[0001] The present invention relates to a palletising system for use in the transport and
handling of articles or groups of articles.
BACKGROUND TO THE INVENTION:
[0002] Many loads of articles or groups of articles are handled upon pallets using a forklift
truck. Whilst such an arrangement may simplify handling of the load at the manufacturer's
premises and in subsequent transport to the end user and storage at the end user's
premises, such pallets often represent a nuisance to the end user.
[0003] Firstly, the end user must unload the load and its associated pallet from the road
trailer or other transport means by which the load is supplied to the end user. Having
unloaded the palletised load, the end user must then unpack the load from the pallet.
Often, the end user has a large number of such palletised loads in his premises and
each load results in an empty pallet which must be removed from the storage area so
as not to act as an obstacle to free passage of workmen and machines in the storage
area.
[0004] Secondly, having unloaded the pallet and having provided storage for the empty pallet,
the end user must then return the empty pallet to the manufacturer or face a charge
for the loss of that pallet. As a result, the pallet is handled many times for each
delivery of a load to the end user and return to the supplier. This causes wear and
tear to the pallet as well as adding cost for the end user.
[0005] Despite these disadvantages in the use of pallets, they are the commonly accepted
and used method for handling loads.
SUMMARY OF THE INVENTION:
[0006] According to one aspect of the present invention there is provided a palletising
system as specified in claim 1.
[0007] By providing open topped channels in the load bearing pallet, an end user can unload
only the load and not the associated pallet from the flat bed of the road truck or
other transport means bringing the load onto his premises. The end user thus does
not remove the pallet from the truck, so that the pallet can be returned directly
to the supplier without having to be handled on the end user's premises. Alternatively,
the end user can unload both the pallet and its associated load for storage on site
by engaging the tines of the fork lift truck with those channels having a closed top.
When the user requires to unpack the load, it can readily be lifted off the pallet
and unpacked separately. The unloaded pallet can then be handled by a fork lift truck
by inserting the tines of the fork lift truck into the passages which have closed
tops. The invention thus enables an end user to avoid the need to handle and store
empty pallets on site and minimises handling of such pallets as may remain on site.
[0008] It is preferred that the close top channels have open bottoms. This permits access
of fork lift tines from below as well as from one side, and reduces the weight of
the pallet.
[0009] The pallet of the invention comprises a generally planar load bearing surface which
is adapted to receive the load to be carried by the pallet. The surface is preferably
substantially flat and will typically have a square or rectangular plan shape to mimic
the load bearing top surface of a conventional pallet. The surface may be a continuous
surface, except for the locations at which the open topped channels are positioned.
[0010] In a particularly preferred form of the pallet of the invention, the load bearing
surface is provided by a sheet of material which is corrugated to form a series of
parallel open topped channels with intermediate channels which have an open base but
a closed top. Preferably, such corrugations have a squared or tapered cross section
to aid accurate location of the tine of the fork lift truck in the corrugations and
to minimise excessive lateral movement of the tine within the channel. The cross sectional
size and shape of the corrugations and the location of the corrugations across the
plan area of the load bearing surface can be selected according to the type of load
to be carried and the spacing between the tines of the fork lift truck. Thus, for
example the load bearing surface may have a plurality of parallel corrugations at
10 to 15 cm spacing.
[0011] The load bearing surface may be provided with underlying support or bracing structures,
for example transverse blocks or vertical webs between the side walls of adjacent
open topped channels to enhance the strength and rigidity of the pallet. However,
we have found that a satisfactory pallet can be made from a simple corrugated sheet
metal or plastic, notably one incorporating glass fibre or metal rod or other re-inforcement,
since the tines of the fork lift truck or other lifting mechanism extend through the
structure of the pallet and provide a measure of rigidity and support to the pallet.
The exact form and thickness of the sheet from which such a pallet is made will depend
upon the load which the pallet is to carry. Typically, such a load will be at least
100 kg, usually 500 to 2000 kg, and the sheet can readily be selected from commercially
available materials as is known in the industry having regard to the safety and other
requirements for pallets to carry such a load.
[0012] The term load bearing is therefore used herein in respect of the pallet of the invention
to denote that it can support a load of at least 100 kg, preferably at least 2000
kg.
