GB2581260A

GB2581260A - Radial conveyor with multi-mode wheel assembly

Info

Publication number: GB2581260A
Application number: GB1919147.7A
Authority: GB
Inventors: Bratton Terence; Mawhinney Mark
Original assignee: Terex GB Ltd
Current assignee: Terex GB Ltd
Priority date: 2017-05-26
Filing date: 2017-05-26
Publication date: 2020-08-12
Anticipated expiration: 2037-05-26
Also published as: GB2581260B; GB201919147D0

Abstract

A radial conveyor 10 has a chassis with a longitudinal axis and a wheel assembly on the chassis, preferably assemblies 30A, 30B located at each side of the chassis. Each wheel assembly 30A, 30B is movable with respect to the chassis between a non-deployed state and a deployed state. In the non-deployed state wheel assemblies 30A, 30B have rotational axes perpendicular to the longitudinal axis, which may allow them to support transport of the radial conveyor. In the deployed state the rotational axes are radially spaced from the longitudinal axis; typically the wheels may then support radial movement of the conveyor. Wheel assemblies 30A, 30B are also raisable and lowerable with respect to the chassis, which may allow the ground clearance of the chassis and the overall height of conveyor 10 to be adjusted, as well as facilitating transition between operating modes. A jack (58, Figure 5) may also be provided on each side of the chassis.

Description

Radial Conveyor with Multi-Mode Wheel Assembly

Field of the Invention

The present invention relates to radial conveyors.

Background to the Invention

Radial conveyors comprise a conveyor mounted on a wheeled support structure wherein the wheels 10 are configured to allow the conveyor to move in a radial, or arc-like, manner about a centre point. Some radial conveyors include a second set of wheels to facilitate transport of the conveyor. The provision of two sets of wheels increases the cost and complexity of the conveyor.

It would be desirable to provide an improved radial conveyor.

Summary of the Invention

The invention provides a radial conveyor apparatus comprising: a chassis having a longitudinal axis; a conveyor supported on the chassis; at least one wheel assembly coupled to the chassis, the or each wheel assembly comprising at least one wheel coupled to a wheel support structure for rotation about a rotational axis, wherein said at least one wheel assembly is movable with respect to the chassis between a non-deployed state, in which said rotational axis is perpendicular with the longitudinal axis of the 25 chassis, and a deployed state in which said rotational axis is radially displaced with respect to said longitudinal axis; and wherein said at least one wheel assembly is operable to raise and lower said at least one wheel with respect to the chassis.

Preferably said at least one wheel assembly is pivotably coupled to said chassis for pivoting movement between said deployed and non-deployed states. Said at least one wheel assembly is preferably pivotably coupled to said chassis for pivoting movement between said deployed and non-deployed states about an axis that is, in-use, perpendicular with a ground surface on which said radial conveyor apparatus is supported.

Said at least one wheel assembly may be pivotably coupled to said chassis for pivoting movement relative to said chassis to raise and lower said at least one wheel with respect to the chassis. Preferably said at least one wheel assembly is pivotably coupled to said chassis for pivoting movement in a plane that is, in use, perpendicular with a ground surface on which said radial conveyor apparatus is supported.

Preferably, said wheel support structure is pivotably coupled to said chassis for pivoting about at least one pivot axis, said at least one wheel being spaced apart from said at least one pivot axis.

In preferred embodiments. one end of said wheel support structure is pivotably coupled to said chassis for pivoting about at least one pivot axis. the other end being coupled to said at least one wheel.

Said at least one pivot axis typically includes at least one axis that is, in use, perpendicular with a ground surface on which said radial conveyor apparatus is supported.

Said at least one pivot axis may include at least one axis that is, in use, parallel with a ground surface on which said radial conveyor apparatus is supported.

In preferred embodiments said wheel support structure comprises at least one extendible support 15 member that is operable to raise and lower said at least one wheel with respect to the chassis. Preferably said wheel support structure is configured so that extension and retraction of the extendible support member causes the wheel assembly to pivot with respect to the chassis.

Preferably, said at least one extendible support member is coupled between said chassis and said at 20 least one wheel. More preferably said at least one extendible support member has one end pivotably coupled to said chassis.

In preferred embodiment said at least one extendible support member comprises a powered actuator for effecting extension and retraction of said at least one extendible support member. Conveniently 25 said powered actuator comprises a hydraulic ram.

