WO1999030914A1

WO1999030914A1 - Guiding device for a rigid axle in a motor vehicle

Info

Publication number: WO1999030914A1
Application number: PCT/EP1998/007694
Authority: WO
Inventors: Roland Herrmann; Wolfgang Pedrotti
Original assignee: Daimlerchrysler Ag
Priority date: 1997-12-17
Filing date: 1998-11-28
Publication date: 1999-06-24
Also published as: EP1040021A1; DE19756059C2; JP2002508272A; DE19756059A1

Abstract

The invention relates to a guiding device for a rigid axle in a motor vehicle, comprising at least three longitudinal struts (11, 12, 42, 43), whereby two longitudinal wheel-guiding struts (11, 12) which are located on the same plane (10) and structurally coupled between coupling points (33, 34) when they guide the rigid axle by means of a multi-axle joint (31, 32). The longitudinal wheel-guiding struts are coupled between the coupling points by means of a coupling joint (35). The inventive guiding device enables powerful longitudinal and transversal forces to be transmitted to the body of the vehicle, providing good off-road mobility and a compact design.

Description

Guide device for a motor vehicle rigid axle

The invention relates to a guide device for a motor vehicle rigid axle with at least three trailing arms, wherein two wheel-guiding trailing arms of the same link plane are coupled between their articulation points on the body side, while they each guide the rigid axle via a multi-axis joint.

Such a guide device is known from DE-OS 25 05 124. The triangular link coupling axle shown has two parallel, rigid axle-carrying trailing arms which are coupled on the body side between the articulation points there by means of a continuous cross member. The trailing arms and the cross member form a U-shaped component that has a torsionally soft constriction in the central area. The component also has the function of a U stabilizer. This handlebar combination has the advantage that it is articulated only at two points on the vehicle body in addition to a support strut which prevents the axle body from rotating.

This construction is only suitable for relatively light, off-road vehicles. In the event of large lateral forces and / or a larger inclined position of the rigid axle due to the spring deflection, the cross member bends at its narrow point under plastic component deformation. The present invention is therefore based on the problem of creating a guide device for a motor vehicle rigid axle which, independent of a stabilizer and / or a support strut preventing the rotation of the axle body, with good off-road mobility and small structural dimensions, has large longitudinal and transverse forces in only two articulation points on the vehicle body or frame can transmit.

The problem is solved with the features of the main claim. The wheel-guiding trailing arms of the handlebar level are coupled between the articulation points via a coupling joint.

The coupling joint lies, for example, centrally between the articulation points on the body side. It is designed as a ball or universal joint to absorb large forces with at least four degrees of freedom. A translational degree of freedom of the coupling joint, which allows the handlebars to be displaced vertically relative to one another in the millimeter range, prevents the handlebars from being twisted or twisted.

Further details of the invention result from the subclaims not cited and the following description of a schematically represented embodiment:

Figure 1: wishbone-guided rigid axle;

Figure 2: Axle joint between a wishbone and the rigid axle;

Figure 3: Coupling point of the wishbones. Figure 1 shows schematically a steerable rigid axle. Axle guidance is provided by four trailing arms (11, 12 and 42, 43) arranged in two levels (10, 40), which connect the rigid axle body (2) to the vehicle body (5). The rigid axle body (2) is supported on the vehicle body (5) by means of air bellows (3). Wheel-bearing steering knuckles (6) are arranged at its free ends. The latter are coupled to one another, for example, via the tie rod levers (7) and a tie rod (8).

In a e.g. The trailing arms (11) and (12) are located approximately horizontally (10), which lies in Figure 1 below the axis center line (9). Each trailing arm (11, 12) is essentially a triangular component that carries a joint (31-35) in each corner. The trailing arms (11, 12) are preferably made of light metal. This reduces the unsprung mass and thus improves driving dynamics.

