Patent Description:
It is known to provide automobile alloy wheels with a decorative, typically plastic, trim; particularly along or between the wheel spokes. These inserts may be coloured to match the automobile body paint, or to complement it.

Such trim may have a functional as well as a decorative purpose. In one arrangement, in an attempt to improve vehicle efficiency, it is proposed to use light alloy spoked wheels with relatively thin spokes in order to reduce wheel mass. This leads to a very open wheel structure which is not favourable for good aerodynamic performance. So, it is further proposed to fill the spaces between the spokes with a lightweight plastic trim, also known as an insert.

Such trim is conveniently clipped to the wheel so that no fastening means are visible, but existing fastening arrangements have proven unreliable; leading to loss of inserts. A more secure fastening arrangement is therefore required. It is known to employ fasteners which pass through an aperture in a wheel, but it can be difficult to obtain a secure fastening whilst accommodating tolerances in the thickness of the wheel.

Wheel trim components also need to be removable to enable them to be replaced in the event of damage, such as when a wheel is "kerbed"; while the wheel and trim assembly should remain aesthetically pleasing. Likewise, trim components may need to be transferred to a replacement wheel; so that they are compatible with those on the other wheels on a vehicle to which the replacement wheel is to be fitted.

Prior art patent application <CIT> discloses an alloy road wheel with a cladding secured to the wheel by mushroom head expansion clips secured to the wheel by cross head screws.

It is an object of embodiments of the present invention to provide an improved arrangement for fastening trim to a vehicle wheel which overcomes or at least mitigates problems associated with known arrangements.

According to an aspect of the present invention there is provided a road vehicle wheel trim system comprising the features of claim <NUM>.

Since the male fitting can be retained within the female fitting over a range of relative positions, the system can securely fasten the trim component to a wheel whilst accommodating a range of wheel thicknesses. This leads to more securely fastened trim components.

The system also facilitates an arrangement where the fitting on a trim component is provided on its rear face and is introduced into a through-hole on the front face of a wheel, and the retainer is introduced into the same through hole from the rear of the wheel. This enables a discreet installation to be achieved where neither fitting nor retainer is visible in normal use of the wheel.

Of course, since the invention allows trim components to be more securely fastened, and more discreetly installed, manufacturers are more likely to install them. In consequence, the environmental benefits of including trim components that improve efficiency are more likely to be achieved.

The removability of the head from the retainer enables a trim component to be removed from a wheel, for example so that a damaged component can be replaced. The head may be arranged to be broken off from the retainer. The retainer may comprise a frangible portion to facilitate this. The head may comprise one or more slots or formations intended to receive a tool, such as a screwdriver, to facilitate removal of the head. The head may take the form of a flange, and a slot may be formed in an outside edge of the flange.

The retainer may define a generally cylindrical cavity.

The retainer may comprise two or more separate components which, together, may define the female fitting. This can facilitate moulding of the retainer.

The retainer comprises two or more hingedly connected components which, together, define the female fitting. This facilitates production, enabling the retainer to be moulded in one piece in an as moulded configuration; and later put into an in use configuration (in which it would be more difficult or impossible to mould the retainer).

The retainer may be moulded in a single piece. The retainer may be moulded from a plastic material.

Both the male fitting and the female fitting comprise multiple rows of teeth arranged to engage with each other when the male fitting is received into the female fitting. The more teeth that are engaged, the more securely the two fittings are fastened together. The teeth of the male and/or female fitting may interlock with the other fitting, enabling insertion of the male fitting into the female fitting; but preventing its removal without destroying the female fitting.

Conveniently, the male and/or female fittings are fir tree fittings.

The fitting of the trim component may be formed integrally, for example moulded with, the trim component. Or it could be formed separately and fastened to the trim component. The trim component may comprise an arm. The male fitting comprised in the component may be disposed on the arm.

There may be multiple trim components as dictated by the design of a wheel.

The or each trim component may comprise multiple fittings. A respective retainer may be provided for each fitting. Increasing the number of fasteners or retainers and fittings per trim component increases the security with which the trim component may be fastened to a wheel.

According to a second aspect of the present invention there is provided a road vehicle wheel assembly comprising:.

The wheel may comprise for example <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or more spokes. A plurality of trim components may be provided. Where the wheel is spoked, a respective trim component may be provided to fill some or all of the spaces between the spokes. Alternatively, or in addition, a respective trim component may be provided to fit over some or all of the spokes.

