GB2561897A

GB2561897A - Suspension bush

Info

Publication number: GB2561897A
Application number: GB1706779.4A
Authority: GB
Inventors: Morrad James; Whear Frank; Langton Alex; Randle Pete
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2017-04-28
Filing date: 2017-04-28
Publication date: 2018-10-31
Also published as: GB201706779D0

Abstract

A vehicle suspension bush 10 has an outer part 20 having an inner surface 21, and an inner part 30 having an outer surface 33 and situated within the outer part webs 40 joining the surfaces 21,33. The webs are formed integrally with the inner and outer parts (e.g. cut from a unitary extruded aluminium alloy or composite and machined in one operation; an additive manufacture process; or an assembly of components brazed or glued together). The bush can have anti-rotation features e.g. recesses 50a, 50b, 50c; and have symmetry and concentric parts. The inner part 30 can have an axial length greater than the outer part 20, and the parts have different radial thicknesses. The bush can be an interference fit in an aperture of a vehicle suspension component (80, figs 5 & 6), the aperture having a liner (86, fig 6). The bush 10 has the dynamic characteristics of a rigid bush and the load management and insertion characteristics of a compliant bush.

Description

(54) Title of the Invention: Suspension bush

Abstract Title: Vehicle suspension bush with webs (57) A vehicle suspension bush 10 has an outer part 20 having an inner surface 21, and an inner part 30 having an outer surface 33 and situated within the outer part webs 40 joining the surfaces 21,33. The webs are formed integrally with the inner and outer parts (e.g. cut from a unitary extruded aluminium alloy or composite and machined in one operation; an additive manufacture process; or an assembly of components brazed or glued together). The bush can have anti-rotation features e.g. recesses 50a, 50b, 50c; and have symmetry and concentric parts. The inner part 30 can have an axial length greater than the outer part 20, and the parts have different radial thicknesses. The bush can be an interference fit in an aperture of a vehicle suspension component (80, figs 5 & 6), the aperture having a liner (86, fig 6). The bush 10 has the dynamic characteristics of a rigid bush and the load management and insertion characteristics of a compliant bush.

Fig. 1

At least one drawing originally filed was informal and the print reproduced here is taken from a later filed formal copy.

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Suspension Bush

TECHNICAL FIELD

The present disclosure relates to a bush for the suspension assembly of a vehicle. The present disclosure further relates to a suspension component or suspension assembly having the bush, and a vehicle having a suspension component or suspension assembly having the bush. A method of manufacturing a bush for a suspension component or suspension assembly of a vehicle is also disclosed.

BACKGROUND

Various bush designs are used within vehicle suspension systems. Such bushes may be termed either compliant or non-compliant. Non-compliant bushes are typically formed from a solid piece of metal and can lead to hard ride and undesirable NVH characteristics. Compliant bushes may be formed predominantly from rubber or nylon. Such compliant bushes have softer ride and more desirable NVH characteristics. Compliant bushes may however degrade during the life of the vehicle and require replacement.

It is an aim of the present invention to provide a bush which has the dynamic characteristics of a rigid bush and the load management and insertion characteristics of a compliant bush.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a bush for a vehicle, a suspension assembly for a vehicle which includes the bush, a vehicle having the suspension assembly, and a method as claimed in the appended claims.

According to an aspect of the present invention there is provided a bush for a vehicle comprising:

an outer part, having an inner surface; an inner part, having an outer surface;

the inner part being situated within the outer part; and at least two webs joining the inner surface of the outer part to the outer surface of the inner part;

wherein the webs are formed integrally with the inner and outer parts.

In one embodiment of the present invention there is provided a bush which is formed as a single piece from a common material. Integral formation of the webs with the inner and outer parts ensures that there is no requirement for fasteners or other joining means to be used in order to connect the inner and outer parts to one another. The desired compliance characteristics can be achieved by variation of the number, geometry and positioning of the webs with respect to the inner and outer parts. More specifically, the geometry of the webs and their number, location and radial orientation are configured such that the radial compliance for load management and insertion characteristics of the bush correspond to those of a compliant bush, while the dynamic characteristics of the bush correspond to those of a rigid bush.

Depending upon the material from which it is formed, the bush of the present invention may be lighter than a comparatively sized rigid or compliant bush.

The outer part may be at least partially cylindrical. The inner part may be at least partially cylindrical. In one embodiment of the present invention both the outer part and the inner part may be at least partially cylindrical. More specifically, both the outer part and the inner part may be substantially cylindrical.

The outer part and the inner part may be arranged concentrically about a common axis.

