GB2247659A

GB2247659A - Aircraft wheel with means to rotate it

Info

Publication number: GB2247659A
Application number: GB9119666A
Authority: GB
Inventors: Gerard Ian Hamilton
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-09-10
Filing date: 1991-09-06
Publication date: 1992-03-11
Also published as: GB9019755D0; GB9119666D0

Abstract

A tyre (7) for an aircraft landing wheel or the wheel itself, has a plurality of resilient cup members (1) attached to the wall. Each cup member (1) is formed from a flat disc of rubber or plastics of about 2 mm thickness with a section cut out so that it can be bent and joined along the edges (3, 4) to form a cup with an opening (2). The circumference of the cup is secured to the tyre or wheel by adhesive. Air from the slipstream enters the openings (2) of the lowermost cup members to inflate them and cause the wheel to rotate while the cup members passing round the upper part of the wheel tend to deflate to reduce drag. <IMAGE>

Description

TITLE Improvements in or relating to Aircraft Undercarriage Svstems This invention relates to improvements in or relating to aircraft undercarriage systems and is particularly concerned with an undercarriage system for an aircraft with retractable wheels, wherein the wheels and tyres are set into rotation prior to touch down, to increase tyre life and aircraft safety.

Broadly, and in accordance with this invention, there is provided an aircraft undercarriage system wherein one or more of the wheels thereof incorporates means to impart rotation thereto using energy extracted from the slipstream.

In one preferred embodiment for carrying the invention into effect the said means comprises a plurality of cup shaped members attached to the rotating structure of a wheel or tyre with the cup members serving to impart rotation. Advantageously each cup member is constructed from a flexible plastics or rubber material and is arranged to inflate to extract energy from the slipstream on one side of the wheel. and to deflate to reduce drag at the other side of the wheel.

This invention is further described and illustrated with reference to the accompanying drawings which show one embodiment by way of example only.

In the drawings: Figure 1 shows a cup member in flat form, Figure 2 shows the cup member prior to application to a wheel tyre, Figure 3 shows a side view of an aircraft landing wheel, and Figure 4 shows a front view of an aircraft landing wheel.

Referring to the drawings, a flat circular sheet of rubber material having a thickness of some two millimetres, as example, has a section 2 cut out so as to leave a portion 1 which may be formed into a cup shape. The sides 3 and 4 thus formed are brought together in abutment as shown in Figure 2, this deforming the sheet into a generally cup shaped member. The outside radius of 3 and 4 to the inside radius of 3 and 4 approximately governs the attachment area around the whole of the device, which is secured to the outside edge of the tyre by means of adhesive. This leaves the inner edge 5 forced outwards to act as a cutting edge to inflate the cup. As shown in Figure 3, an aircraft landing wheel 6 has a rubber tyre 7 with the assembly being attached to an undercarriage leg 8.Around the side peripheral portion of the tyre 7 a plurality of cup members 1 are secured in the manner previously referred to. The embodiment shown in Figure 3 has twelve such cup members secured around the periphery although this number may be varied and is considered as not limiting.

As shown in Figure 4, assuming the incident air flow due to the slip stream is directed into the drawing then the cup members 1 which are located on the wheel adjacent to the lowermost portion thereof will be inflated and extract energy from the air flow to cause rotation of the wheel. Due to the flexible nature of the material used for the cup 1, as same rotates with the wheel, the air flow incidence will change to the side and finally to the rear when the cup reaches the uppermost point. The cup will be deflated during this motion thus providing reduced drag on the forwardly moving upper part of the wheel.

A feature of the arrangement is that the construction is not rigid and can break or tear free of the wheel without causing damage.

The dimensioning of the cup members, the number and their position on the wheel can be varied to provide the necessary rotational speed which, to a greater extent, will depend upon brake drag and friction together with the extent of slipstream in the vicinity of the undercarriage structure.

The arrangement can be adapted to existing aircraft undercarriages without substantial modification and without affecting existing structural integrity.

The wheel may include means to control the rate of rotation between required limits.

Claims

1. An aircraft undercarriage system wherein one or more of the wheels thereof incorporates means to impart rotation thereto using energy extracted from the slipstream.

2. A system in accordance with Claim 1, wherein the said means comprises a plurality of cup shaped members attached to the rotating structure of a wheel or tyre with the cup members serving to impart rotation.

3. A system in accordance with Claim 2, wherein each cup member is constructed from a flexible plastics or rubber material and is arranged to inflate to extract energy from the slipstream on one side of the wheel and to deflate to reduce drag at the other side of the wheel.

4. An aircraft undercarriage system or a tyre constructed and arranged to function as described herein.

5. An aircraft including a system as described herein or as claimed.