AIRBORNE VEHICULE

Abstract: An airbone vehicle includes a cabin (2) supported from a shell structure (4). The shell structure (4) is hollow and discus-shaped with a central annular through hole which is braced by struts (14, 16, 18). The shell structure (4) houses a pair of counter rotating helicopter rotor blades (6, 8). The cabin (2) is suspended from the shell structure by a shaft (30). The shaft is rigid with the underside of the shell structure at one end and pivotally connected to a carriage (32) at the other end by a universal joint. The carriage (32) is constrained for longitudinal movement along a guide (24) secured to the roof of the cabin. Displacement of the carriage along the guide displaces the centre of gravity of the cabin (2) with respect to the shell structure (4) and displacement of the universal about two axes, which extend perpendicular to one another, allows the displacement to the attitude of the shell structure (4) with respect to the cabin (2).

Description: AIRBORNE VEHICLE The present invention relates to airborne vehicles. Helicopters are generally highly manoeuvrable airborne vehicles but suffer from being relatively unstable. Traditional aircraft are much more stable in flight but are generally less manoeuvrable since they generally cannot hover over a selected spot. It is an object of the invention to provide an airborne vehicle which is both stable and highly manoeuvrable. According to the present invention there is provided an airborne vehicle comprising a body portion, a shell structure, a rotor shaft carrying rotor blades housed within the shell structure and driven by drive means, the rotor blades when rotated about the axis of the rotor shaft generating a downward thrust, the shell structure having an opening in both the roof and the underside to allow any downwardly thrust air to enter and exit and thereby effect a lift on the vehicle, and coupling means coupling the body portion to the shell structure to permit relative movement between the shell structure and the body portion to control the movement of the vehicle when lifted. An airborne vehicle embodying the present invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a side elevation of the vehicle; Figure 2 is a plan view of the vehicle; Figure 3 is a perspective view of a coupling arrangement for the vehicle; Figure 4 is a plan view of the carriage of the coupling; Figure 5 is a front elevation of the coupling illustrating its coupling to a shell structure; Figure 6 is a part cut away side view of Figure 5; Figure 7 is a front elevation of the cabin of the vehicle; and Figure 8 is a fragmentary sectional view through the leading edge of the shell structure. The vehicle shown in Figures 1 and 2 comprises a body or cabin 2 mounted on the underside of a shell structure 4 by an articulated joint assembly which will be described in more detail hereinafter. The shell structure 4 houses a pair of coaxial counter rotating rotor blades 6 and 8. The distal ends of the blades 6 and 8 carry brushes (not shown) which make sliding contact with an inner circumferential surface of the shell structure to effect a seal between each blade and the shell structure. The shell structure 4 is generally in the form of a hollow discus with coaxial upper and lower annular openings 10 and 12 in the upper and lower faces of the structure. Three parallel spaced struts 14, 16 and 18 extend across the upper circular opening 10 to give rigidity to the upper face of the structure and to support a central circular plate (not shown) . Three similar struts (not shown) extend across the lower circular opening to give rigidity to the lower face of the structure and to support a central circular plate (not shown) . Two parallel spaced cross members 20 and 22 link the three struts 14, 16 and 18 transversing the upper opening 10. Two similar cross members link the three struts traversing the lower opening 12. The central plates in the openings 10 and 12 define a generally annular through channel in the shell structure. A guide rail 24 is rigid with the roof of the cabin 2 extending parallel to, but spaced below, the strut 16. The roof also has two hatches 26 and 28 on opposite sides of the guide rail 24 to allow any operator within the cabin access to the struts traversing the lower opening 12 and the engines, to be described in more detail hereinafter. The cabin 2 may be arranged in a similar configuration to a saloon car with a drivers seat and passengers seats and space for carrying a payload. Instead of the passenger seats a clear platform for multitasking roles can be provided. Also, all the controls for the vehicle may be located in the cabin. The cabin 2 is suspended from the underside of the shell structure 4 , by a single shaft 30 which has in effect a universal joint 44 at its lower end, coupling it to the upper face of a carriage 32. The carriage 32 has front and rear pairs of toothed wheels 34 which are imprisoned in the guide 24 and engage racks 36 in the floor of the guide 24. The guide 24 is in the form of a hollow tube of rectangular section with a slot 24A in the roof along which the shaft 30 can run when the carriage is displaced along the racks 36. Either one or both pairs of wheels 36 are coupled to an electric or hydraulic motor (not shown) to effect displacement of the carriage 32. The toothed wheels 34 engaging the racks 36 ensures positive displacement of the carriage along the guide 24 without any danger of slippage. The roof of the guide is low enough to prevent the wheel being lifted off the racks. When stopped, the wheels 34 of the carriage can be locked to the racks 36 in a manner