The bush may comprise three, four or more webs joining the inner surface of the outer part to the outer surface of the inner part. As noted above, configuration of the webs may be undertaken such that desired characteristics such as, for example, compliance, deflection, vibration isolation and such like are provided by the bush. The webs may, for example, be equidistantly spaced from one another.

The inner part may be provided with an alignment feature for use when fitting the bush to a vehicle, vehicle suspension assembly or suspension component. The alignment feature may be a recess of an inner surface of the inner part. Such alignment features ensure that the bush is correctly aligned when fitted to a suspension component or suspension assembly.

The outer part and the inner part may each have an axial length, and the inner part axial length may be greater than the outer part axial length. In an alternative embodiment, both the inner and outer parts may have the same axial length.

The webs each have an axial length, and the axial length of each web may be at least as long as the inner part axial dimension. The axial length at each end of a web may be equal to that of the respective inner and outer part to which it is joined.

The webs may be disposed in an arrangement that in cross-section has one axis of symmetry. In an alternative embodiment, the webs may be disposed in an arrangement that in cross-section has two axes of symmetry.

The radial thickness of the outer part may be greater than the radial thickness of the inner part.

The bush may be formed from a single unitary piece of metal. In an embodiment of the invention the metal may be an extrudable alloy, for example an aluminium alloy. In an alternative embodiment of the present invention the bush may be formed from a composite material.

According to another aspect of the invention, there is provided a suspension assembly for a vehicle, the suspension assembly comprising:

a suspension component; and a bush according to the preceding aspect, wherein the suspension component and bush are configured so as to be retainable in association with one another.

The suspension component may, for example, be a suspension frame.

The suspension component may include an aperture, and the bush may be configured to be received in the aperture to permit retention of the suspension component and bush in association with one another. The aperture of the suspension component and outer diameter of the cylindrical outer component of the bush may be sized such that an interference fit is provided therebetween. The aperture of the suspension component may be provided with a liner.

The external dimensions of the bush may mirror those of a prior art compliant bush. As such, a bush in accordance with an embodiment of the present invention may be used in direct replacement of a prior art complaint bush in a suspension assembly.

According to another aspect of the present disclosure, there is provided a vehicle having a suspension assembly as described in the preceding aspect.

According to another aspect of the present disclosure, there is provided a method of forming a bush for a vehicle, the method comprising the steps of:

extruding a bush piece, the bush piece having an outer part with an inner surface, an inner part with an outer surface, the inner part being situated concentrically within the outer part, and at least two webs joining the inner surface of the outer part to the outer surface of the inner part; and cutting the bush piece into at least one bush.

The method may include the feature of machining the bush such that the axial length of the inner part is greater than the axial length of the outer part. In another embodiment, the steps of cutting the bush piece into at least one bush section and machining the bush section may be performed in a single step.

According to another aspect of the present invention there is provided a bush for a vehicle comprising:

an outer part, having an inner surface; an inner part, having an outer surface;

wherein the webs are formed integrally with one of the inner and outer parts.

The bush may thus be of a two piece construction which requires assembly before use.

an outer part, having an inner surface; an inner part, having an outer surface;

wherein the webs are formed separately to the inner and outer parts.

The bush may thus be of a multi-part construction which requires assembly before use.

Assembly of the bush as described in the aspects noted above may include connecting the parts or pieces by, for example, brazing or the use of adhesive.

Within the scope of the application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or in any combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a perspective view of a bush according to an embodiment of the present disclosure;

Figure 2 shows a side view of the bush of figure 1;

Figure 3 shows an end view of the bush of figure 1;

Figure 4 shows a longitudinal cross-sectional view of the bush of figure 1;

Figure 5 shows a plan view of a vehicle suspension assembly;

Figure 6 shows a perspective view of a bush according to an embodiment of the present disclosure located to the vehicle suspension assembly;

Figure 7 shows another perspective view of a bush according to an embodiment of the present disclosure located on the vehicle suspension assembly; and Figure 8 shows a vehicle having the bush and/or suspension assembly.

DETAILED DESCRIPTION

As shown in figures 1 to 4, there is provided a bush 10 for a vehicle according to an embodiment of the present disclosure. In the embodiment shown the bush 10 comprises: an outer part 20, an inner part 30, and four webs 40 which extend between the outer and inner parts 20, 30. In the embodiment shown, the outer and inner parts 20,30 are cylindrical. In alternative embodiments, not shown, one or both of the inner and outer parts may be noncylindrical or partially cylindrical. For example, the outer part 20 may be provided with one or more flats which, in use, assist in the alignment of the bush 10 within a suspension assembly and/or seek to reduce the possibility of rotation of the bush 10 within the suspension assembly.

