WO2000007832A1

WO2000007832A1 - Safety device for a wheel rim

Info

Publication number: WO2000007832A1
Application number: PCT/IB1999/001402
Authority: WO
Inventors: Anthony Edward Paterson; Ian Douglas Paterson; Michael Francis John Jackson; Andre Jacobs
Original assignee: Aluminium Federation Of Southern Africa; Bma Marketing Services (Proprietary) Limited
Priority date: 1998-08-06
Filing date: 1999-08-06
Publication date: 2000-02-17
Also published as: AU5297199A

Abstract

A safety device (10) in the form of a band-type cover for the well of a wheel rim is provided. The device consists of a pair of half bands (12a, 12b) fastened to one another by a pair of sinuous clips arranged to clip onto pins support by respective flanges on the half bands. In the event of a loss of air pressure in the tyre due to a blow-out or puncture, the cover prevents the beading of the tyre falling into the well. As a result, the tyre (42) remains on the rim (34), even during heavy braking.

Description

SAFETY DEVICE FOR A WHEEL RIM

BACKGROUND OF THE INVENTION

THIS invention relates to a safety device which covers the well in the hub of a wheel and to a fastening device which is particularly suitable for fastening the safety device to the wheel.

Pneumatic tyres are generally mounted on a wheel which comprises a hub having two flanges extending therefrom and a wheel well located between the flanges. When the tyre is inflated the internal air pressure forces the beads of the tyre against the flanges, thereby securing the tyre to the rim.

The bead of the tyre has an internal diameter less than the outside diameter of the wheel and the well is provided to enable the tyre to be fitted on to the wheel. When there is loss of air pressure in the tyre due to a blow-out or puncture, the beading may move away from the flanges and fall into the wheel well. This exposes the metal flange to the road causing loss of traction and causing the driver to lose control of the vehicle.

In the past, removable band-type well covers have been fitted to the wheel, after a tyre has been fitted on the wheel. In the event of deflation of the tyre, the cover stops the beading of the tyre from falling into the well. With the cover in place, the tyre will remain on the wheel, even during heavy braking.

CWRMAϊtGN COPY Bands known in the prior art are held on to the wheel under tension by threaded fastening means such as bolts and nuts (see for example US 4.122,882. US 4.391 ,317, US 4.784.202 and US 4,694,874). A problem with such threaded fastening means is that the bolts can loosen over time, causing the band to become loose. Another problem is that it is difficult to fit the threaded fastening means and they are also expensive to manufacture. Also, the bolts and nuts can be replaced with nuts and bolts lying around a workshop which may not be suited to the application and can lead to the band becoming loose during operation. A loose band within the tyre is dangerous and is useless in the case of a puncture.

SUMMARY OF THE INVENTION

According to the invention there is provided a safety device for use with a vehicle wheel of the type having a hub, two rims extending from the hub, and a wheel well located between the rims, the safety device comprising:

an annular band shaped to fit about the well and seat thereon, the band having first and second free ends;

at least one continuous retaining formation which extends along the inner surface of the band and is integral therewith, for preventing movement of the band relative to the wheel; and

fastening means arranged to connect the first and second free ends and to tension the band.

The band may comprise at least two part-annular components arranged to be connected together to define the annular band. The height of the at least one retaining formation is preferably approximately equal to the depth of the well.

Advantageously, the at least one retaining formation comprises two flanges, each flange being spaced inwardly from a respective edge of the band.

The two flanges may be joined by a web.

The flanges preferably extend radially from the band.

The band is preferably an extrusion, more preferably a metal extrusion.

The metal is typically an alloy such as aluminium.

The fastening means is preferably flexible and resilient.

Preferably, the flexible and resilient fastening means comprises:

a clip having a first end connectable to the first free end of the band;

a second end which is arranged to engage releasably with the second free end of the band; and

a flexible and resilient body portion between the first and second ends.

According to another aspect of the invention there is provided a fastening clip for fastening a first object and a second object to one another, the clip comprising: a first formation connectable to the first object;

a second formation arranged to engage releasably with the second object; and

a flexible and resilient body portion between the first and second formations and formed integrally therewith, the body portion being sinuous in shape.

Typically, the first formation is connectable to a first pin located on the first object and the second formation is arranged to engage releasably with a second pin located on the second object.

The first and second objects are typically the free ends of the annular band defined above.

The first and second pins are conveniently supported between the spaced apart flanges at the free ends of the annular bands defined above.

Advantageously, the clip is arcuate in shape, and preferably follows the same arc as the annular band defined above.

The sinuous strip may have from three to eight opposed curves, typically five opposed curves.