The individual handlebar can e.g. a framework, a sheet metal construction or a combination thereof. In the illustrated embodiment, each handlebar (11, 12) includes three - each forming a flat triangle - struts (13-15, 16-17). According to Figures 2 and 3, the struts (13-15, 16-17) each have a rectangular profile as an example. Alternatively, e.g. hollow tube profiles or profiles with a T, H or V cross section can also be used.

Short cantilever arms (21) are attached to the rigid axle body (2), at the ends of which the articulation points for the individual trailing arms are located. The centers of the joints are usually below or above and in front of or behind the center line of the rigid axis. The elastic joints (31, 32) lying below the center line in FIG. 1 have, for example, transverse pivot axes (49), cf. Figure 2. They exist - like the joints (33) and (34)

- From a joint ball (23) bearing

Hinge pin (22). The latter is attached via a side surface to two cantilever arms (21) projecting from the rigid axle body (2). The joint ball (23) is from one to the

Brace (16) or (17) arranged hinge eye (24).

In the space between the inner contour of the

A jointed-in rubber element (25) sits, for example, in the joint eye (24) and the joint ball (23). The

Rubber element (25) around the center line (49)

Swivel angle of ± 15 ° too. Furthermore, it allows swivel angles of several degrees about its vertical and transverse axes, the latter being parallel to the longitudinal axis of the vehicle, the maximum swivel angle about the transverse axis also being able to be up to 30 °. An elastic transverse offset along the center line (49) is also possible in the tenth of a millimeter range. The joints (31-34) are primary

Swivel joints.

The hinge pins (22) of the joints (33) and (34) are attached to the vehicle body (5).

The trailing arms (11, 12) overlap in the central area between the articulation points (33) and (34). The struts (15) and (18) are aligned here. The strut (15) ends in the center of the vehicle with an articulated eye (29), while the strut (18) ends there in a fork head (27). The joint eye (29) lined with an elastic material and the fork head (27) are coupled via a joint bolt (26) provided with a joint ball (28). The coupling joint (35) thus formed largely corresponds to the joints (31-34) in terms of its structure. However, its center line is aligned approximately parallel to the vertical axis of the vehicle and allows an elastically resettable stroke of approximately ± 1 mm along the center line. In Figure 1, a U-stabilizer (41) is shown schematically above the lower trailing arms (11, 12). It lies in an upper link plane (40) which is approximately parallel to the plane (10). The U stabilizer consists of two trailing arms (42) and (43), which are connected via a transverse bar (44) or a comparable component. The trailing arms (42, 43) are mounted on the axle side, for example via ball joints (36, 37) on the rigid axle body (2), while they are supported on the body side in swivel joints (38, 39). The cantilever arms (21) which support the ball joints (36, 37) are generally longer than the cantilever arms which bear the joints (31, 32) and are directed downward.

The trailing arms (42, 43) are preferably designed as approximately flat, torsionally soft plates, the vertical dimension of which is significantly greater than the transverse dimension. This design means that they are stiff in the longitudinal direction of the vehicle and flexible in the transverse direction of the vehicle.

Depending on the design of the rigid axle, the handlebar planes (10) and (40) can also be interchanged, so that, for example, the stabilizer (41) lies below the trailing arms (11, 12).

The lower trailing arms (11, 12) guiding the rigid axle transmit the longitudinal forces from the rigid axle body (2) to the vehicle body (5) or the vehicle frame via the struts (13) and (16). The lateral forces acting on the rigid axle are introduced into the struts (14) and (17) as opposing supporting forces in the central coupling joint (35) and are supported as reaction forces via the struts (15) and (18) on the vehicle body (5).

When the wheels (1) rebound and rebound on the same side, the trailing arms (11, 12) swing in the same direction next to each other back and forth. None occur at the coupling joint (35)

Relative movements between the trailing arms (11, 12).

