The present invention relates to a rotor unit which is operable to rotate about a rotational axis, such as for the generation of mechanical or electrical power, a rotor assembly comprising one or more such rotor units, and an apparatus which incorporates one or more such rotor units or rotor assemblies.

The present invention finds application in many fields, including utilities, transportation, industrial, commercial, domestic, marine, construction, mining and space exploration. Particular applications include mechanical or electrical power for buildings, for example, supermarkets, warehouses, distribution centres, factories and datacentres, on-board power supplies for vehicles, for example, electric vehicles, ships and submarines, and portable power supplies, for example, for lighting and emergency or back-up power.

In one aspect the present invention provides a rotor unit operable to rotate about a rotational axis and generate a turning moment or torque, wherein the rotor unit comprises: a rotatable member, which is rotatable about a rotational axis; at least one reservoir, which is supported on or by the rotatable member and adapted to receive a fluid medium; and at least one fluid transfer element, which is fluidly connected to the at least one reservoir and controllable to transfer the fluid medium to and from the at least one reservoir so as to create a mass imbalance about the rotational axis and hence a turning moment or torque about the rotational axis to cause rotation of the rotatable member.

In one embodiment the rotational axis is provided by a shaft.

In one embodiment the rotatable member comprises a disc, plate or framework structure, optionally the rotatable member comprises a pair of discs, plates or framework structures between which the at least one reservoir is supported.

In one embodiment the at least one reservoir is supported on or by (i) an axial face of the rotatable member, optionally a single axial face of the rotatable member or on both opposite axial faces of the rotatable member, or (ii) a radial edge or periphery of the rotatable member.

In one embodiment the at least one reservoir includes a sensor for sensing an amount of the fluid medium within the respective reservoir.

In one embodiment at least one fluid transfer element includes a pump or compressor for transferring the fluid medium, optionally at least one fluid transfer element includes a valve for controlling transfer of the fluid medium, and optionally pressure relief.

In one embodiment the rotor unit further comprises: a controller for controlling rotation of the rotatable member about the rotational axis by controlling transfer of the fluid medium to and from the at least one reservoir, optionally a rate of transfer of the fluid medium to and from the at least one reservoir, optionally the controller includes at least one sensor for sensing a rotational position of the rotatable member, optionally at least one sensor comprises an inclinometer or gyroscope which is attached to the rotatable member.

In one embodiment the rotor unit further comprises: at least one pressure relief path which is fluidly connected to at least one reservoir to vent any accumulated pressure in the at least one reservoir with transfer of the fluid medium, optionally at least one pressure relief path includes a valve for controlling venting. In one embodiment at least one reservoir is suspended from the rotatable member.

In one embodiment at least one reservoir is (i) fluid tight or (ii) not fluid tight.

In one embodiment the rotor unit comprises: a plurality of reservoirs.

In one embodiment the reservoirs are located (i) at a single, common radius about the rotational axis, (ii) at different radii about the rotational axis, or (iii) as groups on a plurality of different radii, optionally first and second radii, about the rotational axis.

In one embodiment the reservoirs (i) have a fixed radial position, or (ii) are moveable between a first, inner radius and a second, outer radius about the rotational axis, optionally the reservoirs are movable in unison or one or more of the reservoirs are movable independently.

In one embodiment the at least one fluid transfer element is controllable to transfer the fluid medium between respective ones of the reservoirs (i) in one sense, being a clockwise sense or a counter-clockwise sense, so as to create a mass imbalance about the rotational axis and a continuous turning moment or torque about the rotational axis to cause continuous rotation of the rotatable member, or (ii) alternately in one and opposite senses by transferring the fluid medium in the one sense to cause rotation of the rotatable member in one sense and subsequently transferring the fluid medium in the opposite sense to cause rotation of the rotatable member in the opposite sense to cause oscillating or reciprocating rotation of the rotatable member, optionally the rotor unit is controlled to rotate the rotatable member through different angular rotations in the one and opposite senses. In one embodiment the rotor unit comprises: a plurality of fluid transfer elements.

