EP2882601A1

EP2882601A1 - Independent suspension

Info

Publication number: EP2882601A1
Application number: EP13735318.1A
Authority: EP
Inventors: Klaus Gell
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2012-08-13
Filing date: 2013-07-12
Publication date: 2015-06-17
Also published as: CN104582982A; CN104582982B; DE102012214352A1; WO2014026808A1

Abstract

The invention relates to an independent suspension for a commercial vehicle, comprising a steering knuckle, which is arranged on a steering knuckle pin in a rotatable manner about a first rotational axis and which comprises a wheel hub; a steering knuckle carrier, which is connected to the steering knuckle by means of the steering knuckle pin; a vibration damper and a spring element, each of which can be fixed to a fixing element formed on the steering knuckle carrier and to another fixing element of the vehicle body; and at least one upper transverse link and at least one lower transverse link, which are at least indirectly connected to the steering knuckle and to another fixing means of the vehicle body. The upper transverse link is arranged above the steering knuckle carrier in the installed position, and the lower transverse link is arranged below the upper transverse link in the installed position. The invention is characterized in that the upper transverse link is fixed to the steering knuckle pin and is rotatably supported about a second steering knuckle-side rotational axis; the lower transverse link is supported on the steering knuckle carrier in a rotatable manner about a third steering knuckle-side rotational axis of the lower transverse link; and the third steering knuckle-side rotational axis of the lower transverse link is radially spaced from the first rotational axis of the steering knuckle.

Description

independent suspension

The invention relates to an independent suspension for a commercial vehicle.

A generic independent wheel suspension for a motor vehicle with a steering knuckle with a wheel hub, a steering knuckle, an upper wishbone and a lower wishbone is known for example from EP 0 935 537 B1.

Today, high demands are placed on the economical use of commercial vehicles. In particular, an optimal utilization of the loading space, or the interior of a bus, is becoming increasingly important. That is, the independent wheel suspensions for a vehicle must be designed so that the gap between two independent wheel suspensions, which are fixed to both sides of a vehicle to the vehicle body, with as little loss as possible, ideally be fully usable.

The steering knuckle disclosed in EP 0 935 537 B1 is rotatably connected to the steering knuckle carrier with the aid of a steering knuckle pin. The lower wishbone is mounted with a ball joint on the underside of the steering knuckle. Above the lower wishbone, the upper wishbone is fixed to the upper part of the steering knuckle carrier via a pair of tapered roller bearings.

In the embodiment variant described in EP 0 935 537 B1, the control arms protrude very far in the direction of the center of the vehicle, together with the steering knuckle carrier, and thus severely limit the space between two independent wheel suspensions of a vehicle.

A similar independent suspension is disclosed in EP 1 985 474 A2 and in DE 20 2008 017 914 U1. Also there, the wishbone are attached to a steering knuckle, which is connected by means of a kingpin with the steering knuckle. An optimal utilization of the gap between two Independent suspensions is not sought in these documents and can not be guaranteed.

DE 10 2007 047 791 A1 discloses an independent suspension for vehicles, which has upper and lower control arms, which are attached to one end of the kingpin and fixed to each opposite end of the wishbone on the vehicle frame. The steering knuckle is rotatably supported by two bearings on the kingpin.

The use of a stub axle carrier has been omitted, instead a spring carrier was used between the bearing points of the stub axle, which carries a spring-damper module, or instead a vibration damper and an air spring, which on the one hand on the spring carrier and on the other hand on a fastening element of the vehicle frame support and absorb the vertical relative movements of the vehicle frame against the road surface damping.

Since the wishbones are at least indirectly attached to the kingpin, and these are thus arranged closer to the wheel, the distance between the wishbones on each side of the vehicle is significantly larger. This results in a significant space advantage.

