GB2457156A

GB2457156A - Load Palletising Device

Info

Publication number: GB2457156A
Application number: GB0901769A
Authority: GB
Inventors: Keith Mander
Original assignee: AVANTI CONVEYORS Ltd
Current assignee: AVANTI CONVEYORS Ltd
Priority date: 2008-02-06
Filing date: 2009-02-04
Publication date: 2009-08-12
Anticipated expiration: 2029-02-04
Also published as: GB0901769D0; GB0802127D0; GB2457156B

Abstract

A load palletising device features a flat bed conveyor 22, with grooves 28, supporting a load 18 for palletizing. The grooves 28 may receive a plurality of forks 24 from a mechanism which lifts the load 18 up such that a pallet can be placed below the load 18. The load 18 may also be squared in position on the pallet by squaring plates 4,8. The system may allow the use of a flat bed conveyor, as opposed to current roller based systems, as a more supportive carrier of weaker pallets.

Description

Load Palletising Device The present invention relates to a load palletising device for placing a load of goods on a platform, such as a pallet, board or other platform for onward transportation. The present invention also relates to a method of operation of such a load palletising device.

A load palletising device is a device which places loads onto platforms, such as pallets, boards, load edge support bars or other platforms suitable for facilitating the onward transportation of the goods. The load may be flat packed boxes, trays or corrugated sheets. Alternatively, the load may comprise goods, such as, drums, furniture, bricks, appliances, parts, or other types of goods which require subsequent transportation on a platform, such as a pallet.

Generally load palletising devices comprise two opposing squaring heads, one located to each side of a conveyor system, typically a roller conveyor.

Each squaring head has a set of forks associated with it and a fork driving system for advancing the forks under the load and for lifting the forks, so as to lift the load. A pusher device is also provided for locating a pallet under a lifted load. The squaring heads have a head driving system, which is mechanically or electrically synchronised to centre the load so that it is aligned with the pusher device.

In operation, the fork driving device extends the sets of forks towards each other into an extended state in which they move into spaces provided in the conveyor. The forks are located at a level below an effective upper transportation surface of the conveyor. Then the conveyor system transports a load into the space between the opposing squaring heads, for example, a load of stacked corrugated sheets. The squaring heads then move towards the load, and abut opposite sides of the load so as to centre the load and simultaneously the forks move further underneath the load into a fully extended position. Once the opposing squaring heads abut opposing sides of the load, with the forks located underneath the load, the forks are lifted by the fork driving device so as to lift the load. When the forks are at a height above the conveyor greater than the height of a pallet, the pusher device locates a pallet directly below the load. The fork driving device then lowers the forks to the level of the top of the pallet and withdraws the forks, with the squaring heads still abutting the load, to smoothly place the load on top of the pallet.

Once the forks are withdrawn from the load, the squaring heads move away from the load, back to their starting position and the fork driving device extends the forks ready for the next load. The palletised load, is then moved out of the load palletising device by the conveyor.

A roller conveyor is made up of an array of spaced cylindrical rollers and so in order to enable the forks to move beneath the load, the rollers must be spaced apart in the region of the paUetising device in order to provide spaces for the forks to advance into. This generates problems for narrow slatted pallets, lightweight pallets and one direction pallets. One direction pallets can only be used, where the runners on the underside of the pallet are in the same direction as the conveying direction so that they can bridge the spaces between the rollers. Typically, spaces between adjacent rollers of at least 75mm must be provided for the forks. This means that the pallets must be sufficiently strong so that they do not bend or break as they pass over the spaces. There is an increasing trend to save costs by reducing the amount of wood in wooden pallets and by making the slats used to make the pallets thinner or narrower. This is causing increasing problems with pallets breaking or becoming jammed or snagged.

In order to overcome this problem, some load palletising devices use a conveyor having more closely spaced rollers, with moveable bars located between adjacent rollers. The bars rise up to raise the load sufficiently above the roller conveyor so that forks can be extended underneath the load to support the load. The bars are then lowered and a pallet is moved onto the conveyor underneath the load. The forks and squaring heads are then withdrawn from the load. These machines have the disadvantage of a slower cycle time because of the additional steps of raising and then lowering the bars. Also, these machines have additional machinery underneath the conveyor, which can be disrupted by pieces of wood and corrugated board that fall onto the conveyor. Also, such known palletising devices cannot accommodate different pallet heights.

