CN116438088A

CN116438088A - Improved suspension system for heavy vehicles

Info

Publication number: CN116438088A
Application number: CN202180072334.8A
Authority: CN
Inventors: 克里斯蒂安·康拉德; 弗洛里·克贝勒; 迈克尔·贡格尔; 法比安·施密特
Original assignee: Iveco Magirus AG
Current assignee: Iveco Magirus AG
Priority date: 2020-10-22
Filing date: 2021-10-22
Publication date: 2023-07-14
Also published as: EP4232305A1; WO2022084938A1; IT202000025021A1

Abstract

Suspension system (1) for a heavy vehicle, which suspension system is configured to connect an axle (2) of the heavy vehicle to a chassis (3), the axle (2) extending along a transverse axis (B) with respect to a longitudinal axis (a) of the vehicle, which suspension system comprises, among other elements, a stabilizer bar (35) operatively interposed between a metal beam (7) and the chassis (3), wherein the stabilizer bar (35) is placed under the axle (2) and the metal beam (7), a straight portion (35 ') of the bar (35) being supported by the metal beam (7) via a support means (36), and wherein a terminal portion (35') of the stabilizer bar (35) is supported in a freely rotatable manner by a front cradle (32) via a connection assembly (38).

Description

Improved suspension system for heavy vehicles

Cross Reference to Related Applications

This patent application claims priority from italian patent application No.102020000025021 filed on 10/22 2020, the entire disclosure of which is incorporated herein by reference.

Technical Field

The present invention relates to suspension systems for heavy vehicles, in particular for heavy vehicles provided with an electronic retractor.

Background

Heavy vehicles such as road transport vehicles, e.g. trucks, are becoming increasingly electrified for reducing their polluting emissions. In particular, these vehicles may be hybrid vehicles or pure electric vehicles.

In particular, electrified vehicles include at least one electrically driven rear axle, i.e., a rear drive axle provided with an electric machine such as a motor/generator configured to apply torque on the axle to permit movement of the axle or to charge a battery module of the vehicle while the vehicle is braking.

Such battery modules are typically placed in proximity to the motor of the electric axle to provide for energy exchange with the motor in an efficient manner.

However, as is known, the axles of the vehicle are connected to the chassis of the vehicle via a suspension system configured to dampen forces acting between the road and the chassis.

If the vehicle is provided with an electric axle as described above, the presence of the battery increases the barrier around the chassis.

Therefore, the known suspension systems for heavy vehicles are unsuitable due to the presence of the electric axle.

Accordingly, there is a need to provide a new arrangement of suspension system that can be mounted to an electric axle and that provides at least the same mechanical properties as known suspension systems.

The object of the present invention is to meet the above-mentioned needs in a compact, optimized and cost-effective manner.

Disclosure of Invention

The foregoing objects are achieved by a suspension system and a vehicle as claimed in the appended independent claims.

Preferred embodiments of the invention are achieved in accordance with claims dependent on or related to the above independent claims.

Drawings

For a better understanding of the invention, preferred embodiments are described below by way of non-limiting example with reference to the accompanying drawings, in which:

fig. 1 is a perspective view showing a suspension system according to the present invention;

FIG. 2 is a bottom view of the suspension system of FIG. 1;

FIG. 3 is a side view of the suspension system of FIG. 1;

fig. 4 and 5 are bottom and top views, respectively, of a portion of a suspension system according to the present invention;

FIG. 6 is a side view of the portion of the suspension system of FIGS. 4 and 5;

fig. 7 and 8 are respective enlarged perspective views of the connections between the elements of the suspension system according to the invention.

Detailed Description

Fig. 1 discloses a suspension system 1 for connecting an axle 2 of a heavy vehicle to a chassis 3 of the heavy vehicle. As known per se, the chassis 3 comprises a pair of

side members

4, 5, said pair of

side members

4, 5 extending along a longitudinal axis a of the vehicle and being laterally spaced apart.

It should be noted that the suspension system 1 may be provided for a work vehicle including a front axle (not shown) and a single rear axle 2 (see fig. 4, 5 and 6) or two rear axles 2 (fig. 1, 2, 3).