[0013] For convenience, the invention will be described hereinafter in terms of a preferred
embodiment of the pallet which is a corrugated sheet to provide alternating closed
top and open top channels.
[0014] Such a pallet can be readily made by rolling or otherwise corrugating a sheet metal
of suitable thickness using conventional techniques and equipment. However, it is
preferred to form the pallet from a structural or reinforced plastic material which
is vacuum formed, extruded, injection of otherwise moulded or cast into the desired
corrugated form. This can be done using conventional techniques and equipment. A particularly
preferred material for use in the manufacture of the pallet of the invention is a
plastic or zinc coated corrugated sheet, for example of the type used to provide metal
cladding sheets for buildings; or a moulded polyalkylene polymer sheet, notably a
polyethylene or polypropylene sheet. Recycled plastics materials may be used form
the pallet.
[0015] The invention has been described above in terms of a load bearing surface having
open topped channels. However, it may be desired to provide such channels with hinged
top members which pivot about their longitudinal edges to provide a closed top to
the channel, but pivot upwardly to allow a tine located in the underlying channel
to pivot the top members aside as the tine rises out of the channel. If desired, the
top member may be formed as two opposed half tops, each pivoted to an opposed edge
of the lip of the channel to reduce the height of the flap which is formed as the
top members are pivoted upwardly by the rising tine. Such top members may be desirable
where the pallet is to carry a fluent material contained within a flexible walled
bag as opposed to a rigid container or series of rigid articles in a box or shrunk
wrapped to form a unitary load.
[0016] The invention has also be described above in terms of a pallet into the passages
of which the tines of a fork lift truck are inserted from one direction. The invention
may also be applied to a pallet where the tines can enter passages from all four directions.
This is achieved by forming the pallet with two series of passages at right angles
to one another so that the tines can enter passages either from either front or back
or from either side. Such passages can be formed at different levels in the pallet,
for example by securing two corrugated sheets to each other with the line of the corrugations
in one sheet at right angles to the line of corrugations in the other sheet. It will
be necessary to remove material from either the upper or lower sheet to allow the
passage of tines upwardly through the composite structure to engage the base of a
load carried on the upper sheet, for example by removing material from the upper sheet
at the points where the top lines of corrugations overlie the base of the corrugations
in the bottom lines of corrugations.
[0017] Alternatively, notably where the pallet is formed by moulding a suitable plastic,
both lines of corrugations can be formed in the same sheet of material to give a structure
which comprises a sheet member having a series of upraised dimples extending normally
to either side of the plane of the sheet, the dimples being laid out on a grid pattern
similar to an egg crate design. The dimples can be provided by metal or other blocks
attached at the desired locations on both sides of a metal sheet, but are preferably
formed by a suitable vacuum or other moulding technique in a sheet of plastic material.
This structure allows the interlocking of pallets for stacking.
[0018] The movable tine or tines of the fork lift permit adjustment of the effective number
of tines. For example, two tines can become one, or three tines can become one. This
means that the fork lift truck can pick up pick up pallets of different sizes. In
a preferred embodiment, adjacent tines may be interlocked together to form a single
lifting structure. The tines may be moved laterally by any suitable means, for example
by means of hydraulics. The tines of the fork lift may be provided as an attachment
which is mounted on a suitable vehicle. Accordingly, another aspect of the invention
provides an attachment for the rise and fall mechanism of a fork lift truck or the
front end loader of a tractor as specified in claim 8.
[0019] Although the pallet and the fork lift form the system, these items could also be
manufactured and sold separately, and could be used separately. Accordingly, another
aspect of the invention provides a pallet as specified in claim 10.
DESCRIPTION OF THE DRAWINGS:
[0020] The invention will now be further described by way of illustration, with reference
to the following drawings in which:
Figure 1 is a diagrammatic cross sectional view through one form of a pallet in accordance
one aspect of the invention;
Figure 2 is a plan view of a pallet in accordance with another embodiment of a pallet
in accordance with one aspect of the invention;
Figure 3 is a side elevational view of the pallet shown in Figure 2;
Figure 4 is a perspective view of part of the pallet shown in Figure 2;
Figure 5 is a side elevational view of an attachment for a fork lift in accordance
with another aspect of the invention;
Figure 6 illustrates diagrammatically an alternative attachment for a fork lift truck;
Figure 7 is a diagrammatic illustration of another alternative attachment for a fork
lift truck; and
Figure 8 shows side elevational views of interlocking tines of differing sectional
shapes in accordance with another aspect of the invention.
