GB2324284A - Traction means for a vehicle - Google Patents

Abstract

A vehicle is fitted with at least one wheel, each wheel having a spindle 109 supporting at least part of the vehicle's weight. The spindle 109 is moveable within the wheel's frame 105 such that the wheel's centre of gravity can be changed. A force F displacing the spindle in a direction substantially opposing gravity will result in the spindle supporting at least part of the vehicle's weight above a surface. The spindle will then be inclined due, at least partly, to gravity to move in a substantially downward direction. The wheel is arranged such that the resulting downward movement of the spindle preferably results in rotation of the wheel's outer frame, thereby providing traction for the vehicle, which may be a wheelbarrow.

Description

TRACTION MEANS Field of the Invention The present invention relates particularly, although not exclusively, to traction means for vehicles.

Background to the Invention Volume of road traffic, particularly, individually owned motor vehicles, has increased dramatically over the past decades and indications show that the level will continue to increase in the years to come. The increasing level of traffic means that levels of exhaust emissions in the atmosphere caused by the vehicles will increase proportionately.

Certain components of exhaust emissions, for example, lead, sulphur dioxide, carbon dioxide, can have serious detrimental consequences with respect to health and the environment. Some experts predict that possible consequences of the increased level of exhaust emissions will result in global warming on a disastrous scale, leading to unstable weather pattems and mass flooding of populated land areas.

Current proposals intended to decrease the amount of harmful vehicle exhaust emissions can be generalised into two categories. Firstly, individual motorists may be dissuaded from using motor vehicles by Govemments imposing heavy taxes or financial penalties upon them. However, a problem associated with such penalties is that motorists are unwilling to sacrifice the convenience and freedom provided by individually owned vehicles. Furthermore, public transport alternatives are regarded by many motorists as being less desirable and inflexible compared to use of a car, and considerable investment may be required by Govemments in order to raise the standards of current public transport services.

A second trend intended to decrease the level of harmful emissions produced by motor vehicles is to use alternative sources of fuel other than diesel and petrol. Examples of such alternative sources of energy include solar, electrical and hydrogen based fuels. However, as yet, a viable alternative has not been made widely available to the public. Furthermore, if such an alternative was to become widespread, it could result in most current vehicles becoming redundant and outmoded or at least requiring significant modification in order to function using an alternative fuel source. Other problems would also need to be addressed, for example, replacing service station facilities currently dispensing petrol and diesel fuels with facilities supplying the alternative energy source. The resulting costs involved in re-designing, marketing and possibly compensating existing vehicle owners on national and global scales could be immense.

Certain proposed changes to existing motor vehicles include having motors running on alternative fuel sources such as batteries when the vehicle is being driven through areas such as city centres where demands on the vehicle's motor for continuous high performance is not as great as on motorways, etc. However, even though such proposals may be less disruptive than completely replacing current petrolldiesel based engines, a considerable amount of modification would still be required to be made to current vehicles' motors and other components.

Summary of the Invention An object of the present invention is to utilise gravitational forces in order to rotate or assist in rotation of wheels. Wheels incorporating preferred embodiments as described hereinbelow may be used to provide traction for vehicles, although it will be appreciated that the present invention is not limited to providing traction means for vehicles and that it may be of benefit in other circumstances where efficient rotation of wheels is desirable, eg turbines for production of energy. The present invention provides a system which is preferably used in conjunction with a force which may be provided by conventional means, for example, an electrical motor or manual operation. A vehicle's weight is at least partly supported by a spindle which is movable within a frame of the vehicle's wheel(s). The spindle may be moved in a direction substantially opposing gravity by the conventional means. Subsequently, a gravitational force may attempt to return the wheel(s) components, including the spindle, to equilibrium and this effect may be utilised in order to provide traction for the vehicle by moving the wheel in a manner resulting in traction for the vehicle. As gravity may partly assist in rotation of the wheel(s), an amount of energy required to rotate the wheel(s) may be less than where the conventional force alone is used for rotation.

A wheel according to one of the embodiments described herein below may be fitted to existing vehicles, this refitting of wheels may be easier to achieve than replacing a vehicle's entire motor and other components, resulting in cheaper modification costs.

According to a first aspect of the present invention there is provided traction means for a vehicle comprising: a wheel having means for supporting at least part of weight of said vehicle, wherein position of said supporting means is movable relative to a frame of said wheel.

Preferably, the supporting means comprises a spindle extending transversely through the wheel.

Preferably, the wheel further comprises an inner hub through which the spindle extends transversely.

Preferably, the wheel further comprises means for allowing the inner hub to rotate in a similar or opposite direction to the wheel frame, possibly by means of a bearing.

Preferably, the traction means may further comprise an electric motor.

Suitably, the electric motor is arranged to rotate the inner hub.

Preferably, the traction means further comprises at least one ram, the ram comprising a telescopic arm which is extendable out of and retractable in to the ram, with one end of the ram being attached to the wheel frame and another end of the ram being attached to the supporting means.

Preferably, the traction means further comprises a locating disc.

Preferably, the telescopic arm of the ram is extendable/retractable by pneumatic, hydraulic, electrical or mechanical means.

According to a second aspect of the present invention, there is provided a wheel incorporating traction means as described herein.

According to a third embodiment of the present invention, there is provided a vehicle incorporating at least one wheel, the wheel being configured as described herein.