Load palletising devices generally work automatically with the conveyor, head and fork assembly working together using an automated system which may be operated manually or under the control of software.

Load conveyors are becoming more popular which have a flat bed, such as those which are belt or chain driven. For example, the flat bed conveyor may be made of a mesh of hinged plastic tiles or of wood or metal, for example, steel, slats. Flat bed conveyors, provide a flat surface on which to transport loads, pallets and palletised loads, so reducing the likelihood of damage to the loads and/or pallets. However, such flat bed conveyors are currently not compatible with load palletising devices.

According to the present invention there is provided a load palletising device comprising: a flat bed conveyor having a load carrying surface; a fork assembly moveable towards and away from the conveyor, each fork assembly comprising a plurality of forks extending in a first direction towards the conveyor; wherein at least part of the load carrying surface of the conveyor is formed with a series of equally spaced laterally extending grooves, dimensioned to at least partially receive the forks of the fork assembly or assemblies. The operation of the device may comprise the steps of: conveying a load to a position adjacent the fork assembly or assemblies on a grooved portion of the conveyor; aligning the groves of the grooved portion of the conveyor with the forks of the fork assembly or assemblies; moving the or each fork assembly in a direction towards the load so that the forks slide into the grooves in the grooved portion of the conveyor; lifting the or each fork assembly so as to lift the load; locating a platform underneath the load on the conveyor, optionally on a flat portion of the conveyor; and withdrawing the or each fork assembly from beneath the load so that the load drops onto the platform. Accordingly, the device facilitates palletising of loads without requiring a platform to be carried on a surface formed with large spaces or grooves for receiving forks and which can damage pallets. Also, the cycle time of the palletising device is not adversely increased.

The device may comprise a pair of the fork assemblies, for example, one to each side of the conveyor. The device may additionally comprise a pair of squaring heads, for example, a pair of opposing squaring heads one to each side of the conveyor and moveable towards and away from each other.

Operation of the device may then comprise the steps of: conveying a load on a grooved portion of the conveyor to a location between the squaring heads and the fork assemblies; moving the fork assemblies towards each other so that the forks slide from both sides of the conveyor into the grooves in the conveyor; moving the squaring heads towards each other so that opposing heads abut opposing sides of the load; lifting the forks so as to lift the load; locating a platform underneath the load; moving the fork assemblies away from each other and so withdrawing from beneath the load so that the load drops onto the platform; and moving the squaring heads away from each other.

The or each fork assembly may comprise a drive bar having a longitudinal axis and the forks may be fixed to the drive bar, extending substantially radially therefrom in said first direction. Each fork assembly, may comprise at least ten forks and preferably around fourteen forks. Conventionally, around seven forks are used in each fork assembly and so the use of more forks means that each fork can be narrower (in the direction of travel of the conveyor) meaning that the grooves in the conveyor may be narrower in this direction. Using narrower grooves reduces the risk of platforms, such as pallets, being damaged. The grooves may be deep enough to receive the entire forks, or may have a depth which accommodates only a lower portion of the forks.

Each fork may taper in the first direction to a thin substantially horizontal edge at a first end of the fork. In this case, each groove may have a depth for receiving only a lower portion of each fork.

The forks may be pivotable between a first position in which a lower surface of each fork is substantially horizontal and a second position in which an upper surface of each fork is substantially horizontal. In particular, the forks in the or each fork assembly may be pivotable about a common substantially horizontal axis located at the ends of the forks remote from the first ends. Where the forks are pivotable, the or each fork assembly may comprise a drive bar having a longitudinal axis, which drive bar may be pivotable about said axis and the forks may be fixed to the drive bar, extending substantially radially therefrom in said first direction.

A portion of the carrying surface of the conveyor may be flat, for conveying a platform into the palletising device, and a portion of the carrying surface may grooved for conveying a load into the palletising device. In this case, the conveyor may be a loop conveyor and the flat and grooved portions may be opposite each other on the loop. Where such a loop conveyor is used operation of the device may comprise the steps of: conveying a load to a position adjacent the fork assembly or assemblies with a grooved portion of the conveyor uppermost; aligning the groves of the grooved portion of the conveyor with the forks of the fork assembly or assemblies; moving the or each fork assembly in a direction towards the load so that the forks slide into the grooves in the grooved portion of the conveyor; lifting the or each fork assembly so as to lift the load; moving a flat portion of the conveyor uppermost and locating a platform underneath the load on a flat portion of the conveyor; and withdrawing the or each fork assembly from beneath the load so that the load drops onto the platform.