The upper and the lower wishbones are mounted so that they allow only a vertical movement of the kingpin The spring carrier is secured between the bearing points of the steering knuckle on the kingpin by means of a press fit. As a result, a rotation of the spring carrier on the kingpin is prevented only by the friction between the surface of the kingpin and thus standing in frictional contact with the inner surface of the spring carrier. Since the kingpin is designed to be cylindrical at the attachment point of the spring carrier and has a constant radius, it may in extreme situations to a rotation of the spring carrier relative to the kingpin, which would lead to an undesirable change in the defined axle geometry. Although this disadvantage can be overcome by further measures, such as an additional cohesive connection of the two components kingpin and spring carrier are prevented, which would cause additional effort and additional costs.

Based on the cited prior art, the present invention has the object to construct a cost-optimized independent suspension for commercial vehicles so that it provides optimum space utilization between mounted on both sides of the vehicle independent suspension, as well as a change in the axle geometry of the independent suspension under extreme loads prevented.

This object is solved by the features of patent claim 1. Further advantageous embodiments of the independent suspension for vehicles according to the invention will become apparent from the dependent claims and the figures.

Accordingly, an independent suspension is proposed for a commercial vehicle comprising a stub axle rotatably mounted on a stub axle about a first axis of rotation with a wheel hub, a stub axle connected to the stub axle by the stub axle, a vibration damper and a spring element each on the one hand on a stub axle carrier Fastening element and on the other hand can be feslegbar to another fastener of the vehicle body, at least one upper control arm, and at least one lower wishbone, wherein the wishbones are at least indirectly connected to the steering knuckle and on the other hand with a further fastening means of the vehicle body, wherein the upper wishbone in the installed position is arranged above the steering knuckle carrier and wherein the lower arm is arranged in the installed position below the upper arm, wherein the upper arm on the Ac is fastened and rotatably mounted about a second axis of rotation of the upper arm, the lower arm being rotatably mounted on the stub axle about a third axis of rotation of the lower arm, and wherein the third axis of rotation of the lower arm is radially of the first arm Rotary axis of the steering knuckle is spaced. Due to the arrangement of the upper control arm directly to the kingpin the distance between the opposite upper wishbones on the vehicle frame can be selected to be correspondingly large.

The stub axle carrier assumes the role of a spring carrier and carries a vibration damper and a spring element, which are supported at one end to the stub axle carrier and at the other end to the vehicle frame. Since the lower arm is fixed on the one hand to the stub axle and the other on the vehicle body, and only a vertical movement of the stub axle relative to the vehicle frame, but no horizontal movement, the stub axle carrier has no possibility to rotate relative to the kingpin, creating a change in the axle geometry is prevented in extreme conditions.

According to a further advantageous embodiment variant, the second axis of rotation of the upper transverse arm of the upper arm cuts the first axis of rotation of the steering knuckle. As a result, the weight of the upper control arm can be introduced directly into the kingpin.

It is advantageous to arrange the vibration damper and the steering knuckle carrier in such a way that the longitudinal extension axis of the vibration damper intersects the third axis of the swivel axis of the lower transverse link. Thus, the vertical movements of the vehicle frame relative to the steering knuckle carrier can be better supported and damped.

In order to stabilize the roll behavior of the vehicle even more, the wishbones, according to a further advantageous embodiment, be arranged such that the third axis of rotation axis of the lower arm, and the second axis of rotation axis of the upper arm is in a space between the stub axle and the spring element are located. According to a further advantageous variant, the stub axle carrier may be configured S-shaped and have, for example, a first extension section, a second extension section and a third extension section, which are interconnected by a first bending section and a second bending section. Thus, the steering knuckle can be installed in accordance with space-saving in the independent suspension and despite the sufficient space for other components, such as a vibration damper and a spring element offer.

The fastening elements, for fastening the vibration damper and / or for fastening a vehicle frame supporting the spring element can be performed directly on the steering knuckle in accordance with further advantageous subclaims.

In order to reduce the weight of the steering knuckle carrier, this may have a section with a recess or with a reduced material thickness.