According to a fourth aspect of the present invention, there is provided a method of providing traction for a vehicle, the method comprising the steps of: supporting at least part of weight of the vehicle on a spindle extending transversely through a wheel of the vehicle; and moving position of the spindle relative to a frame of the wheel.

Preferably, the method further comprises the step of: allowing substantially gravitational forces to move the spindle.

Preferably, the wheel further comprises an inner hub through which the spindle extends transversely. Preferably, the wheel further comprises means for allowing the inner hub to rotate in a similar or opposite direction to the wheel frame.

Preferably, the spindle is moved by means of an electric motor.

Preferably, the wheel further comprises at least one ram, the ram comprising a telescopic arm which is extendable out of and retractable into the ram, one end of the ram being attached to the wheel frame and another end of the ram being attached to the spindle.

Preferably, the telescopic arm of the ram is extendable/retractable by pneumatic, hydraulic, electrical or mechanical means.

Brief Description of the Drawings For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which: Fig. 1A illustrates a first embodiment of the present invention comprising a wheel, a bearing, an inner hub and a spindle extending through the inner frame; Fig. 1B illustrates changed positions of the components of the wheel illustrated in Fig. 1A after a human operator has exerted a force on the wheelbarrow; Fig. 1C illustrates changed positions of the wheel's components shown in Fig. 1B resulting at least partly from gravitational forces acting upon the wheel's components; Fig. 2 illustrates a second preferred embodiment of the present invention; Fig. 3 illustrates a third preferred embodiment of the present invention; Fig. 4 illustrates a fourth preferred embodiment of the present invention; Fig. 5 illustrates a view through line A-A' of the fourth embodiment of Fig. 4; and Fig. 6A, Fig. 6B and Fig. 6C illustrate an example of operation of the third embodiment of Fig. 3.

Detailed Description of the Best Mode for Carrying Out the Invention There will now be described by way of example the best mode contemplated by the inventors for carrying out the invention. In the following description numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the present invention.

Referring to Fig. 1 of the accompanying drawings, there is illustrated a first embodiment of the present invention. The first embodiment may be a vehicle such as a wheelbarrow which is normally moved over a surface by means of a manual force, usually being pushed by a human operator. The wheelbarrow comprises a substantially conventional load compartment 102 which is attached to a wheel 104 by means of a connecting member 103.

In this specification, by "wheel" it is meant a substantially circular frame or disk comprised of one or more components arranged to revolve, in particular such as to facilitate motion of a vehicle. The wheel frame itself may be in contact with a surface upon which the vehicle is to travel, or may be fitted with, for example, a tyre or caterpillar track, which makes contact with the ground surface.

Alternatively, the wheel frame may be integrated with a tyre, ie. the frame comprises the tyre. Wheel 104 comprises a substantially circular outer frame 105 which may be manufactured from any one of a variety of materials, eg, wood, metal, plastic, rubber or a mixture of materials. Wheel 104 further comprises an inner hub 106. Inner hub 106 is substantially circular and has a smaller diameter than outer frame 105, the hub being positioned within the outer frame 105 such that a centre of the hub 106 and a centre of the outer frame 105 are located in a substantially equal position. In the first embodiment, inner hub 106 is housed within outer frame 105 such that a bearing 107 located between hub 106 and outer frame 105 and can allow the hub 106 to rotate in a similar or opposite direction to outer frame 105. Inner hub 106 may be considered to rotate about a central point 108, the central point 108 being common to the hub 106 and the outer frame 105. Outer frame 105 and inner hub 106 may be fitted with a ratchet or a device which engages when the inner hub and outer frame rotate to a certain angle1 such that after a pre-determined angle of rotation the inner hub and outer frame are, in effect, connected together and rotate in an identical direction until another pre-set angle of rotation where the ratchet/engaging device no longer connects the inner hub and outer frame. Central point 108 may be thought of as an axis about which inner hub 106 rotates. It will be appreciated by those skilled in the art that bearing 107 (and corresponding components of the other preferred embodiments described herein below) may be replaced by any other device or means which allows the inner hub to rotate in a similar or opposite direction to the outer frame.

In an alternative embodiment to the first embodiment illustrated in Fig 1A, a hub may not be housed within the outer frame but rather the hub may be located to a side of the outer frame, and may be connected to the wheel by means of, for example, cog wheels extending from sides of the outer frame bearing and the hub or a bearing between the outer frame and the hub.

In the embodiment illustrated in Fig 1A, the connecting member 103 which connects the load 102 and wheel 104 is attached to inner hub 106 of the wheel by means of a spindle 109. The spindle 109 is preferably a strong bar made out of a rigid material such as metal. The spindle 109 extends transversely, preferably substantially perpendicularly, through inner hub 106. Spindle 109 may be fixed through inner hub 106 but is preferably free to rotate and may act as an axle for the wheel and supports at least part of the wheelbarrow's weight. The spindle 109 preferably has a length greater than a thickness of inner hub 106 and other components of wheel 104, such that ends of the spindle 109 protrude beyond surfaces of inner hub 106, thereby allowing connecting member 103 to be attached to wheel 104 whilst allowing the hub 106 and other components of the wheel 104 to rotate. Thus, at least part of a weight of the wheelbarrow, including weight of load 102 and connecting means 103, may be attached to and supported by spindle 109 of wheel 104. As spindle 109 supports at least part of the weight of the wheelbarrow, moving the position of the spindle within wheel 104 may effect the wheel's centre of gravity (a point through which the weight supported may be considered to act). Spindle 109 is located away from the centre of the inner hub 106, preferably at a point near the inner hub's perimeter/circumference. As spindle 109 extends through inner hub 106, which may rotate independently of outer frame 105, the spindle 109 is, in effect, moveable within outer frame 105 of wheel 104, ie the spindle is repositionable radially, vertically and/or horizontally relating to the outer frame of the wheel and a surface with which the wheel may be in contact.

