GB2547126A

GB2547126A - Conveyor assembly and method of manufacturing the same

Info

Publication number: GB2547126A
Application number: GB1704604.6A
Authority: GB
Inventors: Toye Edward
Original assignee: Conveyor Units Ltd
Current assignee: Conveyor Units Ltd
Priority date: 2013-03-13
Filing date: 2013-03-13
Publication date: 2017-08-09
Anticipated expiration: 2033-03-13
Also published as: GB2511788A; GB201304492D0; GB2547126B; GB201704604D0; GB2511788B

Abstract

A wheel conveyor 10, with an associated method of manufacture, is configured so that a spanning member 24 is moveable relative to side mounts 34,28, so as to engage them. Wheel spindle 14 is moveable relative to, and engageable with, a formation 32. In particular the wheel spindle 14 may be displaceable vertically so as to engage with the formation 32. In this manner, with the formation 32 open / accessible to the mounting of the spindle 14 in one go, the spindle 14 need not be threaded through multiple apertures and wheels 18 during manufacture. Also disclosed is a wheel conveyor, or method of making such,

Description

Title: Conveyor assembly and method of manufacturing the same Description of Invention

This invention relates to a conveyor assembly for a conveyor, and more specifically for use in the type of conveyors known as gravity ‘skate wheel’ conveyors. The invention also relates to a method of constructing a conveyor assembly.

Unpowered conveyors provide an economical and simple means by which goods may be transported. Minimal effort is required to move goods whether by manual assistance or under gravitational force (i.e. when the conveyor is inclined from horizontal, known as a ‘gravity’ conveyor). Unpowered conveyors of the type known as skate wheel conveyors provide rows of small wheels (‘skate wheels’) spaced from one another along the length of the conveyor. In this way, the spaced skate wheels provide a conveying surface over which packages, or the like, may be conveyed. A problem with such known conveyors is that they are time-consuming to manufacture. Traditional methods of manufacturing skate wheel conveyors require each spindle to be fed through a plurality of skate wheels so as to form an axle. The axle is supported relative to the conveyor by a plurality of axle support brackets, each providing an aperture through which the spindle passes, so that the skate wheels are supported between adjacent axle support brackets by the axle. The axle support brackets are connected at their lower ends to a support structure that spans the width of the conveyor and is connected to either side of the conveyor frame.

Whilst feeding the spindle through the central apertures of the skate wheels, between each pair of adjacent skate wheels the end of the spindle must be fed through an aperture of an axle support bracket. This requires the skate wheels, spindle, support element and attached axle support brackets to be assembled in one location. The skate wheels must be held in position between the axle support brackets, as the spindle is fed through the apertures in the wheels and axle support brackets. This process is time consuming and labour intensive, and requires that the spindle, skate wheels, and axle support parts are all assembled in situ during both manufacturing and repair processes.

According to an aspect of the invention we provide a conveyor assembly including: an axle formation comprising an elongate spindle supporting a plurality of wheels; a pair of side mounts for disposal on opposite sides of a conveyor and each having a mounting formation for supporting an end portion of the spindle; and an axle support comprising a spanning member disposed, in use, across substantially the width of the conveyor between the side mounts, and a support bracket extending, in use, substantially upwards from the spanning member, the support bracket having a support formation for supporting a portion of the spindle, wherein the support formation is configured such that the axle formation is moveable relative to the support formation so as to engage the support formation in a direction substantially perpendicular to the axis defined by the spindle axle support, such that a portion of the spindle is supported by the support formation.

According to an aspect of the invention we provide a conveyor assembly including: an axle formation comprising an elongate spindle supporting a plurality of wheels; a pair of side mounts for disposal on opposite sides of a conveyor and each having a mounting formation for supporting an end portion of the spindle; and an axle support comprising a spanning member disposed, in use, across substantially the width of the conveyor between the side mounts, and a support bracket extending, in use, substantially upwards from the spanning member, the support bracket having a support formation for supporting a portion of the spindle, wherein each side mount includes a holding formation configured to receive an end portion of the spanning member such that the axle support is moveable relative to the side mounts between an unsupported position in which the axle support is not supported by the side mounts, and a supported position in which the axle support is supported by the side mounts.

The axle formation may be moveable from an un-mounted position in which the axle formation is not supported by the side mounts, to a mounted position in which each end of the axle formation is supported by a mounting formation of a respective side mount.