In order to increase the load capacity of the connection between the stub axle carrier and the stub axle, it is advantageous to design the stub axle carrier such that it has a fork at its end facing the steering knuckle, which fork comprises an upper end section and a lower end section. In this case, the end portions can enter into an engagement formation with the bearings projecting from the surface of the steering knuckle facing away from the wheel hub.

Further details and advantages of the present invention will become apparent from the following description of an embodiment in conjunction with the drawings. In this show:

1 is a perspective view of the independent suspension according to the invention for a commercial vehicle.

Fig. 2 is a partial sectional view of the independent suspension according to the invention shown in FIG. 1; 3 is a perspective view of an alternative steering knuckle carrier;

1 and 2 each show a representation of an independent suspension 1 according to the invention for a commercial vehicle, according to claim 1. The independent suspension 1 shown there comprises a steering knuckle 2 with a wheel hub 3. The steering knuckle 2 is connected by means of a kingpin 4, with a stub axle 5 and is rotatably mounted about a rotation axis A. The kingpin 4 is shown in Fig. 2 in a section and is there even better visible. At one, in Figs. 1 and 2 upper end, the kingpin 4 has a loop-shaped mounting portion 6, with a running therein through the fastening opening 7, which was designed here as a bore. Adjacent thereto, the kingpin 4 has a cylindrical mounting portion 8. In the attachment opening 7 of the kingpin 4, at least one bearing 9 is provided, which has a defined vertical deflection of the attached at this point upper arm 10; 1 1 allows. The bearing 9 to be used may be embodied as a needle bearing, a ball bearing, a sliding bearing or a molecular bearing. The mounting portion 8 of the kingpin 4 has a constant over the entire length of its cross section. In Figs. 1 and 2, an embodiment of the independent suspension according to the invention l is shown, which a total of two upper wishbone 10; 1 1 provides. The two upper wishbones 10; 1 1 each have two also eye-shaped end portions 12; 13, are with an end portion 12; 13 are arranged on one side of the eye-shaped fastening portion 6 of the kingpin 4 and are fixed with a fastening bolt 14 to the mounting portion 6 of the kingpin 4. The upper wishbones 10; 1 1 are thus attached to the kingpin 4 and about a axle-side pivot axis B of the upper arm 10; 1 1 rotatably mounted. The upper wishbones 10; 1 1 are arranged so that the axle leg rotation axis B of the upper arm 10; 1 1, the axis of rotation A of the steering knuckle 2 cuts. The opposite end portion 15; 16 of each upper arm 10; 1 1 is in each case with a bearing 17; 18 equipped, which the attachment of the control arm 10; 1 1 serve at a further, not shown in the figures fastening means of the vehicle body. The steering knuckle 2 shown in FIGS. 1 and 2 is connected at one end to the wheel hub 3. Furthermore, the steering knuckle 2 has an upper bearing point 19 and a lower bearing point 20 in FIGS. 1 and 2, the bearing points 19; 20 at the, the hub 3 opposite side of the steering knuckle 2 are executed and wherein in the bearings 19; 20 breakthroughs 19 '; 20 'are executed, which bearings 21; 22 record to allow a steering movement of the wheel, the bearings 21; 22 each have an opening 21 '; 22 'for receiving the kingpin 4 have. The bearings 19; 20 of the steering knuckle 2 protrude from the surface of the steering knuckle 2 in the, the wheel hub 3 opposite direction. A stub axle 5 is with its achsschenkelseitigem end 23 between the two bearings 19; 20 of the steering knuckle 2, wherein in the designated end 23 of the steering knuckle 5, a continuous mounting hole 24 is executed, which the apertures 19 '; 20 'of the bearings 19; 20 connects with each other. The openings 19 '; 20 'of the bearings 19; 20 and the mounting hole 24 of the steering knuckle 2 are aligned coaxially with each other and each have an equal inner diameter. The kingpin 4 is through the two openings 21 '; 22 'of the bearings 21; 22, which in the bearings 19; 20 of the stub axle 2 are received and performed by the mounting hole 24 of the stub axle 5, which between the designated bearings 19; 20 is positioned. Thus, the assembly consisting of the stub axle 2, the kingpin 4 and the stub axle 5, positively connected to each other.

