It is one object of this invention to provide a power generator able to utilise natural energy in an efficient manner.

According to the invention there Is provided a rotary drive structure having a central shaft linked by drive members to individual shafts of vane-like blades whose rotational axes are located in symmetry around a circle centred on said central shaft, the drive members being arranged such that each blade will rotate in one direction as the array of blades rotates around said circle in the opposite direction, each of the blades having a cross-sectional line of elongation which at all times, during rotation, will point to or through a single fixed reference point lying on said circle.

If such a structure is used, for example, to harness wind power, the wind will attack the blades in such a way that there will always be an overall imbalance of effort applied to the collection of blades which will cause the whole assembly to rotate about the central shaft. As this occurs, the blades themselves rotate at half the speed of the central shaft rotation. The result of this is that there is always a sufficient surface area of the whole collection of blades facing the wind to cause the assembly to rotate about its central shaft, so that a continuous rotational output of the central shaft can be used as a power

source. Because each blade is caused to be aligned such that it points towards the fixed reference point at all times, this ensures that the whole assembly of blades are aligned at any one time in such a way that there is a substantial surface area of the assembly of blades facing the wind with very little potential for the wind to press on the other surfaces of the blades in a manner which would deter the rotation of the assembly in the desired manner. Of course, the wind can change direction, but the effect of this will be to cause the assembly to turn, as a result of the new pressure pattern applied to the blades, until a point is reached where the maximum effect of the wind onto the blades is achieved. If the wind changes direction totally, then the assembly will be caused to rotate about the central shaft in the opposite direction, but there will still be a power , output from the rotating shaft.

Preferably the drive members will be so arranged that the blades will rotate through 180° as the central shaft rotates through 360° The drive members themselves can be cog wheel or crown and pinion linkages between the central shaft and the individual shafts. Thus, the drive members could include cog wheels on the shafts and intermediate idler cog wheels between the cog wheel on the central shaft and those on the individual shafts. In some instances it may be preferable that at least some of these cog wheels on the individual shafts are interconnected with one another rather than to the cog wheel on the central shaft. As an alternative the drive members could be belt drives between pulley wheels mounted on the individual shafts and/or mounted on the central shaft and on the individual shafts.

Any number of blades (in excess of one) may be employed, although for

most instances an array of four blades is likely to be the optimum arrangement.

The blades could be of differing sizes so long as they are symmetrically arrayed around the central shaft. The requirement for a symmetrical arrangement of the blades is intended to indicate an arrangement whereby a similar force affect will be applied to the array of blades at all stages of rotation of the assembly when subjected to a constant uni-directional force (wind, tide etc).

The blades themselves can be formed in desirable cross-sectional shapes, although the preferred shape may be in the form of a narrow ellipse with pointed ends.

The central shaft can be linked to one or more power supply members.

The structure may employ a series of power supply members, each of which may be engaged with the central shaft, thus enabling a variable number of power supply members to be driven by the central shaft at any one time.

As an alternative, a motor could be connected to the central shaft to enable the blades to be driven in the manner of a propeller. In other words, the operation of the structure is essentially reversed from that providing a power supply harnessing wind energy or the like. The propeller can form part of a boat or aircraft propulsive drive mechanism.

The invention also extends to a drive assembly comprising a sequence of rotary drive structures of this invention of the form as defined hereinabove, the structures being set in a continuous line. Such a structure might well be used to extend across the width of a tidal stream or over an area to take advantage of wave power. With such an arrangement it may be helpful to provide deflector panels between adjacent pairs of rotary drive structures

The invention may be performed in various ways and a number of preferred embodiments thereof will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 illustrates in side and plan view features of a preferred form of power generator of the invention for harnessing wind power; Figures 2 to 5 illustrate various stages of rotation of the structure of Figure 1; Figures 6 and 7 illustrate power forces applied to blades of the assembly of Figure 1; Figure 8 illustrates a modified blade assembly with blades of differing sizes ; Figure 9 illustrates various types of blade assembly with differing numbers of blades ; Figures 10 to 13 illustrate alternative means of interconnecting the blades of the device of Figure 1 to a central shaft; Figure 14 illustrates a means for applying the output of the device to a series of power supply members; Figures 15 to 17 show alternative drive assemblies for a structure similar to that of Figure 1; Figure 18 illustrates stages of construction of a form of wind-driven power generator of this invention; Figures 19 and 20 show wind driven power generators of differing sizes; Figures 21 and 22 illustrate methods of mounting a water-flow-driven power generator and a wind-driven power generator respectively of this