In one embodiment the fluid transfer elements fluidly connect (i) adjacent ones of the reservoirs, and/or (ii) non-adjacent ones of the reservoirs.

In one embodiment ones of the reservoirs are fluidly interconnected by (i) a single fluid transfer element, and/or (ii) a plurality of fluid transfer elements.

In one embodiment the rotor unit (i) is driven by rotation of the rotatable member to move over a fixed surface, or (ii) is in fixed position and the rotatable member is driven to move a movable object.

In one embodiment the rotor unit includes one or more auxiliary drives to provide additional rotating outputs, optionally the one or more auxiliary drives are coupled by gears on the rotatable member and the auxiliary drives.

In one embodiment the fluid medium comprises (i) a liquid, optionally a suspension which contains solid particles, (ii) a gas, or (iii) a flowable solid, optionally the fluid medium comprises first and second media components of different density, optionally liquids, gases or a liquid and a gas.

In another aspect the present invention provides a rotor assembly comprising a plurality of the above-described rotor units, optionally mounted on a single or split shaft, optionally the rotor units are mounted in (i) spaced, axial relation, or (ii) stacked, juxtaposed relation.

In one embodiment the rotor units are (i) angularly shifted or out of phase by an angle (6) in relation to one another, whereby the at least one reservoir of the respective rotor units have a different axial position, or (ii) angularly in phase in relation to one another, whereby the at least one reservoir of the respective rotor units have a common axial position. In a further aspect the present invention provides an apparatus incorporating the above-described rotor unit or rotor assembly.

In one embodiment the apparatus comprises (i) a turbine, optionally a wind turbine, optionally the rotor unit or rotor assembly drives an electrical generator of the turbine, (si) a power generation apparatus, optionally the rotor unit or rotor assembly drives an electrical generator of the power generation apparatus, optionally the power generation apparatus includes a power storage unit, optionally a battery assembly, which stores generated electricity for supply on demand, (iii) a portable lighting apparatus, optionally the rotor unit or rotor assembly drives an electrical generator of the portable lighting apparatus to power lighting, or (iv) a mechanical lifting apparatus, optionally including gears and/or a pulley assembly.

Preferred embodiments of the present invention will now be described hereinbelow by way of example only with reference to the accompanying drawings, in which :

Figures 1 and 2 illustrate a rotor unit in accordance with an embodiment of the present invention;

Figure 3 illustrates a rotor unit as one modification of the rotor unit of Figures 1 and 2;

Figures 4 and 5 illustrate a rotor unit as another modification of the rotor unit of Figures 1 and 2;

Figures 6 and 7 illustrate a rotor unit a further modification of the rotor unit of Figures 1 and 2; Figure 8 illustrates a rotor unit as another further modification of the rotor unit of Figures 1 and 2;

Figure 9 illustrates a rotor unit as a still further modification of the rotor unit of Figures 1 and 2;

Figure 10 illustrates a rotor unit as a yet further modification of the rotor unit of Figures 1 and 2;

Figures 11 and 12 illustrate a rotor unit as yet another modification of the rotor unit of Figures 1 and 2;

Figure 13 illustrates a rotor unit as still another modification of the rotor unit of Figures 1 and 2;

Figure 14 illustrates a rotor unit as another modification of the rotor unit of Figures 1 and 2;

Figure 15 illustrates a rotor unit as a yet further modification of the rotor unit of Figures 1 and 2;

Figures 16(a) to (d) illustrate operation of the rotor unit of Figures 1 and 2;

Figures 17(a) to (c) illustrate one mode of operation of the rotor unit of Figures 1 and 2;

Figures 18(a) to (c) illustrate another mode of operation of the rotor unit of Figures 1 and 2;