There is also, provided a load palletising device comprising: a conveyor; and a fork assembly moveable towards and away from the conveyor, each fork assembly comprising a plurality of forks extending in a first direction towards the conveyor, in which each fork tapers in the first direction to a thin substantially horizontal edge at a first end of the fork; wherein the fork first ends when moved towards each other are slideable between an upper surface of the conveyor and a base of a load resting on the upper surface of the conveyor. This facilitates the use of a flat bed conveyor, having a substantially flat upper surface, or a roller conveyor without spaces, in a load palletising device and so avoids the problems of platforms, such as pallets becoming damaged. Also, this solution does not affect the speed of a complete cycle of the load palletising device.

In this case, operation of the load palletising may comprise the steps of: conveying a load on the conveyor to a position adjacent the fork assembly or assemblies; moving the or each fork assembly in a direction towards the load so that the forks slide between the load and the conveyor; lifting the or each fork assembly so as to lift the load; locating a platform underneath the load; and withdrawing the or each fork assembly from beneath the load so that the load drops onto the platform.

The load palletising device may comprise a pair of the fork assemblies, one to each side of the conveyor. Where a pair of fork assemblies are used, they may be level with each other at the level of the surface of the conveyor and the first ends of the forks may extend substantially half way across the conveyor when fully extended. The device may also include a pair of opposing squaring heads, one each side of the conveyor and moveable towards and away from each other. The squaring heads steady and align the load as it is transferred from the conveyor to a platform, such as a pallet. In this case operation of the load palletising device may comprise the steps of: conveying a load on the conveyor to a position between the squaring heads and the fork assemblies; moving towards the fork assemblies towards each other so that the forks slide from both sides of the conveyor between the load and the conveyor; moving the squaring heads towards each other so that opposing heads abut opposing sides of the load; lifting the forks so as to lift the load; locating a platform underneath the load; moving the fork assemblies away from each other and so withdrawing from beneath the load so that the load drops onto the platform; and moving the squaring heads away from each other.

The forks may be pivotable, as described above, between a first position in which a lower surface of each fork is substantially horizontal, for facilitating sliding of the forks over the substantially flat surface of the conveyor, between the conveyor and the load, and a second position in which an upper surface of each fork is substantially horizontal, for facilitating lift of the load on a substantially horizontal surface.

Where the forks are pivotable, the method of operation of the load palletising device may comprise the additional steps of: when the forks are beneath the load, pivoting the forks from a position in which a lower surface of each fork is horizontal to a position in which the upper surface of each fork is horizontal.

The invention will now be described by way of example only and with reference to the accompanying schematic drawings, wherein: Figure 1 shows a partial transverse cross-section of a load palletising device suitable for use with the present invention in an initial position with a load introduced; Figure 2 shows a partial transverse cross-section of the load palletising device of Figure 1 with squaring heads and fork assemblies fully advanced and the load resting on the fork assemblies; Figure 3 shows a partial transverse cross-section of the load palletising device of Figure 2 with the fork assemblies upwardly pivoted and lifted to above pallet height and with a pallet inserted below the load; Figure 4 shows a partial transverse cross-section of the load palletising device of Figure 3 with the fork assemblies withdrawing from under the load and pivoted downwardly; Figure 5 shows a partial transverse cross-section of the load palletising device of Figure 4 with the squaring heads and fork assemblies fully withdrawn and with the load resting on the pallet; Figure 6 shows a plan view of the load palletising device of Figure 1; Figure 7 shows a plan view of a load palletiser device according to the present invention in an initial position with the load introduced; Figure 8 shows a partial cross section through lines AA of Figure 7; and Figures 9A to 91 show longitudinal cross-sections through the type of load palletiser shown in Figure 7 using a different conveyor.

Figures 1 and 6 show a load palletising device which comprises a flat bed conveyor (2), which may be chain or belt driven. The flat bed conveyor (2) passes between an opposing pair of squaring heads (4) and opposing fork assemblies (6). Each squaring head (4) comprises an oblong plate having a front surface (8) aligned parallel to the direction of travel (10) of the conveyor (2). Each squaring head (4) is driven in the direction of arrow B, either via a hydraulic drive system or an electrical drive system, for example using servo-motors. This drive system is controlled by an automated drive system of the palletising device. Each fork assembly (6) comprises a pivotable drive bar (12) and an array of fifteen forks (14). Each fork assembly (6) is driven in the direction of arrow B, again either via a hydraulic drive system or an electrical drive system, for example using servo-motors. This drive system may be separate from or integrated with the drive system for the squaring heads (4) and is controlled by the automated drive system of the palletising device. The forks (14) are either formed integrally with the pivotable drive bar (12) or are fixed to the pivotable drive bar. The pivotable drive bar (12) is driven by the fork assembly drive system to pivot about its axis so that the forks (14) move in the direction of arrow C. Each fork (14) tapers from the pivotable drive bar (12) to a knife edge (16).

