WO2021005522A1

WO2021005522A1 - Rotary vane device

Info

Publication number: WO2021005522A1
Application number: PCT/IB2020/056414
Authority: WO
Inventors: Philip Reuben NICHOLSON; Stephen Reuben NICHOLSON
Original assignee: Azamour Investment Corporation Incorporated; BEHARIE, Tertia
Priority date: 2019-07-08
Filing date: 2020-07-08
Publication date: 2021-01-14

Abstract

This invention relates to a rotary vane device and more particularly but not exclusively, to a rotary vane engine, pump or compressor. The invention also relates to a rotor assembly suitable for use in such a rotary vane device. The rotor includes a cylindrical rotor body including a plurality of longitudinally extending receiving slots, the cylindrical rotor body having a longitudinal axis; and a plurality of vanes, wherein a vane is slidingly locatable inside a receiving slot. The vanes are biased away from the cylindrical rotor by way of a magnet arrangement including elongate vane magnets located in the vanes, and opposing rotor magnets located at least partially inside a core of the rotor body. The rotor is characterized in that the vane magnets are orientated to form an acute angle relative to a longitudinal axis of the rotor body.

Description

ROTARY VANE DEVICE

BACKGROUND TO THE INVENTION

THIS invention relates to a rotary vane device and more particularly but not exclusively, to a rotary vane engine, pump or compressor. The invention also relates to a rotor assembly suitable for use in such a rotary vane device.

Rotary vane devices such as engines, pumps and compressors are well known in the art. One common embodiment of this technology utilizes a rotor having a plurality of vanes extending radially outwardly from radial slots provided in the rotor body, with the vanes being radially displaceable relative to the rotor. More particularly, the vanes of a rotary vane device travel in and out of the rotor, and in particular in and out of the slots, as they move along the interior walls of the housing of the rotor. Centrifugal force or springs are commonly used to urge the vanes towards or against the outer wall. In their extended state, these vanes adjust to the housing’s (or cylinder’s) profile while being driven by the rotor. The displaceable vanes, used in combination with a rotor mounted offset relative to a cylindrical housing in which it is located, result in the formation of varying volume chambers between the rotor and the housing, with the volume of a chamber changing as the rotor rotates relative to the housing. Common uses for a rotary vane pump include hydraulic fluid compression and compressed air pumps, for example in aircraft or trucks. Small rotary vane pumps can also be used for drink dispensers, medical dispensing pumps, water pumps on marine engines, compressed air drills and many other applications. The materials used to make the pump and vanes can be modified for high -temperature industrial applications such as furnace air injection or engine turbocharging. Rotary vane pumps also work well as vacuum pumps for example in aircraft applications, laboratory vacuum systems, medical applications and also to evacuate and recover refrigerants from air conditioning systems. Rotary vane engines are also known in the art. In short, the applications of rotary vane devices are almost endless, and growing rapidly.

A good seal is required between the end of a displaceable vane and the housing surface in which the rotor is located in order to maintain the efficiency of the rotary vane device. Centrifugal forces exerted on the vanes inherently contribute to ensure that a good and dynamic seal is formed between the end of a vane and an inner surface of a rotor housing. However, in some cases centrifugal forces are not sufficient, and it has accordingly been proposed to use springs to augment the outwardly directed bias of the rotating vanes. The downside of this approach is that springs wear over time, which adversely affects the performance and reliability of a rotary vane device incorporating spring driven vanes. In addition, it also complicates the maintenance of the device.