DETAILED DESCRIPTION:
[0021] The pallet shown in Figure 1 comprises a sheet member 1 which has been formed into
corrugations 2, some of which have an open top 3, and intermediate ones which have
a closed top but an open bottom face 4. Typically, such a sheet is made by casting
a polyethylene resin about metal rod or glass fibre reinforcement. The plan dimensions
of the pallet are typically 0.5 to 1.5 metres wide and 1 to 2 metres front to back.
The pallet is typically from 5 to 10 cm deep vertically and the corrugations are typically
from 4 to 9 cm deep and from 5 to 10 cm wide.
[0022] In use, a load 5 is placed upon the top face of the pallet. A pair of tines 10 of
a fork lift truck are inserted into a pair of the closed top channels 4. When the
tines are raised, they engage the closed top of the channel and lift the pallet and
load with them. If the tines are placed in a pair of open topped channels 3 (as shown
by 10') raising the tines brings them into direct contact with the base of the load
5 so as to lift the load without lifting the pallet. If desired the fork lift mechanism
can have more than two tines, for example as many as seven or eight, so as to increase
and spread the effective load bearing and stiffening surface of the tines. The user
can thus handle the load and pallet together or can separate the load from the pallet.
The unloaded pallet can thus remain upon the flat bed of the road or rail truck in
which it is supplied to the end user for return to the supplier without the need for
the end user to handle the pallet. The wear and tear damage to the pallet during handling
is thus minimised.
[0023] The pallet shown in Figures 2-4 comprises a sheet of reinforced plastic or metal
20 having a plurality of dimples 21, 22 formed therein on a grid pattern. The dimples
21 extend above the plane of the sheet, and the dimples 22 extend below the plane
of the sheet in the manner of an egg box. The dimples provide crossing channels 3,
4 on each side of the sheet so that the tines of the fork lift truck can enter from
any one of the four sides of the pallet. The dimples on the underside of the sheet
form channels with closed tops, those on the upper face of the sheet forming open
topped channels. When a tine is inserted into the channel between dimples on the lower
face of the sheet, it will raise both the sheet and any load carried on the upper
ends of the dimples on the top face of the sheet.
[0024] The tops of the upper dimples 21 form a generally planar load carrying surface which
in this example has a greater area than the bottoms of the lower dimples 22.
[0025] Six channels are illustrated here, allowing access from all four side directions.
Preferably the pallet has between three and ten channels, preferably in each direction.
[0026] Figure 5 shows an attachment for the front end loader of a tractor or for fitting
to the rise and fall mechanism of a fork lift truck. This attachment comprises a support
frame 30 which has mounting hooks 31 for mounting the attachment on a fork lift carriage.
The support frame 30 carries a series of laterally spaced apart projecting tines 10,
the number and spacing of which can be selected to suit the spacing of the channels
3 and 4 in the pallet. Eight tines are illustrated, but the number is preferably between
four and eight. The two outermost tines 10 are mounted slidably to the frame 30 and
can be moved laterally towards or away from their neighbouring tines by hydraulic
rams. Each outermost tine can be brought up into contact with its neighbour so that
they interlock to form a single load bearing member which can fit into a single channel
3, 4. The effective number of tines can therefore be adjusted between 6, 7 and 8 depending
on the number of channels in the pallet to be engaged. Other tines could also be laterally
movable to allow the attachment to accommodate different channel spacings and to square
up the machine or a pallet mounted on the tines 10. Examples of tines which are engaged
with each other are shown in Figure 8. Figure 8a illustrates generally circular section
tines 10a, 10b interlocking, and Figures 8b and 8c illustrate interlocking of, respectively,
three tines 10c, 10d, 10e and two tines 10f and 10g to form effectively single larger
tines.
