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(11) | EP 0 168 252 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Improved packaging |
| (57) A pallet container comprises a carton body (8) formed from stiff folded material,
the base (6, 7) of which supports pallet feet (1,2). The pallet feet are secured in
place by slidably engaging the feet over keyway strips (1a, 1 b, 2a, 2b) which prevent
movement of the feet in directions parallel to the base but normal to the engaging
direction and in the direction away from the base normal thereto. |
[0002] US-A-3026015 discloses a combined packaging carton and supporting pallet which can be made from a blank of stiff but foldable material to provide a carton body of rectangular prismatic form closed at the lower end by an inner pair of opposed end flaps and an outer pair of opposed end flaps and in which the outer pair of opposed end flaps support pallet-foot locating members which, when the carton is erected, are aligned to enable spaced-apart pallet feet to be provided on the underside of the carton body.
[0003] A combined packaging carton and supporting pallet will hereafter be referred to as a "pallet carton".
[0004] Pallet cartons of the kind described in US-A-3026015 can be fabricated in a number of different ways, and one popular method is to make the pallet-foot locating members from rectangular strips of carton material folded to form a tube of rectangular bore and to secure each thus-folded tube to the respective carton flap in its correct position. When this form of pallet carton is erected, the aligned tubes are stiffened and held in alignment by inserting therein slabs of a foamed plastics material. To ensure that the folded tubes are correctly positioned on the end flaps to allow slab insertion, it is known to use a jig.
[0005] The above described method has the advantage that a part of each pallet foot aids in holding the outer flaps in their closed position but has the disadvantage that since each foot is continuous, only two-way entry by the fork of a fork-lift truck under the erected carton is normally possible since the only channels naturally provided on the underside of the carton body for the tines of the fork are running parallel to the elongate direction of the tubes. By perforating the carton tubes and employing specially apertured stiffeners in the carton tubes it is possible to provide for four-way entry, but these are complications which add to the cost of the pallet carton.
[0006] Further, completion of the erection of a pallet carton of the kind described which uses carton tubes for the feet, requires an opening up of each rectangular section tube to accommodate the slabs or other stiffeners and this adds to the erection time.
[0007] This invention is thus concerned with an improved pallet carton which creates the feet in a different way and which thereby yields a carton that is quicker to erect and which, in many configurations, can, without additional expense, provide four-way entry by the fork of a fork-lift truck.
[0008] According to one aspect of the invention a pallet carton comprises a carton body of stiff but foldable material with at least two keyway strips secured to the base of the carton body, each keyway strip being slidably engaged by a foot member in an engaging direction parallel to the base and is then prevented by the respective strip(s) (a) from movement away from the base of the carton and (b) from movement normal to the engaging direction parallel to the base.
[0009] The base of the- carton body would commonly be provided by overlapped inner and outer closure flaps and in this case it is convenient to make each foot member cooperate with a pair of keyway strips which are aligned on opposite outer closure flaps. With this arrangement, the sliding on of a foot member over the two aligned keyway strips on the respective outer flaps holds the base of the carton closed by locking both outer closure flaps in their closed position.
[0010] However the base of the carton can be formed from a single sheet of board material and in this case a single keyway strip can be used for each pallet foot member.
[0011] Normally there will be three foot members secured to the underside of the carton body but two, or more than three, may be used in particular circumstances and all the foot members can be combined into a pallet which slidably engages as an integral unit the keyway strips on the carton base.
[0012] Conveniently each keyway strip has two plane parallel faces one of which is narrower than the other and is secured to the outwardly facing surface of the base of the carton body. Each keyway strip can, for example, have two tapering sides or can be of T-section.
[0013] Each keyway strip may be secured to the carton body by stitching, with or without the use of adhesive. A preferred arrangement for a pallet carton whose carton body has pairs of inner and outer base closure flaps, has three keyway strips on each outer closure flap, one adjacent each side edge of the respective outer flap and one centrally located between the side edges.
[0014] The keyway strips can be of any suitable material and wood or moulded plastics material are preferred.