to be described in more detail hereinafter. As shown more clearly in Figure 5, the shaft 30 is rigidly secured to the underside of a platform 42 carried by the three struts traversing the lower opening 12 (only the middle strut 16A being shown) . A central support shaft 50 is rigid with, and extends between, the struts 16 and 16A. The axis of the shaft 50 passes through the centres of the two circular openings 10 and 12 and is generally coaxial with the shell structure 40. The shaft 50 rotatably supports a sleeve 52. The lower rotor blade 8 is rigid with the upper end of the sleeve 52. The upper rotor blade 8 is rotatably supported on the shaft 50 by bearings not shown. A circular plate 54 is also rotatably supported on the shaft 50 by bearings (not shown) and is located midway between the rotor blades 6 and 8. A plurality of inflatable rubber wheels 53 are equiangularly spaced around the perimeter of the plate 54. The axis of rotation of each wheel 53 is radially aligned with the plate 54 at the point at which it is supported by the plate 54. The wheels 53 are sandwiched between two coaxial discs 57 and 59. The disc 57 is rigid with the upper rotor blades 6 while the disc 59 is rigid with the lower rotor blade 8. When the lower rotor blades 8 are rotated in response to rotation of the sleeve the disc 59 will rotate the wheels 53. Rotation of the wheels 53 will rotate the disc 57 which will in turn rotate the blades 6. The wheels 53 may be four or five in number and should be sufficiently inflated to bear firmly against both discs 57 and 59. The shaft 52 is driven by two motors 56 and 58 mounted on the platform 42. The motors 56 are preferably high performance, low weight, combustion engines which are controlled from the cabin 2 by means (not shown) . The fuel storage tanks (not shown) for the engines may be distributed around the shell structure or located in the cabin. The motor 56 has a drive shaft 60 carrying a pulley 62. The pulley 62 is coupled to the sleeve 52 by a drive belt 64. The motor 58 has a drive shaft 66 carrying a pulley 68. The pulley 68 is coupled to the sleeve 52 by a drive belt 70. A differential coupling between the two motors may be provided. Four piston and cylinder assemblies 72, 74, 76 and 78 are equiangularly spaced about the shaft 30 to control the attitude of the shell structure 4 relative to the cabin 2. The piston of each piston and cylinder assembly is pivotally secured to the carriage 32 while the cylinder of each piston and cylinder assembly is pivotally secured to the platform 42. The locking system for the wheels 34 is shown more clearly in Figure 5. A rod 80 is supported for axial movement by a pair of spaced brackets 82 and 84 rigid with the carriage 32. A wedge shaped locking member 86 is located at the distal end of rod 80 for moving into and out of engagement with the nip between the wheel 34 and the rack 36. The rod 80 carries a central flange 88, located between the two brackets 82 and 84 and a coil spring 90 encircles the rod 80 to bear with one end against the bracket 84 and with the other end against the flange 88. The spring 90 thus normally urges the wedge shaped locking member 86 into the nip between the wheel 34 and the rack 36 thereby locking the wheel against movement. A cable 92 is secured at one end to the end of the rod 80 remote from the locking member 86. The cable 92 is wound around a drum 94 which is coupled to a rotary solenoid 96. When the solenoid 96 is energised the rotary drum 94 is rotated in an anti-clockwise sense as viewed in Figure 5 and thus acts to displace the rod 80 axially against the resilience of the spring 90. This now releases the locking member from engagement with the wheel 34 and the rack 36 allowing the carriage to be displaced. Each wheel is provided with a similar locking member 86 controlled in a similar manner. The control of the two locking members on the same side of the carriage can be exercised by a common rotary solenoid 96 and drum 94 as illustrated in Figure 5. The piston and cylinders 72 to 78 are controlled by a hydraulic drive (not shown) which pumps fluid from one side of the piston in each cylinder to the other thereby effecting a displacement of the piston. Also, means (not shown) are provided to vent both sides of each cylinder in an emergency to allow relative pivotal movement between the shell structure and the cabin to be effected manually by the operator opening the hatches 26 in the cabin roof and gripping the struts or any other part rigid with the struts. In a modification, handles (not shown) may be secured on the underside of the platform 42 specifically for this purpose. In operation, when the cabin is loaded with passengers, cargo and the like and ready for take-off, the motors 58 and 56 are started to drive the two rotor blades in opposite senses. With counter rotating rotor blades, the reaction is equal and opposite and so no significant reaction compensating mechanisms are required. The distal or tip portions of the rotor blades are fully shielded by the shell structure and so the turbulence they create is contained within the shell structure. Also, there is little danger of damage to or from the tip portions due to external factors. As the vehicle starts to lift, the rotary solenoid 96 is energized to release the wheels 34 of the carriage 32 and the carriage motor energised to drive the carriage 32 along the guide 24 so as to reposition the centre of gravity, of the now loaded cabin, with respect to the shell structure in accordance with the pilots requirements. The rotary solenoid is then deenergised and the wheels are locked again. As the vehicle rises