DE10336800B4 - Twist-beam axle for a motor vehicle - Google Patents

Abstract

Torsion beam axle for a motor vehicle, comprising: - two substantially longitudinally extending axle guide (1) which are each pivotally coupled with one end to the vehicle body, - a Torsionsprofil (8), which is open at its bottom and the two axle guide (1 ) in the transverse direction torsionally elastic, but rigidly connected to each other, and which has a modified V-shape, wherein in a first portion (14) of a apex region (13) substantially straight running away legs (11, 12) in each case to form a bend ( 15, 16) are bent inwards and continue steeper in a subsequent, second section (17), and - two inner supports (10) which are respectively arranged in the rear gusset between the torsion profile (8) and a wishbone (1) characterized in that the inner supports (10) are bow-shaped with two superimposed flanges (21, 22) and with each flange (21, 22) on the first section (14) are supported, and on their side facing away from the respective axle link (1) side having a transversely extending slot (23).

Description

The invention relates to a torsion beam axle for a motor vehicle according to the preamble of patent claim 1.

Such twist beam axle are alike DE 198 46 400 A1 and DE 199 10 575 A1 known.

Twist-beam axles, which connect the rear wheels of a motor vehicle with its structure, have long been known from the prior art. Under an externally acting side force, the outside wheel tends to go in the forefront. However, this is undesirable and is compensated for by suitable elastokinematic track and camber changes in mutual compression. A major factor in this case is the flexibility of the torsion profile connecting the wishbones in the vehicle transverse direction. At the same time, the torsion-beam axle must be as far as possible from the side, lintel and pre-track stiffness. For this reason, a torsion profile with high bending stiffness is sought. The problem here is in particular the connection area of the torsion profile on the wishbones. Although rigid inner supports between the wishbones and the torsion profile favor a stable connection, however, under torsion can lead to an inhomogeneous deformation course along the Torsionsprofils. Thus, especially at the end of the inner supports a strong voltage gradient occur.

The DE 24 30 048 C3 discloses a torsion beam axle of the type mentioned, in which the downwardly open torsion profile is formed in cross-section V-shaped. The inner supports are simple gusset plates which are welded to the top of the Torsionsprofils this.

A similar construction is still from the DE 27 40 948 C2 Known in the gusset plates serve to auszusteifen the transition region between a V-shaped torsion profile and each one axle link.

The use of gusset plates in conjunction with a downwardly open, U-shaped torsion profile is in the DE 198 08 172 A1 disclosed. The chart plates are welded to the stub axles and the torsion profile. To reduce the transmitted via the weld tension peaks notches are provided on the gusset plates.

Also the DE 297 20 207 U1 shows a torsion beam axle of the type mentioned, in which a V-shaped torsion is stiffened in the transition region to the shaft elements by node elements.

Against this background, the object underlying the invention is to increase the component rigidity in a torsion beam axle of the type mentioned in order to improve the driving dynamics of the vehicle.

This object is achieved by a torsion beam axle with the features of claim 1.

As in the prior art, the torsion profile is open at the bottom, so that the shear center is as high as possible. In contrast to conventional solutions, however, the profile according to the invention has at least one additional bend per leg, which has a stiffening effect with regard to the lateral, lintel and track stiffness. As a result of this surprisingly simple modification of the cross-sectional geometry of the torsion profile, very high rigidity values can be achieved in comparison to previously known, comparable twist-beam steering axles. With a corresponding wall thickness of the Torsionsprofils can even be dispensed with an otherwise additionally existing stabilizer.

The purpose of the inner supports is to introduce forces that occur under side force influence in the torsion profile to relieve the connection area between the torsion and the wishbones.

So that the desired deformation behavior of the torsion profile is not impaired too much, the support of the inner supports takes place at the first portion of the torsion profile of the modified V-shape. The inner supports are bow-shaped with two superimposed flanges and supported with each flange on the first section. This ensures a high stability and durability of the connection between the torsion profile and the respective wishbone.

By forming a slot on the side facing away from the respective wishbone we ensure that the end of the connection between the inner support and the Torsionsprofil is not too stiff, otherwise the warping of the Torsionsprofils would be too much hindered and the connection would not have sufficient durability.

According to the invention thus results in a rigid connection and the lowest possible curvature.

Advantageous embodiments of the invention are the subject of further claims.

According to an advantageous embodiment, the legs can run parallel to each other in the steeper second section.