The operation of the load palletising device will now be described with reference to Figures 1 to 5.

As shown in Figure 1, in an initial position of the palletising device, the squaring heads (4) and the fork assemblies (6) are withdrawn, with the bottom surface of each fork (14) horizontal and level with an upper surface of the conveyor (2). Then a load (18) is conveyed into the palletising device, between the squaring heads on the flat bed conveyor (2).

Then the automatic drive system pushed the fork assembly (6) and the squaring heads (4) towards the load until the forks (14) are pushed between the load (18) and an upper surface of the conveyor (2). The squaring heads move towards the load until the facing front faces (8) of the squaring heads abut associated sides of the load (18). Where the load is a stack of corrugated sheets or flat packed boxes, then the squaring heads align the sheets and centre the load (18), as shown in Figure 2. The knife edges (16) of the forks (14) slide between the base of the load (18) and the upper surface of the conveyor and as the forks move towards each other under the load, the load is lifted and slides over the sloping upper surfaces of the forks (14) so that the load is supported on the forks, as shown in Figure 2.

The automatic drive system of the palletising device then pivots the drive bars (12) so that the knife edges (16) of the forks (14) move upwardly until the upper surfaces of the forks are horizontal, to better support the load (18). The automatic drive system then lifts the fork assemblies (6) into the position shown in Figure 3, so as to create a space between the underneath of the forks (14) and the upper surface of the conveyer large enough to receive a pallet (10). Then a pallet (10) is then conveyed into the space between the forks (14) and the conveyor (2), as is shown in Figure 3.

With the load (18) still centred between the squaring heads (4), the fork assemblies (6) are withdrawn and as they are withdrawn the pivotable bar (12) is pivoted so that the knife edges (16) move back down until the bottom surface of the forks (14) are horizontal, as shown in Figure 4. As the forks (14) are withdrawn from beneath the load (18), the load drops onto the pallet (10) still supported on two sides by the abutting squaring heads (4). The squaring heads (4) are then withdrawn and the fork assemblies (6) are further withdrawn to the initial position. The load (18) now rests squarely on the pallet (10), as shown in Figure 5 and is then conveyed, by the conveyor (2) out of the palletising device.

As the flat bed conveyor (2) has a substantially flat surface, weaker pat lets (10) can be used without causing pallet breakage, when compared to roller conveyors.

A the load palletiser device according to the present invention similar to that described above, is shown in Figures 7 and 8, with like parts identified by like numerals. The differences are that the conveyor (22) is slotted and the forks (24) are not tapered.

In the device of Figures 7 and 8, the conveyor (22) is of flat bed conveyor construction, but is formed with regularly spaced transverse grooves (28) along, at least part of its upper surface. The grooves (28) are dimensioned so that they are able to receive a fork (24) of a fork assembly (26) of the load palletising device of Figure 7. The grooves (28) have the same spacing between them as the spacing between the forks (24) of the fork assemblies (26). The fork assembly (26) comprises a driving bar (12) and fifteen forks (24). In this embodiment, the forks (24) do not taper to a knife edge.

As shown in Figures 7 and 8, in an initial position of the palletising device, the squaring heads (4) and the fork assemblies (26) are withdrawn, with the bottom surface of each fork (14) horizontal and level with the base of the grooves (28) of the conveyor (2). Then a load (18) is conveyed into the palletising device, between the squaring heads on the conveyor (2). The conveyor (22)is halted with the load between the squaring heads (4) and with the grooves (28) of the conveyor aligned with the forks (24) of the fork assemblies (26) of the palletising device.

Then the automatic drive system pushes the fork assemblies (6) and the squaring heads (4) towards the load until the forks (24) are pushed into the grooves (28) of the conveyor (22), beneath the load. The squaring heads move towards the load until the facing front faces (8) of the squaring heads abut associated sides of the load (18). The automatic drive system then lifts the fork assemblies (26), so as to create a space between the underneath of the forks (24) and the upper surface of the conveyer (22) large enough to receive a pallet (10). Then a pallet is conveyed into the space between the forks (24) and the conveyor (22).