In order to provide further flexibility with respect to the spindle's moveability relative to the outer frame of the wheel, an alternative to the first embodiment illustrated in Fig 1A may incorporate a slot in the wheel's hub, the slot extending from near its central point in a substantially straight line to near the wheel's hub's perimeter/circumference. The slot is preferably wide enough so that an end of the spindle can protrude out of the slot to allow it to be connected to the wheelbarrow. This alternative first embodiment further comprises means for moving the spindle along the slot such that the end of the spindle may be substantially fixed in a certain position along a length of the slot. The means for adjusting the position of the spindle along the slot may comprise a rod connected to a piston, one end of the piston being attached to a piston motor preferably near the hub's centre. The piston motor preferably moved the rod and one end of the rod is attached to the spindle. Thus, the piston motor can adjust the spindle's position along the slot. This repositionability of the spindle along the slot means that the spindle can be adjusted so that it may be positioned at any point along a radius of the hub, from its central point to near the hub's perimeter/circumference. As the slot allows the spindle to be positioned such that it may extend substantially perpendicularly through the central point of the hub, the spindle may thus act as a substantially conventional axle for the wheel, i.e, extending perpendicularly through a central point of the wheel.

Spindle 109 may be located nearer a perimeter/circumference of wheel 104 for example by increasing the diameter of inner hub 106 and decreasing area of outer frame 105 such that the spindle is further away from central point 108 and nearer to the perimeter/circumference of wheel 104. Spindle 109 may be thought of as an axle through wheel 104 which supports at least part of the weight of the wheelbarrow. Having spindle 109 located nearer the circumference/perimeter of wheel 104 may result in more efficient operation of the first embodiment (as described herein below) if surface 101 is inclined.

In Fig. 1A, wheel 104 of the wheelbarrow is shown as being in contact with a surface 101. For the purpose of illustrating the first preferred embodiment, surface 101 is a substantially horizontal ground surface, although it will be understood that the surface may be uneven or inclined. For the purposes of illustrating operation of the first embodiment, wheel 104 may be thought of as being in contact with surface 101 at a point A in Fig. IA, point A being located on surface 101 immediately beneath central point 108 of wheel 104. In the example of Fig. 1A, the load 102 and connecting member 103 of the wheelbarrow are located to the right of point A. Spindle 109 is aligned substantially directly beneath central point 108 and above point A in Fig. 1A, i.e. the spindle and inner hub 106 may be thought of as being at equilibrium and the wheel's centre of gravity may be considered to be a substantially vertical line extending through a diameter of wheel 104, through its central point 108 to point A on surface 101.

The human operator of the wheelbarrow would normally be located to the right of load 102, providing a force in a substantially right to left direction, typically by firstly lifting load compartment 102 of the wheelbarrow so that the only part of the wheelbarrow in contact with the surface 101 is part of the outer frame 105 of wheel 104. The human operator would then push the wheelbarrow (usually by means of handles connected to load compartment 102) in a right to left direction (relative to Fig. 1A).

Referring to Fig. 1B of the accompanying drawings, there is illustrated changed positions of components of Fig. 1A such as may typically occur after the human operator of the wheelbarrow has exerted a substantially right to left force upon the wheelbarrow. The direction of the force (F) is generally indicated by left arrow 110. Force F is transmitted along the wheelbarrow, along connecting member 103 to wheel 104. As force F is exerted upon the wheelbarrow, the outer frame 105 of wheel 104 may rotate in an anti-clockwise motion (illustrated by arrow 113) such as to provide traction (ie draw the vehicle along a surface) for the wheelbarrow along surface 101 in a right to left direction such that the wheelbarrow moves so that central point 108 of its wheel 104 reaches a point which is substantially directly above a point labelled B, ie, the wheelbarrow has been moved over a distance A to B (denoted by left arrow 111). Force F may also result in movement of inner hub 106. Force F may result in rotation of inner hub 106 in a clockwise direction (illustrated by arrow 112), thereby displacing spindle 109 from a location substantially above point A in Fig. 1A through an arc of an angle denoted by O so that spindle 109 moves horizontally to a point right of point B and also vertically a distance upwards (i.e. in a direction substantially opposing gravity) relative to its position illustrated in Fig. 1A. It will be appreciated by those skilled in the art that dampening or suspension devices may be incorporated into wheel 104 and/or connecting member 103 in order to minimise or eliminate vertical movement of load compartment 102. Thus, at least part of the wheelbarrow's weight may be considered to be suspended above surface 101 by spindle 109, which, due to substantially gravitational forces, can lead to an imbalance when force F is decreased or ceased. Thus, the wheel's components as shown in Fig. 1B may not be considered to be at equilibrium and the wheel's centre of gravity may be considered to be located to the left of its central point 108 due to the spindle's position.