In a spoked wheel, respective through-holes may be located at or adjacent a radially inner and/or a radially outer end of each spoke. Single respective through-holes may be located between each adjacent pair of spokes in or adjacent a radially inner position. Two further through-holes may be located between each adjacent pair of spokes at a radially outer position, one adjacent each spoke. A respective through-hole may be located in each spoke towards a radially outer end of the spoke. Alternatively, or in addition, a respective through-hole may be located in each spoke towards the radially inner end of the spoke or in a hub of the wheel adjacent the radially inner end of each spoke.

The wheel may comprise one or more recesses. In this case, a through-hole may be formed in the or each recess; and a trim component may be configured to fit into each recess. In a spoked wheel, recesses may formed in one or more of the spokes.

In a spoked wheel, a plurality of trim components may be arranged to fill spaces in or between the spokes.

The wheel may comprise one or more webs. One or more through-holes may be formed in the webs.

The wheel may have an outer (or front) face, which is visible when fitted to a vehicle and an inner (or rear) face which faces the wheel suspension when the wheel is fitted to a vehicle. The or each trim component is fitted to the front face of the wheel.

The or each trim component may have an outside (or front) face intended to be visible in use and an opposite, inside (or rear) face which faces the wheel suspension when the trim component is fitted to the wheel and the wheel is fitted to a vehicle. The or each fitting of the trim component is disposed on the rear face of the trim component. The or each fitting of the trim component will be hidden when the trim component is visible from the outside face. The trim component may take the form of a sheet of material. The or each fitting may be formed on the inside face of the sheet of material. The structure may comprise an arm. The sheet may be flat or curved (depending on the design of the wheel to which it is to be fitted).

The present invention also provides a road vehicle such as an automobile or van fitted with one or more wheel assemblies according to the invention. The road vehicle may be an electric vehicle.

In order that the invention may be more clearly understood, embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:.

(It should be noted that the outside face of the wheel depicted in <FIG> has the same styling as some wheels which are prior art to this patent; but the structures of the wheel and of the trim components according to the invention differ to the prior art.

Referring to the drawings, <FIG> show a light alloy road wheel <NUM> for an automobile. In this example the wheel is cast from an aluminium alloy. The wheel could, however, be manufactured from other suitable materials such as a magnesium or other non-ferrous alloy, and using any suitable technique, e.g. forging or the like.

<FIG> shows the outside face of the wheel, being the face that faces away from a vehicle to which it is fitted and which is visible in use. <FIG> shows the opposite, inside/rear, face of the wheel.

The wheel has five forked spokes <NUM>, each extending from a central hub <NUM> to a rim <NUM>. In use, the rim will be fitted with a pneumatic tyre (not shown).

A single trim component <NUM>, in the form of an insert, is shown fitted to the wheel <NUM>. The trim component <NUM> comprises a sheet of plastics material <NUM> which substantially fills an opening in the wheel defined between two adjacent spokes <NUM> and the rim <NUM> of the wheel. The trim component <NUM> has an outer face, visible in <FIG>, which presents a smooth, generally flat surface on the outside face of the wheel, and lies flush with, or slightly recessed behind, the outside face of the spokes <NUM> and the wheel rim <NUM>. The trim component <NUM> also has an opposite inner (rear) face visible in <FIG> and <FIG>.

Only one trim component <NUM> is shown fitted to the wheel <NUM>. It will be appreciated, however, that in use five trim components would be fitted in order to close all the spaces between adjacent pairs of spokes <NUM>. Suitably sized and shaped trim components could also be fitted into each spoke to close the spaces between the two prongs of each forked spoke <NUM>. Care should be taken to allow passage of air through the wheels to allow brake cooling.

By closing openings in the wheel, fitting trim components <NUM> improves the aerodynamic performance of a vehicle fitted with the wheel.

At the points where each spoke <NUM> joins the wheel hub <NUM> and rim <NUM>, a web 6is, 6os of material formed integrally with the wheel extends between the spoke and the hub (6is) or rim (6os) and presents a substantially planar face towards the outside of the wheel <NUM>. A circular through-hole 7is, 7os extends through each web 6is, 6os generally at right angles to the outside face of the web 6is, 6os. These webs and holes are particularly suitable for mounting inserts between the two prongs of a spoke <NUM>; but it can be seen from <FIG> that other webs and holes may be cast into the wheel for fitting of inserts <NUM> between spokes, for example webs 6i and 6o and holes 7i and 7o in <FIG>.