In the case where there are two rear axles 2, the second rear axle 2 is placed in a forward position along the axis a with respect to the first rear axle 2.

Obviously, each rear axle between the first rear axle 2 and the second rear axle 2 may be provided as a support axle (tag axle) 2″ or an electric drive axle 2', and in particular, at least one of the two rear axles 2 may be provided as an electric drive axle 2'.

The electric drive axle 2 'is provided with an electric motor powered by at least one battery module (not shown) to provide torque to the wheels carried by the electric drive axle 2' or to receive electric energy generated by the electric motor when the vehicle is braking. Due to the presence of such a motor, the electric drive axle 2' has a greater extension both forward and backward with respect to the standard axle 2″ in the space comprised laterally along the axis a between the

side members

4, 5.

Thus, the first and second suspension systems 1 are provided between the chassis 3 and the first rear axle 2 and between the chassis 3 and the second rear axle 2, respectively.

Because the second suspension system is identical to the first suspension system, only the first suspension system 1 is referenced, the first suspension system 1 comprising a left side portion 1 "and a right side portion 1'. Because the left 1 "and right 1 'sides are symmetrically identical with respect to the longitudinal axis a, only the right 1' side will be described for the sake of brevity.

Referring to fig. 2 and 6, the suspension system 1 includes a metal beam 7, i.e., a spring beam, the metal beam 7 including a front terminal portion 7a and a rear terminal portion 7b extending along a longitudinal axis a. As described below, the metal beam 7 is connected to the axle 2 in an intermediate portion 7c longitudinally included between the front terminal end portion 7a and the rear terminal end portion 7b.

Each of the front terminal portion 7a and the rear terminal portion 7b is connected to the chassis 3, i.e., to the side member 5, via an air spring such as an air bellows 8 interposed between the chassis 3 and the metal beam 7 in the vertical direction.

In particular, the air bellows 8 comprises an upper portion 8a and a lower portion 8b, the upper portion 8a being configured to be connected to the chassis 3, for example via a bracket 9, and the lower portion 8b being connected to the respective front terminal portion 7a or rear terminal portion 7b, for example via a threaded element. As is known per se, each air bellows 8 comprises an air-bag 8c, which air-bag 8c is carried between the upper and

lower portions

8a, 8b and is configured to contain air under pressure to dampen such relative movement between the upper and

lower portions

8a, 8 b.

The metal beam 7 is also connected to the chassis 3, i.e. to the side members 5, via dampers 11 interposed therebetween in the above-mentioned vertical direction. In particular, the damper 11 is substantially vertical with respect to the side member 5/ground.

Preferably, the damper 11 is a hydraulic damper, i.e. a hydraulic cylinder, comprising a housing 11a carried by the side member 5 and a stem 11b connected to the metal beam 7. As is known per se, the stem 11b is configured to move inside the housing 11a against the action of the fluid contained in the housing 11a to dampen the relative movement between the side member 5 and the metal beam 7.

The stem 11b is connected to the metal beam 7 in a portion comprised between the intermediate portion 7c and one of the front or

rear terminal portions

7a, 7b, as illustrated in the following description.

In particular, the stem 11B is connected to the metal beam 7 via a hinged connection 12, the hinged connection 12 being configured to allow the terminal portion of the stem 11B to rotate about an axis parallel to a transversal axis B, which is the longitudinal axis of the axle 2. The housing 11a is instead connected to the side member 5 via a hinged connection 13, the hinged connection 13 being configured to allow the terminal portion of the housing 11a to rotate about an axis parallel to the longitudinal axis a.

The metal beams 7 are connected to the respective axle shafts 2 via connection assemblies 15, the connection assemblies 15 preferably comprising at least a plate 16, which plate 16 is vertically interposed between the axle shafts 2 and the intermediate portion 7c of the metal beams 7.

The plate 16 defines: a top portion configured to be in contact-fit with an outer surface of the axle 2; and a lower portion configured to be in contact-fit with an outer surface of the metal beam 7.

The connection assembly 15 further comprises a retaining device 17, the retaining device 17 being configured to apply a compressive force between the axle 2, the plate 16 and the metal beam 7 in order to maintain the axle 2, the plate 16 and the metal beam 7 connected together by friction.