Refening to Fig. 1C of the accompanying drawings, there is illustrated changed positions of the components of Fig. 1B which may result, at least partly, due to gravitational forces acting upon the weight of the wheelbarrow's components to' attempt to retum them to equilibrium. Due at least partly to a gravitational force (g) acting in a substantially downward direction (illustrated by downward arrow 117), spindle 109 supporting at least part of weight of the wheelbarrow will be inclined to move in a substantially downward direction. Due to the spindle's attachment to inner hub 106, the inner hub 106 may rotate in an anti-clockwise direction (illustrated by arrow 116) through an arc of an angle substantially equal to angle e of Fig. 1B, thus, displacing spindle 109 (which supports at least part of the wheelbarrow's weight) in horizontal and vertical directions. Bearing 108 is preferably arranged such that the rotation 116 of the inner hub 106 may be transferred to outer frame 105, resulting in the outer frame 105 and thereby wheel 104 rotating in an anti-clockwise direction (illustrated by arrow 115), thus providing traction over surface 101 for the wheelbarrow in a substantially right to left direction.

A substantially right to left force being exerted by the human operator of the wheelbarrow may also continue to be exerted, thus, providing further traction over surface 101 for the wheelbarrow. The rotation of the wheel preferably results in a further right to left movement of the wheelbarrow to a point C (illustrated in Fig. 1C on surface 101 directly beneath the changed position of central point 108 of wheel 104 and also directly beneath the changed position of spindle 109). Thus, the gravitational forces acting upon the components of wheel 104 may, at least partly, result in an overall displacement of the wheel 104 (and thereby the other components of the wheelbarrow) from point B to point C (located to the left of point B) over a distance B to C denoted by left arrow 114.

The resulting traction caused at least partly by gravitational forces may result in the wheelbarrow (or any other vehicle incorporating one or more wheels arranged substantially similar to the first embodiment) moving an additional distance over that which may normally result from force F being exerted on a wheelbarrow having a substantially conventional wheel arrangement (wherein connecting member 103 would be attached to a fixed central axle of a wheel's outer frame), thereby providing greater efficiency (i.e. greater displacement in a substantially horizontal direction) in terms of effort/force required to move the vehicle. The friction occurring between the wheel's components may further give increased stability (compared with a conventional wheel arrangement) to a vehicle on inclined surfaces. This friction may be particularly useful in decreasing a risk of a vehicle (e.g, a wheelbarrow or pram) incorporating the first embodiment 'running away' on an inclined surface.

It will be understood that the distances A to B and B to C and the angle 0 will vary according to various factors, including magnitude and direction of force F exerted upon the vehicle, the weight of the vehicle's components, the dimensions of the vehicle's wheel (such as the diameter of inner hub 106 and outer frame 105), friction occurring between the inner hub and outer frame on bearing 107, as well as variations in surface 101 and even gravitational forces. Thus, Fig. 1A, Fig. 1B and Fig. 1C of the accompanying drawings may be thought of as a preferably ordered sequence of illustrations wherein spindle 109 is substantially at equilibrium in Fig. 1A, the spindle 109 is then shown moved through an arc of angle 0 in Fig. 1B to a vertical distance (such that the components of wheel 104 are not at equilibrium) above its position in Fig. 1A wherein gravitational forces may at least partly move the wheel's components back through angle 0 to be substantially at equilibrium in Fig. 1C, resulting in rotation of wheel 104 and thereby substantially horizontal displacement of the wheelbarrow, thereby allowing the sequence of movement illustrated in Fig. 1A to Fig. 1B to Fig. 1C to be repeated.

Referring to Fig. 2 of the accompanying drawings, there is illustrated a second preferred embodiment of the present invention. The second embodiment comprises a wheel 201. The wheel 201 comprises a substantially circular outer frame 202 and an inner hub 203. The arrangement of the outer frame 202 and the inner hub 203 is substantially similar to that of the first embodiment, i.e. both the inner hub and the outer frame have a common central point (central point 204) and the inner hub 203 is of smaller diameter than outer frame 202 and the inner hub 203 is housed within the outer frame 202 with preferably a cavity 205 existing between the inner hub 203 and outer frame 202. In the cavity 205 of the wheel 201, at least one cog or drive wheel may be positioned, for example drive wheels 207 and 208. Central point 204 may be thought of as a point about which inner hub 203 revolves. Diameters of the drive wheels are preferably equal in size to the gap 205 existing between the inner hub 203 and outer frame 202 such that rotation of the inner hub 203 may cause the drive wheels to rotate and in turn the rotation of the drive wheels may be transferred to outer frame 202, possibly causing it to rotate. Similarly, rotation of the outer frame 202 may cause the drive wheels to rotate, which in tum, may rotate the inner hub 203.

In the example of Fig. 2, one of the drive wheels, drive wheel 207, is preferably attached to an electric motor 209. The motor 209 may be attached to a component of wheel 201, for example, inner hub 203, or the motor 209 may be attached to a part of a vehicle incorporating wheel 201. It will be appreciated that more than one drive wheel may be attached to more than one electric motor, however, in the example of Fig. 2, the two further drive wheels 208 are not attached to motor 209 but may aid in transmitting rotation between inner hub 203 and outer frame 202.