Said at least one extendible support member may include a strut coupled to said actuator. Said actuator may be pivotably coupled to said strut. Said actuator may be pivotably coupled to said chassis. Said strut may be coupled to said at least one wheel.

Preferably, said wheel support structure comprises a single extendible support member.

In preferred embodiments said wheel support structure comprises a frame or linkage, said at least one extendible support member being part of said frame or linkage Said frame or linkage may comprise an upper support member and a lower support member, one of said upper or lower support members comprising said extendible support member, the other of said upper of lower support members being of fixed length.

Typically. said at least one wheel assembly is coupled to a side of said chassis. Preferably a 40 respective one of said at least one wheel assemblies is provided at each side of the chassis.

Preferred embodiments include at least one jack operable into and out of a ground-engaging state in which it supports, in use, said chassis on a ground surface. Preferably a respective jack is provided at each side of the chassis.

Further advantageous aspects of the invention will be apparent to those ordinarily skilled in the art upon review of the following description of a specific embodiment and with reference to the accompanying drawings.

Brief Description of the Drawings

An embodiment of the invention is now described by way of example and with reference to the accompanying drawings in which: Figure 1A is a perspective view of a radial conveyor apparatus embodying the invention, the 15 apparatus being shown in a use mode; Figure 1B is an enlarged view of a multi-mode wheel assembly being part of the apparatus of Figure 1A and being shown in a radial mode; Figure 2A is a perspective view of the apparatus of Figure 1 shown in a transport mode; Figure 2B is an enlarged view of the multi-mode wheel assembly shown in a transport mode; Figure 3 is a side view of part of the apparatus of Figure 1A showing the multi-mode wheel assembly 25 in the transport mode in a ground-engaging state and in a relatively raised position; Figure 4 is a side view of part of the apparatus of Figure 1A showing the multi-mode wheel assembly in the transport mode and in the ground-engaging state in a relatively lowered position; Figure 5 is a side view of part of the apparatus of Figure 1A showing the multi-mode wheel assembly in the transport mode and the ground-engaging state, and also illustrating the deployment of a jack; Figure 6 is a side view of part of the apparatus of Figure 1A showing the multi-mode wheel assembly in a non-ground engaging state and in a relatively raised position, and showing the jack in a ground 35 engaging state; Figure 7 is a perspective view of the multi-mode wheel assembly in deployment between its transport and radial modes; and Figure 8 is a perspective view of the apparatus showing the multi-mode wheel assembly in the radial mode.

Detailed Description of the Drawings

Referring in particular to Figures 1, 1A, 2 and 2A. there is shown a radial conveyor apparatus 10 embodying the invention. The conveyor apparatus 10 is of a general type commonly referred to as "radial conveyors". The conveyor apparatus 10 comprises a conveyor 12, which is typically but not necessarily an extendible conveyor. The conveyor 12 is supported by a wheeled support structure 14. In preferred embodiments, the support structure 14 comprises a chassis 16 and a conveyor support 18 extending between the chassis 16 and the conveyor 12 to support the conveyor 12 with 10 respect to the chassis 16. The conveyor support 18 is preferably extendable in order to adjust the position of the conveyor 12 with respect to the chassis 16, in particular to raise or lower the height of the conveyor 12.

The conveyor 12 has a feed end 20 and a discharge end 22. A hopper 24 may be provided at the feed end 20 for loading material (not shown) onto the conveyor 12. In use. the conveyor 12 receives material at the feed end 20 and conveys the material to the discharge end 22 to be discharged to a desired location, e.g. a stockpile or a material processing apparatus (not shown).

The feed end 20 of the conveyor 12 is pivotably coupled to the chassis 16 such that the discharge end 22 is raised or lowered as the conveyor 12 pivots with respect to the chassis 16. Typically, the conveyor 18 is coupled to the chassis 16 at a first end 17 of the chassis 16. The pitch of the conveyor 12 with respect to the chassis 16 is determined by the length of the conveyor support 18, which is preferably extendible/retractable to hold the conveyor 16 at any one of a plurality of different pitches thereby raising or lowering the height of the discharge end 22.

