Wheel and Tyre Assembly, Method of Manufacture and Use Thereof

Abstract

A wheel assembly and method of forming the same that incorporates a non-pneumatic tyre. The assembly includes a core means forming at least part of a wheel hub and leg members depending from the same, wherein at least part of the leg members are coated and/or over-moulded with at least one polymeric material.

Claims

1. A wheel assembly incorporating a non-pneumatic tyre, said assembly including; a core means forming at least part of the wheel hub and leg members depending from the same, wherein at least part of said leg members are coated and/or over-moulded with at least one polymeric material.

2. The wheel assembly according to claim 1 wherein the core means includes a substantially planar plate or surface forming the hub of the wheel assembly to attach a vehicle axle to the wheel assembly.

3. (canceled)

4. (canceled)

5. The wheel assembly according to claim 1 wherein the leg members are over moulded with a polyurethane or polyurethane based polymer.

6. (canceled)

7. The wheel assembly according to claim 1 wherein the core means is substantially located or formed on a first plane, the leg members are substantially planar and depend or extend from the core means in at least one direction or angle away from the plane of the core means.

8. (canceled)

9. (canceled)

10. The wheel assembly according to claim 7 wherein the leg members depend away from the core means such that at least part of said leg members are at substantially right angles or perpendicular to the core means.

11. The wheel assembly according to claim 5 wherein the polymeric material coating and/or over moulding the core means and/or leg members forms the body of the wheel and/or at least part of the tyre.

12. The wheel assembly according to claim 11 wherein the polymeric material is applied in one or more layers.

13. The wheel assembly according to claim 12 wherein the density and/or rigidity properties of the polymeric material layers are different.

14. The wheel assembly according to claim 13 wherein the polymeric material can form one or more bands around the edge or towards the outer surface, or tread, of the tyre in contact with the ground in use.

15. The wheel assembly according to claim 14 wherein the polymeric material includes at least one ring or layer of less dense or foamed polyurethane.

16. The wheel assembly according to claim 2 wherein the core means and/or leg members are formed from steel, stainless steel or nylon.

17. (canceled)

18. (canceled)

19. (canceled)

20. (canceled)

21. The wheel assembly according to claim 16 wherein the entire core means is coated or over moulded with polymeric material, thereby protecting the wheel hub formed by the central portion of the core means.

22. (canceled)

23. A method of producing or manufacturing a wheel and tyre assembly, said wheel and tyre assembly including a core means forming at least part of the wheel hub and leg members depending from the same, wherein said method includes the step of coating and/or over-moulding at least part of said leg members with at least one polymeric material.

24. The method according to claim 23 wherein the polymeric material provides a base or support, and/or forms a body of the tyre.

25. The method according to claim 23 wherein the core means is formed from a cut blank.

26. The method according to claim 25 wherein the leg members are bent from a planar blank such that at least part of the leg members do not lie in substantially a same plane as the core means.

27. The method according to claim 25 wherein the leg members are formed or bent such that at least part of the leg member surface is at right angles to the surface of the core means.

28. The method according to claim 25 wherein the core means includes a plurality of leg means extending from the edge or radius of the same.

29. The method according to claim 28 wherein adjacent or alternating leg members extend in substantially opposite directions to each other.

Description

[0038] Specific embodiments of the invention are now described with reference to the following figures wherein;

[0039] FIG. 1 shows core of the wheel and tyre assembly in accordance with one embodiment of the invention;

[0040] FIGS. 2a and 2b shows the wheel and tyre assembly with the polymeric coating applied in accordance with an embodiment of the invention; and

[0041] FIG. 3 shows an embodiment of a wheel and tyre assembly in accordance with one embodiment of the invention with a hard outer tread layer and a softer intermediate layer;

[0042] The present invention provides an apparatus and method for producing such an apparatus being a multi-purpose, puncture-proof wheel & tyre assembly.

[0043] The wheel can be made from many suitable materials relevant to the desired application. FIG. 1 shows steel blank or core 2 that is pre-cut and then formed to create support legs 4.

[0044] The blank or core 2 can be painted, e-coated or primed with suitable surface treatment for the given application. It is then over-moulded with a suitable polymer 6, as shown in FIG. 2, to create an interface for the steel blank and the tyre.

[0045] In this example the steel blank 2 is e-coated for corrosion resistance with a material that will bond to a polyurethane coating during the moulding cycle.

[0046] This polyurethane coating 6 will have suitable strength and stiffness to create the desired wheel rim. Bonding to the e-coat improves overall strength and durability. The steel blank can also be coated with the polyurethane to create a protective layer against stone impacts and the like and corrosion.

[0047] The steel blank is unique in its method of construction and is efficient in material use by minimising scrap and offcuts.

[0048] Importantly it removes the need for welding or bolting rim halves together which is current common practice.

[0049] The structural polyurethane layer 6 can be bonded further layers to form the wheel and tyre assembly, or can be moulded into a suitable shape to form a tread and even a shape to accept a pneumatic tyre if desired.

[0050] The use of polyurethane has an advantage in that polyurethane outer can be build-up as many layers as desired for the given application giving unlimited variation in load deflection performance. Layers can be made from various hardness's and densities as polyurethane can be moulded in a range of solid hardness's and a range of micro-cellular hardness's and densities.

[0051] In addition by using polyurethane we can also vary the base compounds to either provide rebound or shock absorption as required, or combine them for complex requirements.

[0052] During the moulding cycle and by using thermoset polyurethane, each layer can be chemically bonded together providing very reliable, repeatable and tough bonds. This removes the need for adhesives between the polymer layers as is required in other applications.

[0053] In the example given in FIG. 3, an intermediate foamed polyurethane layer 8 is incorporated which lies underneath a harder and denser outer polyurethane tread layer 10.

[0054] The skilled person will appreciate that using polymeric coatings, hub caps and other such items can be over-moulded and secured in-place as required.

[0055] Further, usually for heavy applications one or more cores 2 or centre discs can be combined to increase strength. This combination can also be used for aesthetics as required. If more than one core is used they can be pre-welded, screwed together and/or rely on the bond of the intermediate polyurethane layer, whichever is required for the application.

[0056] The skilled person will appreciate that the leg off-set shown in FIG. 1 can be achieved by cutting the blank and bending the legs in opposite directions, or by using two or more centre discs or cores and bending the legs in the same direction as required.

[0057] A further environmental advantage is that at the end of life the centre discs or cores 2 can be recovered and re-used by removing the remaining urethane: if burning is used, energy from this process can be salvaged or recovered. Polyurethane can also be removed mechanically and/or chemically.

[0058] If the centre discs are cut and formed from spring steel, the legs can be formed to create springs which can work in conjunction with layer or layers of polyurethane. These legs can also be used to transfer heat away from the centre of the polyurethane, to prevent it over-heating during high speed operation; which is a known problem. The size and shape of the formed steel “legs” can be optimised to remove as much heat as possible. This can be combined with features on the tyre and or wheel and or hub to encourage air-flow to the steel or other metal insert (which is known technology), to remove heat As shown in FIG. 2b.