Preferably, the first section has a greater height with respect to the profile center axis than the second section.

A further stiffening effect results when, according to a further advantageous embodiment, the legs are bent outwards following the second section to form a further bend and form a third section there. Each leg of the V-shape is then modified by two stiffening kinks, so that the overall result is a hat-shaped profile.

Preferably, the legs are bent at the other bend by 80 to 100 degrees outwards.

In an advantageous embodiment, the inner supports are welded into the respective gusset between the Torsionsprofil and a wishbone.

Preferably, the support of the inner supports takes place in the apex region of the modified V-shape. This is favorable for the durability of the connection.

The slot on the inner supports may be formed as a slot. However, the slot may also be open at one end. In order to keep the voltage increase at the closed end of the slot as small as possible, this is rounded in an advantageous embodiment at its pointing to the wishbone end.

In addition, it can be provided that the slot width increases towards the end which faces the axle element. For this purpose, the free ends can be compressed laterally of the slot. As a result, the open end can be arranged in a region of small torsional curvature of the torsion profile.

For the same reason, it is advantageous if the upper edges of the inner supports extend substantially parallel to the upper edge of the Torsionsprofils.

Furthermore, the upper edge of the Torsionsprofils can lie in the connection area to the axle elements at the height of the upper edge of the wishbone.

A possibly required console with a receptacle for a spring can be attached so that it overlaps the relevant inner support. In this case, the console can be at least partially welded to the inner support.

According to a further advantageous embodiment of the invention, the inner supports are each made in one piece from a piece of sheet metal even in the presence of two superimposed flanges. When viewed in the plan view of the torsion beam axis is preferably the shape of a triangle.

The invention will be explained in more detail with reference to an embodiment shown in the drawing. The drawing shows in:

1 a spatial representation of an embodiment of a torsion beam axle according to the invention,

2 a detailed view of the connection region of the torsion profile to a wishbone,

3 a cross-sectional view of the torsion profile, and in

4 a detailed view of an inner support with an opening for stiffening the connection of the torsion profile to the axle.

The exemplary embodiment shows a torsion beam axle for a passenger vehicle, by means of which the rear wheels of the vehicle are supported against its construction.

In the 1 shown twist beam axle comprises per vehicle wheel a wishbone 1 which extends substantially in the vehicle longitudinal direction. Every wishbone 1 has a bearing at its front end 2 for pivotable coupling to the vehicle body. The pivot axes of the bearings 2 Run essentially in the vehicle transverse direction. Each of the bearings 2 is designed as a elastokinematic bearing, for example as a rubber-metal bearing to effect in cooperation with other elastokinematic components suitable track and camber corrections under side force influence and / or mutual compression.

At the axle links 1 there is one wheel carrier each 3 at the front end of a tubular outlet and bent outward end portion 4 of the wheel carrier 3 is attached. At the end section 4 is still an obliquely downward and rearward extending console 5 attached, which is a recording 6 for a strong in the direction of the wishbone 1 inclined vibration damper 7 formed. However, the wishbones 1 be designed differently than in the illustrated embodiment.

In any case, however, the two wishbones 1 in the transverse direction by a transverse strut in the form of a Torsionsprofils 8th connected with each other. This torsion profile 8th is open on its underside and due to its geometry torsionally soft or torsionally elastic, but rigid. As 1 shows is the rectilinear torsion profile 8th with its two axial ends respectively on the inside of the axle guide 1 welded. This is the height of the top edge 9 of the torsion profile 8th at the height of the upper edges of the wishbones 1 ,

To stiffen the connection area is in the rear gusset between the Torsionsprofil 8th and one axle each 1 one inner support each 10 intended. The inner supports 10 are each with the torsion profile 8th and a wishbone 1 connected and cause a stiffening. They are, as in particular by means of 2 can be seen, when viewed in the plan view of the torsion beam axis formed triangular.

With regard to the improvement of the driving dynamics of a vehicle equipped with a torsion beam axle, the component stiffness is increased by the measures explained in more detail below in the construction described here.

This is achieved primarily by the configuration of the cross section of the Torsionsprofils 8th , An optimization of the component stiffness is due to the special design of the inner supports 10 receive. This way, in conjunction with the bearings 2 Nachspureffekte occurring under side force influence can be compensated by a suitable elastokinematic lane and camber change in mutual compression.