The conveyor support 18 has one end pivotably coupled to the chassis 16, the other end pivotably coupled to the conveyor 12 and is extendible in the end-to-end direction to allow the conveyor 12 to pivot with respect to the chassis 16. The conveyor support 18 is lockable in any one of a plurality of states of relative extension/retraction in order to support the conveyor 12 at a desired pitch with respect to the chassis 16. In the illustrated embodiment the conveyor support 18 is coupled to the chassis 16 at a second end 19 of the chassis 16 opposite the end 17 at which the conveyor 18 is coupled to the chassis. Alternatively, the conveyor support 18 may be coupled to the chassis 16 at any other location spaced apart (along the longitudinal axis of the chassis) from the location at which the conveyor 18 is coupled to the chassis 16. In the illustrated embodiment the conveyor support 18 is coupled to the conveyor 12 at a location between the feed and discharge ends 20, 22. Alternatively, the conveyor support 18 may be coupled to the conveyor 12 at any other location spaced apart (along the longitudinal axis of the conveyor) from the feed end 20 of the conveyor 12. The conveyor support 18 may take any suitable form, for example comprising a frame (as illustrated) and/or one or more support members. Conveniently, the conveyor support 18 is telescopically extendible.

The conveyor 12 may be extendible/retractable by virtue of comprising at least one foldable conveyor portion. In the illustrated embodiment: the conveyor 12 has a base conveyor portion 12A (which includes the feed end 20) hinged to a foldable conveyor portion 12B. The foldable portion 12B can be folded between a deployed state (Figure 1A) for use and a folded state (Figure 2A) for storage and transport. Any conventional folding mechanism (e.g. comprising hydraulic ram(s) coupled to a linkage) may be provided to effect folding and unfolding of the foldable portion 12B. In this example, the conveyor support 18 is coupled to the conveyor 12 at the end of the base portion 12A opposite the feed end 20. In alternative embodiments the conveyor 12 may be telescopically extendible.

The chassis 16 carries a first set of one or more ground-engaging wheel assemblies 24, typically being located at the first end 17 of the chassis 16. In the illustrated example, first and second track type wheel assemblies 24A, 24B are provided although in alternative embodiments one or more simple (non-track) wheels may be used.

The chassis 16: and therefore the conveyor 12, is pivotable about an in-use vertical axis (i.e. an axis that is perpendicular with the ground surface upon which the apparatus 10 is supported). This vertical axis is typically located at the first end 17 of the chassis 16. To this end, in the illustrated embodiment: the first end 17 of the chassis 16 is pivotably coupled to the wheel assemblies 24A: 248. Hence: the chassis 16 and conveyor 12 are able to pivot relative to the wheel assemblies 24A, 248 about a vertical axis at the first end 17. This pivoting movement may be referred to as radial movement.

First and second multi-mode wheel assemblies 30A: 308 are coupled to the chassis 16, one on either side of the chassis 16 (with respect to the longitudinal axis of the chassis 16). In the illustrated embodiment, each wheel assembly 30A, 30B comprises a pair of wheels rotatable about a common axis. More generally each wheel assembly 30A, 30B comprises one or more wheels (which may optionally be of the track type). The wheel assemblies 30A, 30B are spaced apart from the wheel assemblies 24A, 24B along the longitudinal axis of the chassis 16. Conveniently, the wheel assemblies 30A: 308 are coupled to the chassis 16 at its second end 19. The wheel assemblies 30A, 3013 facilitate the radial movement of the chassis 16 as is described in more detail hereinafter. The wheel assemblies 30A, 30B are preferably provided in a manner such that they mirror each other, or are at least capable of mirroring each other: with respect to the longitudinal axis of the chassis 16. Conveniently, the wheel assemblies 30A, 30B are the same as each other (other than to the extent that they may in some respects be mirror images of each other to account for their location on opposite sides of the chassis 16). Accordingly any descriptions herein of either one of the wheel assemblies 30A, 30B applies to the other. Moreover, while it is preferred to provide a respective one of the wheel assemblies 30A, 30B on each side of the chassis 16, it is possible in alternative embodiments to provide a wheel assembly 30A, 30B on only one side.

The conveyor apparatus 10 is operable between a use mode (Figure 1A) and a transport mode (Figure 2A). In the use mode, the conveyor 12 typically extends obliquely upwards with respect to the longitudinal axis of the chassis 16, with its feed end 20 at a relatively low level (typically at or adjacent chassis-level) and its discharge end 22 at a relatively raised level. The height of the discharge end 22 and the pitch of the conveyor 12 are determined by the conveyor support 18, and can be increased or decreased by changing the length of the conveyor support 18. Where applicable, the conveyor 12 is extended or unfolded in the use mode.