Similar to the first embodiment, a spindle 206 extends transversely, and preferably substantially perpendicularly, through inner hub 203. Spindle 206 may be fixed through inner hub 203 but is preferably free to rotate and may act as an axle for the wheel. A vehicle incorporating the second embodiment is preferably attached to at least one wheel such as wheel 201 by means of spindle 206 in each wheel. Thus, a weight of the vehicle may be supported, at least partly, by spindle(s) 206. Spindle 206 is located away from the centre of the inner hub 203, preferably at a point near the inner hub's perimeter/circumference.

As spindle 206 extends through inner hub 203, which may rotate independently on outer frame 202, the spindle 206 is, in effect, moveable within outer frame of wheel 201, i.e, the spindle is repositionable radially, vertically and/or horizontally relative to the outer frame of the wheel and a surface with which the wheel may be in contact.

In operation, electric motor 209 preferably causes drive wheel 207 to rotate.

Where drive wheel 207 is arranged so that it causes inner hub 203 to rotate, spindle 206 extending through inner hub 203 will be moved accordingly. For example, if drive wheel 207 is rotated by motor 209 in an anti-clockwise direction, inner hub 203 will rotate in a clockwise direction. Thus, comparing positions of components of the second embodiment in operation with the components of the first embodiment illustrated in Fig. 1A, rotating drive wheel 207 will move spindle 206 through an arc in an anti-clockwise direction and in effect substantially upward (opposing gravity), resulting in spindle 206 supporting at least part of the vehicle's weight in a vertical position such that components of wheel 201 are not at equilibrium (compare with Fig. 1B). Comparing with Fig. 1 C, spindle 206 may retum to a position which is at equilibrium due at least partly to gravitational forces, thus, spindle 206 of inner hub 203 may rotate under gravity in a clockwise direction back through an arc which may thereby rotate outer frame 202 in an anti-clockwise direction, providing traction for the vehicle. Drive wheels 208 of wheel 201 may be arranged such that when spindle 208 retums to equilibrium due at least partly to gravity by rotating inner hub 203 in an anti-clockwise direction. Drive wheels 208 may turn in a clockwise direction, resulting in anticlockwise rotation of outer frame 202, moving the vehicle over a surface in a right to left direction.

Thus, gravitational forces may provide additional rotation to the wheel, greater than that which may result from a motor rotating a conventional wheel arrangement. Furthermore, the rotation of the wheel due at least partly to gravity may also be used to charge, for example, a battery which may be connected to motor 209, thus re-charging the motor using energy derived from the gravitational force acting upon spindle 206 and rotating components of wheel 201. The motor 209 may be configured such that the second embodiment is only used in certain circumstances, eg in a city centre, and that a vehicle's conventional motor may be used to drive the wheels in other circumstances, eg on a motorway.

Fig. 3 of the accompanying drawings illustrates a third preferred embodiment of the present invention. The third embodiment comprises a wheel 301. Wheel 301 comprises an outer frame 302 and an inner hub 303. The arrangement of the outer frame 302 and the inner hub 203 is similar to that of the first embodiment, i.e. the inner hub and outer frame have a common central point (central point 312) and the inner hub 303 is of smaller diameter than outer frame 302 and the inner hub 303 is housed within outer frame 302 with preferably a bearing 304 existing between the inner hub and outer frame, which can allow the inner hub 303 and outer frame 302 to rotate in similar or opposite directions.

Similar to the first and second embodiments, a spindle 305 extends transversely, and preferably substantially perpendicularly, through inner hub 303.

Spindle 305 may be fixed through inner hub 303 but is preferably free to rotate and may act as an axle for the wheel. A vehicle incorporating the third embodiment is preferably attached to at least one wheel such as wheel 301 by means of spindle 305 in each wheel. Thus, the weight of the vehicle may be supported, at least partly, by spindle(s) 305.

Wheel 301 further comprises at least one ram, and preferably a first ram 306, a second ram 307 and a third ram 308. Each ram is preferably attached to an inner surface (i.e a surface facing central point 312 of the wheel) of a circumferencelperimeter of outer frame 302 at points preferably equidistant from each other upon the perimeter/circumference, i.e. each ram is attached to the perimeter/circumference of outer frame 302 at a point 1200 away from the other two rams.

The three rams 306, 307 and 308 comprise of substantially identical components. Ram 306 comprises attachment means 309, which connects the first ram 306 to the outer frame 302 and allows components of the first ram 306 to rotate or pivot about attachment means 309. Ram 306 further comprises an extendible /retractable member, comprising arm base 310 one end of which is connected to attachment means 309. The arm base 301 preferably comprises a substantially tubular member of fixed length into which is fitted a substantially tubular telescopic arm 311. A diameter of telescopic arm 311 is less than a diameter of arm base 310 such that telescopic arm 311 may fit into base arm 310, thereby allowing telescopic arm 311 to extend out of and retract into arm base 310. One end of telescopic arm 311 may be adapted such that the arm cannot extend beyond a certain length in order to prevent it escaping from arm base 310. Another end of telescopic arm 311 of the first ram 306 is preferably attached to spindle 305 of the inner hub 303. Thus, as the inner hub 303 rotates, thereby moving spindle 305 radially, telescopic arm 311 may extend or retract out of arm base 310 accordingly and the first ram 306 may pivot about attachment means 309. Similarly, the second and third rams, 307 and 308 each comprise attachment means, arm base and telescopic arm components substantially identical to corresponding components of first ram 306 and one end of the telescopic arms of the second and third rams are also preferably attached to spindle 305 in a similar manner to the first ram 306.