The cylindrical outer part 20 defines a hollow cylinder having an inner surface 21 and an outer surface 23. The cylindrical outer part 20 has a first end 25 and a second end 26 (best seen in figure 2). The cylindrical outer part 20 has an axial length in the direction of axis A between the first end 25 and the second end 26. The cylindrical outer part 20 has a radial thickness between the cylindrical outer part inner surface 21 and the cylindrical outer part outer surface 23.

The cylindrical inner part 30 defines a hollow cylinder having an inner surface 31 and an outer surface 33. The cylindrical inner part 30 has a first end 35 and a second end 36 (best seen in figure 2). The cylindrical inner part 30 has an axial length in the direction of axis A between the first end 35 and the second end 36. As shown in figure 2, the axial length of the cylindrical inner part 30 is greater than the axial length of the cylindrical outer part 20. The cylindrical inner part 30 has a radial thickness between the cylindrical inner part inner surface 31 and the cylindrical outer part outer surface 33. The radial thickness of the cylindrical outer part 20 is greater than the radial thickness of the cylindrical inner part 30. It will be appreciated that in other configurations of the bush the radial thicknesses of the outer and inner parts 20,30 may be substantially the same. Alternatively, the radial thickness of the inner part 30 may be greater than that of the outer part 20. In an alternative embodiment the axial lengths of the outer and inner parts 20,30 may be approximately equal.

The cylindrical inner part 30 has an alignment feature 50 for use when fitting the bush 10 to a vehicle or vehicle assembly. The alignment feature 50 takes the form of three recesses 50a, 50b, 50c. The three recesses of the alignment feature 50 may be arranged to one side of the inner part 30, such that they are not symmetrical about either of axes X or Y (best seen in figure 3). The alignment feature can act to allow poka-yoke assembly to a shaft inside the cylindrical inner part 30.

Each web 40 has a first end 45 and a second end 46. The webs 40 are the same shape as each other. The webs 40 are substantially elongate. In figures 1 and 2 the webs 40 are shown with tapered ends. In figure 4, the webs 40 are shown with straight ends. The webs each have an axial length that is at least as long as the axial length of the cylindrical outer part 20. In figure 4, the webs 40 do not extend to the ends 35, 36 of the inner part 30. As shown in figure 2, the axial length of each web 40 is at least as long as the axial length of the cylindrical inner part 30.

The cylindrical inner part 30 is situated within the cylindrical outer part 20. The cylindrical outer part 20 and the cylindrical inner part 30 are arranged concentrically about common axis A.

The webs 40 each join the outer surface 33 of the cylindrical inner part 30 to the inner surface 21 of the cylindrical outer part 20. The webs 40 are equidistantly spaced from one another. The webs 40 are formed integrally with the cylindrical inner and outer parts 30, 20. As shown by figure 3, the webs 40 are disposed in an arrangement that in cross-section has two axes of symmetry, shown by axes X, Y. As shown in figure 3, the webs 40 are not aligned with a radial direction of the bush 40.

As shown by figure 2, first end 45 of each web 40 tapers between the cylindrical inner part first end 35 and the cylindrical outer part first end 25. Similarly, the second end 46 of each web 40 tapers between the cylindrical inner part second end 36 and the cylindrical outer part second end 26.

In one embodiment of the present invention the bush 10 is formed from a single piece of metal. More specifically, the bush 10 is a single unitary piece of extrudable aluminium alloy. In an alternative embodiment, the bush 10 may be formed from a composite material.

The bush 10 of the present invention may be formed by extrusion. A length of extrusion may be produced which has a desired cross sectional configuration. The length of extrusion is then cut to a desired length in order to form the bush 10. Machining operations may be undertaken to conform one or both ends of the bush 10 to a desired configuration, for example to provide the inner part 30 with a greater axial length than the outer part 20. The cutting and machining operations may be combined into a single operation.

Figure 5 shows a plan view of a vehicle suspension assembly 70 comprising a suspension component 80 and four bushes 10. Enlarged sections of figure 5 show the suspension component 80 and the bush 10 being configured so as to be retainable in association with one another.

Figure 6 shows a perspective view of a bush 10 received in the vehicle suspension component 80. The vehicle suspension component 80 has a first aperture 81 which receives the bush 10. The bush 10 is configured to be received in the aperture 81 to permit retention of the suspension component 80 and bush 10 in association with one another. The aperture 81 of the suspension component 80 and the outer diameter of the cylindrical outer part 20 of the bush 10 are sized such that an interference fit is provided therebetween. The aperture 81 is provided with a cylindrical liner 85. The aperture 81 and cylindrical liner 85 are sized such that an interference fit is provided between the bush 10 and the suspension component 80.