It has also been proposed to use magnets instead of springs to provide the required bias. Although this works well, some shortcomings are associated with this solution in certain applications. For example, there is limited space to mount magnets in both the vanes of the rotor and the rotor body, and the maximum magnetic flux that can be obtained is therefore limited by the size and number of magnets that can be used due to geometrical constraints. One way of overcoming this disadvantage is presented in the applicant’s co pending application ZA2014/03295 entitled “Rotary Vane Device”, the contents of which is incorporated herein by reference. In this embodiment, rotor magnets are located in the body of the rotor adjacent the vanes, and not operatively below the vane slots as is known in prior art applications. It has also been proposed for the rotor magnets to be located in the hollow core of the rotor, thus allowing the use of more magnets, and hence increased flux. This concept is disclosed in the applicant’s patent application WO2016/157090 entitled “Rotary Vane Device”, the contents of which is incorporated herein by reference.

The above designs result in increased magnetic flux insofar as the magnets located in the rotor (referred to as“rotor magnets”) are concerned, but the geometry of the vanes is still a limiting factor in terms of accommodating magnets in the vanes (referred to as“vane magnets”), and hence increasing the vane magnet flux. The vane magnets are generally in the form of elongate, cylindrical magnets. If the vane magnets are orientated perpendicularly relative to a longitudinal axis of the rotor, the exposed area of a magnet is limited (i.e. only one end is exposed to the rotor magnets) and the flux is therefore limited. If the magnet is turned sideways (i.e. parallel to the longitudinal axis of the rotor along an inner end of the vane), a larger area of the magnet can be exposed to the rotor magnets, but in that configuration a large weakened zone is formed in the inner end of the vane, which in turn results in an increased chance of breakage of the vane (due to shearing) when a moment is induced about the vane.

It is accordingly an object of the invention to provide a rotary device that will, at least partially, alleviate the above disadvantages.

It is also an object of the invention to provide a rotary device which will be a useful alternative to existing rotary devices. It is a still further object of the invention to provide a rotor for used in a rotary device that will, at least partially, alleviate the above disadvantages.

It is another object of the invention to provide a rotor for a rotary device which will be a useful alternative to existing rotors.

SUMMARY OF THE INVENTION

According to the invention there is provided a rotor, suitable for use in a rotary device, the rotor including:

a cylindrical rotor body including a plurality of longitudinally extending receiving slots, the cylindrical rotor body having a longitudinal axis; a plurality of vanes, wherein each vane is slidingly locatable inside a receiving slot; and wherein the vanes are biased away from the cylindrical rotor by way of opposing magnets located in the vanes and the rotor;

the opposing magnets including a vane magnet arrangement located in each end zone of a vane, and an opposing rotor magnet arrangement located at least partially inside a core of the rotor body; characterized in that a plane dividing a vane magnet arrangement between north and south poles is orientated to form an acute offset angle relative to a longitudinal axis of the rotor body.

There is provided for the rotor to include one or more elongate magnets having a longitudinal axis that is orientated to form an acute offset angle relative to a longitudinal axis of the rotor body.

There is provided for the or each elongate magnet to have a longitudinal plane extending through a longitudinal axis of the magnet and which divides the magnet into two elongate polar halves, wherein two poles of the magnet are located on opposite sides of the longitudinal plane of the magnet. A further feature of the invention provides for the offset angle to be between 10 degrees and 60 degrees relative to the longitudinal axis of the rotor body, preferably between 20 degrees and 40 degrees, more preferably about 30 degrees.

The rotor magnet arrangements may be located in end zones of the rotor body. Preferably, the rotor magnet arrangements are located inside receiving pockets formed in the ends of the rotor body.

The rotor magnet arrangements may be of at least partially conical or frusto- conical configuration.

There is provided for each rotor magnet arrangement to include a cylindrical base section, and a conical section extending from and around a perimeter of the base section, wherein one of the poles of the magnet corresponds with the base section, and wherein another of the poles of the magnet corresponds with the conical section.

An angle between the longitudinal axis of the vane magnet arrangement and the conical section of the rotor magnet arrangement may be less than 10 degrees, preferably less than 5 degrees, more preferably less than 2 degrees.

There is further provided for each vane to include shoulder sections of reduced height at distal ends of the vane, with the vane magnet arrangements located in the shoulder sections.