above the ground its direction of movement in the horizontal plane is controlled by operating the piston and cylinder arrangements 72 to 78 to achieve the desired degree and attitude and tilt needed. The profile of the shell structure 4 enables the vehicle to achieve two special effects. Firstly, in the event of engine failure, the vehicle will tend to float to the ground rather like a stabilised parachute. The speed at the time of landing could be as low as 12% knots. Secondly, although the rotor blades when driven at top speed will enable the vehicle to achieve speeds of up to 150 knots, higher speeds can be achieved by taking advantage of the fixed wing-like shape of the shell structure and using aircraft thrust engines (not shown) , either mounted on the cabin or the shell structure, to drive the vehicle like a conventional aeroplane. When driven like a conventional aeroplane the annular openings 10 and 12 can be closed off by slidable shutters. Conventional ailerons and other controls will need to be employed to control the flight. It will also be appreciated that the profile of the shell structure will add to the lift because some of the air drawn in by the rotor blades will have been drawn across the upper surface of the shell structure. As can be seen, the described vehicle can be controlled to behave like a parachute, a helicopter or an aeroplane. The rotor blades and the drive and control mechanisms therefore can be constructed in a similar manner to that used for conventional helicopters. The heat and exhaust fumes from the engines 56 and 58 will generally be dispersed within and through the shell structure and so the vehicle will not have a significant heat signature which can be detected by third parties. In particular the gases may be fed along hollow passages in the blades from the inner radial portions of the blades towards their distal ends and discharged at the trailing edges of the blades. The noise generated by the engines and the rotor blades will also be dispersed within the shell structure. The dispersal of noise within the shell structure will make the vehicle particularly silent compared to conventional helicopters. The cabin 2 of the vehicle is shown more clearly in Figure 7. The lower portion of the cabin is in the form of a boat hull to allow the vehicle to land on water. In particular, the hull is 'W' shaped in cross-section with added stability provided by an inflatable tube 100 which extends around the perimeter of the hull. Instead, an airbag can be secured to the underside of the cabin to be rapidly inflated just prior to lading to provide for a soft landing either on the ground or on water. A pump may be used to deflate the bag and draw it close into the underside of the cabin by suction just after take-off. Entry to the cabin can be gained through the rear by a pair of tail gate doors 102 and 104. The lower door (which may rest on the tube 100 when inflated) can be used as a ramp for loading purposes. The rail 24 which is rigid with the roof of the cabin 2 extends the full length of the cabin 2 so that when the carriage 32 is moved to one or other of the extreme ends of the rail 24, the shell structure can be tilted through almost 90° with respect to the cabin 2. This is particularly advantageous when landing the vehicle on steep slopes on mountains. Of course, as the cabin touches down legs (not shown) can be extended to bite into the ground to prevent slippage down the slope. The hull may house the thrust engines mentioned hereinbefore which can then be accessed and serviced from inside the cabin. While the inflatable tube 100 is shown to be in close engagement with the exterior of the cabin, it can be mounted on telescopic struts which displace it away from the wall of the cabin to define a larger circumference and so provide for more stable floatation of the vehicle on water. The shell structure 4 has a number of additional features as shown more clearly in Figure 8. The outer circumferential portion of the shell structure is divided into a series of circumferential spaced compartments 98 each housing an inflatable member 110. Each compartment has a latchable outer flap 112 which when closed (as shown in broken lines as 112A) forms the outer surface of the shell structure. When the flap 112 is unlatched and the member 110 inflated it expands to increase the effective surface area of the shell structure. At slow speeds relatively low inflation pressure will keep the member 110 rigid. This is a feature which is particularly useful when landing the vehicle since it enables landing to take place in a more stable and controllable manner. The inflatable member 110 is preferably of rubber or other flexible material so that it acts to absorb any shock impact. This is particularly useful when the vehicle is hovering near a vertical wall since the shell structure can "bump" against the wall and resile therefrom without the disastrous consequences which would ensue from a helicopter attempting to adopt the same manoeuvre. The expansion of the member 110 is effected by feeding gas (which may be air) under pressure from a source through a conduit 114 connected to the member 112. The source of gas is a compressor (not shown) . Instead the source may be constituted by a feed pipe taken off one the engines 56 or 58. To deflate the member 110 and draw it back into the compartment 98, the member 110 is connected by a conduit 116 to a source of vacuum which may be formed by the aforementioned compressor or use of the engines 56 and 58. A concertina-like tube 118 is located within the member. The tube 118 has an axial rigidity which ensures that the