In the transport mode, the conveyor 12 is moved closer to the chassis 16 than when in the use mode, preferably being located on top of the chassis 16 and extending substantially parallel with the longitudinal axis of the chassis 16. Where applicable, the conveyor 12 is retracted or folded in the transport mode.

The wheel assemblies 30A, 30B are each operable between a radial mode (Figures lA and 1B) and a transport mode (Figures 2A and 2B). In the radial mode, the wheel assemblies 30A, 30B facilitate the radial movement of the chassis 16. To this end, the rotational axis of each wheel assembly 30A, 30B is radially displaced from the longitudinal axis of the chassis 16. In the transport mode of the wheel assemblies 30A, 30B, the rotational axis of each wheel assembly 30A, 30B is perpendicular with the longitudinal axis of the chassis 16 to facilitate movement of the chassis 16, and therefore of the apparatus 10, in the longitudinal direction. Accordingly, in the transport mode, the apparatus 10 is amenable to being towed or pushed, or even of being driven in cases where it is self-propelled.

To effect the radial and transport modes, the wheel assemblies 30A, 30B are movable with respect to the chassis 16 between a deployed state (Figures lA and 1B) and a non-deployed state (Figures 2A and 2B). Preferably, each wheel assembly 30A, 30B is pivotably coupled to the chassis 16 to allow it to pivot between its deployed and non-deployed states about an in-use vertical axis. Each wheel assembly 30A, 30B comprises one or more wheels 32 rotatably mounted on a wheel support structure 34. The wheel support structure 34 is pivotably coupled to the chassis 16 to allow the wheel assembly 30A, 30B to pivot between the deployed and non-deployed states about an in-use vertical axis. Typically, one end 33 of the wheel support structure 34 is coupled to the chassis 16 while the wheel(s) 32 are mounted on its opposite end 35. In the deployed state the wheel support structure 34 projects outwardly away from the chassis 16 (typically extending obliquely to the longitudinal axis of the chassis) to hold the wheel(s) 32 at a location that is laterally spaced apart from the respective side of the chassis 16 (and such that their rotational axis is radially displaced from the longitudinal axis of the chassis 16). In the non-deployed state the wheel support structure 341s folded alongside the chassis 16 (typically extending parallely or substantially parallely to the longitudinal axis of the chassis) to locate the wheel(s) 32 adjacent the respective side of the chassis 16 such that their rotational axis is perpendicular with the longitudinal axis of the chassis 16. A respective recess 36 may be provided in each side of the chassis 16 for receiving the wheel(s) 32 in the non-deployed state. The wheel support structure 34 may be coupled to the chassis 16 at the mouth of the respective recess 36.

In addition to being pivotable between the deployed and non-deployed states, the wheel support structure 34 is also pivotable with respect to the chassis 16 about at least one horizontal axis to allow the wheel(s) 32 to be raised and lowered with respect to the chassis 16. As such the wheel(s) 32 may be said to be height-adjustable with respect to the chassis 16. Raising and lowering the wheel(s) 32 causes the chassis 16 to be lowered and raised, respectively, with respect to the ground surface. Preferably, the wheel assembly 30A. 30B can be raised or lowered with respect to the chassis 16 to adopt any one of a plurality of positions in which the wheel(s) 32 are correspondingly raised or lowered and in which the chassis 161s correspondingly lowered or raised with respect to the ground surface on which it is supported. In any of these positions the wheel(s) 32 are still ground-engaging and so facilitate transport of the apparatus 10. It is further preferred that the wheel assemblies 30k 30B can be raised with respect to the chassis 16 to at least one position in which the wheel(s) 32 do not engage the ground (typically such that the lowest level of the wheel(s) 32 is higher than the lowest level of the chassis). Hence, the wheel assembly 30k 30B can be raised or lowered with respect to the chassis 16 between a ground-engaging state and a non ground-engaging state. It is preferred that, in the ground engaging state, the wheel assembly 30A, 30B can adopt more than one position in which its height differs with respect to the chassis 16 in order that the chassis can be supported by the wheel(s) 32 at more than one height with respect to the ground surface.

