GB2243347A

GB2243347A - Safety tyre arrangement

Info

Publication number: GB2243347A
Application number: GB9106580A
Authority: GB
Inventors: Hamid Suliman Mirza
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-04-03
Filing date: 1991-03-27
Publication date: 1991-10-30
Anticipated expiration: 2011-03-27
Also published as: GB9106580D0; GB9007425D0; GB2243347B

Abstract

A safety tyre arrangement, which comprises a main tyre 14 mounted on a wheel 10 and a safety tyre 16, also mounted on the wheel 10 or an adjacent wheel (Figs 5 and 9). The safety tyre 16 is mounted in such a manner that it remains unused unless and until the main tyre 14 fails. The safety tyre may be a solid ring of plastics or rubber or may be an uninflated pneumatic tyre connected to a cylinder 24 of compressed gas via a valve 20 actuated by a trigger 22 when pressure in the main tyre falls. <IMAGE>

Description

Safetv tyre arrangement This invention relates to a safety tyre arrangement.

Vehicle tyres used today consist of pneumatic rubber tyres mounted on metal wheels. When such a pneumatic tyre fails, the vehicle comes to rest on the metal rim of the wheel. If such a failure occurs in the form of a blowout when the vehicle is travelling at speed, the driver of the vehicle generally experiences considerable difficulty in keeping control of the vehicle owing to the lack of traction afforded by the rim of the wheel.

The present invention seeks to improve the probability of the driver retaining control of the vehicle in such circumstances.

Accordingly, the present invention is directed to a safety tyre arrangement, which comprises a main tyre mounted on a wheel and a safety tyre also mounted on the wheel in such a manner that the safety tyre remains unused unless and until the main tyre fails.

The safety tyre may comprise an uninflated pneumatic tyre connected to a cylinder of compressed gas.

A trigger device is in this case arranged to be activated by failure of the main tyre. Upon such failure, therefore, the safety tyre is inflated by gas from the gas cylinder.

One advantageous construction has the safety tyre placed inside a. standard tyre so that a wide rimmed wheel is not required and the safety tyre, being wholly within the interior of the standard tyre, and having an outer perimeter spaced from the inside of the roadadhering part of the standard tyre, is protected from damage whilst the standard tyre is undamaged and in use.

However the safety tyre may alternatively comprise a solid rubber or plastics ring placed, for example, alongside or within the main tyre. The ring has a smaller external diameter than the main tyre so that it only comes into contact with the ground when the main tyre fails.

The present invention also extends to a vehicle equipped with at least one tyred safety wheel mounted adjacent to a tyred main wheel of the vehicle, in which the lower most point of the tyre of the safety wheel is higher than that of the tyre of the main wheel so that the tyre of the safety wheel does not touch the ground unless and until the tyre of the main wheel fails.

Examples of safety tyre arrangements made in accordance with the present invention are shown in the accompanying drawings, in which Figures 1 to 3 show respective diagrammatic cross-sections on the diameters of three different such arrangements; Figure 4 shows an exploded side view of the arrangement illustrated in Figure 1; Figure 5 shows a diagrammatic front view of a further possible arrangement in accordance with the present invention; Figure 6 shows a perspective diagrammatic view of the arrangement illustrated in Figure 1 shown in greater detail; Figure 7 shows a perspective diagrammatic view of the arrangement illustrated in Figure 2 shown in greater detail; Figure 8 shows a perspective diagrammatic exploded view of the arrangement illustrated in Figure 3 shown in greater detail; and Figure 9 shows a perspective exploded view of the arrangement illustrated in part of Figure 5.

With reference to Figures 1 and 6 a metal wheel 10 for a motor vehicle has a rim 12, which is wider than that of a conventional rim. As with a conventional wheel, the rim has a generally U-shaped section, but in addition, the wheel illustrated in Figure 1 has a divider 13 between the outer flanges of the wheel, closer to one of those flanges than it is to the other. As can be seen more clearly in Figure 6, the divider 13 may be constructed by a first flange 13a, a second flange 13b, and a spacer element 13c. The wheel has a conventional pneumatic tyre 14 around its rim 12, between the divider 13 and that flange furthest therefrom. An uninflated pneumatic safety tyre 16 is also fitted around the wheel, but between the divider 13 and the other flange of the wheel rim.A cylinder of compressed gas 24 is attached to an inner wall 10 of the wheel, and is provided with a valve 20 at an outlet of the cylinder. The safety tyre 16 is connected by a tube 18 to the valve 20. The valve 20 in turn is connected to a trigger device 22, for example a pressuresensitive device in the conventional tyre 14. When the main tyre 14 fails, the drop in pressure in its interior releases the trigger 22 which causes the valve 20 to open which in turn causes the safety tyre 16 to inflate.