[0027] If desired, the frame 30 can carry a pusher mechanism 33 which is actuated by an
hydraulic ram 32 or the like to engage with the load 5 on the pallet so that it can
be pushed off the tines 10 when it has been raised off the pallet and onto a suitable
storage or work surface, as illustrated in Figures 6 and 7. The pusher mechanism 33
may be connected to the frame 30 by a straight linkage or a pivoted linkage 35,
via a pivot point 40. Figure 7 also shows an optional pallet engaging member 34 which
can be used to grab an empty pallet and pull it onto the tines 10 of the fork lift.
The pallet engaging member 34 is a hook which held in place in a dimple 22 in the
pallet by a releasable latch mechanism, for example hydraulic, mechanical or electronic.
In this example the latch mechanism is provided by a spring and hydraulically activated
pin.
1. A palletising system for use in the transport and handling of articles or groups of
articles (5), comprising at least one pallet (1, 20) and a fork lift;
the or each pallet (1, 20) comprising a load bearing generally planar surface and
a structure located beneath the plane of the surface having a plurality of channels
(3, 4) therein to receive the tines (10) of a fork lift truck whereby the pallet (1,
20) and its associated load (5) can be handled by the fork lift, the pallet (1, 20)
having alternating closed (4) and open (3) top channels in the structure underlying
the load bearing surface, the open top channels (3) permitting tines (10) of a fork
lift truck when located in at least some of those channels (3) to engage the base
of a load (5) carried upon the pallet directly so that the load can be lifted free
from the pallet, and the close top channels (4) permitting tines (10) of a fork lift
truck when located in at least some of those channels (4) to engage the top of the
channels to raise the pallet and any load carried on the pallet;
the fork lift comprising a plurality of laterally spaced apart tines (10) for engaging
in channels (3, 4) of the pallet, and means for raising and lowering the tines; characterised
in that at least one of the tines (10) is laterally moveable so that when the movable
tine (10) is brought sufficiently close to an adjacent tine (10), both tines may be
inserted into a single channel (3, 4) in the pallet (1, 20).
2. A palletising system as claimed in claim 1, wherein the channels (3, 4) permit entry
of tines (10) from any of four side directions.
3. A palletising system as claimed in claim 2, wherein the pallet has an egg box-like
structure, with the open top channels (3) being defined between upwardly projecting
dimples (21), and the closed top channels (4) being defined between downwardly projecting
dimples (22).
4. A palletising system as claimed in any one of the preceding claims wherein at least
some of the close top channels (4) are open at the bottom.
5. A palletising system as claimed in any one of the preceding claims, wherein at least
one of the open top channels (3) is provided with a hinged top member which can pivot
about a hinge to provide a closed top to the channel (3).
6. A palletising system as claimed in any one of the preceding claims, wherein the laterally
spaced apart tines (10) are mounted on an attachment (30) for the front end loader
of a tractor or the fall and rise mechanism of a fork lift truck.
7. A palletising system as claimed in any one of the preceding claims, wherein the fork
lift has between four and eight tines (10), the two outermost tines being laterally
adjustable so that each can be brought into close proximity or engagement with its
neighbour whereby the effective number of tines can be reduced by one or two.
8. An attachment (30) for the front end loader of a tractor or the fall and rise mechanism
of a fork lift truck, to provide a fork lift suitable for use in the system of claim
1, the attachment comprising a frame (30) which has a plurality of laterally spaced
apart projecting tines (10), at least one of the tines being laterally moveable towards
and away from an adjacent tine (10).
9. An attachment (30) as claimed in claim 8, further including pallet engaging means
(33) for engaging with a surface of a pallet to enable the pallet to be pulled on
to the tines (10) of the attachment.
10. A pallet (1, 20) suitable for use in the palletising system of claim 1, comprising
a load bearing generally planar surface and a structure located beneath the plane
of the surface having a plurality of channels (3, 4) therein to receive the tines
(10) of a fork lift truck whereby the pallet (1, 20) and any associated load (5) can
be handled by the fork lift, the pallet (1, 20) having alternating closed (4) and
open (3) top channels in the structure underlying the load bearing surface, the open
top channels (3) permitting tines (10) of a fork lift truck when located in at least
some of those channels (3) to engage the base of a load (5) carried upon the pallet
directly so that the load can be lifted free from the pallet, and the close top channels
(4) permitting tines (10) of a fork lift truck when located in at least some of those
channels (4) to engage the top of the channels to raise the pallet and any load carried
on the pallet.