The conveyor assembly may further include a retaining member having a receiving formation for receiving a portion of the spindle and a first securing formation for securing the retaining member to a support bracket.

The receiving formation may be an aperture defined by the retaining member.

The support bracket may include a second securing formation for cooperation with a respective first securing formation of a retaining member.

The first securing formation and the second securing formation may both be apertures, the conveyor assembly further including a securing element for insertion through the apertures of the first and second securing formations when aligned with one another.

The first securing formation may be releasably securable to the support bracket.

Each side mount may include a holding formation configured to receive an end portion of a spanning member.

Each holding formation may comprise a substantially U-shaped channel for supporting an end portion of a spanning member.

In use the holding formation may substantially prevent lateral movement of the spanning member perpendicular to its axis and relative to the holding formation.

The conveyor assembly may comprise a plurality of support brackets. A conveyor may include a plurality of conveyor assemblies.

According to an aspect of the invention we provide a method of manufacturing a conveyor assembly, comprising the steps of: locating a plurality of wheels on an elongate spindle to form an axle formation; providing a pair of side mounts each having a mounting formation for supporting an end portion of the spindle; providing an axle support comprising a spanning member which, in use, is disposed across substantially the width of the conveyor between the side mounts, and a support bracket, the support having a support formation for supporting a portion of the spindle; and engaging the axle formation with the support formation by moving the axle formation relative to the support formation in a direction substantially perpendicular to the axis defined by the spindle, such that a portion of the spindle is supported by the support formation.

Providing a pair of side mounts may comprise providing a pair of side mounts each having a mounting formation for supporting an end portion of the spindle and each having a holding formation for receiving an end portion of a spanning member, the method further comprising the step of: moving the axle support from an unsupported position in which the axle support is not supported by the side mounts to a supported position in which each end of the spanning member is received by a holding formation such that the axle support is supported by the side.

The step of moving the axle support to a supported position may occur before the step of engaging the axle formation with the support formation, such that during engagement of the axle formation with the support formation, the axle formation is moved from an un-mounted position in which the axle formation is not supported by the side mounts to a mounted position in which each end of the axle formation is supported by a mounting formation of a respective side mount.

The step of moving the axle support to a supported position may occur after the step of engaging the axle formation with the support formation, such that during movement of the axle support to the supported position, the axle formation is moved from an un-mounted position in which the axle formation is not supported by the side mounts to a mounted position in which each end of the axle formation is supported by a mounting formation of a respective side mount.

According to an aspect of the invention we provide a method of manufacturing a conveyor assembly, comprising the steps of: locating a plurality of wheels on an elongate spindle to form an axle formation; providing a pair of side mounts each having a mounting formation for supporting an end portion of the spindle and each having a holding formation for receiving an end portion of a spanning member; providing an axle support comprising a spanning member and a support bracket, the support having a support formation for supporting a portion of the spindle; and moving the axle support relative to the side mounts from an unsupported position in which the axle support is not supported by the side mounts to a supported position in which each end of the spanning member is received by a holding formation such that the axle support is supported by the side mounts.

Moving the axle support to the supported position may further comprise engaging each end portion of the spanning member with a holding formation of a respective side mount.

Engaging an end portion of the spanning member with a respective holding formation may include positioning the end portion of the spanning member so that it is supported by a U-shaped channel comprised by the holding formation, such that lateral movement of the spanning member perpendicular to its axis and relative to the holding formation is substantially prevented.

Locating the plurality of wheels on the elongate spindle to form an axle formation may further comprise feeding the spindle through central apertures defined by the wheels.

Locating the plurality of wheels on the elongate spindle to form an axle formation may further comprise locating one or more spacer elements on the spindle, the or each spacer element comprising a sleeve configured to encircle a portion of the spindle between adjacent wheels.

Locating the plurality of wheels on the elongate spindle to form an axle formation may further comprise locating a retaining member on the spindle, the or each retaining member having a receiving formation for receiving a portion of the spindle and a first securing formation for securing the retaining member to a support bracket.

Locating the or each retaining member on the spindle may comprise feeding a portion of the spindle through the receiving formation comprising an aperture defined by the retaining member so that the retaining member is located between adjacent wheels on the spindle.

The method may further comprise securing the retaining member to the support bracket using a first securing formation of the retaining member.