invention; Figures 23 and 24 are side, plan and perspective views of a wind-driven power generator of this invention utilising a pair of rotary drive structures; Figure 25 comprises side and plan views of a power generator driven by water flow and incorporating a pair of rotary drive structures; Figures 26 to 30 illustrate various features of a multiple array of rotary drive structures to be driven by water flow ; Figures 31 and 32 show alternate forms of rotary drive structures intended for mounting with the central shaft set horizontally ; Figures 33 to 35 show aspects of the design of a power generator utilising wave energy; Figures 36 and 37 illustrate two types of multiple assembly using power drive structures set in pairs; Figure 38 is a multiple assembly incorporating rotary drive structures intended to be driven by a combination of water flow, wave power and wind power; Figure 39 illustrates a ship design whose power source is a rotary drive structure of this invention; Figures 40 and 41 illustrate features of a propulsion drive for a boat utilising a rotary drive structure of the invention; Figures 42 and 43 show a propulsion drive for a ship utilising a pair of rotary drive structures of the invention; Figures 44 and 45 show a number of possibilities for the shapes of blades to be used in the rotary drive structures;

Figures 46 to 48 illustrate various cross-sectional shapes to be employed for blades of rotary drive structures of the invention.

Figures 49 and 50 disclose modified forms of blade and drive arrays for devices of the invention; Figures 51 and 52 illustrate, in vertical section and perspective views, a proposal for a fan device of the invention; Figures 53A to 53D comprise plan, side, front and perspective views respectively of a flying machine incorporating a drive mechanism of the invention; Figures 54A and 54B comprise plan and front views respectively of an aeroplane incorporating the drive mechanism of the invention; and Figure 56 illustrates features of an outboard motor design incorporating the drive mechanism of this invention.

A typical design of power generators of this invention is illustrated in Figure 1. As can be seen from the side and plan views, the assembly incorporates a series of four blades 1 of vane-like form whose cross-sectional shape is a narrow ellipse with pointed ends. Each blade 1 is mounted on a shaft 2 in a support structure incorporating an integral cog wheel 3. Each of the four cog wheels 3 are linked by idler cog wheels 4 to a central cog wheel 5 located on a central shaft 6. The shaft 6 is in turn attached to a cog wheel 7 which drives power supply members 8 via further cog wheels 9. Alternatively, the extension 10 of the central drive shaft 6 could itself provide the power output of the device. The various parts of the assembly are mounted on supporting plates or ribs 11 and 12.

If the assembly is in the form of a wind powered generator with the wind approaching, say, from the bottom right of the assembly as shown in Figure 2, the balance of a wind force applied to the various blades 1 will be such as to cause the assembly of blades to move round in a clockwise direction so that, for example, after a period of time, blade 1A in Figure 2 will have moved to the alternative position shown in Figure 3. An intermediate position, between the two positions illustrated Figures 2 and 3, is shown in Figure 4. Because of the interlinking of the various cog wheels 3,4 and 5, the blades 1 will be caused to rotate about the shafts 2 in an anti-clockwise manner and similarly the central shaft 6 will also rotate in an anti-clockwise manner, although the array of shafts 2 and blades 3 rotates in a clockwise direction. At the same time, the cross- sectional line of elongation of each blade 1 will always point through an imaginary fixed single reference point X lying on a circle through the four shafts 2. This can be seen clearly from Figures 2,3 and 4. Figure 5 illustrates various positions of rotation of a blade 1 indicating how the blade is always aligned with the imaginary fixed point X, the device being subjected to a wind force indicated by the arrows 13. Figure 6 shows the resultant forces applied to the blades 1 from a wind force in the direction from the bottom of the drawing. The lines 14 indicate the limits of the drive force and the line 15 indicates the total force applied to each shaft 2. In this condition, the wind power initially will only be affecting blades 1A and 1B as blade 1C will be in"shadow"and blade 1 D will be aligned with the wind. A similar force relationship is indicated in Figure 7 for a modified construction where six evenly spaced blades 1 are provided.

Figure 8 illustrates a modified arrangement wherein alternate large blades

1X and small blades 1Y are symmetrically arrayed around the circle defined by the shafts 2. The blades 1X and 1Y are positioned in such a way that their rotational envelopes. do not overlap.

As shown in Figure 9, any convenient number of symmetrically arrayed blades 1 may be employed, ranging from two blades in Figure 9A up to 12 in Figure 9H. Where large numbers of blades are employed (such as in Figures 9G and 9H) it will be necessary to interlink the cog wheels 3 with one another in a circular array, connected by just one idler cog wheel 4 to the central cog wheel 5 located on the central shaft 6.