The rams 306, 307 and 308 may be adapted to act as pistons, using pneumatic, hydraulic or other means to extend/retract each ram's telescopic arm out of/into each ram's base arm, thereby causing spindle 305 of inner hub 303 to move. Spindle 305 is preferably located away from the centre of the inner hub 303, preferably at a point near the inner hub's perimeter/circumference. As spindle 305 extends through inner hub 303, which may rotate independently of outer frame 302, the spindle 305 is, in effect, moveable within outer frame 302 of the wheel 301, i.e, the spindle is repositionable radially, vertically and/or horizontally relative to the outer frame of the wheel and a surface with which the wheel may be in contact. An example of operation of the third embodiment will be described with reference to Fig. 6A, 6B and 6C herein below.

Referring to Fig. 4 of the accompanying drawings, there is illustrated a fourth preferred embodiment of the present invention. The fourth embodiment comprises a wheel 400. Wheel 400 comprises an outer frame 410, around which may be fitted a tyre 401. Similar to the third embodiment, outer frame 410 may have one or more rams attached to an inner surface of its circumference/perimeter. Preferably, a first ram 402, a second ram 403 and a third ram 404 are attached to outer frame 410 at equidistant points upon outer frame 410. The rams of the fourth embodiment are substantially similar to the rams used in the third embodiment, for example, first ram 402 comprises attachment means 405 connected to one end of an arm base 406. A telescopic arm 407 may extend out of and retract into base arm 406 of first ram 402.

Attachment means 405 preferably functions as a pivot for the first ram 402. One end of the telescopic arm 407 of first ram 402 is preferably attached to a spindle 408 of the wheel. Similarly, second and third rams 403 and 404 each comprise an extendible/retractable telescopic arm on end of which is attached to spindle 408.

Spindle 408 extends transversely, and preferably substantially perpendicularly, through wheel 400. Spindle 408 may be fixed through the wheel but is preferably free to rotate and may act as an axle for the wheel. A vehicle incorporating the fourth embodiment is preferably attached to at least one wheel, such as wheel 400, by means of a spindle 408 in each wheel. Thus, the weight of the vehicle may be supported, at least partly, by spindle(s) 408.

Wheel 400 further comprises a locating disk 409, through which spindle 408 preferably extends. Spindle 408 may be fixed through locating disc 409 or may be free to rotate. The locating disc 409 comprises a circular disc frame having a central point through which spindle 408 preferably extends.

As rams 402, 403 and 404 are connected to the spindle 408 extending through locating disc 409, extending /retracting one or more of the rams may result in movement of the spindle 408 (and thus locating disc 409) within the outer frame 410 of wheel 400, i.e spindle 408 (and locating disc 409) is repositionable radially, vertically and/or horizontally relative to the outer frame of the wheel and a surface with which the wheel may be in contact. Outer frame 410 preferably comprises an opening 411. For clarity, in Fig 4 the outer frame 410 is transparent such that rams 403, 404 and 405 may be shown. Opening 411 may be substantially triangular shaped and preferably allows ends of spindle 408 to protrude beyond a surface of outer frame 410.

Extending/retracting the rams 403, 404 and 405 such that the arms of the rams are substantially of equal length will typically result in spindle 408 being located in a substantially central position relative to outer frame 401. Having spindle 408 located in such a substantially central position may allow the spindle acting as a central axle through the wheel (substantially similar to a conventional wheel).

Fig. 5 of the accompanying drawings illustrates a view through line A-A' of Fig. 4. Spindle 408 is shown extending substantially perpendicularly through locating disc 409. The spindle 408 may also extend through one or more bearings 403, the bearings located at/near opposite ends of the spindle 408, preferably at locations on the spindle which extend beyond surfaces of outer frame 410. Spindle 408 may also comprise at least one duct 501. In the third and fourth embodiment, spindle 408 preferably comprises an empty cylinder or tube, such that air/gas or liquid may be forced through the spindle 408 by a pump or compressor for example, causing the rams to extend/retract, thereby moving the spindle. It will, however, be appreciated by those skilled in the art that other means including mechanical or electrical arrangements, could be used to extend/retract the rams. The ducts 501 may allow air/gas/liquid to enter and/or leave spindle 408. In the third and fourth embodiment, the point at which the rams are attached to the spindle (spindle 305 in the third embodiment, spindle 408 in the fourth embodiment) preferably comprises sealing device 502. The sealing device 502 is preferably configured so that air/gas/liquid entered into spindle 408 via duct 501 may only enter one or more of the wheel's rams. The sealing device 502 may further comprise mechanical, electronic or other device for selecting which of the rams attached to the spindle may extend/retract.

Alternatively, one or more of the rams may comprise a device which controls when the telescopic arms are to extend out of /retract into their arm bases.

Alternatively, such a controlling device may be fitted to a vehicle incorporating one or more wheel(s) 400.

