WO1997013665A1

WO1997013665A1 - Assembly for axle

Info

Publication number: WO1997013665A1
Application number: PCT/EP1996/004465
Authority: WO
Inventors: Eckart Op Den Camp; Ulrich Seuser
Original assignee: Lucas Industries Public Limited Company
Priority date: 1995-10-13
Filing date: 1996-10-14
Publication date: 1997-04-17
Also published as: DE19538212A1

Abstract

The invention concerns a motor vehicle assembly for axle (10) comprising a steering knuckle (14) which is made of a first material and comprises points of articulation (24, 26) for securing wheel-suspension or steering components. The assembly (10) further comprises a combination element (34) which is made of a second material, differing from the first material, and comprises a wheel bearing housing (36) and a brake mounting. The combination element (34) or the brake mounting thereof absorbs at least the peripheral forces occurring during braking in forward travel. The combination element (34) and the steering knuckle (14) each have a continuous plane end face (46 and 48, respectively) disposed perpendicular to a wheel axis (A). The end faces (46, 48) face each other and together define, between the combination element (34) and the steering knuckle (14), a continuous flat separating surface which intersects the wheel axis (A), preferably at a right-angle. The combination element (34) and the steering knuckle (14) can be interconnected along this separating surface. The assembly for axle (10) according to the invention can be produced economically and easily adapted to different requirements without substantial modifications to its design.

Description

Axle assembly

The invention relates to an axle assembly, in particular for the front axle of a front-driven motor vehicle, according to the preamble of claim 1.

Such an axle assembly is known from DE-A-33 40 442. The construction described there uses stamped and pressed sheet metal components to save weight. No further details regarding the material used can be found in this document. The steering knuckle of the construction shown is matched to the combination component and does not allow either a disc brake or a drum brake to be used on the axle assembly without modifications.

In today's automotive industry, attempts are being made to reduce the vehicle's unladen weight, which has steadily increased due to additional safety features and comfort equipment, in order to reduce the vehicle's fuel consumption. These efforts affect almost all parts of a motor vehicle and do not stop at such sensitive parts as chassis components and brakes. Although knuckles or chassis parts made of aluminum or aluminum alloys are known from sports and racing car construction, for example, which are very light and yet stable, these are very expensive and production-intensive constructions which are suitable for large-scale use for cost reasons, but are also unsuitable because of the time-consuming production.

The invention is based on the object of providing an axle assembly which is lighter than conventional constructions and which can be produced more cost-effectively and quickly and which nevertheless has sufficient stability. In addition, it should be possible to use either a disc brake or to attach a drum brake to the axle assembly without having to change the axle assembly as a whole.

This object is achieved according to the invention by an axle assembly which has the features specified in claim 1.

The axle assembly construction according to the invention can be produced inexpensively by the mutually facing, continuously flat end faces, since such flat end faces enable a part to be machined to be clamped in well and thus to be easy to machine. In addition, the separation of the combination component and steering knuckle along a continuous plane has the advantage that either a disc brake or a drum brake can be attached to the steering knuckle assembly without a substantial change in the steering knuckle. Finally, in the axle assembly according to the invention, the materials of the combination component and axle stub can be selected in accordance with the intended use, as a result of which the axle assembly according to the invention can be kept light yet inexpensive. For reasons of weight, the steering knuckle will usually consist of aluminum or an aluminum alloy, while the combination component can, for example, consist of more stable cast steel in order to better withstand the high surface pressures which are exerted on the brake support of the combination component by circumferential forces generated when braking, if one Disk brake is attached to the axle assembly. On the other hand, the combination component can also consist of a lighter material, for example an aluminum alloy, if problems due to high surface pressures are not to be expected, for example if a drum brake is attached to the axle assembly, for further weight saving. Thus, although according to the invention the combination component and the steering knuckle can consist of an aluminum alloy, they are different from one another

Aluminum alloys and therefore different materials, because the requirements placed on a steering knuckle changes differ significantly from the requirements placed on the combination component. For example, the material of the steering knuckle must be very tough, while, for example, a combination component used in conjunction with a drum brake must be very tight, ie it must have only a little and no large pores. Instead of the different aluminum alloys mentioned, magnesium alloys can also be used.

The wheel bearing housing and the brake support of the combination component are preferably made in one piece with one another, but the brake support can also be a separate component connected to the combination component.