Figure 19 illustrates a modification of the rotor unit of Figures 1 and 2 employing the mode of operation of Figures 18(a) to (c); Figures 20 and 21 illustrate a rotor assembly in accordance with one embodiment of the present invention;

Figures 22 and 23 illustrate a rotor assembly as a modification of the rotor assembly of Figures 20 and 21;

Figure 24 illustrates one apparatus incorporating the rotor unit or rotor assembly of the described embodiments;

Figure 25 illustrates another apparatus incorporating the rotor unit or rotor assembly of the described embodiments;

Figure 26 illustrates an apparatus as a modification of the apparatus of Figure

25;

Figure 27 illustrates a further apparatus incorporating the rotor unit or rotor assembly of the described embodiments; and

Figure 28 illustrates a still further apparatus incorporating the rotor unit or rotor assembly of the described embodiments.

Figures 1 and 2 illustrate a rotor unit 3 in accordance with an embodiment of the present invention.

The rotor unit 3 comprises a rotatable member 5, which is rotatable about a rotational axis X, here as provided by a shaft 6, at least one reservoir 7, in this embodiment a plurality of reservoirs 7, in this embodiment four reservoirs 7a-d, which are supported on or by the rotatable member 5 and are adapted to receive a fluid medium M, and at least one fluid transfer element 9, in this embodiment a plurality of fluid transfer elements 9, here four fluid transfer elements 9a-d, which fluidly connect respective ones of the reservoirs 7a-d and are controllable to transfer fluid medium M between respective ones of the reservoirs 7a-d, as will be described in more detail hereinbelow.

In this embodiment one, lower end of the fluid transfer elements 9a-d provides a fluid extraction point from which the fluid medium is extracted from the respective reservoir 7a-d when containing the fluid medium M, as the rotor unit 3 is rotated.

In this embodiment the fluid medium M comprises a liquid.

In one embodiment the liquid could be a suspension which contains solid particles.

In another embodiment the fluid medium M could comprise a gas.

In a further embodiment the fluid medium M could comprise a flowable solid, such as a powder or particulate substance.

In one embodiment the fluid medium M could comprise first and second media components of different density.

In this embodiment the rotatable member 5 comprises a disc, plate or framework structure 11, but could have any form which supports the reservoirs 7.

In one modification, as illustrated in Figure 3, the rotatable member 5 could comprise a pair of discs, plates or framework structures 11 between which the reservoirs 7 are supported. For ease of illustration, in relation to this and subsequent-described modifications, the fluid transfer elements 9 and ancillary components may, in whole or part, be omitted. In this embodiment the reservoirs 7 are supported on or by an axial face of the rotatable member 5.

In one modification, as illustrated in Figures 4 and 5, the reservoirs 7 could be supported on or by a radial edge or periphery of the rotatable member 5.

In this embodiment the reservoirs 7 are supported on or by a single axial face of the rotatable member 5.

In one modification, as illustrated in Figures 6 and 7, the reservoirs 7 could be supported on or by opposite axial faces of the rotatable member 5.

In this embodiment the reservoirs 7 are sealed, such that the fluid medium M passes only through any defined inlets and outlets thereto.

In this embodiment the rotor unit 3 comprises four reservoirs 7, but could comprise any number n, where n is 2 or more, such as two, three, four, five, six, seven or eight or more. Figures 8 and 9 illustrate modifications of the rotor unit 3 with six reservoirs 7a-f and eight reservoirs 7a-h, respectively.

In this embodiment the reservoirs 7 are located at a single, common radius about the rotational axis X.

In one modification, as illustrated in Figure 10, the reservoirs 7 are located as groups on a plurality of different radii, here first and second radii Rl, R2.

In this embodiment the reservoirs 7 are in fixed position at a single, common radius about the rotational axis X.

In one modification, as illustrated in Figure 11, the reservoirs 7 are moveable between a first, inner radius Rl and a second, outer radius R2. In one embodiment the reservoirs 7 are moved in unison. In another embodiment one or more of the reservoirs 7 can be moved independently.