Figure 7 shows another perspective view of a bush 10 received in the vehicle suspension component 80. The vehicle suspension component 80 has a second aperture 82 which receives the cylindrical outer part 20 of the bush 10.

The bush 10 is configured to be received in the aperture 82 to permit retention of the suspension component 80 and bush 10 in association with one another. The aperture 82 of the suspension component 80 and the outer diameter of the cylindrical outer part 20 of the bush 10 are sized such that an interference fit is provided therebetween. The aperture 82 is provided with a cylindrical liner 86. The aperture 82 and cylindrical liner 86 are sized such that an interference fit is provided between the bush 10 and the suspension component 80.

Figure 8 shows a vehicle 100 having a bush 10 and/or a suspension assembly 70 as described above.

In the embodiments of the invention described above, the bush 10 is described as being of a single piece construction from either metal or a composite material. In alternative embodiments, the bush 10 may be of a multipart construction and thus require assembly.

For example, the webs 40 may be formed integrally with the inner part 30 and have distal ends that locate to features of the outer part 20. In such an embodiment, the individual components of the bush 10 may be connected to one another by, for example, brazing or the use of adhesive.

In the embodiments of the invention described above, the bush 10 is described as being formed by extrusion. In alternative embodiments, the bush may be formed by other manufacturing process. For example, the bush 10 may be formed by an additive manufacture process.

Claims

1. A bush for a vehicle comprising:

an outer part, having an inner surface; an inner part, having an outer surface;

wherein the webs are formed integrally with the inner and outer parts.

2. A bush according to claim 1, wherein the outer part is at least partially cylindrical.

3. A bush according to claim 1 or claim 2 wherein the inner part is at least partially cylindrical.

4. A bush according to any preceding claim, wherein the outer part and the inner part are arranged concentrically about a common axis.

5. A bush according to any preceding claim, wherein the bush comprises three webs joining the inner surface of the outer part to the outer surface of the inner part.

6. A bush according to any preceding claim, wherein the bush comprises four webs joining the inner surface of the outer part to the outer surface of the inner part.

7. A bush according to any preceding claim, wherein the webs are equidistantly spaced from one another.

8. A bush according to any preceding claim, wherein the inner part is provided with an alignment feature for use when fitting the bush to a vehicle or vehicle assembly.

9. A bush according to claim 6, wherein the alignment feature is a recess of an inner surface of the inner part.

10. A bush according to any preceding claim, wherein the outer part and the inner part each have an axial length, and the inner part axial length is greater than the outer part axial length.

11. A bush according to any preceding claim, wherein the webs each have an axial length, and the axial length of each web is at least as long as the inner part axial length.

12. A bush according to any preceding claim, wherein the webs are disposed in an arrangement that in cross-section has one axis of symmetry.

13. A bush according to any preceding claim, wherein the webs are disposed in an arrangement that in cross-section has two axes of symmetry.

14. A bush according to any preceding claim, wherein the radial thickness of inner part is greater than the radial thickness of the outer part.

15. A bush according to any preceding claim, wherein the bush is a single unitary piece of metal.

16. A bush according to claim 15, wherein the metal is an extrudable alloy.

17. A bush according to claim 16, wherein the metal is an aluminium alloy.

18. A bush according to any of claims 1 to 14, wherein the bush is unitarily formed from a composite material.

19. A suspension assembly for a vehicle, the suspension assembly comprising:

a suspension component; and a bush as claimed in any preceding claim, wherein the suspension component and bush are configured so as to be retainable in association with one another.

20. A suspension assembly according to claim 19, wherein the suspension component includes an aperture, and the bush is configured to be received in the aperture to permit retention of the suspension component and bush in association with one another.

21. A suspension assembly according to claim 20, wherein the aperture of the suspension component and outer dimensions of the outer part of the bush are sized such that an interference fit is provided therebetween.

22. A suspension assembly according to claim 21, wherein the aperture of the suspension component is provided with a liner.

23. A vehicle having a suspension assembly as claimed in any of claims 19 to 22.

24. A method of forming a bush for a vehicle, the method comprising:

extruding a bush piece, the bush piece having an outer part with an inner surface, an inner part with an outer surface, the inner part being situated concentrically within the outer part, and at least two webs joining the inner surface of the outer part to the outer surface of

10 the inner part; and cutting the bush piece into at least one bush.

25. A method according to claim 24, comprising the operation of: machining the bush such that the axial length of the inner part is greater than the axial length of the outer part. .

26. A method according to claim 25, wherein cutting the bush piece into at least one bush and machining the bush are performed in a single operation.

Intellectual

Property

Office

Application No: Claims searched:

GB 1706779.4 1-26