The clip is preferably an extrusion, more preferably a metal extrusion.

The metal is typically an alloy such as aluminium. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 Is a pictorial view of a safety device according to the invention;

Figure 2 Is a cross-sectional view of a safety device according to the invention attached to a wheel;

Figure 3 Is a cross-sectional view of a safety device according to a second embodiment of the invention;

Figure 4 Is a cross-sectional side view of Figure 1 along the line 4-4;

Figure 5 Is a pictorial view of a fastening device according to the invention; and

Figure 6 Is a cross-sectional view of Figure 5 along the line 6-6.

DESCRIPTION OF EMBODIMENTS

Referring to Figure 1 , a safety device 10 according to the invention, comprises two half bands 12A and 12B each of which has two equally spaced flanges 14 and 16 extending radially from the inner surface 18 of the half band. The half band and flanges are formed integrally, being extruded from aluminium in a plastic state. Although aluminium is preferred, the bands and clips could be made from other materials including other alloys, steel or carbon fibre for example. Each half band 12A and 12B has two free ends 20 and 22 respectively. The half bands 12A and 12B are fastened to one another by fastening means in the form of clips 24 and 26 to form an annular band. The clips 24 and 26 are similar and connect to (referring to clip 26) aluminium (or steel) pins 30 and 32 that are supported between the flanges 14 and 16 at the free ends 20 and 22 of the bands 12A and 12B, respectively.

Figure 2 shows a half band 12 of the safety device 10 attached to a wheel 34. The wheel 34 has flanges 36 and 38 extending from a hub 39 and a well 40 located between the flanges. A pneumatic tyre 42 is fitted to the rim 34 with the beads 44 of the tyre secured against the rim flanges 36 and 38. The band 10 is held in the well, under tension, by way of the fasteners 24 and 26 (not shown). The height of the flanges 14 and 16 is approximately equal to the depth of the well 40 so that the ends of the flanges engage the base of the well frictionally and prevent undesirable rotational and/or axial movement of the band relative to the well. The top surface 41 of the band 12 covers and lies substantially flush with the opening to the well 40.

Referring back to Figure 1 , the end of each band is cut-away at point 33. to provide space for the wheel's valve (not shown) which is generally located in the well.

Referring to Figure 3 in this embodiment, the flanges 14 and 16 of the band 12 are joined by a web 45, to provide a relatively wide, continuous retaining formation. This arrangement is typically be for heavy duty applications, for example for the rims of truck wheels. Referring to Figures 4 and 5. the clip 26 has a first end 46 which is connected to the pin 32. a second end 48 which releasably engages with the pin 30. The clip 26 also has a sinuously shaped body portion 50. The sinuous body portion comprises five opposed curves 52 and 54 which are joined by walls 56. Because of its sinuous shape, the body portion 50 is flexible and resilient, allowing the clip to flex longitudinally. The clip 26 also has an arcuate side profile which follows substantially the same arc as the bands 12A and 12B. The pins 30 and 32 are located at positions on the flanges that ensure that the clip does not extend substantially above the outside surface of the band.

The releasable end 48 of the clip 26 has a recess 58 which receives the pin 30. An inclined follower surface 60 is provided adjacent the recess 58 for attaching the end 48 to the pin 30. Generally, the fastener is attached to the band by merely tapping it with a hammer. Alternatively, the band may be tensioned on the rim by pulling the ends thereof together with a tensioning tool which engages with an aperture (not shown) formed on each free end 20 and 22 of the bands 12A and 12B and the clip can be tapped in to place with a hammer. The releasable end 48 is also provided with a projection 62 for conveniently disengaging the clip from the pin 30 by prying it off with a screwdriver.

Referring to Figure 6, the arcuate shape of the clip 26 is shown by the dotted lines E-E. The curves 52 and 54 have a thickness of about 4mm and the walls 56 a thickness of about 3mm. The clip 26 has a substantially even stress distribution along the body portion 50 thereof to allow for elongation of the body portion and maximum retaining stress to hold the band 12 under tension against the rim. In the present example, the clip is made

extruding a 6000mm length from 6082 or 6061 alloy aluminium having the profile described above. The extrusion is heat treated to the T6 condition and cut to size normal to the plane of the extrusion. The size to which the clip is cut depends on the application the clip is to be used in. In the case of motor car rims, the clip is cut to a width of approximately 15mm. For heavy duty applications, in the case of truck rims, the clip is cut to a width of approximately 25mm.

Conventionally, aluminium would not be the first choice of material for a flexible and resilient clip fastener of the general kind in question. However, by forming the clip with multiple curves as described above, when under tension, the clip deforms elastically and not plastically.

