[0001] This invention relates to a container and a base therefor and more specifically to
a base for a container for carrying large quantities of chemicals, powders, granules,
semi-liquids, liquids, or similar products. It will be appreciated, however, that
the container could be used for many other different purposes.
[0002] In the recent past, especially with the advent of containerisation, it has been normal
to transport bulk chemicals, and for that matter many other granular, powdered and
even liquid materials, in what are knwon as Intermediate Bulk Containers (IBCs). IBCs
normally comprise some form of box which may be made of multi-layer corrugated fibrous
material of largely traditional construction which is supported on a traditional pallet
base. Normally a liner is provided within the box. While such IBCs have been commercially
acceptable they do suffer from certain disadvantages, one being that traditional pallets
are normally of slatted construction and hence are not waterproof. This means that
under certain conditions the base at least of the fibrous box on the pallet can easily
get wet and lead to failure of the container. To some extent this problem can be reduced
by incorporating a waterproof laminate in the corrugated material of the box or by
treating the box in some way so as to make it at least water resistant.
[0003] Other disadvantages associated with traditional IBCs are that the pallets are relatively
heavy, have a limited life, are bulky and have to be provided with various means for
locating the box on them. Furthermore, the box itself has to be provided with a traditional
base even though the pallet on which the box will rest is normally sufficiently strong
to support the contents of the box. This base can be formed either from a separate
lower end cap or from the traditional end flaps foldably connected to the lower edges
of the side walls of the box.
[0004] The disadvantages of wooden pallets for use in conjunction with corrugated fibrous
boxes are known, and it has been proposed in US-A-4550830 to use a plastics pallet
having a groove around its periphery which receives the bottom edge of a sleeve of
corrugated fibrous material. The plastics base is vacuum formed from two sheets of
polymeric material, and apertures are provided in each layer through which tabs on
the sleeve may be passed, and then folded over, to attach the sleeve to the pallet.
In this construction, it is suggested that the problem of transferring compressive
forces from the sides of the container resulting from the weight of other containers
stacked on top, to the pallet without it deforming, is solved. To achieve this, the
compressive forces are said to be transferred substantially directly to the supporting
surface, e.g. a warehouse floor, thereby minimising deformation of peripheral portions
of the pallet. In fact, this problem is not solved satisfactorily with this prior
art proposal, because of the way the pallet is formed. The groove is formed in the
upper layer of the pallet only, and because the pallet is vacuum formed from two sheets,
there is a small clearance between the under or inner side of the top sheet and the
upper or inner side of the bottom sheet, which means that the groove is not supported
on the supporting surface until the top sheet has deformed very slightly.
[0005] There is a further major problem with this prior art container, in that the corrugated
fibrous sleeves, when the containers are stacked in the open air, at least of those
containers on the ground, easily get wet and thus the sleeves totally lose their stacking
strength. This is because the pallets are not waterproof from beneath, because of
the apertures therein for the locking tabs. This means that if put down by a fork
lift truck into a shallow puddle, there is a real risk of the container and its contents
getting damaged. Furthermore, even upper containers in a stack can get wet, since
water can collect in the groove of a top of a container on which another container
is stacked, and this water can then penetrate through the apertures of the base of
this other container.
[0006] We have now developed an improved container and pallet base which does overcome the
stacking problem, and which does not suffer from the disadvantages mentioned above.
[0007] According to the broadest concept of the present invention, we provide a base for
a container comprising a platform having on its upper face a groove extending around
or adjacent the periphery of the platform to receive the lower edge of the or each
side wall of the container, the underside of the platform being suitably shaped to
enable a loaded base to be handled with a forklift truck or the like, wherein the
platform is formed in one piece, and in which the groove is continuous and devoid
of apertures therein, so that the base provides a completely waterproof barrier to
prevent water and moisture from penetrating the base from its underside and reaching
the lower edges(s) of a sleeve when one is located in said groove.
[0008] It is preferred that portions of the base in which the groove is formed provide support
areas for the base so that they will bear directly on a flat support surface for the
base.
[0009] Also according to the present invention, we provide a container comprising a base
as described above, at least one side wall extending upwardly from the base, the lower
edge of the or each side wall being located within and constrained by the groove in
the upper face of the platform and a lid for the container which may be formed by
means of integral flaps or a separate top.
[0010] Preferably, a liner is located within the container and is confined by the or each
side wall.