[0015] The foot members can be of the same material as the keyway strips they slidably cooperate with but this is not essential. Wooden foot members of a generally hollow construction are likely to be of particular commercial importance and provide the required strength and cheapness of manufacture and also permit four-way entry by the lifting tines of a fork-lift truck. Where a wooden foot member includes upper and lower bearer strips spaced apart by blocks, the upper bearer strip (i.e. the one nearest the carton base) can be formed from the side residues of a strip from which the keyway strip(s) was/ were centrally cut.
[0016] The invention will now be further described, by way of example, with reference to the accompanying drawings, in which:-
Figure 1 is an isometric view of part of the underside of the closed end of one embodiment of pallet carton according to the invention showing a pair of aligned keyway strips, and an isometric view of a foot member for the aligned strips,
Figure 2 is a plan of the blank from which the pallet carton of Figure 1 is made,
Figure 3 is an enlarged sectional view of the interengagement between the keyway strips and the foot member in the pallet carton shown in Figures 1 and 2,
Figure 4 shows the underside of the erected pallet carton of Figures 1 and 2 with one foot member in place and another being slid into place, and
Figure 5 is an isometric view of part of the underside of a second pallet carton according to the invention showing a complete pallet about to be attached via three keyway strip assemblies of different format.
Figure 4 of the accompanying drawings shows the underside of a first embodiment of erected pallet carton. Two of the three pallet feet are shown at 1 and 2 and each is formed from aligned keyway strips la, 1b and 2a, 2b and slid-on hollow foot members 4 and 5. The strips la.....2b are secured to outer end flaps 6 and 7 of the carton body 8. The location of a third foot is shown by the strips 3a, 3b but the foot member to engage these has not been shown.
[0017] Figure 2 shows the blank 8' for the carton body 8 with the outer flaps 6 and 7 and two inner flaps 10 and 11. Since this is conventional it is not thought necessary to describe it in further detail. The location of the keyway strips la....3b is shown by the dotted lines in Figure 2.
[0018] Figure 1 shows the two keyway strips la, 1b in the position they adopt in the partially erected carton, prior to sliding the foot member 4 over them. The foot member 4 is also shown and will be seen to be made from a pair of locking strips 12a, 12b, a base plate 13 and three spacer blocks 14a, 14b and 14c. The strips 12a, 12b are chamfered on their confronting edges to lockingly engage with the pair of aligned keyway strips la, lb and the pallet carton rests on the base plate 13 with gaps 15 between the blocks 14a/b and 14b/c providing access for tines of a fork-lift truck.
[0019] The overall length of the foot member 4 in Figure 1 is shown as X and suitable lengths of the keyway strips la, lb to be used with such a foot member are also shown.
[0020] Figure 3 shows, in mm, transverse dimensions for the keyway strips la, lb and the locking strips 12a, 12b which are suitable for a pallet carton having keyway strips and foot members of soft wood.
[0021] The keyway strips can be prefixed to the carton blank so that erection does not involve any fixing of these strips to the blank, but it is also possible to supply the carton in knocked-down condition with the location of the keyway strips marked to allow the user to secure the strips in place by stitching (i.e. with wire staples 16) or by use of an adhesive. A cover-strip protected self-adhesive layer can be applied to each strip la....3b to facilitate this user-application of the strips.
[0022] Each foot member clearly locks the outer flaps 6, 7 in their closed condition without the need for banding of the carton in some cases. Although separate foot members are shown in Figures 1 and 4, it will be appreciated that these can be combined into a pallet (as will shortly be described with reference to Figure 5) should this be required.
[0024] Figure 5 shows a one-piece base 20 of a container \ 21 which has the side walls 21a, 21b folded up therefrom. Three foot members 24, 25 and 26 are linked together to form an integral pallet 23 and this is secured on the base 20 by engagement of keyway strips (22a, 22b and 22c) in grooves 27a, 27b and 27c in the underside (as shown in Figure 5) of the respective foot members. The carton body/pallet engagement is effected by relative sliding motion in the direction of the arrow A in Figure 5 and following engagement of the keyway strips 22a...c in the grooves 27a....c, the pallet cannot be moved relative to the base 20 in either direction normal to A.
