GB2351271A - Aircraft with annular wing - Google Patents

Abstract

A six-bladed rotor 11, the blades of which may have tip-plates and winglets, causes air to flow from an inlet 9 to an outlet 20 via a passage 18 containing an annular wing 19, which generates lift as the air flows over it. Lateral control surfaces 21, and anti-torque vanes 22, may be provided, and the wing may have control surfaces (23, fig. 5). The aircraft is provided with a housing and a body 2, having a curved upper surface for creating lift. Instead of the bladed rotor, a jet engine may be used to produce the airflow.

Description

2351271 A WING AND A LIFT DEVICE USING THE WING The invention relates to a

wing and to lift devices using the wing, especially for use in aircraft.

In previous aircraft designs, two main methods of providing lift have been used, namely a fixed wing, such as the wings used for aeroplanes, and rotating blades, such as those used in helicopters.

Aeroplanes are generally provided with a fixed wing on each side of the fuselage. The movement of the aeroplane through the air results in relative motion between the air and the wings of the aeroplane which are shaped to provide lift to support the aeroplane during f light.

one major problem with f ixed wing aeroplanes of is this type is the drag caused. by the wings of the aeroplane moving through the air. In particular, vortices form at the wing tips and these vortices contribute greatly to the drag on the aeroplane.

one known way of reducing the drag is to provide winglets at the tip of each wing. These winglets are arranged to extend substantially perpendicularly to the plane of the wing and have a height which is short in comparison with the length of the wing. Winglets are effective in reducing the drag since the vortices generated at the wing tips are disrupted by the winglets and are smaller and so generate less drag when compared with a similar wing without winglets.

Also, owing to the speed the aircraft in moving while taking off and landing, a substantial amount of wear occurs on the wheels, brakes and general undercarriage area.

Helicopters are generally provided with a plurality of helicopter blades having an aerofoil cross-section which are rotated rapidly. The lift is generated by the aerofoil moving through the air by virtue of the rotation of the blades, and as a result the helicopter has an advantage that it can hover, since it is not dependent on the forward motion of the aircraft itself to provide relative motion between the blade aerofoil and the air.

However, helicopters suffer from the disadvantage that the controls are complicated and the helicopter is noisy in operation.

In particular, due to the constant change in rotor blade angle of attack, and general movement of each blade, there is much vibration with subsequent fatigue problems for structure, transmission and major lift members.

In addition, the interaction of the moving air from tail rotor and main rotor blade tips leads to is handling difficulties which must be overcome with more complicated control mechanisms.

A lif t device has also been proposed by the present applicant in a previous United Kingdom Patent No. 2270510.

The invention seeks to overcome the problems of the prior art by providing a new type of wing which reduces the drag acting on the wing compared with a normal aircraft wing and which does not require complicated control during flight.

29 In accordance with the invention there is provided a wing having a generally toroidal aerofoil.

The wing in accordance with the invention has the advantage that induced drag is eliminated owing to the lack of wing tips, resulting in an aerodynamically clean high lift ideal wing.

The invention also provides a lift device comprising a wing in accordance with the invention and means for providing a flow of air over substantially the whole area of the wing to thereby generate a lif t force in the direction generally perpendicular to the plane of the wing.

Advantageously, the lift device in accordance with the invention comprises a wing in accordance with the invention disposed within an annular passage and has means for generating a flow of air through the passage from the centre outwardly over the wing disposed therein to thereby generate a lift force in the direction substantially perpendicular to the plane of the wing.

As used herein the term "lift" refers to the force produced by an aerofoil and does not exclusively indicate a generally vertical force. In particular, for example, it should be noted that if the wing of the present invention was mounted so that the plane of the wing was generally vertical, the lift force would be is produced generally horizontally.

For a better understanding of the present invention, and to show it may be brought into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

Figure 1 shows a cross section through a lift device in accordance with the invention; Figure 2 shows an exemplary faired pylon assembly; Figure 3 shows a plan view of the lift device of Figure 1; Figure 4 illustrates the hexiform rotor in accordance with one embodiment of the invention; Figure 5 shows a plan view of the body of the lift device of Figure 1; Figure 6 shows an inverted plan view of the lift device shown in Figure 1.

An embodiment of the invention will now be described with reference to the drawings.

Figure 1 shows a cross section through a lift device 1 in accordance with one embodiment of the invention. The lift device has a body 2 which is generally circular and is provided at its circumference -4 with a lip 3. The upper surface of the body 2 is generally curved so that the body 2 is thicker in its centre than it is at its circumference.

The lift device 1 also comprises a housing 4 which is f ixed to the body 2 by means of a pillar assembly 5.

The pillar assembly 5 is preferably a faired pylon assembly having a cross-sectional shape with minimum drag. One such shape is illustrated in Figure 2.

The housing 4 has a substantially annular cross section and defines a cutout 6 in its central upper portion 7. The upper portion 7 of the housing 4 may support a top portion 8 which substantially covers the upper central part of the lift device 1 (not shown).

Alternatively the top portion 8 may be supported by the hexiform motor assembly, as described below. In any event, an annular air intake 9 is arranged between the top portion 8 and the inner edge of the housing 4.

The arrangement of the top portion 8. the annular intake 9 and the housing 4 can best be seen with reference to Figure 3. The air intake 9 may not be exactly annular, but may comprise a plurality of suitably shaped slots, for example. It is important, however, that the air intake provides a smooth flow of air into the chamber 10 of the housing 4 formed by the cutout 6.

Within the chamber 10 defined by the cutout 6 of the housing 4 and the top portion 8 there is provided a hexiform rotor 11 and an associated motor assembly 12.