member 110 collapses in a controlled manner back into the compartment 98. The conduit 116 is connected to the member 110 through the tube 118 which has a series of openings (not shown) . The flap 112 is connected to the member 110 at one point so that as the member is drawn into the compartment, the flap 112 is moved to close the compartment 98 at which point it automatically latches closed. It will be appreciated that the series of compartments 98 can be provided around the whole perimeter of the shell structure or merely around the leading edge of the shell structure in which event only a single compartment need be provided. The upper surface of the shell structure 4 is provided with grooves 120 defining arcuate sections. The arcuate sections are covered with an elastic membrane 122 with the perimeter of the membrane secured in an air tight manner in the grooves 120. A conduit 124 supplying gas from a source under pressure (not shown) has an outlet port 126 situated in the central region of the arcuate section. Thus, when gas (which may be air) is discharged from the port 126, the membrane will expand and so change the profile of the upper surface of the shell structure. The change, in profile, will effect the amount of lift which the structure enjoys as it is driven in the horizontal plane. The pilot of the vehicle can thus control the amount of lift according to his requirements. A vent valve 128 can be operated to vent the gas from the conduit 124 and so allow the membrane 122 to lie flat on the upper surface of the shell. It will be appreciated that hot gases from the engines 56 and 58 can be feed to the compartment 98 or the arcuate sections of the shell structure to de-ice the sheet structure at these locations when there is a likelihood of ice building up. It will be further appreciated that, as with other vehicles, the present vehicle can be remote controlled without the need for an on-board pilot. The rotor blades used by the vehicle as described are similar to those used in conventional helicopters. It will, however, be understood that the structure of the rotor blades can instead take a form similar to those used in gas turbines. Other geometric forms can be adopted.

Claims: CLAIMS 1. An airborne vehicle comprising a body portion, a shell structure, a rotor shaft carrying rotor blades housed within the shell structure and driven by drive means, the rotor blades when rotated about the axis of the rotor shaft generating a downward thrust, the shell structure having an opening in both the roof and the underside to allow any downwardly thrust air to enter and exit and thereby effect a lift on the vehicle, and coupling means coupling the body portion to the shell structure to permit relative movement between the shell structure and the body portion to control the movement of the vehicle when lifted. 2. A vehicle according to Claim 1, wherein the rotor blades comprise counter-rotating rotor blades. 3. A vehicle according to Claim 1 or to Claim 2, wherein the coupling means comprises a slide engaging a guide, one of said slide and guide being connected to the shell structure, and the other of said slide and guide being connected to the body portion whereby displacement of said guide relative to said slide displaces the centre of gravity of the body portion relative to the shell structure. 4. A vehicle according to any preceding claim, wherein the coupling means includes pivotal joint means which allows variation of the attitude of the shell structure relative to the body portion. 5. A vehicle according to the Claim 4 as dependent on Claim 3, wherein the joint means extends between one of said guide and slide and the shell structure or body portion to which it is connected. 6. A vehicle according to Claim 3 or to Claim 5, wherein said slide comprises a wheeled carriage. 7. A vehicle according to Claim 6, including locking means for locking said wheeled carriage in a selected position in said guide. 8. A vehicle according to Claim 4 or to Claim 5, including piston and cylinder means for controlling the attitude of the shell structure relative to the body portion. 9. A vehicle according to any preceding claim, wherein the shell structure is aerodynamically profiled to provide lift when driven in a horizontal direction. 10. A vehicle according to Claim 9, including thrust engines for driving the vehicle in the horizontal direction. 11. A vehicle according to Claim 9 or to Claim 10, including inflatable means for enlarging the circumference of the shell structure. 12. A vehicle according to any one of Claims 9 to 11, including a membrane mounted in the surface of the shell structure and means for displacing the membrane to change the profile of the surface of the shell structure and thereby its aerodynamic properties. 13. A vehicle according to any preceding claim, wherein the lower portion of the body member comprises a floatable hull to allow the vehicle to float in water. 14. A vehicle according to Claim 13, including an inflatable member encircling the hull and when inflated increasing the stability and floating properties of the vehicle. 15. A vehicle according to any preceding claim, wherein the drive means comprise combustion engines which are housed within the shell structure such that the noise and exhaust fumes therefrom are dispersed within the shell structure. 16. An airborne vehicle substantially as hereinbefore described, with reference to the accompanying drawings.

Inventors: LINNELL CLIVE JOHN, LINNELL, CLIVE, JOHN
Applicants: LINNELL CLIVE JOHN, LINNELL, CLIVE, JOHN
Application year: 1995
Main classification: B64C27
IPC codes: B64C19, B64C27, B64C39