Operatively inners ends of the shoulder sections may be of tapering configuration in order to reduce an angle between the longitudinal axis of the vane magnet arrangement and an inner end of the vane.

There is also provided for distal ends of the receiving slots to be complementary tapered to the shoulder sections of the vanes in order to reduce the distance between a vane magnet arrangement and a rotor magnet arrangement.

According to a further aspect of the invention there is provided a rotor, suitable for use in a rotary device, the rotor including:

a cylindrical rotor body including a plurality of longitudinally extending receiving slots, the cylindrical rotor body having a longitudinal axis; a plurality of vanes, wherein a vane is slidingly locatable inside a receiving slot; and wherein the vanes are biased away from the cylindrical rotor by way of opposing magnets located in the vanes and the rotor;

the opposing magnets including a vane magnet arrangement located in each end zone of a vane, and an opposing rotor magnet arrangement located at least partially inside a core of the rotor body; characterized in that the vane magnet arrangements located in the vanes are orientated to form an acute angle relative to a longitudinal axis of the rotor body.

According to a further aspect of the invention there is provided a vane, suitable for use in a rotary device, the vane including:

a vane body having an operatively inner end face;

an elongate vane magnet located inside the vane;

characterized in that a longitudinal axis of the elongate vane magnet forms an acute angle relative to the inner end face of the vane body.

According to a further aspect of the invention there is provided a vane magnet, suitable for use in a rotary vane device, the vane magnet being of elongate configuration and having a longitudinal plane extending through a longitudinal axis of the magnet in order to divide the magnet into two elongate halves, wherein two poles of the magnet are located on opposite sides of the longitudinal plane of the magnet. According to a further aspect of the invention there is provided a rotor magnet, suitable for use in a rotary van device, the rotor magnet including: a base section; and

a continuous conical section extending from and around a perimeter of the base section;

wherein one of the poles of the magnet corresponds with the base section, and wherein another of the poles of the magnet corresponds with the conical section.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are described by way of non-limiting examples, and with reference to the accompanying drawings in which:

Figure 1 is an exploded perspective view of a rotor assembly for use in a rotary device in accordance with a first embodiment of the invention;

Figure 2 is a cross-sectional side view of a vane of the rotor assembly of Figure 1 ;

Figure 3 is an exploded perspective view of the rotor and vanes of the rotor assembly of Figure 1 ;

Figure 4 is a side view of a rotor magnet arrangement of the rotor assembly of Figure 1 ;

Figure 5 is a cross-sectional side view of an assembled rotor assembly of Figure 1 ; Figure 6 is a cross-sectional side view of a rotor of the rotor assembly, showing the profile of a vane receiving slot in more detail;

Figure 7 is a schematic cross-sectional side view of another embodiment of part of a rotor assembly in accordance with the invention; and

Figure 8 is a schematic cross-sectional side view of another embodiment of part of a rotor assembly in accordance with the invention.

DETAILED DESCRIPTION OF INVENTION

Referring to the drawings, in which like numerals indicate like features, non limiting examples of rotary devices in accordance with the invention is generally indicated by reference numeral 10.

A first embodiment of the rotor device is described with reference to Figures 1 to 6.

The rotary device 10 comprises a rotor assembly 1 1 that is locatable inside a complementary rotor housing 12. The rotor assembly 1 1 is retained inside the rotor housing 12 by way of two rotor housing end caps 13. The detail design of the components may vary, and are not of importance because the detail design of the rotary device will be dictated by the specific purpose for which the device will be utilized. The principles underlying this invention may, for example, find application in rotary pumps, rotary compressors and rotary engines, provided the particular rotary device does make use of radially displaceable vanes. The rotor assembly 1 1 comprises a rotor body 20 and a plurality of vanes 30 that are slidingly located in the rotor body. The rotor body 20 is of a cylindrical configuration, and is generally circular in cross section. The length and diameter of the body will depend on the cylinder capacity that is required for a particular application. A plurality of elongate receiving slots 22 are provided in the body, with each receiving slot extending generally parallel to a longitudinal axis (L) of the cylindrical body. In this embodiment each receiving slot 22 is radially orientated, with a plane of each receiving slot extending through the middle of the receiving slot therefore intersecting the longitudinal axis of the rotor body 20.