Figures 2 and 7 show a modification in which the metal wheel 10 has a rim of conventional width, with additional inner flanges 25 to receive the inner lips of the safety tyre 16. Thus the safety tyre 16 is fixed inside the conventional tyre 14. The safety tyre 16 is inflated upon failure of the conventional tyre 14 in the same way as the Figure 1 construction. An advantage of this modification is that the safety tyre 16, being wholly within and spaced from the outer conventional tyre 14, is protected whilst the conventional tyre 14 remains inflated.

In Figures 3 and 8, the rim of the wheel has the same construction as in Figure 1. However, a solid rubber or plastics ring 26 is used instead of a pneumatic safety tyre 16, so that no cylinder 24 or trigger 22 is required.

An outer rim 12 and the ring 26 are held in place by bolts 27 which pass through holes 28 in the rim 12 and the ring 26, and tighten in threaded holes 29 in the divider 13.

Thus, the ring 26 is held in place by the outer rim 12 which is detachable to facilitate ready removal of the ring 26.

Figure 4 further illustrates that the safety tyre 16 is smaller in external diameter than the conventional tyre 14.

The arrangement shown in Figure 5 comprises a vehicle 30 having respective tyred safety wheels 32 positioned coaxially and immediately inwardly of conventional tyred wheels 34 of the vehicle 30. The tyres of the safety wheels 32 have a smaller external diameter than the tyres of the conventional wheels 34, so that one of the tyres of safety wheels 32 only comes into contact with the ground in the event of failure of the tyre of its adjacent conventional wheel 34. As can be seen in Figure 9, the tyre 16 is fitted on and extends around a hub member 32 which is provided with bolt-holes 34 positioned so that they can be brought into registration with the bolt holes of the metal wheel 10. Thus, the hub member 32 can be bolted alongside the conventional wheel with the hub member 32 sandwiched between the conventional wheel and the wheel hub of a vehicle (not shown).

Numerous variations and modifications to the illustrated safety tyre arrangements may be made without taking the resulting construction outside the scope of the present invention. To give an example, the safety tyre 16 may be joined to, or may be moulded integrally with what would otherwise be a conventional tyre 14.

Claims

1. A safety tyre arrangement, which comprises a main tyre mounted on a wheel and a safety tyre also mounted on the wheel in such a manner that the safety tyre remains unused unless and until the main tyre fails.

2. A safety tyre arrangement according to claim 1, in which the safety tyre is placed wholly within the interior of the main tyre.

3. A safety tyre arrangement according to claim 2, in which the safety tyre has an outer perimeter spaced from the inside of the road-adhering part of the main tyre.

4. A safety tyre arrangement according to any preceding claim, in which the safety tyre comprises an uninflated pneumatic tyre connected to a cylinder of compressed gas.

5. A safety tyre arrangement according to claim 4, having a trigger device arranged to be activated by failure of the main tyre.

6. A safety tyre arrangement according to claim 5, in which means are provided whereby, upon such failure, the safety tyre is inflated by gas from the gas cylinder upon activation by the trigger device.

7. A safety tyre arrangement according to claim 1, in which the safety tyre comprises a solid ring placed alongside the main tyre.

8. A safety tyre arrangement according to claim 1, in which the safety tyre comprises a solid ring placed within the main tyre,

9. A safety tyre arrangement according to claim 7, in which the ring has a smaller external diameter than the main tyre so that it only comes into contact with the ground when the main tyre fails.

10. A safety tyre arrangement according to any one of claims 7 to 9, in which the ring is made from rubber.

11. A safety tyre arrangement according to any one of claims 7 to 9, in which the ring is made of plastics material.

12. A safety tyre arrangement, substantially as described herein with reference to any Figure of the accompanying drawings.

13. A vehicle equipped with at least one tyred safety wheel mounted adjacent to a tyred main wheel of the vehicle, in which the lowermost point of the tyre of the safety wheel is higher than that of the tyre of the main wheel so that the tyre of the safety wheel does not touch the ground unless and until the tyre of the main wheel fails.

14. A vehicle substantially as described herein with reference to Figure 5 of the accompanying drawings.