In particular, the holding means 17 may comprise two U-shaped brackets 18, the U-shaped brackets 18 being provided with: a threaded terminal end configured to pass through the intermediate portion 7c of the metal beam 7; and threaded elements configured to cooperate with the threaded terminal ends to apply a compressive force between the elements.

The suspension system 1 further comprises a transverse holding element 20, which transverse holding element 20 is configured to support transverse movements acting between the axle 2 and the chassis 3 but to allow vertical movements between these elements.

In particular, the transverse holding element 20 comprises a V-shaped bar 21, which V-shaped bar 21 is provided with a first arm portion 21 'and a second arm portion 21", which first arm portion 21' and second arm portion 21" are provided with a first portion and a second portion, respectively. The first portions are stably connected together and the second portions are spaced apart in the lateral direction from the first portion connection.

Thus, the first arm portion 21' and the second arm portion 21 "are inclined in a horizontal plane with respect to the longitudinal axis such that each of the second portion of the first arm portion and the second portion of the second arm portion is closer to the

respective side member

4, 5. In more detail, the first arm portion 21' and the second arm portion 21″ are symmetrical with respect to the longitudinal axis a.

Advantageously, the first arm portion 21' and the second arm portion 21 "are realized as one piece. The first part of the first arm portion and the first part of the second arm portion are connected to the axle 2 via an articulated connection 22, the articulated connection 22 allowing such first part to rotate about an axis parallel to the transverse axis B. More preferably, the first portion is connected in its upper portion to the axle 2, more preferably via a flange 23 carried by the axle 2 to the axle 2.

The second part of the first arm 21' and the second part of the second arm 21 "are connected to the chassis 3 by means of respective articulated connections 24. In the disclosed embodiment, the hinged connection 24 is realized by a flange element 25, the flange element 25 being carried in such a way as to be suspended from the

respective side member

4, 5. Such flange members 25 are fixed to the

respective side members

4, 5 via fixing elements such as threaded elements.

The suspension system 1 further comprises a stop device 27, which stop device 27 is configured to avoid excessive vertical movement of the axle 2 relative to the chassis 3. In particular, such stop means 27 comprise a flange 28, which flange 28 is fixedly carried by the chassis 3, for example by an intermediate element (not shown) carried by the

side members

4, 5, and which flange 28 is configured to cooperate in contact with the outer surface of the axle 2 when the movement of the axle 2 exceeds a predetermined height.

Advantageously, the suspension system 1 comprises a pair of stop means 27, said pair of stop means 27 being housed in the space laterally comprised by the

side members

4, 5 and being symmetrically disposed with respect to the longitudinal axis a. Preferably, the flange 28 may be provided with a rubber bumper to avoid direct metal-to-metal contact between the axle 2 and the flange 28.

The suspension system 1 further comprises a longitudinal retaining element 30, which longitudinal retaining element 30 is configured to support a longitudinal movement acting between the axle 2 and the chassis 3 but to allow a vertical movement between the axle 2 and the chassis 3.

In particular, the longitudinal holding element 30 comprises a bar 31, which bar 31 connects the axle 2 to the chassis 3 via the metal beam 7. In particular, the bar 31 connects the axle 2 to a front hanger 32 fixedly carried by the

side members

4, 5.

In more detail, the rod 31 comprises, along the axis a, a first terminal portion 31a and a second terminal portion 31b, and an intermediate portion 31c comprised between the first terminal portion 31a and the second terminal portion 31 b.

The first terminal portion 31a is connected to the front hanger 32 via a hinge 33, and the second terminal portion 31b is connected to the metal beam 7 via another hinge 33. The two hinges 33 are configured to allow movement about an axis parallel to the transverse axis B of the respective terminal portions 31a, 31B. It should be noted (see fig. 2) that the bar 31 is placed completely laterally outside with respect to the space comprised by the

side members

4, 5.

The front hanger 32 comprises an upper portion 32 'and a lower portion 32", the upper portion 32' being configured to allow the front hanger 32 to be fixed to the

respective side member

4, 5 and the lower portion 32" being configured to allow the bar 31 to be connected to the

respective side member

4, 5.

