configured to secure a battery module (6) of said heavy vehicle to said chassis (1) .

4.- Vehicle according to any of the preceding claims, wherein said lateral elements (21) are symmetric with respect to longitudinal axis (A) of said vehicle.

5.- Vehicle according to any of the preceding claims, wherein said fixation portion (21' ) comprises a bifurcated element provided with a pair of fixation plates (23) connected to a pair of arms (24) to the coupling portion ( 21 ’ ’ ) and configured to allow the fixation of fixation portion (21' ) to the chassis (1) .

6.- Vehicle according to claim 5, wherein said fixation portion (21' ) has a Y-shape.

7.- Vehicle according to any of claims 5 or 6, wherein said support portion (35) is carried by one of said fixation plates (23) .

8.- Vehicle according to claim 7, wherein said support portion (35) comprises at least an arcuated arm (35' , 35' ’ ) extending by said fixation plate (23) and defining said contact point (36) on the opposite extremity thereof.

9.- Vehicle according to claim 7 or 8, wherein said support portion (35) comprises two arcuated arms (35' , 35' ’ ) extending by said fixation plate (23) and defining a respective fixation point (36) on the opposite extremity thereof, said arms (35' , 35' ’ ) diverging one with respect to the other along said longitudinal axis (A) .

10.- Vehicle according to claims 8 or 9, wherein said at least one arm (35' , 35' ’ ) defines a concavity directed towards ground and configured to extend transversally over the respective side member (2, 3) .

11.- Vehicle according to any of the preceding claims, wherein said lateral element (21) is realized as one piece.

12.- Vehicle according to any of the preceding claims, wherein said seat (26) is comprised in a transversal direction between said fixation portion (21' ) and said terminal portion (29) .

13.- Vehicle according to any of the preceding claims, wherein said cross-member (20) further comprises a central element (22) configured to be connected to the respective terminal portion (29) of each lateral element (21) .

14.- Vehicle according to claim 13, wherein said central element (22) comprises at least a connecting element (31) .

15.- Vehicle according to claim 13 or 14, wherein said central element (22) comprises an upper and a lower connecting elements (31) spaced apart along a vertical axis.