An alternative form of gear structure is shown in Figure 10 wherein the cog wheels 3 carry twice as many teeth as the idler cog wheels 4 and the central cog wheel 5. This has the effect of ensuring that the blades 1 rotate through half a revolution as compared with the rotation of the central shaft 6.

An alternative drive assembly to the use of cog wheels is illustrated in Figure 11. Here, rack and pinion arrangements 16 are employed to link the outer cog wheels 3 to the central cog wheels 5. Such an arrangement is also shown in Figure 9C.

Another alternative construction is to utilise a belt drive 17 running around pulley wheels 18 which replace the cog wheels 3. One of the pulley wheels 18 will then be driving connected to a pulley wheel 19 on the central shaft 6 (possibly via an intermediate pulley wheel 20) as illustrated in Figure 9E. An alternative, as shown in Figure 9F, is to incorporate one outer cog wheel 3, linked to one of the pulley wheels 18, such that the driving connection to the central shaft 6 is via an idler cog wheel 4 and the central cog wheel 5. Figure 13

shows a more complicated interconnecting drive arrangement utilising a toothed belt, a chain, or a pulley belt 21 interlinking the four blades 1 through their pulleys 18, with further drive connections provided from the central shaft 6 to an output drive shaft 22. An assembly of this nature is more suited to a power generator structure where the shafts 2 etc are set horizontally and with a sequence of sets of blades 1 set in line.

As shown in Figure 14, the central shaft 6 of an array could be connected to a ring 23 carrying external teeth which can mesh with cog wheels 24 mounted on a series of generators 25. Suitable clutch arrangements will be provided to enable any desired number of generators 25 to be lined up to the ring 23 so that the rotational speed of the turbine can be reduced during high winds by increasing the number of aenerators 25 which are connected to the ring 23.

Figures 15,16 and 17 illustrate alternative locations for the gear wheels 3,4 and 5 and the drive gear wheels 7 and 9. Thus, both sets could be located below the blades 1 as shown in Figure 15; above and below the blades 1 as shown in Figure 16; and all above the blades 1 as shown in Figure 17. In the form of Figure 16, the power generators 26 will be located at the top of the assembly.

Figure 18 shows steps in the assembly of a wind power generator.

Firstly, the blades 1 will be located between the support plates 11 and 12, with the various gears 3,4, 5,7 and 9 set in position. Then, as shown in Figure 18B, capping members 27 and 28 will be fitted on to cover the working parts. In the alternative assembly shown in Figure 18C, the blades 1 will be set totally within the envelope created by the outer perimeters of the capping members 27 and

28. A protective cage 29 can be applied around the blades as shown in Figure 18D. Such a blade structure is shown in Figure 19 where the wind power generator is mounted on a garden wall 30 to act as a small power source. A much larger structure is shown in Figure 20 in the form of a substantial electricity power generator set above a building 31.

As shown in Figure 21 the rotary drive structure could be located in a river so that the flow of water will drive the blades 1. A deflector 32 is provided at the front of the structure. The assembly can be mounted on a post 33 fixed to the river bed and further supported by struts 34 connected to the river bank. A wind powered generator shown in Figure 22 is set above the ground on a post 35 and is fixed by support cables 36 leading down to the ground.

As shown in Figures 23 and 24, a pair of rotary drive structures could be located into a single assembly. Such an arrangement will be used when the driving force will be in a substantially constant direction (such as tidal or river flow movement). The outer casing 37 will carry a vane 38 which will keep the device in the desired orientation relative to the flow. The vane 38 will also extend inwardly between the two drive structures as shown in Figure 23.

A further dual assembly is shown in Figure 25 wherein two rotary drive structures are set within an enclosure 39 having inlets and outlets at 40 and 41.

A whole array of rotary drive structures could be set in line to utilise fluid movement such as tidal movement. Such an assembly is shown in Figure 26. A series of rotary drive structures could also be set in line in channels constructed to interconnect the bends of a meandering river as shown at 42 in Figure 27.

A multiple array of rotary drive structures is shown in Figure 28. As can

be seen, these are set in pairs between deflector structures 43. Figure 29 illustrates a dual rotary drive structure where the inlet flow region 44 is restricted by deflector plates 45. In a multiple assembly, again the deflector plates 46 can be provided between pairs of rotary drive structures as shown in Figure 30. The deflector plates 46 will be pivotally arranged. Thus when the fluid flow is in the one direction as shown in Figure 30A, the deflector plates 46 will be aligned with that flow direction. When the flow changes direction, as shown in Figure 30B, then the deflector plates will all rotate to the alternative positions as illustrated.