Embodiments of the fastening device (clip) of the invention were tested with a calibrated Hunsfield tensometer. In each case, the clip was subjected to tension on a curved block that simulates the curvature of a wheel well. The results of tests conducted on fastening devices with widths of 12. 15 and 25mm are set out in the Table below:

The tests show that in practice there is sufficient tension in the clips to achieve the purpose of the clips, i.e. to hold the annular bands securely in the wheel well, without failure during normal use.

The "load failure'^' shows the load (in tons) which may be applied to anodised, non-anodised and bead blasted clips of 12. 15 and 25mm in width, before the clip breaks. It will be noted that the wider the clip the higher the load it can withstand. It is also noted that the non-anodised clips could withstand a higher load than the anodised clips.

The "extension to failure" shows the distance to which the clips can be extended before prominent plastic extension takes place (at tensile rupture). The narrower clips have a greater extension before they fail.

Although aluminium is preferred, it is envisaged that the clip and band of the invention may be made from other materials including steel, other alloys or carbon fibre.

The safety device 10 of the present invention is advantageous over known devices in that the flanges 14 and 16 of the annular bands provide a relatively large surface area of the band in contact with the well to help prevent the band from slipping (longitudinally and axially) within the well during use. Another advantage of the flanges is that they serve to support the band to help prevent it being crushed into the well when it comes into contact with the bead of a tyre during a blow out. The annular bands are also conveniently made by extruding aluminium. Because of the unique fastening means, the safety device 10 is relatively easy to install Once the band has been placed within the tyre well, the engaging end of the fastener need merely be tapped on to the corresponding pin in order to fasten and attach the band in the well. Furthermore, the fastener is relatively inexpensive to manufacture, difficult to copy as specialised equipment is required to make it and difficult to replace with inferior parts that may be found lying around in a workshop.

Lastly, the atmosphere within a pneumatic tyre is corrosive and the aluminium bands and clips are resistant to corrosion.

Claims

A safety device for use with a vehicle wheel of the type having a hub, two rims extending from the hub and a wheel well located between the rims, the safety device comprising:

A safety device according to claim 1 wherein the band comprises at least two part-annular components arranged to be connected together to define the annular band.

A safety device according to claim 1 or 2 wherein the height of the at least one retaining formation is approximately equal to the depth of the well.

A safety device according to any one of the preceding claims wherein the at least one retaining formation comprises two flanges each spaced inwardly from a respective edge of the band.

5. A safety device according to claim 4 or 5 wherein the two flanges are be joined by a web.

6. A safety device according to claim 4 or 5 wherein the flanges extend radially from the band.

7. A safety device according to any one of the preceding claims wherein the band is an extrusion.

8. A safety device according to claim 7 wherein the band is a metal extrusion.

9. A safety device according to claim 8 wherein the metal is an alloy.

10. A safety device according to claim 9 wherein the alloy is aluminium.

1 1. A safety device according to any one of the preceding claims wherein the fastening means is flexible and resilient.

12. A safety device according to claim 1 1 wherein the flexible and resilient fastening means comprises:

a clip having a first end connectable to the first free end of the band;

a second end which is arranged to engage releasably with the second free end of the band: and a flexible and resilient body portion between the first and second ends.

13. A fastening clip for fastening a first object and a second object to one another, the clip comprising:

a first formation connectable to the first object;

a second formation arranged to engage releasably with the second object; and

14. A fastening clip according to claim 13 wherein the first formation is connectable to a first pin located on the first object and the second formation is arranged to engage releasably with a second pin located on the second object.

15. A fastening clip according to claim 13 wherein the first and second objects are the free ends of the annular band defined in any one of claims 1 to 10.

16. A fastening clip according to claim 15 wherein the first and second pins are supported between the spaced apart flanges at the free ends of the annular bands.

17. A fastening clip according to any one of claims 13 to 16, wherein the clip is arcuate in shape.

18. A fastening clip according to claim 16 wherein the clip is arcuate in shape and follows the same arc as the annular band.

19. A fastening clip according to any one of claims 13 to 18 wherein the sinuous strip has from three to eight opposed curves.

20. A fastening clip according to claim 19 wherein the sinuous strip has five opposed curves.

21. A fastening clip according to any one of claims 13 to 18 wherein the clip is an extrusion.

22. A fastening clip according to claim 21 wherein the clip is a metal extrusion.

23. A fastening clip according to claim 22 wherein the metal is an alloy.

24. A fastening clip according to claim 23 wherein the alloy is aluminium.