In this embodiment the rotor unit 3 further comprises a plurality of drive elements 15 for moving each of the reservoirs 7 between the inner and outer radii Rl, R2, as required to effect rotation of the rotor unit 3.

In this embodiment the drive elements 15 each comprise a rack and pinion 17, 19, but could comprise any suitable means for moving the reservoirs 7.

In one embodiment, as illustrated in Figure 13, one or more of the reservoirs 7 can include a sensor 23 for sensing a volume of the fluid medium M within the respective reservoir 7. In this embodiment the sensor 23 senses the height or level of the fluid medium M, from which the volume of fluid medium M is determined for a given rotational position of the reservoir 7.

In other embodiments the sensor 23 could alternatively or additionally sense one or more other parameters, such as pressure, mass, strain, electrical conductivity, magnetic field, light, vibration, acoustic noise or fluid flow.

In this embodiment the sensor 23 is an ultrasonic sensor, but could comprise any kind of suitable sensor mounted in an appropriate position, such as an optical, capacitive or flow sensor, or any sensor for measuring the above- mentioned parameters.

In this embodiment the one or more fluid transfer elements 9 each include a pump or compressor 25 for transferring the fluid medium M in transferring the same.

In one embodiment at least one of the fluid transfer elements 9a-d includes a controllable valve 27 for controlling transfer of the fluid medium M and any pressure relief. In this embodiment the one or more fluid transfer elements 9 are fluidly connected to the reservoirs 7 by fluid conduits, which can be provided by any suitable means, for example, pipework, ducting or channels.

In this embodiment the fluid transfer elements 9 are fluidly connected between adjacent ones of the reservoirs 7.

In one modification, as illustrated in Figure 14, the fluid transfer elements 9 could fluidly connect non-adjacent ones of the reservoirs 7.

In other modifications the rotor unit 3 could have any arrangement of fluid interconnection between the reservoirs 7 which allows for the transfer of the fluid medium M between the reservoirs 7 in a manner which provides for a mass transfer which provides for controlled rotation of the rotatable member 5 about the rotational axis X.

In this embodiment the reservoirs 7 are fluidly interconnected by single fluid transfer elements 9, here as pairs of reservoirs 7.

In one modification, as illustrated in Figure 15, reservoirs 7 could be fluidly interconnected by a plurality of fluid transfer elements 9. With this configuration, more precise control of the transfer of the fluid medium M can be achieved between the reservoirs 7. In addition, this configuration allows for the transfer of a fluid medium M which comprises two components of different density.

In one embodiment, as illustrated in Figures 16(a) to (d), the rotor unit 3 includes at least one pressure relief path 29, in this embodiment a plurality of pressure relief paths 29, here four pressure relief paths 29a-d, which fluidly connect respective ones of the reservoirs 7a-d and vent pressure which can accumulate in the reservoirs 7a-d with transfer of the fluid medium M. Such pressure relief is not necessary in all embodiments, and can be provided by alternative means, such as an expandable member.

In one embodiment at least one of the pressure relief paths 29a-d includes a controllable valve 30 for controlling venting of accumulated pressure.

The rotor unit 3 further comprises a controller 31 for controlling rotation of the rotatable member 5 about the rotational axis X by controlling a rate of transfer of the fluid medium M between the reservoirs 7, as will be described in more detail hereinbelow.

In this embodiment the controller 31 is connected to the rotatable member 5, in order to provide power and communication, by a direct link 32, here through one or more slip rings 33, and a wireless link 34.

In one embodiment power could be provided inductively to the rotatable member 5 by inductive transfer.

In this embodiment the controller 31 includes a sensor 35 for sensing the rotational position of the rotatable member 5, which provides for monitoring of the rate of rotation of the rotatable member 5.