[0025] Figure 5 shows three formats of keyway strip to indicate that various arrangements are possible. Wire stitches 16 are shown in Figure 5 but these are not essential. It will be noted that keyway strips 22c are of T-cross section and this is one possible alternative to the tapering sides of the strips shown elsewhere.
[0026] The grooves 27 may stop short of one end of the foot members 24-26 to permit sliding engagement from one end only (and thus a reduced possibility of inadvertent slippage between the carton body 21 and pallet 23 during use). Similar stopped end grooves can be used with the single foot members 4, 5 of Figures 1 and 4.
[0027] The pallet 23 could be banded to the carton 21 after attachment and also provides four-way entry to the tines of a fork truck.
[0028] Among the advantages of a pallet container in accordance with the invention may be mentioned
1. There is no risk of moisture degrading the foot members since these can be of non-card material.
2. Four-way tine entry is easy to arrange.
3. Less carton material is required than with prior art designs in which carton tubes are used for the pallet feet.
4. By making the foot members of a material which is substantially non-compressible under the loads arising in practice, there is no possibility of a foot member becoming misshapen due to excessive loading as has happened with carton tubes stiffened with foam material.
5. By using a complete slip-on pallet, the concept of reusable pallets becomes a realistic possibility.
1. A combined packaging carton and supporting pallet made from a blank of stiff but
foldable material to provide a carton body (8) closed at its base by at least one
outer end flap (6, 7, 20) and a plurality of pallet feet (1, 2, 24-26) provided on
the underside of said at least one outer end flap (6, 7, 20), characterised in that
at least two keyway strips (la, lb, 22a) are secured to the base of the carton body,
each keyway strip being slidably engaged by a foot member (1, 2, 24-26) in an engaging
direction parallel to the base and is then prevented by the respective strip(s) (a)
from moving away from the base normal thereto and (b) from moving normal to the engaging
direction and parallel to the base.
-2. A pallet container as claimed in claim 1, in which the base of the carton body
is provided by overlapped inner (10, 11) and outer closure flaps (6, 7) characterised
in that each foot member (1, 2) cooperates with a pair of keyway strips (la, lb:2a,
2b) which are aligned on opposite outer closure flaps (6, 7).
3. A pallet container as claimed in claim 1, in which the base of the carton is formed
from a single sheet (20) of board material, characterised in that a single (22a) keyway
strip is used for each pallet foot member (24-26).
4. A pallet container as claimed in claim 1, characterised in that the foot members
are combined into a pallet (23) which slidably .engages as an integral unit all the
keyway strips (22a, 22b, 22c) on the carton base (20).
5. A pallet container as claimed in any preceding claim, characterised in that each
keyway strip (la-3b; 22) has two plane parallel faces, one of which is narrower than
the other and is secured to the outwardly facing surface (6, 7; 20) of the base of
the carton body (8).
6. A pallet container as claimed in claim 5, characterised in that each keyway strip
is shaped as a frustum of a rectangular prism having two tapering side faces.
7. A pallet container as claimed in any preceding claim, charactc:rised in that each
keyway strip is made of wood and is secured to the base of the carton body by stitching
(16), with or without the use of adhesive.
8. A pallet container as claimed in claim 7, characterised in that the foot members
(1, 2; 24-26) are of hollow construction and permit four-way entry by the lifting
tines of a fork-lift truck.
9. A pallet container as claimed in any preceding claim, characterised in that each
foot member (1, 2; 24-26) includes upper (12) and lower (13) bearer strips spaced
apart by blocks (14), the upper bearer strip (12) being formed from the side residues
(12a, 12b) of a strip from which the keyway strips(s) (la, lb) was/were centrally
cut.
10. A pallet container as claimed in claim 1, characterised in that the carton body
is supplied in knocked-down condition and the keyway strips supplied separately, the
location of the keyway strips being marked on the blank to allow the user to secure
the strips in place.