[0011] Preferably, the base is formed from a synthetic resinous material, e.g. by means
of a vacuum forming, rotational (or spin) moulding, or blow-moulding process, and
is shaped on its underside so as to provide a four-way entry for the forks of a forklift
truck.
[0012] That portion of the upper face of the platform located within the groove is preferably
flat, but alternatively it could be dished so that its centre is at the same level
as the periphery on the underside so that it can assist in supporting the contents
of the container. This also has the advantage of lowering the centre of gravity of
a filled container. Furthermore, the platform may be shaped at each corner to support
internal or external supports to provide extra strength for when similar containers
are stacked one upon another and/or to enable the strength of the side walls which
would normally be made of corrugated fibreboard to be reduced.
[0013] If desired, a central area of the platform may be formed with one or more lines of
weakness to enable a central panel to be removed from the platform to allow central
discharge of the contents of the container.
[0014] The base may incorporate ribs therein to increase its strength or alternatively to
allow it to be formed from thinner material.
[0015] It is also envisaged that the container may be provided with a formed one-piece lid
of similar material to the base and it is also envisaged that the lid could be connected
to the base by means of a synthetic resinous sleeve bonded between the base and lid,
suitable side walls subsequently being located within the groove in the base to form
the container.
[0016] Normally, the base would be square in plan but it could be of different rectangular
shape or in certain instances round or multi-sided, for example, octagonal or hexagonal.
Normally, the stacking strength of a container is increased in relation to the number
of vertically extending folds in its side wall.
[0017] Several embodiments of the invention are now described by way of example with reference
to the accompanying drawings, in which:-
FIGURE l is a perspective schematic view of one embodiment of moulded container base
showing the lower portion of the side walls of the container about to be fitted to
the base;
FIGURE 2 is a plan view of an alternative construction of container base;
FIGURE 3 is a half sectional elevation on the line X-X of the base shown in Figure
2;
FIGURES 4 and 5 show respectively perspective schematic views of two further alternative
embodiments of container and base therfor, and
FIGURE 6 is a view similar to Figure l showing a yet further alternative construction
of base and side walls for assembly therewith.
[0018] In the drawings, like parts in the various different views are identified with the
same reference numerals.
[0019] Referring now to Figure l, there is shown a moulded synthetic resinous base l having
on its upper face a platform 3 around the periphery of which is formed a continuous
upward facing groove 5. The base is provided on its lower face with intersecting channels
7 extending between opposite side edges of the base of sufficient size and of the
required spacing to allow four-way entry of the forks of a forklift truck for handling
purposes, the base otherwise having a lower peripheral edge portion 9 for resting
on a suitable support surface. The base is formed in one piece, for example by a vacuum
forming or blow- or spin-moulding technique, and is formed of a material which is
sufficiently strong to support loads of at least 500kg without excessive buckling
and it should also be hardwearing and able to withstand extremes of temperature. Suitable
materials for the base are, e.g. high impact A.B.S. and high impact polyethylene and
certain similar recycled material.
[0020] The base is designed to form the bottom of a container such as an Intermediate Bulk
Container, two of the side walls of which are shown at ll and l3. Although it is envisaged
that these side walls could be made of many different materials, it is preferred for
cost purposes that they are made of multi-wall corrugated fibreboard which may incorporate
a barrier laminate or be treated in some other way so as to be water-resistant. Figure
l shows a rectangular container but other shapes are of course possible. The container
shown in Figure l therefore has two pairs of opposite side walls which are formed
into a rectangular sleeve in known manner. The groove 5 in the base l extends the
full depth of the base, save for the thickness of the material of the base at its
bottom edge 9, and is of a width sufficient snugly to receive and confine the lower
edges of the side walls ll and l3 (and those not ilIustrated). These lower edges are
therefore provided with cut-outs l5 to accommodate the material defining the channels
7 in the base. Of course, if the four side walls of the container are held in their
sleeve formation with the aid of a glue or stapling flap, provision for accommodating
this should be made in the groove 5.Alternatively, the extra thickness of board material
may be omitted where the bottom edge of the sleeve locates in the groove 5.