The first securing formation may comprise an aperture defined by the retaining member, and securing the retaining member to the support bracket includes aligning the first securing formation with a second securing formation comprising an aperture defined by the support bracket, and inserting a securing element through the aligned apertures so as substantially to prevent relative radial movement therebetween.

Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, wherein;

Figure 1 is a perspective view of a conveyor assembly according to embodiments of the invention;

Figure 2 is a perspective view of a portion of a conveyor assembly according to embodiments of the invention;

Figure 3 is a side view of a portion of a conveyor including conveyor assemblies according to embodiments of the invention;

Figure 4 is a perspective view of a support bracket;

Figure 5 is a perspective view of a support bracket shown in cooperation with a retaining member; and

Figure 6 is a side view of a securing element in connection with a retaining member.

Referring now to Figures 1 and 2 a conveyor assembly 10 is shown, that includes an axle formation 12 and a support structure that comprises an axle support 24 and a pair of side mounts 28. The axle formation 12 comprises an elongate spindle 14 supporting a plurality of wheels 18. The wheels 18 are located on the spindle 14 by feeding the spindle 14 through central apertures defined by the wheels 18, through the central axes of the wheels 18. The wheels 18 are of a type known as ‘skate wheels’, which are typically used in conveyors. It should be understood that other types of wheels could be used, and where used in this specification, the term ‘wheels’ is intended to encompass any wheel, roller, or the like, that is suitable for rotation about an axle. The wheels 18 may be formed of any suitable metal, such as steel, or may be formed of a reinforced plastics material. The axle formation 12 also includes a plurality of spacer elements 15 each comprising a cylindrical sleeve configured to encircle a portion of the spindle 14. Each spacer element 15 has a diameter equal to or greater than the diameter of a central aperture defined by a wheel 18, so that adjacent pairs of wheels 18 are separated from one another by at least the length of a respective spacer element 15 disposed between them.

The side mounts 28 are disposed on opposite sides of the conveyor. Each side mount 28 provides a mounting formation 32 for supporting an end portion of the spindle 14. The mounting formation 32 may be a U-shaped slot, as shown in Figure 1. A further securing part such as a nut 16 may be attached to the end of the spindle 12, and may engage the side mount 28, so as to hold the spindle 12 within the mounting formation 32 whilst enabling the spindle 12 to rotate about its axis. A washer 33 may be disposed between the nut 16 and the mounting formation 32 to aid smooth rotation of the spindle 12 and nut 16 and reduce the likelihood of accidental disengagement of the end of the spindle from the mounting formation 32. A spacer element 15 may be disposed between each outermost wheel of the axle formation 12 and its respective side mount 28.

An axle support 24 is disposed, in use, beneath the axle formation 12. The axle support 24 comprises a spanning member 26 that, in use, is disposed across substantially the width of the conveyor between the side mounts 28.

The axle support 24 also comprises one or more support brackets 36 which extend from the spanning member 26. In use, the spanning member 26 is disposed below the axle formation 12, and the support brackets 36 extend generally upwards from the spanning member 26, towards the spindle 14. The support brackets 36 each provide a support formation 40 for supporting a portion of the spindle 14 between adjacent pairs of wheels 18. Such support may be provided via contact with a spacer element 15 disposed on the spindle 14, for example, or may be via direct contact with the spindle 14 itself. Each support formation 40 is configured such that the entire axle formation 12 (i.e. having already been formed, the wheels 18 having been located on the spindle 14) is moveable in a direction substantially perpendicular to the axis defined by the spindle into engagement with the axle support 24. In other words, the axle formation 12, complete with wheels 18, may be moved into engagement with the support brackets 36 without the spindle 14 being moved axially, to ‘feed’ the spindle through a series of apertures as is typically the case with prior art conveyors.

The support formation 40 defines a U-shaped slot in the upper end of the support bracket 36 into which the spindle 14 can be lowered, so that the spindle 14 is free to rotate while resting in the slot. As shown in Figure 1, by providing a plurality of support brackets 36 spaced across the width of the conveyor, the axle formation 12 can be supported at intervals along its length.

Each end of the axle formation 12 is supported by a mounting formation 32 of a respective side mount 28, and a portion of the spindle 12 is supported by each support formation 40 of the support bracket 36.