The upper portion 32 'defines a plurality of apertures 34, the plurality of apertures 34 being configured to allow the front hanger 32 to be secured to the

side members

4, 5, and the upper portion 32' having a greater longitudinal extent relative to the lower portion 32 ". In other words, the intermediate portion 32 '"connecting the upper portion 32' and the lower portion 32" has a tapered cross section along the longitudinal axis a.

Preferably, the hinge 33 between the bar 31 and the lower portion 32 "of the front hanger 32 is implemented between a pair of terminal legs extending from the lower portion 32" in spaced apart relation, thereby defining a space for receiving the bar 31 and providing support for the hinge 33.

The suspension system 1 further comprises a stabilizer bar 35, which stabilizer bar 35 is configured to dampen a possible torque acting between the axle 2 and the chassis 3.

The stabilizer bar 35 basically includes a generally straight portion 35' (as best shown in fig. 4) and a pair of terminal portions 35". The terminal portion 35 "is connected to the straight portion 35 'via a corresponding curved portion 35'".

The stabilizer bar 35 is placed below the axle 2 and the metal beam 7. Advantageously, the straight portion 35' is carried by the metal beam 7 and the terminal portion is carried by the front cradle 32.

Furthermore, the terminal portions 35 "extend substantially perpendicularly with respect to the straight portions 35', i.e. along the longitudinal axis a, and the terminal portions 35" are each placed on the same side as the straight portions 35'.

The stabilizer bar 35 thus defines a substantially U-shaped path in a horizontal plane, wherein a straight portion 35' is placed between the air bellows 8 and the respective axle 2.

The curved portion 35 '"is positioned externally with respect to the side members 4, 5 (see fig. 2) such that the curved portion 35'" can be turned without interfering with the electric axle 2 "or any other element attached to the

side members

4, 5, such as a battery module.

In more detail, the straight portion 35' is carried by the metal beam 7 via the support means 36. In particular, the support means 36 comprise a first half 36' and a second half 36", the first half 36' being realized fixedly carried by an intermediate portion of the metal beam 7, preferably in one piece, the second half 36" being optionally fixable to the first half 36' to allow the mounting and dismounting of the stabilizer bar 35.

More preferably, both the first half 36' and the second half 36 "are implemented in a metallic material. The support means 36 may comprise two half-shells (not shown in detail) realized in a polymeric material, such as rubber, which are fixed to the respective half-shells 36', 36 "by fixing these respective half-shells 36', 36" together.

In particular, the support means 36 are two devices located at the end of the straight portion 35', i.e. in the vicinity of the curved portion 35", and configured to allow rotation of the stabilizer bar 35 about an axis parallel to the transversal axis B.

The terminal portions 35″ are each connected to the chassis 3 via a connection assembly 38, the connection assembly 38 being configured to allow a movable connection, in particular a rotational movement about an axis parallel to the transverse axis B.

In more detail, the connection assembly 38 comprises a connection element 40, which connection element 40 is provided with a lower end connected to the terminal portion via a hinge 39 and an upper end connected to the chassis 3 via another hinge 39. The hinges 39 are configured to allow rotation about an axis parallel to the transverse axis B.

Preferably, a hinge 39 between the upper end of the connecting element 40 and the chassis 3 is realized between such upper end and the front cradle 32. In more detail, the front hanger 32 defines a support portion 41, which support portion 41 extends in a cantilever manner in the space comprised between the

side members

4, 5.

In particular, the support portion 41 is a flange that extends from the middle portion 32 '"of the front hanger 32 to near the upper portion 32'. Preferably, the support portion 41 is realized in one piece with the front hanger 32, and the connecting element may be detachably mounted to the front hanger 32.

Preferably, the connecting element 40 comprises a pair of arms 40', 40", said pair of arms 40', 40" being laterally placed with respect to the terminal portion 35", thus spaced apart along the transverse direction, and hinged to the hinge 39 at respective terminal ends.

In the double rear axle configuration described, the front hanger 32 is common and allows for the connection of the longitudinal rods 31 and the connection of the stabilizer bar 35 of the two suspension systems 1.

Furthermore, in the two axle 2 configuration, two other possibilities are conceivable, wherein the first rear axle 2 is a drive axle and the second rear axle 2 is a support axle, as shown in fig. 1, and wherein both the first rear axle 2 and the second rear axle 2 are drive axles, as shown in fig. 2 and 3.