If the wheels (1) compress each other, the trailing arms (11, 12) twist due to the inclined position of the rigid axle beam. The trailing arm of the rebounding axle side swings down and the longitudinal member of the rebounding side upwards. As a result, in the coupling joint (35), the joint eye (29) and the fork head (27) rotate in the transverse direction of the vehicle. At the same time, the shortest distance between the coupling joint (35) increases compared to a connecting line between the joint parts (31) and (32), as a result of which the struts (15) and (18) enclose an obtuse angle. Thus, tensile forces act on the coupling joint (35) in the transverse direction of the vehicle. In addition, since the axis-side joints (31, 32) are primarily axis-parallel swivel joints, they are pivoted slightly around the connecting line (31, 33) or (32, 34) when the rigid axle body (2) is inclined. Consequently, in the coupling joint (35), the joint eye (29) and the fork head (27) are displaced relative to one another within the framework of the elastic joint compliance.

Since the center of gravity of the trailing arm (11, 12) is not on the connecting line between the joints (31, 33) or (32, 34), but is offset towards the center of the axle, there is a risk that the Swing the trailing arms (11, 12) up and down around the connecting lines (31, 33) or (32, 34) with a small amplitude. To dampen this vibration behavior, the fork head (27) or the joint eye (29) can be supported in the z direction on the vehicle body. For this purpose, the fork carriage, for example, is attached to a hinge part (51) via a rod, cf. Figure 1, articulated. The fork head (27) can just as well be gripped elastically on its upper and lower sides, the gripping being fastened to the vehicle body. Alternatively, the trailing arms (11, 12) can be braced against each other. For this purpose, individual disc springs, stack of disc springs or disc spring assemblies can be installed between the fork head (27) and the joint eye (29). The springs hold the trailing arms (11, 12) in one plane due to the bracing. A leaf spring or leaf spring combination guided along the struts (15) and (18) has a comparable effect.

Reference list

Wheels rigid axle body air springs, bellows

Vehicle body steering knuckle Tie rod arm Tie rods Axle center line

lower link level, 12 trailing links, 14, 15 struts from (11), 17, 18 struts from (12)

Cantilevered hinge pin Hinge ball on (22) Hinge eye on (16, 17) Rubber element

Swivel pin clevis on (17, 18) Swivel ball on (26) Swivel eye on (15, 17)

, 32 joints, on the axle side, 34 articulation points on the vehicle body coupling joint, 37 stabilizer articulations, on the axle side, 39 stabilizer articulation points on (5) 40 upper handlebar level

41 U stabilizer

42, 43 trailing arms

44 crossbar

49 swivel axis of (31-43; 36-39)

51 Central articulation point at (5)

Claims

claims

1. Guide device for a motor vehicle rigid axle with at least three trailing arms (11, 12, 42, 43), two wheel-guiding trailing arms (11, 12) being the same

Handlebar level (10) between their body side

Articulation points (33, 34) are coupled while they are

Rigid axles each lead via a multi-axis joint (31, ₃ 2), characterized in that the longitudinal links (11, 12) of the link level (10) are coupled between the articulation points (33) and (34) via a coupling joint (35).

2. Guide device according to claim 1, characterized in that the coupling joint (35) has three rotary and one translational degree of freedom.

3. Guide device according to claim 2, characterized in that the translational degree of freedom of the coupling joint (35) is oriented in the z direction.

4. Guide device according to claim 1, characterized in that each link (11, 12) of the link level (10) from the axle joint (31, 32), from the articulation point (33, 34) and from the coupling joint (35) partially spanned triangle fills in, handlebar profiles are arranged at least in the vicinity of the triangle legs.

5. Guide device according to claim 1, characterized in that the material of the trailing arm (11, 12) is a light metal alloy.

6. Guide device according to claim 1, characterized in that the coupling joint (35) or one of the trailing arms (11, 12) of the steering plane (10) in the region of the coupling joints (35) in the z direction on the vehicle body (5) is mounted.

7. Guide device according to claim 1, characterized in that two trailing arms (42, 43) are arranged in a second link plane (40).

8. Guide device according to claim 7, characterized in that the trailing arms (42, 43) are coupled via a cross bar (44) and together form a U-stabilizer (41).

9. Guide device according to claim 7, characterized in that the U-stabilizer (41) is arranged above, in front of or behind the rigid axle body (2).