The conveyor assembly 10 includes at least one retaining member 42. Each retaining member 42 is connected to the axle formation 12 and secured to the axle support 24 to prevent the spindle becoming dislodged from the axle support 24 during use. Each retaining member 42 comprises a generally flat body defining an aperture providing a receiving formation 44 for receiving a portion of a spacer element 15 and a portion of the spindle 12 encircled by the spacer element 15, so that the retaining member 42 is rotatable about the axis of the spindle 12. It should be understood that the spindle 12 may be fed through the receiving portion of the retaining member 42 without passing through a spacer element 15 (in an embodiment in which spacer elements 15 are not included, for example). When forming the axle formation 12 the spindle 14 may be fed alternately through an aperture of a wheel 18 and then through a spacer element 15, which in turn is fed through a receiving formation 44 of a retaining member 42 so that the retaining members 42 are located between pairs of wheels 18, and surrounding spacer elements 15 supported on the spindle 12. A single retaining member 42 may be engaged with an axle formation 12. Alternatively, two or more retaining members 42 may be engaged with the axle formation 12.

When the axle formation 12 is engaged with the axle support 24 each retaining member 42 can be rotated about its point of connection with the spindle 12, and moved lengthwise of the spindle 12, to a position in which it lies alongside a respective support bracket 36. The retaining member 42 has a first securing formation 46 which enables the retaining member 42 to be secured relative to the support bracket 36. In doing so, the portion of the spindle 14 engaged by the receiving formation 44 is secured to the support bracket 36 so as substantially to prevent movement of the spindle 14 radially relative to its axis. In this way, the spindle 12 is prevented from disengaging the support formation 40 of the support bracket 36.

The support bracket 36 includes a second securing formation 38 which cooperates with the first securing formation 46 of a respective retaining member 42. The first and second securing formations 46, 38 may be apertures defined by the retaining member 42 and support bracket 36 respectively. The apertures may be aligned to allow insertion of a securing element 48 through the apertures of the first and second securing formations 38, 46. The securing element 48 may be a pin, a bolt, a rivet, or the like. In embodiments, as shown in Figure 6, the securing element 48 is a rivet such as a plastic rivet of a standard type, which is inserted through the apertures and then deformed by snap-fitting (i.e. pressing the head of the rivet into the shaft of the rivet so as to deform the end of the shaft). This deformation prevents the rivet from being retracted from the apertures, and therefore secures the retaining member 42 (and thereby the axle formation 12) in place relative to the axle support 24. In embodiments the securing element 48 is releasably securable, so that the first securing formation 46 is releasably securable to the second securing formation 38 (for example, using a nut and bolt, or a clipping mechanism). In this manner the axle formation 12 may releasably engage the axle support 24.

As shown in Figure 2, each side mount 28 includes a holding formation 34 configured to receive an end portion of a spanning member 26. The holding formation 34 comprises a substantially U-shaped channel configured to support the underside of the end portion of the spanning member 26. The U-shaped channel preferably fits tightly around the sides and lower edge of the end of the spanning member 26 so that when the end of the spanning member 26 is positioned within the holding formation 34 it movement downwards or laterally perpendicular to its axis is substantially prevented. To fit the spanning member 26 between two opposing side mounts 28 (as shown in Figure 1), it is moved downwards so that its ends each engage a respective holding formation 34. Once each end is engaged with a holding formation 34, the movement of the spanning member 26 downwards, axially, or laterally perpendicular to its axis is substantially prevented.

An extensible conveyor including a plurality of conveyor assemblies 10 according to the invention is shown in Figure 3. It should be understood that the conveyor assembly 10 of the present invention is suitable for use with both extensible and non-extensible conveyors. In embodiments in which the conveyor is not extensible, a surface sheet may overlie the spindle 14 and spanning member 26 so as to cover those parts. The surface sheet may be formed of pressed steel, for example, and the upper parts of the wheels 18 may extend through holes punched in the surface sheet, so as to provide a conveying surface above the sheet.

The conveyor of Figure 3 has a pair of opposed extendible sides, one of which is shown. The conveyor assemblies 10 are supported between the opposed extendible sides, so that a package supported on the wheels 18 of the axle formations 12 can be conveyed along the conveying surface defined by the wheels 18. The sides of the conveyor are supported at each end and at one or more intervals by support legs. In this example, the support legs each comprise a pair of uprights connected by a cross-bar and provided with wheels 16 to enable the conveyor to be moved to a desired position. Flandles are provided at an upper part of the uprights to provide a part of the conveyor which may be safely grasped to enable the conveyor to be moved, extended and contracted as appropriate.