The trim component <NUM> comprises a moulded sheet <NUM> of plastics material (such as ABS (Acrylonitrile Butadiene Styrene) with an outline shape generally of that of a sector of a circle, but with curved corners, so that it fills the space formed between adjacent spokes <NUM> and the rim <NUM> of the wheel <NUM> (<FIG>). The outside face of the sheet <NUM> is smooth and generally flat.

On the inside face of the sheet <NUM> a respective male fitting <NUM> is disposed at each corner of the sheet <NUM>. In this embodiment the male fitting comprises an elongate fir tree structure formed by an elongate shaft encircled by three circumferential teeth <NUM> spaced axially along the shaft towards a free end. Each tooth <NUM> presents a wedge-shaped profile towards the free end of the fitting, so that the diameter of the fitting decreases towards its free end along each tooth and then abruptly increases at the next tooth. The male fittings <NUM> are moulded from a resiliently flexible plastic material. The male fittings extend generally at right angles from the rear face of the sheet <NUM>. The male fittings <NUM> are positioned to be received into through-holes 7i and 7o when the fitting <NUM> is mounted to the wheel <NUM>.

Referring now to <FIG> there is shown another spoked, light alloy road wheel <NUM> for a vehicle. The wheel has five pairs of adjacent spokes <NUM>, <NUM>, each extending from a central hub <NUM> to a rim <NUM>. In use the rim will be fitted with a pneumatic tyre (not shown).

One spoke <NUM> of each pair defines an elongate recess <NUM> in a front face of the spoke. The recess extends along the length of the spoke from the wheel rim <NUM> to the hub <NUM> and continues in the hub, curving towards the adjacent spoke <NUM> of the pair.

Two through-holes are formed in each recess <NUM> of the wheel, one 27os is formed toward the radially outer end of the spoke <NUM> in which the recess <NUM> is formed. The other 27is is formed towards the opposite, radially inner, end of the recess <NUM>. Both through-holes are substantially circular in cross-section.

As shown in <FIG>, a respective trim component <NUM>, in the form of an insert, is fitted to each recess <NUM> of the wheel. The trim component <NUM> comprises a moulded sheet (<NUM>, <FIG>) of plastics material with an outline shape that substantially fills the recess <NUM>. The trim component has an outer face, visible in <FIG>, with a smooth, generally flat, surface. The trim component <NUM> has an inner face, visible in <FIG>, with a generally flat inner surface surrounded by a perimeter wall. The height of the wall defines the thickness of the sheet, and this is such that the outer surface is slightly recessed behind the face of the wheel surrounding the recess <NUM> when the trim component <NUM> is fitted to the recess.

On the inside face of the sheet <NUM> a respective male fitting 30is and 30os is disposed at each opposite end of the sheet <NUM>. In this embodiment the male fittings comprise an elongate fir tree structure, of the same design as the fittings <NUM> shown in <FIG>. One fitting 30is (the inner fitting) is positioned to be received into the radially inner through-hole 27is in the recess <NUM>, and the other fitting 30os (the outer fitting) is positioned and shaped to be received into the corresponding radially outer through-hole 27os in the recess <NUM> when the fitting <NUM> is mounted to the wheel <NUM>.

Referring to <FIG> and <FIG> there is shown a retainer <NUM> for use with both the trim components of <FIG> and <FIG> in an as moulded configuration. The retainer is arranged to define a female fitting for receiving and retaining the male fittings <NUM>, 30is, 30os of the trim components. The retainer <NUM> is moulded in one piece from a resilient plastic material. The retainer comprises two adjacent substantially semi-cylindrical halves <NUM> joined by live hinges <NUM>. Three axially spaced teeth (<NUM>, <FIG>) are formed around the concave surface of each semi cylindrical half. The teeth are sized and spaced substantially identically to the teeth <NUM> of the male fitting <NUM>, 30is, 30os. At one end of the retainer moulding a flange <NUM> is formed. A slot (<NUM>, <FIG>) is formed in the outside circumferential edge of the flange of each semi-cylindrical half of the fitting. A resilient locking catch <NUM> is formed on a lateral edge of one of the semi-cylindrical halves.