In this particular embodiment six equally spaced apart receiving slots 22 extend radially outwardly from a central zone of the rotor body 20, thus dividing the rotor body 20 into six sectors. In the embodiment shown in Figures 1 to 6 the slots are not of constant depth, but each include a deeper proximal section 22.1 , and shallower distal sections 22.2 at the opposite ends of the proximal section 22.1 , as can be best seen in Figures 5 and 6. The transition of the deeper section 22.1 to the shallower sections 22.2 occurs gradually by way of a tapered or angled intermediate section 22.3, thus forming shoulder sections of reduced depth at the opposite ends of a receiving slot. This configuration enables the use of a larger diameter rotor magnet 23 without significantly reducing the operational depth of the receiving slot on the whole, while at the same time also reducing the distance between a rotor magnet 23 and a complementary profiled vane 31 and vane magnet 33, as is discussed in more detail below.

The rotor body 20 has a core 25 which may be at least partially hollow in order for receiving pockets to be defined at the ends of the hollow core (not shown), or which may include two discrete receiving pockets 24 located in opposite ends of the core 25. In the embodiment shown in Figures 1 to 6, the receiving pockets 24 are in the form of discrete conical apertures (blind apertures) extending inwardly from distal ends of the rotor body 20 towards the proximal zone of the rotor body 20. As mentioned above, in this embodiment, the receiving pockets 24 are in the form of two discrete apertures, but there is no reason why the pockets cannot be in the form of two suitably profiled end zones of an elongate, and at least partially continuous, hollow core that extends longitudinally through the rotor body.

Rotor end sections 80 are removably securable to the distal end zones of the rotor body 20. Each end section 80 includes a flange section 82 that in use abuts the end of the rotor body, and hence seals of the receiving pocket 24, and a shaft section 81 extending from the flange section 82. There is provided for the flange 82 to have apertures 83 extending therethrough, and for complementary threaded apertures 26 to be provided in the rotor body 20, in order for the end sections 80 to be securable to the rotor body 20 by way of threaded securing means.

It is convenient for the shaft 81 of the rotary device 10 to be a separate removable component as opposed to being integrally formed with the rotor body 20, as this allows for the provision of receiving pockets having a diameter larger than the bore that could potentially have been formed in the shaft had the rotor body 20 and shaft 81 been an integral component. It is, however, not inconceivable for the rotor body 20 and the shaft 81 to be integrally formed, with one of the receiving pockets 24 then being located at the end of a hollow bore that extends through the shaft 81 .

It should be noted that the receiving slots 22 do not extend all the way to the receiving pockets 24, but that bottom ends of the receiving slots 22 are separated from the receiving pockets 24 by wall section 28. The rotor body 20 is made from a non-ferrous material in order to reduce the effect of the body 20 on the magnetic field and magnetic flux formed by the rotor magnets.

Rotor magnet arrangements 23 (meaning magnets located in the rotor) are located inside the core 25 of the rotor body 20, and more particularly inside the receiving pockets 24 in the rotor body. It should be noted that in the embodiment shown in Figures 1 to 6, each rotor magnet arrangement in fact only constitutes a single magnet, and the terms‘rotor magnet arrangement’ and‘rotor magnet’ can in theory be used interchangeability. However, it is also foreseen (for example in Figures 7 and 8) for each rotor magnet arrangement to comprise a plurality of separate magnets that acts as a functional unit, and hence the need for the two different terms, i.e. ‘rotor magnet arrangement’ and‘rotor magnet’. The same applies to the terms ‘vane magnet arrangement’ and‘vane magnet’.