In this embodiment the sensor 35 comprises an inclinometer or gyroscope which is attached to the rotatable member 5. In another embodiment the sensor 35 could be an encoder, which can be mounted remotely of the rotatable member 5.

Operation of the rotor unit 3 will now be described with reference to Figures 16(a) to (d), which relate to rotation of the rotatable member 5 in one sense, being a clockwise sense as viewed. Figure 16(a) illustrates the rotor unit 3 in an equilibrium state or condition, where there is no mass imbalance about the rotational axis X and the rotatable member 5 is stationary.

As illustrated in Figure 16(b), rotation of the rotatable member 5 is initiated by the transfer of the fluid medium M between the reservoirs 7, in this embodiment from the first to fourth reservoirs 7a, d by operation of the fourth transfer element 9d, in order to create a mass imbalance, with a greater mass to one side of the rotational axis X, the right-hand side as viewed, which creates a turning moment or torque about the rotational axis X and initiates rotation of the rotatable member 5 in the one sense, with the system seeking to return to the equilibrium condition.

With continued transfer of fluid medium M between the reservoirs 7 in the same sense, in this embodiment from the first to fourth reservoirs 7a, d by continued operation of the fourth transfer element 9d, as illustrated in Figure 16(c), the mass imbalance is maintained, with a greater mass to the one side of the rotational axis X, which maintains a torque about the rotational axis X and provides for continued rotation of the rotatable member 5 in the one sense.

With further continued transfer of fluid medium M between the reservoirs 7 in the same sense, in this embodiment from the fourth to third reservoirs 7d, c by operation of the third transfer element 9c, as illustrated in Figure 16(d), the mass imbalance is maintained, with a greater mass to the one side of the rotational axis X, which maintains a turning moment or torque about the rotational axis X and provides for continued rotation of the rotatable member 5 in the one sense.

With transfer of the fluid medium M in the same sense, in this embodiment from the third to second reservoirs 7c, b and subsequently from the second to first reservoirs 7b, a, a continuous cycle can be maintained, which provides for continued rotation of the rotatable member 5 in the one sense.

Rotation of the rotatable member 5 can be stopped by ceasing the transfer of the fluid medium M.

In this embodiment the speed of rotation is controlled by a rate at which the fluid medium M is transferred between the respective reservoirs 7.

In this embodiment the turning moment or torque generated is determined by the mass of the fluid medium M which is transferred and the distance of the reservoirs 7 in relation the rotational axis X, with the greater the distance, the greater the turning moment or torque.

The rotor unit 3 can similarly be controlled to rotate the rotatable member 5 in the opposite sense, the counter-clockwise sense as viewed, which is achieved by transferring the fluid medium M in the opposite sense, that is, from the first to second reservoirs 7a, b, subsequently from the second to third reservoirs 7b, c, subsequently from the third to fourth reservoirs 7c, d and subsequently from the fourth to first reservoirs 7d, a, whereby a continuous cycle can be maintained, which provides for continued rotation of the rotatable member 5 in the opposite sense.

The rotor unit 3 can also be controlled to oscillate or reciprocate between the one and opposite senses by transferring the fluid medium M in the one sense to cause rotation of the rotatable member 5 through a required angular rotation in one sense and subsequently transferring the fluid medium M in the opposite sense to cause rotation of the rotatable member 5 through a required angular rotation in the opposite sense.

In one embodiment the rotor unit 3 can be controlled to rotate through different angles in the one and opposite senses. For ease of description, the operation of the rotor unit 3 has been described with only one of the reservoirs 7, in this embodiment the first reservoir 7a containing the fluid medium M, but a plurality or all of the reservoirs 7 could initially contain the fluid medium M. This configuration advantageously allows for greater mass transfer of the fluid medium M, which provides for a greater turning moment or torque.

The rotor unit 3 allows for various modes of operation, depending upon application.