In the preferred embodiment the wheel support structure 34 is provided with at least one extendible support member 40 for raising and lowering the wheel assembly 30A, 30B. The arrangement is such that extension or retraction of the support member 40 causes the wheel assembly 30k 30B to pivot in a vertical plane with respect to the chassis 16. In preferred embodiments, the wheel support structure 34 comprises upper and lower support members 40, 42, each for example comprising a strut, each support member 40, 42 having one end 44, 46 pivotably coupled to the chassis 16 for pivoting about a respective horizontal axis. This allows the wheel assembly 30A. 30B to be raised and lowered as described. The other end 48,50 of the support member 40, 42 is coupled to the wheel(s) 32. The ends 44,46 are also pivotably coupled to the chassis 16 for pivoting about a vertical axis to allow movement of the wheel assembly 30A, 30B between the deployed and non-deployed states. The extendible support member 40 comprises a linear actuator 52 (conveniently a hydraulic ram) to effect extension and retraction of the member 40. In the illustrated example, the extendible support member 40 also includes a strut portion 54 to which the actuator 52 is coupled, preferably pivotably. In particular one end (e.g. the butt) of the actuator 52 is pivotably coupled to the chassis 16 the other end (e.g. the extendible end, in this case the piston rod) being coupled to one end of the strut portion 54, the other end of the strut portion 54 being coupled to the wheel(s) 32. The lower support member 42 is of fixed length.

It will be understood that many variations of the wheel support structure 34 are feasible. For example, the extendible support member 40 may be the lower support member rather than the upper support member. Alternatively or in addition, the linear actuator may serve as the extendible support member without being coupled to any strut portion 54. Alternatively or in addition each support member may be extendible. More generally the wheel support structure may comprise any framework or linkage having at least one extendible member that is operable to raise and lower the wheel(s) 32 in the manner described. Preferably the, or each, extendible member is extendible by powered means, e.g. hydraulically or electrically, and so may comprise at least one powered actuator.

Referring now in particular to Figures 3 to 8, exemplary operation of the conveyor apparatus 10 is described. Only wheel assembly 30A is shown in Figures 3 to 7 but the same description applies to 10 the other wheel assembly 30B.

Figure 3 shows the apparatus 10 in its transport mode. The wheel assembly 30A is in its transport mode. As such it is in its non-deployed state, extending alongside the chassis 16 such that the rotational axis of the wheels 32 is perpendicular with the chassis 16. The wheels 32 are in a ground-engaging state and so facilitate transport of the apparatus 10 as a road-going vehicle. Typically the apparatus 10 is towed in the transport mode, although it may alternatively be pushed, or include any conventional propulsion system to allow self-propulsion.

Referring to Figure 4, the apparatus 10 and wheel assembly 30A are still in the transport modes and so the same description applies as provided for Figure 3. However, in comparison with Figure 3, the wheel assembly 30A, and therefore the wheels 32, is in a relatively lowered position compared to the relatively raised position of Figure 3. In each case, the wheels 32 are in a ground engaging state and so, in the arrangement of Figure 4, the lowered wheel assembly 30A raises the chassis 16 relative to the ground surface in comparison with the arrangement of Figure 3 which holds the chassis 16 in a relatively lowered position. The different arrangements shown in Figures 3 and 4 are effected by controlling the extension of the extendible support 40, which in this case involves extending or retracting the actuator 52, to pivot the wheel assembly 30A about its ends 44, 46 in a vertical plane.

By controlling the height position of the wheels 32 (for example as illustrated in Figures Sand 4), the ground clearance of the chassis 16 can be adjusted to suit the transport requirements of the conveyor apparatus 10 in the transport mode. It will be understood that the wheel assembly 30A may be operable to adopt any one of a plurality of different height positions (not just the two illustrated in Figures 3 and 4) to correspondingly adjust the ground clearance of the chassis 16. Adjusting the ground clearance not only is helpful for negotiating variations in the ground surface, but also for adjusting the overall height of the conveyor apparatus 10, especially in the transport mode where height restrictions may be encountered. The ability to raise and lower the wheels also facilitates moving the wheel assemblies between the deployed and non-deployed states as is described in more detail hereinafter.