The difference between the two embodiments is the position of the damper 11 and the position of the opening of the U-shaped stabilizer bar 35.

In fact, in the configuration of fig. 1, the dampers 11 are all placed in the rear position with respect to the respective axle shafts 2, and the U-shaped stabilizer bars 35 are all open toward the front portion of the vehicle, i.e., the U-shaped stabilizer bars 35 have the same arrangement. In this configuration, the central common front cradle 32 supports a single stabilizer bar 35, while the other stabilizer bar is directly connected to the portion fixedly carried by the

side elements

3, 4.

Alternatively, in the configuration of fig. 2, the damper 11 is placed externally with respect to the respective axle 2, i.e. in a rear position with respect to the first rear axle and in a front position with respect to the second rear axle along the axis a. In this configuration, the stabilizer bar 35 is positioned such that the stabilizer bar is open in opposite directions, i.e. the stabilizer bar 35 is symmetrically opposite with respect to the transverse axis B. In other words, the openings of the U-shaped cross section of the stabilizer bar face each other. In this configuration, the central common front hanger 32 supports two stabilizer bars 35.

The operation of the suspension system 1 described above is as follows.

During movement of the vehicle, at least one axle 2 follows the irregularities of the road and is movable relative to the chassis 3 of the vehicle. In particular, at least a portion of the motive torque is applied to the vehicle via the electric axle 2'.

These movements are dampened by the suspension system 1, in particular:

the vertical movement is dampened by the damper 11 and the air spring 8. Excessive vertical movement is stopped by the stop means 27;

lateral and longitudinal movements are compensated by the V-bar 21 and the longitudinal bar 31; and

torque movement is compensated by the stabilizer bar 35.

In view of the foregoing, the advantages of the suspension system described above according to the present invention are apparent.

The proposed suspension system 1, in particular the position of the stabilizer bar 35, allows to mount the suspension 1 also in the case of the electric axle 2", while maintaining good mechanical properties.

Furthermore, the proposed suspension system 1 is particularly compact. Furthermore, the presence of the connection assembly 38 allows the stabilizer bar 35 to be connected to the generally standard front hanger 32.

The special arrangement of the stabilizer bar 35 between the front hanger 32 and the metal beam 7 allows the use of a standard one-piece stabilizer bar 35.

Similarly, the bar 31 and the V-bar 21 are standard elements and the support/hinge is of standard type. Thus, the suspension system 1 is particularly inexpensive.

In addition, the support 36 allows for easy installation of the stabilizer bar 35 and provides good dampening during rotation of the stabilizer bar 35.

As illustrated, the proposed suspension system 1 may be used for different vehicle configurations, i.e. single drive-drive or drive-support or support-drive configuration, dual drive-drive or drive-support or support-drive configuration. Thus, the proposed suspension system allows economies of scale, as the suspension system can be used for different vehicle configurations.

It is obvious that modifications can be made to the suspension system described without going beyond the scope of protection defined by the claims.

For example, the position and shape of the presence of the elements of the suspension 1 may vary within the limits of the appended claims.

Further, the suspension system 1 may be provided for the following front or rear axles: the front or rear axles are configured as drive or support axles or as standard and electric axles.

The securing means, hinges and connectors shown and described may be varied and replaced by equivalent means.

Claims

1. A suspension system (1) for a heavy vehicle, the suspension system (1) being configured to connect an axle (2) of the heavy vehicle to a chassis (3), the axle (2) extending along a transverse axis (B) with respect to a longitudinal axis (a) of the vehicle, the suspension system comprising:

-a metal beam (7), the metal beam (7) comprising a front terminal portion (7 a) and a rear terminal portion (7 b) along the longitudinal axis (a), and an intermediate portion (7 c) comprised between the front terminal portion (7 a) and the rear terminal portion (7 b);

-a pair of air springs (8), said pair of air springs (8) being operatively interposed between said front terminal portion (7 a) and said rear terminal portion (7 b) and said chassis (3);

-a damper (11), said damper (11) being operatively interposed between said intermediate portion (7 c) and said chassis (3);