In this embodiment, each rotor magnet arrangement comprises a single rotor magnet that is located in each receiving pocket 24, with the rotor magnet 23 and the receiving pocket 24 being complementary configured and dimensioned in order for the rotor magnet 23 snugly to fit inside the receiving pocket 24. In this embodiment, each rotor magnet 23 is of a generally conical configuration, and includes a cylindrical base section 23.1 and a continuous conical section 23.2 extending from, and around a perimeter of, the base section 23.1 . There is provided for one of the poles of the magnet to correspond with the base section 23.1 (and more particular with a base surface of the base section), and for another of the poles of the magnet to correspond with the conical section 23.2 (and more particularly with a conical surface of the conical section). In this particular embodiment, a short cylindrical skirt section 23.3 is provided between the base section 23.1 and the conical section 23.2, with the skirt section 23.3 sharing the polarity of the base section 23.1 .

Each vane 30 is in the form of an elongate and flat body of material 31 configured and dimensioned to fit inside an elongate receiving slot 22. Vane magnet arrangements 33 (meaning magnets located in the vanes) are provided in zones of the vane that will in use be located inside the receiving slot 22. In this embodiment, each vane magnet arrangement 33 is in the form of an elongate cylindrical magnet that is circular in cross section. The elongate vane magnets 33 are located in elongate receiving apertures 32 formed in the body 31 of the vane. It should be noted that the vane magnets need not be circular in cross-section. In fact, it would be preferable for the vane magnets not to be circular in cross-section (for example square or rectangular) as this will ensure that the vane magnets do not rotate in their receiving slots. There is provided for each vane magnet arrangement to include a plurality of elongate cylindrical magnets located end to end, thus defining a functionally singular vane magnet.

One of the important features of this invention is that a plane (M) that divides the vane magnet arrangement into the two polar halves (also referred to as the magnetic equator) is offset relative to the longitudinal axis (L) of the rotor at an acute offset angle (b). In this embodiment, this is achieved by the elongate vane magnets not being configured radially or parallel relative to a longitudinal axis of the rotor body 20, but instead being located at an acute offset angle relative to the longitudinal axis of the rotor body. This therefore means that the vane magnet arrangement 33 is angularly offset relative to an end face 34 of the vane 30. The offset angle (b) is between 20 degrees and 40 degrees, and preferably about 30 degrees. The exact angle is not of critical importance, and more important is that the angle, at least to some extent, corresponds to the angle of the conical section 23.2 of the rotor magnet arrangement.

One vane magnet arrangement 33 is located in each end zone of the vane body 31 . In this embodiment, the end zones of the vane body 31 terminate in shoulder sections 35 that are of reduced height. Each shoulder section includes a tapering section 36 that connects the shoulder sections 35 and the remainder of the body 31 . The tapering section 36 defines a section with a tapered end face 36.1 , which corresponds to the location where the vane magnet arrangement 33 is located. This configuration, coupled with the conical shape 23.2 of the rotor magnet arrangement 23 and the complementary profile of the ends sections 22.3 of the receiving slots 22, therefore results in a decrease of the distance between the rotor magnet arrangement and the vane magnet arrangement. An offset angle (Q) between a rotor magnet arrangement 23 and a corresponding vane magnet arrangement 33 is kept relatively small, for example in the vicinity of between 0 and 5 degrees. The angle is preferably zero degrees in order for the longitudinal axis of the vane magnet arrangement and the plane of the conical surface to be parallel, but may be up to 10 or 15 degrees.