With the load (18) still centred between the squaring heads (4), the fork assemblies (26) are withdrawn from beneath the load (18) and the load drops onto the pallet still supported on two sides by the abutting squaring heads (4).

The squaring heads (4) are then withdrawn and the fork assemblies (26) are further withdrawn to the initial position of Figures 7 and 8. The load (18) now rests squarely on the pallet and is then conveyed, by the conveyor (22) out of the palletising device.

The fork assembly (26) of Figures 7 and 8 uses fifteen forks, as opposed to the usual seven or so forks used on know palletiser devices. As a result of this the forks can be narrow (in the direction of travel of the conveyor) and still support a heavy load (18). This means that the grooves (28) of the conveyor (22) are relatively narrow, as compared to spaces for forks in known roller conveyors. Thus weaker pallets (10) can still be used with a reduced risk of causing pallet breakage, when compared to roller conveyors. However, ideally the palletiser device should have a substantially flat surface for supporting a pallet.

The embodiments of Figures 7 and 8 can be further improved, by adopting a conveyor (32) that has a grooved portion for supporting the load (18) and a substantially flat, ungrooved portion for supporting the pallet (10). This may be done in several ways, for example by having a reciprocating conveyor, which can locate the grooved portion of the conveyor in the palletising device to transport the load into the device and then when the load is lifted from the conveyor, locates the ungrooved portion of the conveyor in the palletising device to transport the pallet underneath the load and to then transport the palletised load onwardly.

Alternatively, the conveyor (22) may be replaced by the closed loop mixed surface conveyor (32) of the type shown in Figures 9A to 91 in which part of the conveyor surface is substantially flat and part of the conveyor is grooved, as the conveyor (22) of Figures 7 and 8 is grooved. Other than the change of the conveyor (22) to the mixed surface conveyor (32) and the reduction of the number of forks (24) and hence an associated alteration to the groove (28) width and spacing, the load palletising device of Figures 9A to 91 is the same as that shown in Figures 7 and 8.

Figure 9A shows the mixed surface conveyor (32), which comprises a chain or belt driven loop conveyor which passes around at least two rotary driving hubs (34). The conveyor (32) is of flat bed construction, comprising hinged plastic tiles or slatted wood or metal as is known in the art. Substantially, half of the outer surface of the loop conveyor (32) (shown as a top surface in Figure 9A) has a substantially flat surface (36) with the remainder of the outer surface (shown as a bottom surface in Figure 9A) has a grooved surface (38), formed with spaced grooves (28) as shown and described above in relation to Figures 7 and 8.

The mixed surface conveyor (32), is driven by the hubs (34) which are driven by the automated drive system of the palletising device. The conveyor (32) is coordinated with an adjacent conveyor (not shown), which adjacent conveyor conveys the load (18) onto the grooved surface (38) of the mixed surface conveyor (32) as is shown in Figure 98. That is, the grooved surface (38) moves to be the top surface and the flat surface (36) moves to be the bottom surface. The load palletising device is in its initial position in Figure 9B, with the squaring heads (4) withdrawn and with the grooves (28) of the conveyor (32) aligned with the withdrawn forks (24) as shown in Figures 7 and 8.

With the conveyor (32) remaining in the aligned position of Figure 9B, the forks (24) of the fork assemblies (26) are then driven into the grooves (28) underneath the load (18), as is shown in Figure 9C. In Figure 9C, the squaring heads (4) have advanced to abut opposing sides of the load (18).

Then with the forks (24) fully extended beneath the load (18) to forks lift the load above the grooved surface (38) of the conveyor (32), with the load supported on opposing side surfaces by the squaring heads (2), as is shown in Figure 9D. The conveyor (32) is then driven to move the substantially flat surface (36) uppermost, as is shown in Figure 9E. With the flat surface (36) uppermost, a pallet (10) is located on the flat surface, as is shown in Figure 9F.

The forks (24) are then lowered to the upper surface of the pallet (10) and the load (18) lowers on the forks, between the abutting squaring heads (4), as is shown in Figure 9G. Then the forks (24) are withdrawn and the load (18) comes to rest on the upper surface of the pallet, between abutting squaring heads (4) and the squaring heads are then withdrawn, as shown in Figure 9H.