Although the axle assembly according to the invention is designed in particular for use on the front axle of a motor vehicle, it can also be used on the rear axle of a motor vehicle without any problems, in particular in connection with the multi-link rear axles which are increasingly used today.

In one embodiment of an axle assembly according to the invention, the steering knuckle consists of aluminum or sheet steel parts which preferably enclose a circumferential cavity in order to increase the stability of the steering knuckle. To further increase stability, this cavity can contain stiffening elements which are adapted to the shape of the cavity and which can be part of components which define the articulation points for fastening the wheel suspension or steering elements. These articulation points can be eyes, for example.

In another embodiment of an axle assembly according to the invention, the steering knuckle is a cast aluminum part on which the articulation points for the wheel suspension or steering elements are formed in one piece. In preferred embodiments of the axle assembly according to the invention, the steering knuckle has a holder for a speed sensor. The axle assembly according to the invention can thus be used without any problems in vehicles which are equipped with an anti-lock braking system and / or a traction control system or similar systems which require wheel speed signals.

In a preferred embodiment of an axle assembly according to the invention, the brake support of the combination component is a first brake support arm of a brake support serving to fasten a disc brake to the axle assembly. The first brake carrier arm is advantageously made in one piece with the wheel bearing housing and has an L-shaped cross-sectional shape. The first brake carrier arm is the arm of the brake carrier which absorbs the circumferential forces which arise during braking during forward travel and which are introduced into it via the brake lining carrier plates. In this case, the combination component therefore preferably consists of steel. With a modified one

Embodiment is also a second brake carrier arm, which absorbs the circumferential forces generated during braking in reverse, part of the combination component.

In yet another embodiment of the axle assembly according to the invention, the first brake carrier arm is designed so that it can absorb both the circumferential forces that occur during braking in forward travel and the circumferential forces that occur during braking in reverse travel. In contrast to the two previously described embodiments, however, conventional brake pads cannot be used in this embodiment. Instead, brake linings are required whose lining carrier plate is designed in such a way that peripheral forces can be transmitted to the first brake carrier arm regardless of the direction of rotation.

In a further embodiment of an axle assembly according to the invention, the second brake associated with the brake carrier is low-arm part of the steering knuckle and has an in particular L-shaped cross-sectional shape corresponding to the first brake arm. This embodiment makes it possible to form the second brake carrier arm from the material of the steering knuckle, which is preferably an aluminum alloy, in order to save weight. Since the circumferential forces that occur when braking in reverse are usually significantly lower, the surface pressures that occur can also withstand a brake carrier arm made of an aluminum alloy, unless a construction is chosen without the first, which describes the first brake carrier arm independently of the resulting circumferential forces of the direction of rotation of the braked wheel.

Should a drum brake instead of a disc brake on the

Axle assembly are attached, then, in preferred embodiments of axle assemblies according to the invention, the brake support of the combination component is used for fastening a drum brake to the axle assembly and is formed in one piece with the wheel bearing housing as a support ring which bears an abutment which supports the circumferential forces arising during braking takes up, which are initiated via the brake shoes. For reasons of weight, such a combination component preferably consists of an aluminum alloy and can be a cast part or a forged part.

In a modification of the last-described embodiment of an axle assembly according to the invention, the abutment which absorbs the circumferential forces arising during braking and / or a brake cylinder is formed in one piece with the combination component or the support ring.

In all embodiments of the axle assemblies according to the invention, the combination component can be made of steel or of a suitable light metal alloy. However, the combination component is preferably made of steel if it is to be connected to a disc brake and is made of one Light alloy made when a drum brake is to be attached to the axle assembly. For weight reasons, the steering knuckle is preferably made of a light alloy, but it can also be made of a steel alloy.

Three preferred exemplary embodiments of an axle assembly according to the invention are explained in more detail below with reference to the accompanying figures. It shows:

1 shows an exploded cross-sectional view of a first exemplary embodiment of an axle assembly according to the invention, which is provided for receiving a disc brake,

2 shows a top view corresponding to the top view II-II from FIG. 1 of a second embodiment of an axle assembly according to the invention, somewhat modified compared to the first embodiment,

3 shows an exploded cross-sectional view of a third exemplary embodiment of an axle assembly according to the invention, in which the steering knuckle, not shown, is connected to a drum brake, and

4 shows a spatial representation of a combination component shown in FIG. 3, which integrates a wheel bearing housing and a brake support.