[0021] The construction shown in Figures 2 and 3 differs from that of Figure l in that instead
of having a flat central platform 3, a dished platform 30 is provided within the continuous
peripheral groove 5. Accordingly, the platform has a first inwardly and downwardly
inclined portion 3l closely adjacent each edge of the base merging with a flat region
33 which forms the upper surface of that portion of the wall of the base which defines
the top of the intersecting channels 7. The flat portions 33 merge with further downwardly
and inwardly inclined portions 35, the inner edges of which are connected to a rectangular
central portion 37, the lower face of which is at the same level as the lower edge
9 of the side walls of the base. In this construction, therefore, a load on the base
is supported centrally by the rectangular portion 37 as well as peripherally by the
edges 9. It will be appreciated that rectangular portion 37 could be of a different
shape, and that the relative sizes and shapes and inclinations of the various portions
making up the platform may be different from those illustrated.
[0022] In the construction shown in Figure 4, an assembled container is illustrated in which
the top edges of the side walls are provided with inwardly turned flaps l7. The base
l differs from that shown in Figure l in that it is specially formed with projecting
portions 4l to receive external corner supports 43 extending upwardly to the same
height as the side walls ll and l3 of the container. These supports may be formed
in any traditional manner, e.g. from strips of timber nailed together so as to have
a fixed together, right-angled section which can be used to embrace the four corners
of the container, thus providing protection for the container. Their main purpose,
however, is to provide stacking strength and while their lower ends are of course
confined by the portions 4l of the base, their upper ends are held in contact with
the container side walls by means of one or more straps 45.
[0023] In the construction shown in Figure 5, a container and base l provided with internal
stacking supports 47 is shown. The lower ends of the supports 47 are accommodated
in suitable sockets (not shown) formed in the upper face of the base l and the supports
47 are otherwise maintained in their upright positions in the corners of the container
by straps of corrugated fibreboard 49 formed out of the material of the side walls
of the container in known manner.
[0024] Figure 6 shows an octagonal container and base therefor. In other repsects the container
and base incorporate some of the features of the construction shown in Figure l and
some of the features of the construction shown in Figures 2 and 3 but in this case
eight intersecting channels 70 are provided in the base and there are of course eight
side walls upstanding from the continuous octagonal groove 5 in the base l. The additional
number of fold lines separating adjacent side wall panels from each other gives added
stacking strength to the container.
[0025] The above described containers can of course be of any size but they are particularly
designed for use as Intermediate Bulk Containers capable of carrying at least 500kg
of powdered, granular or liquid material. Normally, the containers are provided with
an internal liner bag which will rest upon the platform of the base and when filled
can simply be tied off or sealed in some other manner at the top. The container can
then be closed in known manner either by folding in integral top closure flaps or
by fitting a cap on top. The filled container would then normally be connected to
the base l using straps or the like.
[0026] In order to reduce ingress of dust, dirt, water and the like into the groove 5 when
the container is in use, it is preferred that a wide strip of self-adhesive tape be
applied to the joint between the side walls(s) and the base so as completely to seal
the joint. This means that any material hitting a side wall of the container will
not fall down into the groove 5 but instead will slide down the side edge of the base
onto the ground.
[0027] From the foregoing it will be appreciated that the present invention provides a new
construction of base for a container and container with base and the one piece formed
plastics base is wholly waterproof from its underside and thus even if a filled container
is dropped into a pool of water, any water splashing upwardly cannot seriously damage
the container.Furthermore, because the base is solid and forms the bottom of the container
and also confines the bottom of the side walls of the container, it is not necessry
to provide bottom closure panels on the side walls of the container. Furthermore,
because of their construction, the bases are just as strong as wooden pallets but
need not be so heavy and although individual bases are of the same order of size as
individual wooden pallets, the bases of the present invention will almost completely
nest one within another and hence when not in use can be stacked very compactly. Also,
the side walls of the container with which the bases are to be used can be folded
flat until required. The side walls can be formed from triple fluted corrugated board
and are therefore very strong. Furthermore, because their bottom edges are formed
to fit within the groove 5, portions of the bottom edge between the cut out l5 rest
in portions of the groove 5 which themselves rest on a support surface for the platform,
e.g. directly on the ground. This provides a 'pallet-box' with substantial stacking
strength.
[0028] Furthermore, since the bases are formed by a moulding or forming operation it is
possible specifically to design them to accommodate internal or external stacking
supports to increase stacking strength even more. With a traditional wooden pallet,
complicated measures have to be taken to locate stacking supports, e.g. the provision
of special metal attachments or the like.
[0029] A further advantage with the bases of the present invention is that for heavy materials
they can be provided with a dished platform, the centre of which can be at the same
level as the periphery of the base, thereby providing additional support for the contents
of the base and its container and at the same time lowering the centre of gravity
of a filled container. It is almost impossible to do this with a traditional pallet.