Figures 5 to 8 illustrated how the wheel assemblies 30A, 30B may be operated from their transport mode to their radial mode. In Figures, the wheel assembly 30A is in its transport mode and the same description applies as is provided for Figures 3 and 4. It is preferred that the wheel assembly 30A is in a relatively lowered position in comparison to the position adopted for normal transport (e.g. the position of Figure 4 rather than the position of Figure 3). In any event, the wheels 32 are ground-engaging. A jack 56 is coupled to the chassis 16 and is operable to engage with the ground surface to support the chassis 16, and therefore the conveyor apparatus 10, on the ground surface. Preferably a respective jack 56 is provided on each side of the chassis 16, as can be seen in Figure 8, and the same description may be applied to each jack 56. The jack 56 has a deployable jacking leg 58 that is extendable from a base 60 between a non ground-engaging state (Figure 5) and a ground-engaging state (Figures 6 and 7). The jack 56 is operated from its non ground-engaging state into its ground-engaging state while the wheels 32 are ground engaging (Figure 5). Then, with the jack 56 in its ground-engaging state, the wheel assembly 30A is operated from its ground-engaging state to its non ground-engaging state by raising the wheels 32 off the ground (Figure 6). This is effected by retracting the extendable member 40, which in this embodiment involves retracting the actuator 52.

The jack 56 is preferably manually operable although in alternative embodiments it may be power-operated. To hold the jack 56 in its ground-engaging state any suitable locking mechanism may be provided, for example a locking pin and socket arrangement. As illustrated, a plurality of spaced apart locking pin sockets may be provided to allow adjustment of the extension of the leg 58 in the ground-engaging state, which in turn affects the ground clearance of the chassis 16 when supported by the jack 56.

When the chassis 16 is supported by the deployed jacks 56 and the wheel assemblies 30A, 30B are in the non ground-engaging state, the wheel assemblies 30A, 30B may be moved between the transport and radial modes, i.e. between the non-deployed and deployed states. In preferred embodiments, movement of the wheel assemblies 30A, 30B between the deployed and non-deployed states is effected manually by pivoting the assemblies 30A, 30B about the vertical axis at the ends 44. 46. In alternative embodiments, one or more powered actuators (e.g. hydraulic ram(s)) may be provided for this purpose.

Figure 7 shows the wheel assembly 30A in the deployed state while the jack 56 is in the ground-engaging state. The wheels 32 are still non ground-engaging to facilitate the pivoting movement of the wheel assembly 30A between its deployed and non-deployed states.

With reference in particular to Figure 8, while the jacks 56 are in the ground-engaging state and the wheel assemblies 30A, 30B in their deployed and non ground-engaging states, the wheel assemblies 30A, 30B are lowered into their ground-engaging state. Then the jacks 56 are operated into their non ground engaging states. The wheel assemblies 30k 30B are now in their radial mode and the conveyor apparatus 10 is in the use mode. The height of the wheel assemblies 30A, 30B may be adjusted as previously described to obtain the desired ground clearance for the radial mode.

A reverse operation may be implemented to operate the wheel assemblies 30A. 30B from the radial mode to the transport mode, and so to operate the conveyor apparatus 10 from the use mode to the transport mode: starting with the configuration of Figure 8 (radial mode), the jacks 56 are deployed to the ground-engaging state, after which the wheel assemblies 30A, 30B are raised to the non ground-engaging state. Then the wheel assemblies 30A, 30B are moved to the non-deployed state and lowered into the ground-engaging state, after which the jacks 56 are operated to the non ground-engaging state. The height of the wheel assemblies 30A, 30B may be adjusted as previously described to obtain the desired ground clearance for the transport mode.

It will be apparent from the foregoing that the wheel assemblies 30k 30B are operable in multiple modes to support transport and radial use of the conveyor apparatus 10 without the requirement for separate wheel sets for use and transport. Moreover, in preferred embodiments, the wheel assemblies are relatively simple and therefore inexpensive. In particular, each wheel assembly 30A, 30B may require only one powered component (the actuator 52).

The invention is not limited to the embodiment(s) described herein but can be amended or modified without departing from the scope of the present invention.