The outer diameter of the mounting portion 8 of the kingpin 4 usually has a slight excess compared to the inner diameter of the mounting hole 24 of the steering knuckle 5. During assembly, the cross section of the kingpin 4 is reduced by a strong temperature reduction before installation, so that this through the openings 21 ';24; 22 'can be performed and after reaching its end position, as well as under the influence of the ambient temperature, increases the cross section and enters into a clamping connection with the stub axle 5. To contamination of the bearings used in the steering knuckle 2 21; To avoid 22, the kingpin 4 between its mounting portion 6 and its mounting portion 8, a protective cover 25, which can be carried out both integrally with the kingpin 4, as well as a separate component. The open end of the FIGS. 1 and 2 illustrated lower opening 20 of the steering knuckle 2 is closed with a cup-shaped closure element 26.

The substantially S-shaped stub axle carrier 5 illustrated in FIG. 1 has a first extension section 27, a second extension section 29 and a third extension section 31, which are connected to one another by a first bending section 28 and a second bending section 30. The first extension section 27 extends approximately horizontally, starting from the end 23 of the steering knuckle carrier 5 mounted on the knuckle 2 in the direction opposite to the wheel hub 3, ideally parallel, but slightly inclined here, to the road surface not shown in the figures. The first bending section 28 directly adjoins the first extension section 27 and has an upper radius 32 and a lower radius 33, so that the second extension section 29 adjoining the first bending section 28 projects with a significantly greater inclination in the direction of the road surface, compared to FIG first extension portion 27, is aligned. Adjoining the second extension section 29 of the stub axle carrier 5 is the second bending section 30, which likewise has an upper radius 34 and a lower radius 35. The third extension portion 31 adjacent to the second bending portion 30 extends almost parallel to the road surface in the direction opposite to the wheel hub 3. As shown in FIG. 1 and in FIG. 2, a fastening element 36, for fastening a vibration damper 37, is embodied on the second extension section 29 of the steering knuckle carrier 5. Of course, this can also be design and / or requirements due to run at a different point of the Aschschenkelträgers 5.

To reduce the weight, a portion 51 with a recess or at least with a significant reduction in the Material thickness provided. Illustrated in FIGS. 1 and 2 is an example in which the section 51 of reduced material thickness extends over the first extension section 27, the first bending section 28 and the second extension section 29.

According to the embodiment variant shown in FIGS. 1 and 2, an opening 38 is made in the area of the second bending section 30 of the steering knuckle carrier 5, between its upper radius 34 and its lower radius 35, which can receive at least one bearing 39 in order to accommodate the vertical deflection of one There arranged lower arm 40 to ensure. At this point, the illustrated in Figs. 1 and 2 lower arm 40 is fixed to the steering knuckle 5 and is rotatably mounted about a axis of the axle axis of rotation C of the lower arm 40. The axle leg rotation axis C of the lower arm 40, is radially spaced from the axis of rotation (A) of the steering knuckle 2. The vibration damper 37 is arranged so that the longitudinal extension axis S of the vibration damper 37 intersects the axis of the arm axis C of the lower arm 40.

In general, however, it is likewise possible to displace the opening 38 of the lower transverse link 40, as well as the fastening element 41 running on the third extension section 31 of the steering knuckle carrier 5, to fasten a spring element 42 supporting the vehicle frame to a different point of the ashtray carrier 5.

Furthermore, the embodiment variant according to the invention provides in FIGS. 1 and 2 that the axis of rotation of the axis of rotation of the lower transverse link 40 and the axis of rotation of the axle 10 of the upper transverse link 10; 1 1 are arranged in a space between the steering knuckle 2 and the spring element 42.