In this way, the load (18) is placed centrally and neatly stacked upon the pallet (10), with the pallet (10) resting on the substantially flat surface (36) of the conveyor (32). The pallet (10) is then conveyed on the flat surface (36) of the conveyor (32) to an adjacent conveyor for onward transportation and the conveyor returns to the Figure 9A position, ready for the next load.

Instead of the forks (24), the device of Figures 7, 8 and 9A to 91 could have tapered forks (4) of the type shown in Figures 1 to 6, and in this case, the grooves (28) need not be the full depth of the forks at their roots (adjacent the driving bar (12)). In this arrangement, the knife edge ends (16) of the forks would move into the grooves (28) underneath the load (18). Then as the forks (4) advance further into the grooves, the upper surface of the thicker root portion of the forks would engage the base of the load (18) and begin to lift the load from the conveyor (22).

Claims

CLAIMS1. A load palletising device comprising: a flat bed conveyor having a load carrying surface; a fork assembly moveable towards and away from the conveyor, each fork assembly comprising a plurality of forks extending in a first direction towards the conveyor; wherein at least part of the load carrying surface of the conveyor is formed with a series of equally spaced laterally extending grooves, dimensioned to at least partially receive the forks of the fork assembly or assemblies.
2. A device according to claim 1 comprising a pair of the fork assemblies, one to each side of the conveyor.
3. A device according to claim 1 or claim 2 additionally comprising: a pair of opposing squaring heads one each side of the conveyor and moveable towards and away from each other.
4. A device according to any one of the preceding claims wherein the or each fork assembly comprises a drive bar having a longitudinal axis and the forks are fixed to the drive bar, extending substantially radially therefrom in said first direction.
5. A device according to any one of the preceding claims in which each fork tapers in the first direction to a thin substantially horizontal edge at a first end of the fork.
6. A device according to claim 5 wherein the forks are pivotable between a first position in which a lower surface of the fork is substantially horizontal and a second position in which an upper surface of the fork is substantially horizontal.
7. A device according to claim 6 wherein the forks in the or each fork assembly are pivotable about a common substantially horizontal axis located at the ends of the forks remote from the first end.
8. A device according to any one of the preceding claims wherein the or each fork assembly comprises at least ten forks.
9. A device according to any one of the preceding claims wherein a portion of the carrying surface of the conveyor is flat and a portion of the carrying surface is grooved.
10. A device according to claim 9 wherein the conveyor is a loop conveyor and the flat and grooved portions are opposite each other on the loop.
11. A method of operating the device according to any one of claims 1 to 10, comprising the steps of: conveying a load to a position adjacent the fork assembly or assemblies on a grooved portion of the conveyor; aligning the groves of the grooved portion of the conveyor with the forks of the fork assembly or assemblies; moving the or each fork assembly in a direction towards the load so that the forks slide into the grooves in the grooved portion of the conveyor; lifting the or each fork assembly so as to lift the load; locating a platform underneath the load on the conveyor; and withdrawing the or each fork assembly from beneath the load so that the load drops onto the platform.
12. A method according to claim 11 wherein the step of locating a platform comprises, locating a platform underneath the load on a flat portion of the conveyor.
13. A method according to claim 11 or claim 12 when dependent on claim 2 and claim 3 comprising the steps of: conveying a load on a grooved portion of the conveyor to a location between the squaring heads and the fork assemblies; moving the fork assemblies towards each other so that the forks slide from both sides of the conveyor into the grooves in the conveyor; moving the squaring heads towards each other so that opposing heads abut opposing sides of the load; lifting the forks so as to lift the load; locating a platform underneath the load; moving the fork assemblies away from each other and so withdrawing from beneath the load so that the load drops onto the platform; and moving the squaring heads away from each other.
14. A method of operation according to claim 11 or claim 12, when dependent on claim 10, comprising the steps of: conveying a load to a position adjacent the fork assembly or assemblies with a grooved portion of the conveyor uppermost; aligning the groves of the grooved portion of the conveyor with the forks of the fork assembly or assemblies; moving the or each fork assembly in a direction towards the load so that the forks slide into the grooves in the grooved portion of the conveyor; lifting the or each fork assembly so as to lift the load; moving a flat portion of the conveyor uppermost; locating a platform underneath the load on a flat portion of the conveyor; and withdrawing the or each fork assembly from beneath the load so that the load drops onto the platform.