In use the two semi-cylindrical halves of the retainer <NUM> are folded together to form a generally cylindrical fitting. At one end of the fitting there is a projecting flange <NUM> forming a head. At the other end there is an opening which opens into a generally cylindrical cavity with internally projecting circumferential, axially spaced teeth <NUM>. In the in use configuration, the catch <NUM> on one half captures the other half to retain the moulding in this configuration.

The retainer <NUM> is sized so that in its in use configuration the cylindrical portion can be inserted into a cylindrical through-hole 7is, 7os, 7i, 7o, 27is, 27os in a wheel, but the head of the retainer cannot. The length of the retainer and dimensions of an aperture through a wheel are chosen so that when the cylindrical part is fully inserted into the through-hole, such that the head of the retainer abuts the wheel, the cylindrical part of the retainer is contained within the through-hole in the wheel. The retainer <NUM> is also sized such that in its in use configuration the internal diameter of the cylindrical portion (excluding the teeth) is the same or ever so slightly larger than the external diameter of the male fittings (including their teeth).

In use to affix a trim component <NUM>, <NUM> to a wheel, retainers <NUM>, in their operative configuration, are introduced into through-holes 7is, 7os, 7i, 7o, 27is, 27os in the rear face of a wheel <NUM>, <NUM> and male fittings <NUM>, 30is, 30os on the trim components <NUM>, <NUM> are introduced into the through-holes from the front face of the wheel. The trim components <NUM>, <NUM> and retainers <NUM> are urged together so that the male fittings on the trim components are received into the cylindrical cavities defined by the retainers. Owing to the relative sizes of the fittings and the retainers, this causes their respective teeth to ride over one another; locking the fittings to the retainers such that the wheel is clamped between the trim component and the retainers, securing the trim component to the wheel. As both the fittings and retainers have three axially spaced teeth, the fittings can be captured by the retainers at multiple different depths of insertion of one into the other, accommodating variations in thickness of the wheel in which a through-hole is formed.

To remove a trim component from a wheel a tool, such as a screwdriver, is inserted into the slots <NUM> in the flanges <NUM> on the retainer and used to snap the flanges off the retainer <NUM>. The tool can also be used to break bridge pieces forming hinges <NUM>, allowing the retainer <NUM> to become to a degree collapsible. This may allow the two parts of the retainer to be extracted from the inner face of the wheel; alternatively, the head may now be weakened sufficiently that the remainder of the retainer <NUM> can then be withdrawn, with the fitting to which it is fastened, out of the front face of the through-hole in the wheel. Once withdrawn, the two halves of the retainer can be unclipped and separated and the retainer <NUM> removed from the fitting <NUM>, 30is, 30os. The parts of the retainer are discarded and a fresh retainer used to refit the fitting or a replacement fitting.

Claim 1:
A road vehicle wheel trim system comprising:
a trim component (<NUM>, <NUM>) for fitment to a road vehicle wheel (<NUM>, <NUM>);
and a retainer (<NUM>) for the trim component;
wherein the trim component (<NUM>, <NUM>) comprises a male (<NUM>, <NUM>) fitting and the retainer (<NUM>) is arranged, in use, to be at least partially disposed in a through-hole (<NUM>, <NUM>) in the wheel to define a female fitting for engaging with the fitting of the trim component (<NUM>, <NUM>);
and wherein the retainer (<NUM>) comprises a body (<NUM>) intended in use to be at least partially disposed in the through-hole (<NUM>, <NUM>) in the wheel and to define a female fitting; and a head (<NUM>) which is sized to prevent it passing into the through-hole;
characterized in that:
the male (<NUM>, <NUM>) fitting and the female fitting comprise multiple <NUM> rows of teeth spaced along their lengths for engaging with the other of the two fittings so that the male (<NUM>, <NUM>) fitting can be, in use, retained within the female fitting over a range of relative positions of the two fittings; and wherein
at least part of the head (<NUM>) is arranged to be removable from the retainer (<NUM>) to enable the remainder of the retainer, in use, to pass through the through-hole (<NUM>, <NUM>, <NUM>); and in that:
the retainer is moulded in two halves joined by live hinges, which halves are folded together in use to form a generally cylindrical fitting which is inserted into said cylindrical through-hole in said wheel.