As shown in Figure 3, the sides comprise a plurality of pairs of arms pivotally connected at their mutual midpoint. At either end, each pair of arms is connected to side mounts 28, so that each adjacent pair of side mounts 28 is interconnected by a pair of arms. At a lower part of the side mounts 28, a slideable connection to engage an end of an arm is provided. In this example, the side mounts 28 comprise an elongate slot (not shown in Figures 1 and 2). The adjacent pairs of arms are pivotally connected to the side mounts 28 through a pivot at an upper part thereof about a bolt, pin, or the like engaged with aperture 30 in the side mount 28. Adjacent pairs of arms are also pivotally connected to one another by a pivot at the lower end of the side mounts 28 which is in sliding engagement with the slot. A conveyor assembly 10 is constructed by engaging an axle formation 12 with an axle support 24 and a pair of side mounts 28 as described above. The axle formation 12 is constructed by locating a plurality of wheels 18 and (optionally) spacer elements on the elongate spindle 14, and locating one or more retaining members 42 on the spindle between adjacent pairs of wheels 18.

The support structure is formed by connecting a pair of side mounts 28 to respective sides of a conveyor. The axle support 24 is then fitted to the side mounts 28 by moving it from an unsupported position in which it is not supported relative to the side mounts 28, to a supported position. To achieve this the spanning member 26 of the axle support is fitted relative to the side mounts 28 by engaging the end portions of the spanning member 26 with the holding formations 34 of the side mounts 28, so that the spanning member 26 lies across the width of the conveyor, and such that the spanning member 26 is supported by the side mounts 28. Subsequent to the axle formation 12 being moved to its supported position, the axle formation 12 is then moved into engagement with the support brackets 36. As the axle formation 12 is moved into engagement with the axle support 24, a respective portion of the spindle 14 is supported by the support formation 40 of each support bracket 36 extending from the spanning member 26. At the same time, the axle formation 12 is moved relative to the side mounts 28 from an un-mounted position in which it is not supported by the side mounts 28, into a mounted position in which each end of the spindle 14 is supported by a mounting formation 32 of a respective side mount 28. Using this method the entire axle formation 12 is put together, the support structure is assembled such that the axle support 24 is supported by the side mounts 28, following which the axle formation 12 is moved to its mounted position relative to the side mounts 28 such that the axle formation 12 is also engaged with the axle support 24. Moving the axle formation 12 to its mounted position requires no form of further assembly or disassembly of the axle formation 12.

In an alternative method, the axle formation 12 may engage the axle support 24 before the axle support 24 is supported relative to the side mounts 28. Following this, the axle support 24 and axle formation 12 may be moved together to a position in which the axle support 24 is in its supported position and the axle formation 12 is in its mounted position relative to the side mounts 28.

Whichever of the above methods of manufacturing is followed, it is the case that the axle formation 12 may be constructed separately from the assembly of the other components of the conveyor, including the side mounts 28. Then either the axle support 24 is installed first, followed by the axle formation 12, or else the axle support 24 and axle formation 12 are engaged, and installed as a single joined component.

The or each retaining member 42 may be secured to a respective support bracket 36 using the first securing formation 46. The aperture of the first securing formation 46 is aligned with the aperture of the respective second securing formation 38, and a securing element 46, which is a rivet, is inserted through the aligned apertures so as substantially to prevent relative movement therebetween. The rivet may then be deformed to prevent disengagement of the rivet from the apertures. Securing the retaining members 42 to the axle support 24 may occur when the axle formation 12 is engaged with the axle support 24 before being mounted relative to the side mounts 28, or may occur once the axle formation 12 has been mounted relative to the side mounts 28.

In an alternative embodiment, instead of the spanning member 26 being provided separately from and engaging with the holding formations 34 of the side mounts 28, the ends of the spanning member 26 may be welded to the side mounts 28 so as to form a single fixed structure comprising two side mounts 28 joined to one another by a spanning member 26.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A conveyor assembly for an extendable conveyor including: an axle formation comprising an elongate spindle supporting a plurality of wheels; a pair of side mounts for disposal on opposite sides of a conveyor and each having a mounting formation for supporting an end portion of the spindle; and an axle support comprising a spanning member disposed, in use, across substantially the width of the conveyor between the side mounts, and a support bracket extending, in use, substantially upwards from the spanning member, the support bracket having a support formation for supporting a portion of the spindle, wherein each side mount includes a holding formation configured to receive an end portion of the spanning member such that the axle support, in use, is supported by the side mounts.