-a longitudinal holding element (30), said longitudinal holding element (30) being operatively interposed between said metal beam (7) and a front cradle (32), said front cradle (32) being fixedly carried by said chassis (3);

-a transverse retaining element (20), said transverse retaining element (20) being operatively interposed between said axle (2) and said chassis (3); and

-a stabilizer bar (35), said stabilizer bar (35) being operatively interposed between said metal beam (7) and said chassis (3),

wherein the stabilizer bar (35) is placed under the axle (2) and the metal beam (7), and

wherein the stabilizer bar (35) comprises a straight portion (35 ') and a pair of terminal portions (35 '), the straight portion (35 ') being connected to the metal beam (7), the pair of terminal portions (35 ') extending from the straight portion (35 ') and being connected to the front hanger (32),

wherein said straight portion 35' is supported by said metal beam (7) via support means (36), and wherein both said terminal portions (35 ") are each supported in a freely rotatable manner by said front cradle (32) via a connection assembly (38).

2. Suspension system according to claim 1, wherein the support means (36) comprise: -a first half (36 '), said first half (36') being carried by said metal beam (7); and a second half (36 '), the second half (36 ') being configured to be connected to the first half (36 ') to house the straight portion (35 ') so as to allow rotation of the straight portion (35 ') about an axis parallel to the transversal axis (B).

3. Suspension according to claim 2, wherein the support (36) comprises a polymeric element interposed between the first half (36 ') and the second half (36 ") and the straight portion (35').

4. A suspension system according to claims 1-3, wherein the connection assembly (38) comprises a connection element (40), which connection element (40) is provided with opposite ends hinged to the terminal portions (35 ") of the front suspension bracket (32) and the stabilizer bar (35), respectively, via hinges (39).

5. Suspension system according to claims 1 to 4, wherein the terminal portion (35 ") is connected to the straight portion (35 ') via a curved portion (35'").

6. Suspension system according to any of the preceding claims, wherein the air spring (8) comprises an air bellows provided with upper and lower portions fixed to the chassis (3) and the metal beam (7), respectively.

7. Suspension system according to any of the preceding claims, wherein the damper (11) comprises a hydraulic cylinder hinged with its ends to the chassis (3) and to the metal beam (7) via respective hinges (12, 13).

8. Suspension system according to any of the preceding claims, wherein the intermediate portion (7 c) is connected to the axle (2) via a connection assembly (15), the connection assembly (15) comprising a plate (16) and a retaining means (17), the plate (16) being vertically interposed between the axle (2) and the metal beam (7), the retaining means (17) being configured to provide a compressive force between the axle (2), the plate (16) and the metal beam (7).

9. Suspension system according to any one of the preceding claims, comprising a stop device (27), said stop device (27) being carried by the chassis (3) and configured to limit the vertical movement of the axle (2).

10. Suspension system according to any of the preceding claims, wherein the longitudinal holding element (30) comprises a longitudinal bar (31), the longitudinal bar (31) being hinged between the metal beam (7) and the front hanger (32) at its end.

11. Suspension system according to any one of the preceding claims, wherein the transverse holding element (20) comprises a V-shaped bar (21), the V-shaped bar (21) comprising a first arm (21 ') and a second arm (21 "), the first arm (21') and the second arm (21") comprising: -a first end connected together and hinged to the chassis (3); and second ends each hinged on top of the axle (2), the hinges allowing movement of the respective ends about an axis parallel to the transverse axis (B).

12. Suspension system according to claim 11, wherein the second end of the first arm (21') and the second end of the second arm (21 ") are hinged to a flange (25) carried by the chassis (3).

13. Suspension system according to claim 7, wherein the damper (11) is substantially vertical.

14. A vehicle comprising a rear electric drive axle (2) and a suspension system (1) according to any one of the preceding claims for the rear electric drive axle (2).

15. A vehicle comprising a first rear axle (2 ') and a second rear axle (2 "), the vehicle comprising a first suspension system (1 ') for the first rear axle (2 ') and a second suspension system (1") for the second rear axle, the vehicle comprising a suspension (32) common to the first suspension system (1 ') and the second suspension system (1 "), at least one of the first rear axle (2 ') and the second rear axle (2") being an electrically driven axle.