As mentioned above, in this embodiment the vane magnet arrangements 33 are in the form of elongate cylindrical magnets that are circular in cross section. Each vane magnet 33 therefore has a longitudinal axis, with a longitudinal plane (also referred to as the magnetic equator M) extending through the longitudinal axis in order to divide the elongate cylindrical magnet into two elongate halves. The two poles of the magnet are located on opposite sides of the longitudinal plane of the magnet. When viewed from an end of the magnet, two semi-circular halves of the magnet will therefore have opposite polarity. Stated otherwise, the longitudinal axis of the magnet runs through a plane or line dividing the two poles of the vane magnet. This polarity configuration is important, as it increases the effective length of the pole of the vane magnet arrangement that interacts with the opposing pole (i.e. the conical surface 23.2) of the rotor magnet arrangement 23. It has to be emphasized that the vane magnets need not be circular in cross-section, and that they can also be square or rectangular in cross-section, in particular where larger / thicker vanes are used.

The vane magnet arrangements 33 and the rotor magnet arrangements 23 are configured to oppose one another, in order for the vanes to be biased away from the rotor body. In this embodiment, the magnetic field or flux is increased by the following features (separately and collectively):

- the transverse / angled orientation of the vane magnet arrangements inside the vane; - the polarity plane of the vane magnet arrangements being configured to extend along a longitudinal axis of the vane magnets;

- the rotor magnet arrangement having a complementary profile (conical) resulting in the opposing magnets to have the maximum exposure to one another; and

- the slot in the rotor body being configured to complement the shape of the end face of the vane, so as to bring the vane magnet arrangement and the rotor magnet arrangement closer to one another.

The use of the elongate, offset vane magnet arrangements means that the total flux of the vane magnet arrangements can be increased without having the disadvantages associated with radial or parallel vane magnets.

The provision of receiving pockets in the rotor body (instead of just one continuous hollow bore) means that larger rotor magnet arrangements can be utilized, and that the shape of the rotor magnet arrangements can be selected to complement the flux profile of the vane magnet arrangements.

The effect of this configuration is that the magnets provide an increased biasing force, functionally superior to that associated with other magnet arrangements, but without having a detrimental structural impact on the vane strength.

Two further non-limiting variation are depicted schematically in Figures 7 and 8. In Figure 7 the vane and vane magnet arrangements are of identical configuration to that shown in the embodiment of Figures 1 to 6, but conventional cylindrical rotor magnet arrangements 23 are used. In this embodiment, the receiving slot 22 in the rotor body is also similar to that shown in the embodiment of Figures 1 to 6. Figure 8 shows an embodiment similar to that of Figure 7, but in this case the vanes are rectangular and does not include the tapering end sections and shoulders. The slots 22 in the rotor body 20 are also of uniform profile, and do not include the tapering end zones as is shown in Figures 1 to 7. Although these two embodiments are not as advantageous as the embodiment shown in Figures 1 to 6, they still constitute a significant improvement over the prior art because they include the transversely orientated elongate vane magnets having the longitudinal polarity plane, while also having receiving pockets for receiving the rotor magnets in the rotor body.

A further embodiment, not shown in the figures, involves a variation in the configuration of the vane magnet arrangements 33. Instead of an elongate cylindrical magnet (or a plurality of end to end cylindrical magnets), it is also possible to utilize a plurality of short, spaced apart and parallel orientated magnets that are inserted into the vane at a configuration 90 degrees rotated relative to the embodiments shown in the figures. The configuration will therefore be that of a number of adjacent magnets resembling the spokes of a ladder. In such an embodiment the vane magnet arrangement will therefore comprise of a plurality of small magnets that all share the same polarity. In effect, in combination one will still have the polarity and flux similar to that of an elongate magnet with one long pole on one side of a magnetic equator of the composite magnate, and an opposing pole on the other side of the magnetic equator. From a polarity and flux perspective the outcome will be similar to that of the configuration shown in the figures, but from a mechanical perspective this will not be an ideal configuration as the vane will be weakened by the necessary provision of plurality of parallel vane magnet receiving apertures extending orthogonally into the vane.

It will be appreciated that the above are only some embodiments of the invention and that there may be many variations without departing from the spirit and/or the scope of the invention.