2. A conveyor assembly according to claim 1, wherein the axle formation is moveable from an un-mounted position in which the axle formation is not supported by the side mounts, to a mounted position in which each end of the axle formation is supported by a mounting formation of a respective side mount.

3. A conveyor assembly according to claim 1 or claim 2, further including a retaining member having a receiving formation for receiving a portion of the spindle and a first securing formation for securing the retaining member to a support bracket.

4. A conveyor assembly according to claim 3, wherein the receiving formation is an aperture defined by the retaining member.

5. A conveyor assembly according to claim 3 or claim 4, wherein the support bracket includes a second securing formation for cooperation with a respective first securing formation of a retaining member.

6. A conveyor assembly according to claim 5, wherein the first securing formation and the second securing formation are both apertures, the conveyor assembly further including a securing element for insertion through the apertures of the first and second securing formations when aligned with one another.

7. A conveyor assembly according to any one of claims 3 to 6, wherein the first securing formation is releasably securable to the support bracket.

8. A conveyor assembly according to any one of the preceding claims, wherein each side mount includes a holding formation configured to receive an end portion of a spanning member.

9. A conveyor assembly according to claim 8 wherein each holding formation comprises a substantially U-shaped channel for supporting an end portion of a spanning member.

10. A conveyor assembly according to claim 8 or claim 9 wherein in use the holding formation substantially prevents lateral movement of the spanning member perpendicular to its axis and relative to the holding formation.

11. A conveyor assembly according to any one of the preceding claims, comprising a plurality of support brackets.

12. An extendable conveyor including a plurality of conveyor assemblies according to any one of the preceding claims.

13. A method of manufacturing a conveyor assembly for an extendable conveyor, comprising the steps of: locating a plurality of wheels on an elongate spindle to form an axle formation; providing a pair of side mounts each having a mounting formation for supporting an end portion of the spindle and each having a holding formation for receiving an end portion of a spanning member; providing an axle support comprising a spanning member and a support bracket, the support having a support formation for supporting a portion of the spindle; and moving the axle support relative to the side mounts from an unsupported position in which the axle support is not supported by the side mounts to a supported position in which each end of the spanning member is received by a holding formation such that the axle support is supported by the side mounts.

14. A method according to claim 13, wherein moving the axle support to the supported position further comprises engaging each end portion of the spanning member with a holding formation of a respective side mount.

15. A method according to claim 14 wherein engaging an end portion of the spanning member with a respective holding formation includes positioning the end portion of the spanning member so that it is supported by a U-shaped channel comprised by the holding formation, such that lateral movement of the spanning member perpendicular to its axis and relative to the holding formation is substantially prevented.

16. A method according to any one of claims 13 to 15, wherein locating the plurality of wheels on the elongate spindle to form an axle formation further comprises feeding the spindle through central apertures defined by the wheels.

17. A method according to claim 16, wherein locating the plurality of wheels on the elongate spindle to form an axle formation further comprises locating one or more spacer elements on the spindle, the or each spacer element comprising a sleeve configured to encircle a portion of the spindle between adjacent wheels.

18. A method according to claim 16 or claim 17, wherein locating the plurality of wheels on the elongate spindle to form an axle formation further comprises locating a retaining member on the spindle, the or each retaining member having a receiving formation for receiving a portion of the spindle and a first securing formation for securing the retaining member to a support bracket.

19. A method according to claim 18, wherein locating the or each retaining member on the spindle comprises feeding a portion of the spindle through the receiving formation comprising an aperture defined by the retaining member so that the retaining member is located between adjacent wheels on the spindle.

20. A method according to claim 18 or claim 19 further comprising securing the retaining member to the support bracket using a first securing formation of the retaining member.

21. A method according to claim 20 wherein the first securing formation comprises an aperture defined by the retaining member, and securing the retaining member to the support bracket includes aligning the first securing formation with a second securing formation comprising an aperture defined by the support bracket, and inserting a securing element through the aligned apertures so as substantially to prevent relative radial movement therebetween.