The cross section of the torsion profile 8th , which is consistently constant here, is now based on 3 be explained in more detail. In contrast to conventional torsion profiles 8th the profile according to the invention in cross section has a modified V-shape with two legs 11 and 12 on.

The two thighs 11 and 12 run from a vertex area 13 , which at the same time the upper edge 9 of the torsion profile 8th forms substantially straight apart, including a V-angle. This area will also be referred to as the first section below 14 of the torsion profile 8th designated.

The thigh 11 and 12 are at the bottom of the first section 14 each with the formation of a kink 15 respectively. 16 bent inwards, in a subsequent, second section 17 steeper to continue. Preferably, the leg portions of the second section extend 17 parallel or nearly parallel to each other. The extra kinks 15 and 16 act next to the execution as V in the first section 14 as further stiffening in terms of lateral, lintel and track stiffness of the entire axle.

Following the second section 17 are the thighs 11 and 12 under training of a further Knicks 18 respectively. 19 bent over to the outside, to there a third section 20 to build. The leg ends of the third section 20 are at the other creases 18 respectively. 19 bent outwards by 80 to 100 degrees. This results in the cross-sectional view of an approximately hat-shaped profile. Bending the ends of the thighs 11 and 12 outward also acts stiffening, especially around the vehicle's vertical axis.

As 3 shows, the cross section is substantially symmetrical to a profile center axis A. Here, the first section 14 with respect to the profile central axis A a greater height than the second section 17 , The share of the third section 20 in the vertical direction is rather marginal.

By the above-explained geometry of the Torsionsprofils 8th Very high stiffness values can be achieved compared to conventional, comparable twist-beam axles. With a corresponding wall thickness can even be dispensed with an additional stabilizer.

To the possibilities of the torsion profile 8th optimal exploitation, compared to conventional twist beam axles, a stiffening of the connection to the respective wishbone 1 required.

Serve the inner supports 10 in the respective gusset between the torsion profile 8th and a wishbone 1 are welded. In principle, these may be formed as simple nodal plates as in the prior art. However, in order to optimize the stiffness of the torsion beam axis, these are preferably bow-shaped with two superimposed flanges 21 and 22 educated.

The inner supports 10 are each made in one piece from a piece of sheet metal and have the shape of a triangle when viewed in the top view of the beam axis.

Above all, they serve to improve lateral forces in the torsion profile 8th to initiate thereby the connection between the Torsionsprofil 8th and the respective wishbone 1 to relieve. In the connection area are the inner columns 10 due to its two-ply design with two vertically spaced flanges 21 and 22 stiffer than conventional arrangements. Nevertheless, a desired, sufficient warping of the Torsionsprofils 8th and thus to ensure the desired torsional elasticity and softness while avoiding too much transverse torsional stiffness gradient, is the end of the connection between the inner support 10 and the torsion profile 8th soft. If one were to train this also stiff, then too much obstruction of the warping of the torsion profile would result 8th , In addition, the connection would then have no sufficient durability.

The inner supports 10 are therefore each provided at their inwardly directed ends with an opening. Preferably, the opening is in the transition region between the two flanges 21 and 22 arranged. This opening is in the illustrated embodiment, each as a transverse slot 23 formed on the one of the respective axle link 1 opposite end is open. At the opposite end in the direction of the associated wishbone 1 is the slot 23 with the largest possible radius 24 provided in order to keep the Spannungsübererhöhung at the end of the slot as low as possible.

As the 1 and 4 show is the inner support 10 in the area of the open end of the slot 23 compressed, so that the slot width in the direction of the respective wishbone 1 increases. In addition, the inner columns 10 also tapered in their thickness towards their pointing in the direction of the vehicle longitudinal center axis ends. As a result, the lower weld end lies on the lower flange 22 in an area with little deformation of the torsion profile 8th , so that hereby spikes are minimized.

In particular 2 shows are the inner columns 10 with both flanges 21 and 22 at the back first section 14 of the torsion profile 8th welded. The top of the inner supports runs 10 or the upper edge of the upper flange 21 almost parallel to the top edge 9 of the torsion profile 8th because there is the warping of the torsion profile 8th is lowest. In addition, the inner columns stand 10 not down over the torsion profile 8th or the wishbones 1 in front.