1 shows a first exemplary embodiment of an axle assembly, generally designated 10, which is provided for connection to a disc brake 12.

The axle assembly 10 includes a steering knuckle 14 which is cast in one piece from an aluminum alloy and has a ring-shaped one Base body 16, from which a support arm 18 projects axially and radially. The support arm 18 forms the lower attachment point of a strut (not shown here) of a front wheel suspension, which can be attached to the support arm 18 by means of two screws. Such struts, which combine a shock absorber and a coil spring concentrically surrounding it, are also known under the term McPherson suspension and are widely used in today's cars. Two eyes 20 and 22, which form articulation points 24 and 26, also project essentially axially away from the annular base body 16 of the steering knuckle 14. The articulation point 24 formed by the eye 20 serves to fasten a tie rod belonging to the steering, while the articulation point 26 formed by the eye 22 serves to fasten a wishbone of the front wheel suspension. Finally, a holder 28 extends from the annular base body 16 of the steering knuckle 14, in the through bore of which a speed sensor 30 can be inserted, which is fixed by means of a screw 32. The support arm 18, the eyes 20 and 22 and the holder 28 are integrally connected to the annular base body 16.

The axle assembly 10 also includes a combination component 34, which has an axially extending, ring-shaped wheel bearing housing 36 and two integrally connected, in cross-sectional view, L-shaped brake support arms, of which only a first brake support arm 38 is shown in FIG and which together form a brake carrier used for fastening the disc brake 12. With its short leg 38a, the first brake carrier arm 38 absorbs the circumferential forces which are introduced when the brake carrier plates 39 of the disk brake 12 move forward into the first brake carrier arm 38 by the brake carrier plates 39 being supported on the short leg 38a in the circumferential direction. The combination component 34 is made of spheroidal graphite cast iron and takes in the wheel bearing housing 36 a conventional, double-row spherical bearing 40 with a two-part inner ring 42 and a one-part outer ring 44.

The combination component 34 and the steering knuckle 14 each have an end face 46 or 48 which intersects the wheel axis A, is arranged perpendicular to it and is continuously flat. Both end faces 46 and 48 face each other and define the continuously flat separating surface between the combination component 34 and the steering knuckle 14, which constitutes the variability of the construction shown and enables either a disc brake or a drum brake with virtually no change in the steering knuckle to attach to it. Between the flat end faces 46 and 48 of the combination component 34 and the steering knuckle 14 is an annular and substantially flat sheet metal part 50 is arranged, which as

Dirt shield is used and in particular to keep splash water away from a brake disk 52 of the disk brake 12.

A wheel hub 54, on the flange 56 of which the brake disc 52 is fastened by means of several screws (not shown), projects with its axially extending stub shaft 58 into the wheel bearing housing 36. The outer circumferential surface of the stub shaft 58 supports the axle assembly 10 in the assembled state the two-part inner ring 42 of the ball bearing 40, while the outer ring 44 is held in the wheel bearing housing 36. The wheel hub 54 has an axial passage recess, which is prepared with a multi-groove profile 60 for receiving a correspondingly configured end region of a drive shaft (not shown), which extends to the right in FIG. 1 through the steering knuckle 14.

The steering knuckle 14 and the combination component 34 are screwed together by means of four screws 62, each of which extends through a corresponding recess 64 in the steering knuckle 14 and into an internal thread 66 in the combination component 34. The disc brake 12 is fastened to the brake carrier by means of two screws 68, the threaded end of which cuts 68a engage in a bore 70 provided on the combination component 34 and provided with an internal thread.

FIG. 2 shows a second embodiment of an axle assembly 10 that is somewhat modified compared to the first embodiment from FIG. In contrast to the first exemplary embodiment, in the second exemplary embodiment only the first brake carrier arm 38 is made in one piece with the combination component 34 or its wheel bearing housing 36, while the second brake carrier arm 72 is made in one piece with the steering knuckle 14 made of cast aluminum. In addition, the first brake carrier arm 38 in the second embodiment, in cooperation with the lining carrier plates 39, is able to absorb both the circumferential forces that occur during braking in forward travel and also during braking in reverse travel. For this purpose, the first brake carrier arm 38 has hook-shaped extensions 74 into which corresponding hooks 76 formed on each lining carrier plate 39 engage. Springs 78 between the lining carrier plates 39 and the first lining carrier arm 38 or the second lining carrier arm 72 prevent rattling noises caused by the brake linings. In the second exemplary embodiment, the second brake support arm 72 is therefore only used to properly guide the brake linings and has almost no supporting function.