In one mode of operation, as illustrated in Figures 17(a) to (c), the rotor unit 3 can be driven by rotation of the rotatable member 5 to move over a fixed surface S, for example, a road or rail, such as when applied to a wheel or track of vehicle.

In another mode of operation, as illustrated in Figures 18(a) to (c), the rotor unit 3 can be in fixed position and the rotatable member 5 driven to move an object O.

In one modification, as illustrated in Figure 19, the rotor unit 3 could include one or more auxiliary drives 51, in this embodiment first and second auxiliary drives 51a, b, to provide additional torque outputs as required.

In this embodiment the one or more auxiliary drives 51 are coupled by gears 53, 55 on the rotatable member 5 and the auxiliary drives 51.

In this embodiment the object O includes a rack gear 57 which engages the gear 53 on the rotatable member 5, so that the object O is moved by rotation of the rotatable member 5. Figures 20 and 21 illustrate a rotor assembly 103 in accordance with an embodiment of the present invention.

In this embodiment the rotor assembly 103 comprises a plurality of the above-described rotor units 3, in this embodiment first and second rotor units 3a, b, which are commonly mounted on a single shaft 6 in axial relation. By combining multiple of the rotor units 3, a greater torque can be achieved for a given diameter.

In this embodiment the rotor units 3 are angularly shifted or out of phase by an angle 6, here 45 degrees, in relation to one another, whereby the reservoirs 7 of the respective rotor units 3 have a different axial position. With this configuration, more precise control of the rotation of the rotatable members 5 can be achieved.

In one modification, as illustrated in Figures 22 and 23, the rotor units 3 can be stacked in juxtaposed relation, as a single integral module.

In this embodiment the rotor units 3 are angularly in phase.

The rotor unit 3 and the rotor assembly 103 as above-described have many and varied applications.

In one application, as illustrated in Figure 24, the rotor unit 3 or rotor assembly 103 could be utilized in a hub of a turbine 200, such as a wind turbine.

In one embodiment the rotor unit 3 or rotor assembly 103 could be used to drive an electrical generator of the wind turbine 200, and the blades 201 of the wind turbine 200 omitted, which would allow the tower of the wind turbine 200 to be reduced in height or omitted, and so provide a structure of relatively-low height, which would be more readily accessible. In another application, as illustrated in Figure 25, the rotor unit 3 or rotor assembly 103 could be utilized in a power generation apparatus 300 to drive an electrical generator 301, which is coupled to the shaft 6.

In one embodiment the rotor unit 3 or rotor assembly 103 is coupled to the electrical generator through a gear assembly 302.

In one modification, as illustrated in Figure 26, the power generation apparatus 300 could include a power storage unit 303, in this embodiment a battery charge controller and battery assembly, which stores generated electricity for supply on demand.

In this embodiment the shaft 6 is split and joined by couplings 6' so as to allow the components of the apparatus to be disassembled readily.

In another application, as illustrated in Figure 27, the rotor unit 3 or rotor assembly 103 could be utilized in a portable lighting apparatus 400 to drive an electrical generator 401 to power lighting 402, which is coupled to the shaft 6.

In one embodiment the rotor unit 3 or rotor assembly 103 is coupled to the electrical generator 401 through a gear assembly 403.

In still another application, as illustrated in Figure 28, the rotor unit 3 or rotor assembly 103 could be utilized in a mechanical lifting apparatus 500 to lift a load L.

In this embodiment the load L is coupled to the shaft 6 though one or more gears 501 and a pulley assembly 503. Finally, it will be understood that the present invention has been described in its preferred embodiments and can be modified in many different ways without departing from the scope of the invention as defined by the appended claims.

For example, in one modification, the rotor unit 3 or rotor assembly 103 could include a brake for stopping rotation and/or preventing rotation.

In another modification, the rotor unit 3 or rotor assembly 103 could include a vessel in which the fluid medium M can be stored, such as when not in operation or during maintenance.

In other embodiments the fluid medium M could be any composition which allows for mass transfer.