Furthermore, such dished bases can be specially formed with lines of weakness to assist
with central discharge should this be desired, e.g. for free-flowing dry goods, liquids
or semi-liquids.
[0030] It is also envisaged that the bases of the present invention could be used in conjunction
with pre-formed or moulded tops which could be connected to the bases with plastics
sleeves which would be bonded at their ends to the base and top respectively, thereby
providing a waterproof or powder-proof container. The bases with their connected tops,
when empty, could be stacked relatively compactly and when they are required for use,
side walls could be fitted, thereby effectively acting to confine the plastics sleeve
and providing spacers to space the tops, which would have a removable lid, from the
bases.
[0031] A further advantage of the present invention is that the bases would have a longer
life than timber pallets, would be economical to re-use in that they can be nested
together and returned to the original supplier who would fit new side walls, and they
can be kept much cleaner and will therefore be more hygenic than wooden pallets.
[0032] It is envisaged that strength of the base could be maintained by reducing the thickness
of the material of the base and building ribs into the material; alternatively, the
ribs could be used to increase the strength of the base. Furthermore, it is preferred
that mid-way along each edge of the base and at the corners, enlarged recesses 80,8l
(see Figure 2) are provided which merge with the groove 5. These make the base easier
to mould, and easier to stack when empty. They can also assist with locating a filler
liner within the sleeve on the base.
[0033] It will of course be understood that the present invention has been described above
purely by way of example, and modifications of detail can be made within the scope
of the invention.
[0034] For example, the underside of the platform 3 could be level with the top of the channels
7. This would mean the top of the platform 3 would be located below the upper peripheral
edge of the base l.
[0035] Furthermore, the construction shown in Figure 6 may have only two pairs of channels
70 intersecting at right angles to provide traditional four-way entry for a forklift
truck's forks.
1. A base for a container, said base comprising a platform (l) having on its upper
face (3) a groove (5) extending around or adjacent the periphery of the platform to
receive the lower edge of the or each side wall (ll,l3) of the container, the underside
of the platform being suitably shaped (at 7) to enable a loaded base to be handled
with a forklift truck or the like, characterised in that the platform (l) is formed
in one piece, and that the groove (5) is continuous and devoid of apertures therein,
so that the base provides a completely waterproof barrier to prevent water and moisture
from penetrating the base from its underside and reaching the lower edge(s) of a sleeve
(ll,l3) when one is located in said groove (5).
2. A base according to claim l characterised in that portions of the base (l) in which
the groove (5) is formed provide support areas for the base so that they will bear
directly on a flat support surface for the base (l).
3. A container comprising a base (l) as claimed in claim l, at least one side wall
(ll,l3) extending upwardly from the base, the lower edge of the or each side wall
(ll,l3) being located within and constrained by the groove (5) in the upper face (3)
of the platform (l) and a lid (not shown) for the container.
4. The invention as claimed in claim l, 2 or 3 characterised in that the base is formed
from a synthetic resinous material and is shaped on its underside (at 7 or 70) so
as to provide four-way entry for the forks of a forklift truck.
5. The invention as claimed in any one of claims l-4 characterised in that that portion
of the upper face of the platform (3) located within the groove (5) is flat (Figure
l).
6. The invention as claimed in any one of claims l-4 characterised in that portions
of the upper face of the platform (3) located within the groove (5) is dished (30,
Figures 2,3) so that its centre is at the same level as the periphery on the underside
of the base so that it can assist in supporting the contents of the container.
7. The invention as claimed in any one of claims l-6 characterised in that the platform
(3) is shaped at each corner (4l) to support internal (47) or external (43) supports
to enable similar containers to be stacked one upon another and/or to enable the strength
of the side walls (ll,l3) which would normally be made of corrugated fibreboard to
be reduced.
8. The invention as claimed in any one of claims l-7 characterised in that a central
area (37) of the platform (3) is formed with one or more lines of weakness to enable
a central panel to be removed from the platform to allow central discharge of the
contents of the container.
9. The invention as claimed in any one of the preceding claims characterised in that
ribs (not shown) are incorporated in the base to increase its strength or alternatively
to allow it to be formed from thinner material.
l0. The invention as claimed in any one of the preceding claims characterised in that
the container is provided with a formed one-piece lid of similar material to the base
and the lid is connected to the base by means of a synthetic resinous sleeve bonded
between the base and lid (not shown).