Where pneumatic means are used to extend the rams of the third or fourth embodiment, sealing device 502 may be configured to prevent the rams extendingiretracting in certain circumstances. For example, when a vehicle incorporating wheel 301 or 400 is travelling downhill, the rams may be prevented from extending/retracting. In the case of the third embodiment, this can cause friction due to inner hub 303 not being able to rotate freely. As air within the rams may be forced out of the rams when the rams are not allowed to extend/retract, the forced air may be used to replenish the compressor's air supply, thus possibly avoiding having to replenish the air supply using another energy source.

Figs. 6A, 6B and 6C of the accompanying drawings illustrate an example of operation of the third embodiment of the present invention. It will be appreciated by those skilled in the art, that the fourth embodiment may operate in a substantially manner to the third embodiment taking into account differences between the third and fourth embodiment's components, such as the inner hub and bearing 304 of the third embodiment being replaced by the locating disc 409 of the fourth embodiment.

In Fig. 6A, wheel 301 is shown as being in contact with a surface 600. For the purposes of illustrating the operation, surface 600 is a substantially horizontal ground surface, although it will be understood that the surface may uneven or inclined. For the purposes of the example, wheel 301 may be thought of as being in contact with surface 600 at a point A in Fig. 6A, point A being located on surface 600 substantially immediately beneath central point 311 of the wheel 301.

Spindle 305 is located substantially directly beneath central point 311 in Fig. 6A, and directly above point A i.e, the spindle and inner hub 303 of wheel 301 may be thought of as being at equilibrium and the wheel's centre of gravity may be thought of as a substantially vertical line extending through a diameter of wheel 301 through central point 311 through point A on surface 600. In the example of Fig. 6A, the attachment means of ram 308 is located substantially directly above central point 311 (and spindle 305) on the inner surface of the wheel's outer frame 302. In Fig. 6a, the attachment means of ram 306 is located at a point on the inner surface of outer frame 302 1200 away from the attachment means of ram 308, thus being located to the right of spindle 305 and being nearer to ground surface 600 than the attachment means of ram 38. In Fig. 6A, the attachment means of ram 307 is located at the point on the inner surface of outer frame 302 1200 from the attachment means of ram 308, thus being located to the left of spindle 305 and being nearer to the ground surface 600 than the attachment means of ram 308.

Referring to Fig. 6B of the accompanying drawings, there is illustrated changed positions of component of Fig. 6A such as may typically occur during operation of the third (or substantially the fourth) embodiment. Ram 306 has extended its telescopic arm, thereby moving spindle 305 within outer frame 302 of wheel 301. Movement of spindle 305 normally results in rotation of inner hub 303. As the telescopic arm of ram 306 in the example of Fig. 6B has in effect pushed spindle 305 to a position to the left and upwards relative to its position in Fig. 6A, inner hub 303 would typically move in a clockwise direction (illustrated by arrow 602). The resulting rotation of inner hub 303 means that spindle 305 has moved radially through an arc, resulting in spindle 305 supporting at least part of the vehicle's weight in a position substantially to the left and vertically above the spindle's position in Fig. 6A. The movement resulting from the extending of the telescopic arm of ram 306 may result in movement of wheel 301 along surface 600, due to displacement of the wheel's components and thus its centre of gravity. In Fig. 6B, the movement is shown as resulting in anti-clockwise rotation of outer frame 302, providing traction for the wheel along surface 601 to a point B (lying substantially directly beneath central point 311 of the wheel), located to the left of point A, resulting in substantially horizontal displacement of wheel 301 over a distance A to B (illustrated by left arrow 601). Alternatively, depending upon various factors, for example, dimensions and mass of the wheel's components, outer frame 302 of wheel 301 may not in fact be displaced horizontally by the extending of the telescopic arm of ram 306. Thus, the wheel's components as shown in Fig. 6B may not be considered to be at equilibrium and the wheel's centre of gravity may be considered to be located to the left of its central point 311 due to the spindle's position.

Referring to Fig. 6C of the accompanying drawings, there is illustrated changed positions of the components of Fig. 6B which may result, at least partly, due to gravitational forces acting upon the weight of a vehicle supported, at least partly, by spindle 305 of wheel 301. Due at least partly to gravitational force (g) acting in a substantially downward direction ( illustrated by downward arrow 607), spindle 305 supporting at least part of the weight of the vehicle will be inclined to move in a substantially downward direction. Due to the spindle's attachment to inner hub 303, the inner hub 303 may rotate through an arc in an anti-clockwise direction (illustrated by arrow 605), thereby displacing spindle 305 in horizontal and vertical directions resulting in spindle 305 being located downwards of its position shown in Fig. 6B. The rotation 605 of inner hub 303 may be transferred (by means of bearing 305) to outer frame 302, thus causing the outer frame 302 to also rotate in an anti-clockwise direction (illustrated by arrow 606). The resulting rotation 606 of outer frame 302 may provide traction over surface 600 for the wheel 301 (and thereby any vehicle incorporating the wheel) such that the wheel's central point may be considered to have moved in a substantially horizontal direction so that its central point 311 lies substantially directly above a point C located to the left of point B over a distance B to C (illustrated by left arrow 604). The position of components of wheel 301 shown in Fig. 6c may be considered to be such that the wheel's components are at equilibrium and that the wheel's centre of gravity may be considered to be a vertical line passing through the wheel's diameter, through central point 311 down to point C.

The rotation of the inner hub 303 and outer frame 302 of wheel 301 will result in movement of the rams 306, 307 and 308 whose ends are attached to the spindle 305 of inner hub 303 and the inner surface of outer frame 302. In Fig.