Figure 31 shows a rotary drive structure wherein the central shaft 6 and the shafts 2 for the blades 1 are set horizontally. The main output drive can then be via a shaft 47 to a power output device 48, or as shown in Figure 32, via a pair of gear wheels 49.

A wave power generator is illustrated in Figure 33 to 35. Here, the shafts 2 and 6 are set horizontally and the waves will break on the blades 1 from one direction and cause the drive structure to rotate and thus provide a power output. As shown in Figure 34 the outer support structure 50 for the device can be held by cables 51 leading to anchors. Floats 50A will help to keep the structure 50 in a desired location relative to the surface of the water (which will of course vary as the tide rises and falls). Alternatively, the outer support . structure 50 could be mounted slidably on an assembly 52 secured into the sea bed 53. Again floats 50A will help to keep the structure 50 at the desired height.

Figures 36 and 37 illustrate particular designs of deflector vanes 54 and 55 which can be employed with multiple arrays of rotary drive structures. It will be noted in Figure 37 that there is a degree of overlap between the envelopes of

the rotary drive structures of each pair. However, this overlap is designed in such a way that the blades 1 will never clash.

As shown in Figure 38, a multiple structure may be provided on a support column 56. This carries a tidal flow power generator 57 below sea level, a wave power generator 58 at sea level, and a wind power generator 59 above the sea surface. Floats 58A are provided to help keep the structure 58 at a desired level by sliding up and down support struts of the support column 56. By this means all three forms of available power source (tide, wave and wind) can be utilised in one power supply structure.

Figure 39 shows how the rotary drive structure could be provided in the form of a mast-like arrangement 60 for a ship 61. Power from an output shaft 62 can then be utilised to drive a propellor 63.

The purpose of the rotary drive structure can be reversed so that a power input can provide a rotary output such as for the propellor 64 of an outboard motor 65 (Figure 40). In the arrangement of Figure 41 an engine will drive an input shaft 66 so that, through suitable gearing, the blades 1 of the rotary drive structure will be rotated in the manner of a propeller. A more substantial propeller design 67 is shown in Figure 42, located in a conventional manner ahead of a rudder of a ship 69. For larger ships, a pair of propellers 70 could be provided either side of the rudder 71 as shown in Figure 43.

In most cases, the blade 1 will be of constant dimensions throughout its length as shown in Figure 44A. The shape could be modified by elongation in either direction as shown in Figures 44B and 44C. Furthermore, the shape of the blade 1 from top to bottom could be modified as desired, as illustrated in the

other drawings in Figure 44. Figures 45A and 45B show how the blade could be in the form of a canvas panel 72.

Figure 46 indicates various ways in which the cross-sectional shape of the blade 1 can be modified to suit particular purposes. Figures 47 and 48 illustrate further modifications to the cross-sectional shape of the blade 1.

In Figure 49 it will be noted that six blades 1 are provided, linked by a drive belt 74 to a gear drive mechanism which incorporates a large cog shaft 6.

Figure 50 has the blades 1 linked by crown and pinion drives 76. to large cogwheels 77 adjacent to the driven shaft 6. In both these arrangements the location of large cogwheels near to the centre of the structure reduces the weight on the outer edge of the support arrangement.

Figures 51 and 52 illustrate how the blades 1 could be driven within an enclosed housing 78 to provide a flow of air 79, in the nature of a fan. This structure could also be used as a spraying device or as a pump.

Figure 53 illustrates how a rotary drive structure 80 could be mounted either side of a carrier device 81 so that the whole construction could be operated in a manner similar to that of a helicopter.

Figure 54 illustrates the incorporation of rotary drive structures 82 of this invention in association with each wing 83 of an aeroplane. Figures 55A, 55B and 55C illustrate how the fixed reference point (to which the blades 1 are aligned during rotation) can be shifted so as to alter the thrust direction of the force applied by the rotary drive structure to the aeroplane. With the device set in the direction shown in Figure 55A the thrust will provide lift to raise the aeroplane vertically. The modified positioning of the device in Figure 55B will

provide a force to cause the aeroplane to climb in an angled direction. With the device set in the position shown in Figure 55C, the rotary drive structures will provide for forward movement of the aeroplane.

Figure 56 is a representation of an outboard motor proposal utilising a pair of rotary drive structures of the invention similar to that shown in Figure 41.

In this instance, however, cogwheel arrays 84 are provided on both sides of each set of blades 1 and the sets of cogwheels are rotated, together, by a chain or vee-belt 85.