The hexiform rotor 11 and the motor assembly 12 are mounted at the centre of the lift device body 2. The motor assembly 12 is mounted on a pillar assembly 13 and is coupled to the hexiform rotor 11 by a direct coupling so as to rotate the hexiform. rotor 11 relative to the body 3 and housing 4.

The top portion 8 can be attached to the top of the motor assembly 12 instead of being fixed to the housing 4.

The hexiform rotor 11 will now be described with reference to Figure 4.

The hexiform rotor 11 is provided with a toothed drive ring 14, a bearing assembly 15, an anhedrally positioned tip plate 16 and a winglet 17.

The housing 4 and the body 3 are shaped so as to form an air passage 18 in which a generally toroidal static lifting wing 19 of the present invention is provided. The static lifting wing 19 is fixed between the body 2 and the housing 4 by means of the f aired pylon assembly 5. The static lif ting wing 19 has an annular shape when seen in plan view and a standard aerofoil shape in cross section. The wing edge faces is inboard.

An upper plan view of the lift device body 2 with static lifting wing 19 in position is shown in Figure 5, and an inverted plan view of the lift device 1 is show in Figure 6.

The air passage 18 opens out into an air outlet channel 20. The shape of the air outlet channel 20 is chosen to enable a smooth flow of air without turbulence to reduce drag. In the air outlet channel of the air passage 18 there are provided lateral control surfaces 21 and anti-torque vanes 22 as shown in Figures 1, 5 and 6.

As is clearly shown in Figure 5, the static lifting wing 19 of the present invention is provided with wing control surfaces 23. The wing control surfaces 23 operate in a similar manner to the ailerons on a normal fixed wing aircraft. In the arrangement shown in Figure 5 provides control about both the lateral and the longitudinal axis of the lift device 1.

The operation of the present invention will now be described with reference to the embodiment of the invention shown in the accompanying drawings.

During operation of the lift device 1 of the present invention, the motor assembly 12 rotates the hexiform rotor 11 to draw air through the annular air intake 9 between the top portion 8 and the housing 4.

The winglets 17, which are preferably provided on the hexiform blade tips, reduce the drag caused by the rotation of the hexiform rotor 11.

Furthermore the anhedrally positioned wing tip plates 16 of the hexif orm rotor 11 guide the air drawn in by the rotation of the- he:tiform rotor 11 towards the air passage 18 and over the static lifting wing 19 of the present invention.

The air drawn in by the hexiform rotor 11 passes through the air passage 18 and over the static lifting wing 19 before passing out through the air outlet channel 20.

Since the static lifting wing 19 is positioned in the air passage 18, the flow of air through the air passage 18 generates lift.

In addition, the curved shape of the upper surface of the body 2 also creates lift.

Furthermore, the housing 4 is preferably shaped so that movement of the lift device 1 through the air also generates lift.

The anti-torque vanes 22 are provided in the air outlet channel 20 so as to prevent rotation of the body 2 owing to the operation of the motor to spin the hexiform, rotor 11.

The lateral control surfaces 21 are operable to rotate the lift device 1 about its vertical axis.

Finally, the static wing control surfaces 23 may be used to control the movement of the lift device 1 about the lateral and longitudinal axes.

Although the present invention has been described with reference to the hexiform rotor 11, it will be clear that any arrangement to produce the flow of air through the air passage and over the static lifting wing may be used. In particular, it is envisaged that other airflow generators, for example a jet engine, may be used instead of the hexiform rotor.

Further control means may be added to the lift device of the present invention. In particular, movable weights may be provided to alter the centre of gravity of the lift device, to provide additional control of the movement of the lift device in the lateral and longitudinal directions.

In addition, it is clear that the invention is equally applicable to both small and large lift devices.

In particular, it is envisaged that the lift device of the invention can be used as a toy or to carry small objects, such as a camera, for example, but could also be dimensioned to carry one or more people or larger objects.

Clearly, the means for controlling the various control surfaces of the lift devices of the invention should be adapted to the likely forces acting on the lift device control surfaces.

In accordance with the invention there is therefore provided a new type of highly effective wing 2 and an associated lift device.

Claims (15)

CLAIMS:

1. A wing having a generally toroidal aerofoil.

2. A lift device comprising a wing as claimed in claim 1 and means for providing a flow of air over substantially the whole area of the wing to thereby generate a lift force in the direction generally perpendicular to the plane of the wing.

3. A lift device as claimed in claim 2 comprising means for generating a flow of air and means for guiding the flow of air over the wing.

4. A lift device as claimed in claim 3, wherein the lift device has an annular passage within which the wing is disposed and the air flow generating mean generates a flow of air through the passage from the is centre outwardly over the wing disposed therein.

5. A lif t device as claimed in one of claims 3 or 4. wherein the means for generating a flow of air is a jet engine.

6. A lift device as claimed in one of claims 2 5, wherein the wing has control surfaces to control lift generated.

7. A lift device as claimed in one of claims 2 6, wherein the body of the lift device is shaped to produce lift.

8. A lift device as claimed in one of claims 2 7, wherein the exit airflow path is aerodynamically clean.

9. A lift device as claimed in one of claims 2 8. wherein lateral control surfaces are provided in the outlet of the air passage.

10. A lift device as claimed in one of claims 2 9, wherein the means for generating a flow of air is a hexiform. rotor.

11. A lif t device as claimed in claim 10, wherein the air intake to the hexiform rotor is uniform.

12. A lift device as claimed in claim 10 or 11, wherein anti-torclue vanes are provided in the outlet of the air passage

13. A lift device as claimed in one of claims 10 12 wherein the hexiform rotor has a tip plate to guide airflow to the wing.

14. A lift device as claimed in one of claims 10 13 wherein the hexiform rotor has a winglet to reduce drag.

15. A lift device substantially as herein described with reference to the accompanying drawings.