The lower arm 40 shown in Figures 1 and 2 is designed as a one-piece substantially triangular component, which a plurality of recesses 40 '; 40 "; 40 '". The recesses 40 '; 40 ", 40 '" of the lower arm 40 are designed for the purpose of weight reduction. The outer shape of the recesses 40 '; 40 ", 40 '" is to the outer shape of the lower arm 40, and ge adjusted the stability requirements imposed on the lower control arm 40. Overall, the lower wishbone 40 is configured as a double wishbone, which two transverse to the roadway struts 43; 44, which are interconnected by means of a substantially X-shaped reinforcement section 45. It is certainly possible to attach the lower wishbone 40 at another suitable location of the Achsschenkelträgers 5, and it is possible to provide the lower arm 40 with a different outer shape, or even instead of a wishbone to use more.

3 shows an alternative embodiment of a stub axle carrier 5 according to the invention. The difference from the stub axle carrier 5 illustrated in FIGS. 1 and 2 is the different configuration of the axle-side end 23 of the stub axle carrier 5. The axle-side end 23 of the stub axle carrier 23 shown in FIG. 3 illustrated Achsschenkelträgers 5 has a fork 46, which has an upper end portion 47 and a lower end portion 48. The illustrated in Fig. 3 lower end portion 48 of the fork 46 is disposed between the upper bearing 19 and the lower bearing point 20 of the steering knuckle 2. The upper end portion 47 of the fork 46 rests on the upper bearing point 19 of the steering knuckle 2. Both end portions 47; 48 of the fork 46 each have a continuous mounting hole 49; 50 on. The mounting holes 49; 50 of the two end portions 47; 48 of the fork 46 are each coaxial with each other and to the openings 21 '; 22 'in the bearings 21 22 of the two bearings 19; 20 aligned so that a kingpin 4 can be performed during assembly through all these openings to form a common form-fitting interconnected assembly consisting of the stub axle 2, the kingpin 4 and the stub axle 5. Designation Independent wheel suspension

journal

wheel hub

kingpin

steering knuckle

attachment section

fastening opening

mounting portion

Bearing with kingpin

Upper wishbone

Steering-arm-side end portion of the one upper wishbone Steering-end end portion of the second upper wishbone Mounting bolts

Vehicle frame side end portion of the one upper wishbone Vehicle frame side end portion of the second upper wishbone Vehicle frame side bearing of the one upper wishbone Vehicle frame side bearing of the second upper wishbone Upper bearing point of the steering knuckle

'Breakthrough in the upper bearing point of the steering knuckle

Lower bearing point of the steering knuckle

'Breakthrough in the lower bearing of the steering knuckle

Upper bearing in the upper bearing point of the steering knuckle

Lower bearing in the lower bearing of the steering knuckle

'Opening in the upper bearing

'Opening in the lower bearing

Achsschenkelseitiges end of the steering knuckle

Mounting opening of the steering knuckle carrier

protective cover

closure element 27 First extension section of the steering knuckle carrier

28 First bending section of the steering knuckle carrier

29 second extension section of the steering knuckle carrier

30 Second bending section of the steering knuckle carrier

31 Third extension section of the steering knuckle carrier

32 Upper radius of the first bending section of the steering knuckle carrier

33 Lower radius of the first bending section of the steering knuckle carrier

34 Upper radius of the second bending section of the steering knuckle carrier

35 lower radius of the second bending portion of the steering knuckle

36 fastener for mounting a vibration damper

37 vibration damper

38 Breakthrough in the steering knuckle

39 bearing for the lower wishbone

40 Lower wishbone

40 'recess in the lower arm

40 "recess in the lower arm

40 '"recess in the lower arm

41 fastener

42 spring element

43 strut

44 strut

45 reinforcement section

46 bifurcation of the axle-side end of the steering knuckle carrier

47 Upper end section of the fork

48 Lower end portion of the crotch

49 mounting opening in the upper end portion of the fork

50 mounting opening in the lower end portion of the fork

51 Section with reduced material thickness

A axis of rotation of the steering knuckle

B Rotary axis of the upper arm

C axis of rotation of the lower arm

S longitudinal axis of the vibration damper

Claims

claims

1 . Independent wheel suspension (1) for a commercial vehicle comprising:

A steering knuckle (2) rotatably mounted on a steering knuckle pin (4) about a first axis of rotation (A) and having a wheel hub (3),

A, by the kingpin (4) with the steering knuckle (2) connected to the steering knuckle (5),

A vibration damper (37) as well as a spring element (42), which in each case can be fixed to a fastening element (36; 41) on the steering knuckle carrier (5) and to another fastening element of the vehicle body,

At least one upper transverse link (10, 11) and at least one lower transverse link (40),

wherein the wishbones (10; 1 1; 40) on the one hand are connected at least indirectly to the steering knuckle (2) and on the other hand to another fastening means of the vehicle body, the upper wishbone (10; 11) being mounted above the steering knuckle support (5). is arranged and wherein the lower arm (40) in the installed position below the upper transverse link (10; 1 1) is arranged,

characterized in that the upper transverse link (10; 1 1) is fixed to the kingpin (4) and is rotatably mounted about a second axis of rotation axis (B) of the upper transverse link (10; 1 1), and wherein the lower transverse link (40) on the stub axle carrier (5) about a third axis of rotation of the axle (C) of the lower arm (40) is rotatably mounted, wherein the third axis of the axle axis of rotation (C) of the lower arm (40), radially from the first axis of rotation (A) of the stub axle ( 2) is spaced.

2. Independent wheel suspension for a commercial vehicle according to claim 1, characterized in that the second axis of rotation axis (B) of the upper arm (10; 1 1), the first axis of rotation (A) of the steering knuckle (2) intersects.

3. Independent wheel suspension for a commercial vehicle according to claim 1 or 2, characterized in that the longitudinal extension axis (S) of the vibration damper (37) the third axis of the axle axis of rotation (C) of the lower arm intersects.

4. independent wheel suspension for a commercial vehicle according to one of claims 1 to 3, characterized in that the third axis of rotation axis (C) of the lower arm (40), and the second axis of rotation axis (B) of the upper arm (10; 1 1) in a gap between the steering knuckle (2) and the spring element (42) are arranged.

5. independent wheel suspension for a commercial vehicle according to one of claims 1 to 4, characterized in that the stub axle (5) is designed S-shaped and a first extension portion (27), a second extension portion (29) and a third extension portion (31 ), which are interconnected by a first bending section (28) and a second bending section (30).

6. Independent wheel suspension for a commercial vehicle according to one of claims 1 to 5, characterized in that the stub axle carrier (5) has a fastening element (36) for fastening the vibration damper (37).

7. Independent wheel suspension for a commercial vehicle according to one of claims 1 to 6, characterized in that the stub axle carrier (5) has a fastening element (41) for fastening a vehicle frame supporting the spring element (42).

8. Independent wheel suspension for a commercial vehicle according to one of claims 1 to 7, characterized in that the stub axle carrier (5) has a portion (51) with a recess or with a reduced material thickness.

9. Independent wheel suspension for a commercial vehicle according to one of claims 1 to 8, characterized in that the stub axle carrier (5) at its end facing the steering knuckle (2) end has a fork (46) having an upper End portion (47) and a lower end portion (48).

10. independent wheel suspension for a commercial vehicle according to one of claims 1 to 9, characterized in that the steering knuckle (2) has two of the wheel hub (3) facing away from the surface of the steering knuckle (2) projecting bearing points (19, 20) which an engagement formation with the end portions (47; 48) of the fork (46) of the steering knuckle (5).