6C, the wheel's position of equilibrium has resulted in the attachment means of ram 306 being substantially directly above spindle 305, the attachment means of ram 307 being 1200 away from the attachment means of ram 306 therefore lying to the right of spindle 305 and nearer to surface 600 than ram 306. The attachment means of ram 308 is 1200 away from the attachment means of ram 306, therefore located to the left of spindle 305 and nearer surface 600 than ram 306.

Preferably, ram 307 will extend its telescopic arm so that the sequence of changed positions illustrated in Fig. 6A, Fig. 6B and Fig. 6C may be repeated in order to provide continuing traction for the vehicle, considering that ram 307 in Fig. 6C is in a substantially similar position to ram 306 in Fig. 6A. Likewise, ram 306 in Fig. 6C is in a substantially similar position to ram 308 in Fig. 6A and ram 308 in Fig. 6C is in a substantially similar position to ram 307 in Fig. 6A. Thus, in order provide continuing traction in a right to left direction for wheel 301, the ram whose attachment means is located to the right of central point 311 will usually extend its telescopic arm in order to move the wheel's components in a manner which is intended to result in rotation of the outer frame 302 in an anti-clockwise direction, thereby drawing the wheel (and thereby a vehicle incorporating the wheel) over surface 600 in a right to left direction. It will be appreciated that other rams could be extended in order to provide traction for the wheel in an opposite direction, ie, a ram whose attachment means is located substantially to the left of central point 311 and near ground surface 600 may extend its telescopic arm in order to move the wheel's components in a manner intended to result in clockwise rotation of outer frame 302, thereby drawing the wheel over surface 600 in a left to right direction. Rams whose attachment means are located in different locations on the inner surface of the outer frame's circumference/perimeter may extend their telescopic arms if the wheel is positioned on a surface which is inclined or uneven.

Claims (30)

Claims:

1. Traction means for a vehicle comprising: a wheel having means for supporting at least part of a weight of said vehicle, wherein position of said supporting means is moveable relative to a frame of said wheel.

2. Traction means according to claim 1, wherein said supporting means is moveable in a horizontal direction relative to said frame.

3. Traction means according to claim 1 or 2, wherein said supporting means is moveable in a vertical direction relative to said frame.

4. Traction means according to any one of claims 1 to 3, wherein said supporting means comprises a spindle extending transversely through said wheel.

5. 5. Traction means according to claim 4, wherein said wheel further comprises an inner hub through which said spindle extends transversely.

6. Traction means according to claim 5, wherein said hub is housed within said frame.

7. Traction means according to claim 5 or 6, wherein said hub is located to a side of said frame.

8. Traction means according claim 7, further comprising means for allowing said hub to rotate in a similar or opposite direction to said wheel frame.

9. Traction means according to claim 7, wherein said means for allowing opposite or similar rotation comprises a bearing.

10. Traction means according to any one of the above claims, further comprising an electric motor.

11. Traction means according to claim 10, wherein said electric motor is arranged to rotate said hub.

12. Traction means according to any one of claims I to 8, further comprising at least one ram, said ram comprising a telescopic arm which is extendable out of and retractable into said ram, one end of said ram being attached to said wheel frame and another end of said ram being attached to said supporting means.

13. Traction means according to claim 11, further comprising a locating disc.

14. Traction means according to claim 11, wherein said telescopic arm of said ram is extendable/retractable by pneumatic means.

15. Traction means according to claim 11, wherein said telescopic arm of said ram is extendable/retractable by hydraulic means.

16. Traction means according to claim 11, wherein said telescopic arm of said ram is extendable/retractable by electrical means.

17. Traction means according to claim 11, wherein said telescopic arm of said ram is extendable/retractable by mechanical means.

18. A wheel incorporating traction means according to any one of the above claims.

19. A vehicle incorporating at least one wheel, said wheel having traction means according to any one of claims 1 to 16.

20. A method of providing traction for a vehicle, said method comprising the steps of: supporting at least part of weight of said vehicle on a spindle extending transversely through a wheel of said vehicle; and moving position of said spindle relative to a frame of said wheel.

21. A method according to claim 20, further comprising the step of: allowing substantially gravitational forces to move said spindle.

22. A method according to claim 21, wherein said wheel further comprises an inner hub through which said spindle extends transversely.

23. A method according to claim 22, wherein said wheel further comprises means for allowing said inner hub to rotate in a similar or opposite direction to said wheel frame.

24. A method according to any one of claims 20 to 23, wherein said spindle is moved by means of an electric motor.

25. A method according to any one of claims 20 to 23, wherein said wheel further comprises at least one ram, said ram comprising a telescopic arm which is extendable out of and retractable into said ram, one end of said ram being attached to said wheel frame and another end of said ram being attached to said spindle.

26. A method according to claim 25, wherein said telescopic arm of said ram is extendable/retractable by pneumatic means.

27. A method according to claim 25, wherein said telescopic arm of said ram is extendable/retractable by hydraulic means.

28. A method according to claim 25, wherein said telescopic arm of said ram is extendable/retractable by electrical means.

29. A method according to claim 25, wherein said telescopic arm of said ram is extendable/retractable by a mechanical means.

30. Traction means for a vehicle substantially as described herein with reference to the accompanying drawings.