Claims

CLAIMS:

1 . A rotor, suitable for use in a rotary device, the rotor including:

a cylindrical rotor body including a plurality of longitudinally extending receiving slots, the cylindrical rotor body having a longitudinal axis;

a plurality of vanes, wherein each vane is slidingly locatable inside a receiving slot; and wherein the vanes are biased away from the cylindrical rotor by way of opposing magnets located in the vanes and the rotor;

the opposing magnets including a vane magnet arrangement located in each end zone of a vane, and an opposing rotor magnet arrangement located at least partially inside a core of the rotor body;

characterized in that a plane dividing a vane magnet arrangement between north and south poles is orientated to form an acute offset angle relative to a longitudinal axis of the rotor body.

2. The rotor of claim 1 wherein the vane magnet arrangement includes one or more elongate magnets having a longitudinal axis that is orientated to form an acute offset angle relative to a longitudinal axis of the rotor body.

3. The rotor of claim 2 wherein the or each elongate magnet has a longitudinal plane extending through a longitudinal axis of the magnet and which divides the magnet into two elongate polar halves, wherein two poles of the magnet are located on opposite sides of the longitudinal plane of the magnet.

4. The rotor of claim 1 , 2 or 3 wherein the offset angle is between 10 degrees and 60 degrees relative to the longitudinal axis of the rotor body, preferably between 20 degrees and 40 degrees, more preferably about 30 degrees.

5. The rotor of any one of claims 1 to 4 wherein the rotor magnet arrangements are located in end zones of the rotor body.

6. The rotor of any one of claims 1 to 5 wherein the rotor magnet arrangements are located inside receiving pockets formed in the ends of the rotor body.

7. The rotor of any one of claims 1 to 6 wherein the rotor magnet arrangements are of at least partially conical or frusto-conical configuration.

8. The rotor of claim 7 wherein each rotor magnet arrangement includes a cylindrical base section, and a conical section extending from and around a perimeter of the base section, wherein one of the poles of the magnet corresponds with the base section, and wherein another of the poles of the magnet corresponds with the conical section.

9. The rotor of claim 7 or 8 wherein an angle between the longitudinal axis of the vane magnet arrangement and the conical section of the rotor magnet arrangement is less than 10 degrees, preferably less than 5 degrees, more preferably less than 2 degrees.

10. The rotor of any one of the preceding claims wherein each vane includes shoulder sections of reduced height at distal ends of the vane, with the vane magnet arrangements located in the shoulder sections.

1 1 . The rotor of claim 10 wherein operatively inners ends of the shoulder sections are of tapering configuration in order to reduce an angle between the longitudinal axis of the vane magnet arrangement and an inner end of the vane.

12. The rotor of any one of claims 10 or 1 1 wherein distal ends of the receiving slots are complementary tapered to the shoulder sections of the vanes in order to reduce the distance between a vane magnet arrangement and a rotor magnet arrangement.

13. A rotor, suitable for use in a rotary device, the rotor including:

a plurality of vanes, wherein a vane is slidingly locatable inside a receiving slot; and wherein the vanes are biased away from the cylindrical rotor by way of opposing magnets located in the vanes and the rotor;

characterized in that the vane magnet arrangements located in the vanes are orientated to form an acute angle relative to a longitudinal axis of the rotor body.

14. A vane, suitable for use in a rotary device, the vane including:

a vane body having an operatively inner end face; an elongate vane magnet located inside the vane; characterized in that a longitudinal axis of the elongate vane magnet forms an acute angle relative to the inner end face of the vane body.

15. A vane magnet, suitable for use in a rotary vane device, the vane magnet being of elongate configuration and having a longitudinal plane extending through a longitudinal axis of the magnet in order to divide the magnet into two elongate halves, wherein two poles of the magnet are located on opposite sides of the longitudinal plane of the magnet.

16. A rotor magnet, suitable for use in a rotary van device, the rotor magnet including:

a base section; and

a conical section extending from and around a perimeter of the base section;