A third exemplary embodiment of an axle assembly 10 is shown in FIG. In contrast to the first two exemplary embodiments, a drum brake 80 is part of the axle assembly 10 in the third embodiment. This requires a somewhat modified and therefore designated 34 'combination component which, in addition to the wheel bearing housing 36, has an abutment 82 which serves as a brake support , which is carried by a support ring 84 and is formed integrally therewith, which is connected in one piece to the wheel bearing housing 36 and surrounds it. In the exemplary embodiment shown in FIG. 3, a brake cylinder 86 is also formed in one piece with the combination component 34 'and is supported by the support ring 84 like the abutment 82. The combination component 34 'also has the flat end face 46, which faces the likewise flat end face 48 of the steering knuckle 14, which is not shown in FIG.

In contrast to the combination component 34 of the first two exemplary embodiments, the combination component 34 ', which is shown spatially in FIG. 4, is a part cast from an aluminum alloy or else an aluminum forged part. The ball bearing 40 or even its outer ring 44 can already be cast in the casting mold in a cast version of the combination component 34 ', so that it or he does not have to be subsequently introduced into the wheel bearing housing 36.

The drum brake 80 includes an assembly 90 comprising the brake shoes 88 and a brake shoe adjusting device and a brake drum 92 which is plugged onto a wheel hub 54 'from the outside and is fastened to it by means of screws (not shown). The drum brake 80 can additionally be provided with a parking brake device. The wheel hub 54 'represents an embodiment of the kind used for a non-driven wheel, but the wheel hub 54 can also be used just as well if the axle assembly 10 is provided for a driven wheel.

Claims

claims

1. axle assembly (10), in particular for the front axle of a front-driven motor vehicle, with

- A steering knuckle (14) which has articulation points (24, 26) for fastening wheel suspension or steering elements, and

- A combination part (34, 34 ') which can be connected to the steering knuckle (14) along a separating surface and which comprises a wheel bearing housing (36) and a brake support and at least absorbs the circumferential forces which arise during braking during forward travel, characterized in that - the steering knuckle (14) made of a first material and that

Combination component (34, 34 ') consists of a second material which is different from the first material, and

- The separating surface between the steering knuckle (14) and the combination component (34, 34 ') is a continuously flat surface that preferably cuts the wheel axis (A) at right angles, and that has flat end faces (46, 48) of the combination component (facing each other) 34, 34 ') and the steering knuckle (14) is defined.

2. axle assembly according to claim 1, characterized in that the steering knuckle (14) consists of Alumi¬ nium- or sheet steel molded parts, which in particular enclose a circumferential cavity.

3. axle assembly according to claim 1, characterized in that the steering knuckle (14) is an Aluguß¬ part on which the articulation points (24, 26) are integrally formed.

4. axle assembly according to one of claims 1 to 3, characterized in that the steering knuckle (14) has a Halt¬ tion (28) for a speed sensor (30).

5. Axle assembly according to one of the preceding claims, characterized in that the brake support of the Kombina¬ tion component (34) is a first brake support arm (38) of a for mounting a disc brake (12) on the axle assembly serving as a brake support, the first brake support arm (38) is preferably made in one piece with the wheel bearing housing (36) and has an in particular L-shaped cross-sectional shape.

6. Axle assembly according to claim 5, characterized in that the first brake carrier arm (38) so¬ probably takes the braking forces in forward driving as well as the braking forces occurring in reverse driving peripheral forces.

7. axle assembly according to claim 5 or 6, characterized in that a second brake carrier arm associated with the brake carrier (72) of in particular L-shaped cross-sectional shape is part of the steering knuckle (14).

8. Axle assembly according to one of claims 1 to 4, characterized in that the brake support of the Kombina¬ tion component (34 ') for fastening a drum brake (80) on the axle assembly serving, integrally formed with the Rad¬ bearing housing (36) support ring ( 84), which carries an abutment (82).

9. Axle assembly according to claim 8, characterized in that the abutment (82) is in one piece with the support ring (84).

10. Axle assembly according to one of the preceding claims, characterized in that the combination component (34, 34 ') consists of steel or an aluminum alloy.