The top edge 9 of the torsion profile 8th lies in the connection area to the wishbones 1 at the height of the upper edge of the wishbone 1 , A console 25 with a recording 26 for a spring 27 is in the outward widening area of the wishbone 1 arranged on the inside thereof. The console 25 can thereby at least partially on an inner support 10 be welded.

The above-described embodiment of a torsion beam axle allows compared to conventional twist-beam higher stiffness and led to an improvement of the axle kinematics. This results in an improvement in the driving dynamics of the vehicle. Due to the higher component rigidity, it may be possible to dispense with an additional stabilizer.

However, the invention is not limited to the illustrated embodiment, but includes all embodiments specified in the claims.

LIST OF REFERENCE NUMBERS

1

wishbone

2

camp

3

wheel carrier

4

end

5

console

6

admission

7

vibration

8th

torsion

9

top edge

10

internal support

11

leg

12

leg

13

apex region

14

first section of the torsion profile 8th

15

kink

16

kink

17

second section of the torsion profile 8th

18

another kink

19

another kink

20

third section of the torsion profile 8th

21

(upper) flange

22

(lower) flange

23

slot

24

curve

25

console

26

spring mount

27

feather

A

The center profile line

Claims (15)

Torsion beam axle for a motor vehicle, comprising: - two substantially longitudinally extending wishbones ( 1 ), which are each pivotally coupled to one end of the vehicle body, - a Torsionsprofil ( 8th ), which is open on its underside and the two wishbones ( 1 ) in the transverse direction torsionally elastic, but rigidly connected to each other, and which has a modified V-shape, in which in a first section ( 14 ) from a vertex area ( 13 ) substantially straight running legs ( 11 . 12 ) each with formation of a bend ( 15 . 16 ) are bent inwards and in a subsequent, second section ( 17 ) continue steeper, and - two inner supports ( 10 ), each in the rear gusset between the Torsionsprofil ( 8th ) and a wishbone ( 1 ) are arranged, characterized in that the inner supports ( 10 ) bow-shaped with two superimposed flanges ( 21 . 22 ) and with each flange ( 21 . 22 ) on the first section ( 14 ) are supported, and at their by the respective wishbone ( 1 ) facing away from a transversely extending slot ( 23 ) exhibit. Twist-beam axle according to claim 1, characterized in that the legs ( 11 . 12 ) in the second section ( 20 ) parallel to each other. Twist-beam axle according to claim 1 or 2, characterized in that the legs ( 11 . 12 ) following the second section ( 17 ) with the formation of another bend ( 18 . 19 ) are each bent outward and there a third section ( 20 ) form. Twist-beam axle according to claim 3, characterized in that the limbs ( 11 . 12 ) at the further bend ( 18 . 19 ) are bent outward by 80 to 100 degrees. Twist-beam axle according to one of claims 1 to 4, characterized in that the first section ( 14 ) has a greater height with respect to the profiled central axis (A) than the second section (A) 17 ). Twist-beam axle according to one of claims 1 to 5, characterized in that the inner supports ( 10 ) are welded in the respective gusset. Twist-beam axle according to one of claims 1 to 6, characterized in that the inner supports ( 10 ) are each made in one piece from a piece of sheet metal. Twist-beam axle according to one of claims 1 to 7, characterized in that the inner supports ( 10 ) are triangular when viewed in the plan view of the torsion beam axis. Twist-beam axle according to one of claims 1 to 8, characterized in that the slot ( 23 ) is open at one end. Twist-beam axle according to one of claims 1 to 9, characterized in that the slot ( 23 ) at his to the wishbone ( 1 ) pointing end is rounded. Twist-beam axle according to one of claims 1 to 10, characterized in that the slot width of the slot ( 23 ) to the end leading to the wishbone ( 1 ), increases. Twist-beam axle according to one of claims 1 to 11, characterized in that the upper edges of the inner supports ( 10 ) substantially parallel to the upper edge ( 9 ) of the torsion profile ( 8th ). Twist-beam axle according to one of claims 1 to 12, characterized in that the upper edge ( 9 ) of the torsion profile ( 8th ) in the connection area to the wishbones ( 1 ) at the height of the upper edge of the wishbones ( 1 ) lies. Twist-beam axle according to one of claims 1 to 13, characterized in that a console ( 25 ) with a receptacle for a spring ( 27 ) at least in sections on the inner support ( 10 ) is welded. Motor vehicle with a torsion beam axle according to one of claims 1 to 14.

Images