Claims

CLAIMS: 1. A radial conveyor apparatus comprising: a chassis having a longitudinal axis; a conveyor supported on the chassis; at least one wheel assembly coupled to the chassis, the or each wheel assembly comprising at least one wheel coupled to a wheel support structure for rotation about a rotational axis, wherein said at least one wheel assembly is movable with respect to the chassis between a non-deployed state, in which said rotational axis is perpendicular with the longitudinal axis of the 10 chassis, and a deployed state in which said rotational axis is radially displaced with respect to said longitudinal axis; and wherein said at least one wheel assembly is operable to raise and lower said at least one wheel with respect to the chassis.
2. The apparatus as claimed in any preceding claim further including at least one jack operable into and out of a ground-engaging state in which it supports, in use, said chassis on a ground surface, and wherein, preferably, a respective jack is provided at each side of the chassis.
3. The apparatus of claim 2, wherein said apparatus is operable in a use mode, in which said at least one wheel assembly is in said deployed state and said at least one jack is not in said ground engaging state, or in a transport mode, in which said at least one wheel assembly is in said non-deployed state and said at least one jack is not in said ground engaging state, or in a transition mode, in which said at least one jack is in said ground-engaging state to allow said at least one wheel assembly to move between said deployed state and said non-deployed state.
4. The apparatus of any preceding claim, wherein said at least one wheel assembly is pivotably coupled to said chassis for pivoting movement between said deployed and non-deployed states, and wherein, preferably, said at least one wheel assembly is pivotably coupled to said chassis for pivoting movement between said deployed and non-deployed states about an axis that is, in-use, perpendicular with a ground surface on which said radial conveyor apparatus is supported.
5. The apparatus of any preceding claim, wherein said at least one wheel assembly is pivotably coupled to said chassis for pivoting movement relative to said chassis to raise and lower said at least one wheel with respect to the chassis, and wherein, preferably, said at least one wheel assembly is pivotably coupled to said chassis for pivoting movement in a plane that is, in use, perpendicular with a ground surface on which said radial conveyor apparatus is supported.
6. The apparatus of claim 4 or 5, wherein said wheel support structure is pivotably coupled to said chassis for pivoting about at least one pivot axis, said at least one wheel being spaced apart from 40 said at least one pivot axis.
7. The apparatus of any one of claims 4 to 6, wherein one end of said wheel support structure is pivotably coupled to said chassis for pivoting about at least one pivot axis, the other end being coupled to said at least one wheel.
8. The apparatus of claim 6 or 7, wherein said at least one pivot axis includes at least one axis that is, in use, perpendicular with a ground surface on which said radial conveyor apparatus is supported.
9. The apparatus of any one of claims 6 to 8, wherein said at least one pivot axis includes at least one axis that is, in use, parallel with a ground surface on which said radial conveyor apparatus is 10 supported.
10. The apparatus of any preceding claim wherein said wheel support structure comprises at least one extendible support member that is operable to raise and lower said at least one wheel with respect to the chassis.
11. The apparatus of claim 10 when dependent on any one of claims 5 to 9, wherein said wheel support structure is configured so that extension and retraction of the extendible support member causes the wheel assembly to pivot with respect to the chassis.
12. The apparatus of claim 10 or 11, wherein said at least one extendible support member is coupled between said chassis and said at least one wheel.
13. The apparatus of claim 12, wherein said at least one extendible support member has one end pivotably coupled to said chassis.
14. The apparatus of any one of claims 10 to 13, wherein said at least one extendible support member comprises a powered actuator for effecting extension and retraction of said at least one extendible support member, and wherein, preferably, said powered actuator comprises a hydraulic ram.
15. The apparatus of claim 14, wherein said at least one extendible support member further includes a strut coupled to said actuator.
16. The apparatus of claim 15, wherein said actuator is pivotably coupled to said strut.
17. The apparatus of claim 15 or 16, wherein said actuator is pivotably coupled to said chassis.
18. The apparatus as claimed in any one of claims 15 to 17, wherein said strut is coupled to said at least one wheel.
19. The apparatus of any one of claims 10 to 189, wherein said wheel support structure comprises a single extendible support member.
20. The apparatus of any one of claims 10 to 19. wherein said wheel support structure comprises a 5 frame or linkage, said at least one extendible support member being part of said frame or linkage.
21. The apparatus of claim 20, wherein said frame or linkage comprises an upper support member and a lower support member, one of said upper or lower support members comprising said extendible support member, the other of said upper of lower support members being of fixed length.
22. The apparatus of any preceding claim wherein said at least one wheel assembly is coupled to a side of said chassis.
23. The apparatus of any preceding claim wherein a respective one of said at least one wheel 15 assemblies is provided at each side of the chassis.
24. The apparatus of any preceding claim, wherein, when said at least one wheel assembly is in said non-deployed state, said at least one wheel assembly is folded alongside said chassis to locate said at least one wheel adjacent a side of the chassis.
25. The apparatus of claim 24. wherein said chassis is shaped to define a recess for receiving said at least one wheel when said at least one wheel assembly is in said non-deployed state.