GB2265606A

GB2265606A - Fibreboard tray

Info

Publication number: GB2265606A
Application number: GB9306293A
Authority: GB
Inventors: Clifford White Kelso
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-04-03
Filing date: 1993-03-26
Publication date: 1993-10-06
Also published as: GB9306293D0

Abstract

A fruit and vegetable tray comprising a base (1), side walls (2, 3) and corner posts (4) formed by folding from a fibreboard blank, the corner posts (4) being formed by folding adjacent parallel panels (7, 8, 9) provided as extensions on one of the sides (2) of the tray into a tube. The upper end of the posts (4) are held together and connected to an adjacent side wall (3) by a cap of plastics material, and locking means (10, 11, 13 to 17) formed as an integral part of the fibreboard blank secures each corner post (11) with respect to an adjacent side wall (2, 3) and/or the base (1) of the tray. <IMAGE>

Description

FIBREBOARD TRAY Fruit and vegetables are often packed in shallow trays with posts up-standing at each corner so that trays can be stacked one on top of another without damaging the contents.

Traditionally such trays were made from wood with solid wooden corner pieces but recently such trays have been made from fibreboard. When such trays are made from fibreboard they are folded from a blank with the corner posts formed by folded fibreboard tubes usually having a triangular cross section. The trays also include a triangular plastics cap which is jammed onto the top of each tubular corner post to maintain it in its folded configuration and to join the adjacent side walls of the tray together. The plastics cap usually includes an upstanding spigot which engages in a socket formed in the base of a corresponding tray stacked above. An example of such a box is described in GB-A-2,185,964.

Such boxes can hold anything from lettuces to citrus fruits or root vegetables. Typically they can contain up to ten or fifteen kilogrammes of fruit or vegetables and accordingly when a number of such boxes are stacked one above the other it is important that they are stable and that the corner posts on the lower most box can accept the load imposed upon them by all of the boxes stacked above.

According to the present invention, a tray comprising a base, side walls and corner posts is formed by folding from a fibreboard blank, the corner posts being formed by folding adjacent parallel panels provided as extensions on one of the sides of the tray into a tube, the upper end of the posts being held together and connected to an adjacent side wall by a cap of plastics material, and locking means formed as an integral part of the fibreboard blank which, in use, secures each cornor post with respect to an adjacent side wall and/orthe base of the tray.

When the trays are heavily loaded there is a tendency for the sides of the tray to splay outwards with the result that the corner posts can also tend to splay outwards.

Particularly when such boxes splay outwards in this way the corner posts tend to unfold and the greater the applied load the greater tendency'there is for the corner posts to fail. Locking means of a first type may comprise an aperture provided in the base of the box which receives and locates the lower end of the tubular corner posts. This firstly holds the lower end of the corner post positively into their folded configuration and secondly tends to stop the lower end of the corner posts moving inwards towards the middle of the box and so helps resist the outward splay of the side walls. Thus, by positively locating the lower end of each corner post, the carrying capacity of each tray is enhanced so enabling the trays to carry a greater capacity or, alternatively, enabling the trays to be made from lighter gauge material and still have the same carrying capacity.

Preferably the aperture to hold the lower end of the tubular corner post is combined with a socket which in use receives a spigot formed on the top of the plastics cap.

The lower part of each corner post may include a projection which engages in the aperture in the base of the tray or the aperture may be formed to contain the whole of the lower portion of the tubular corner post.

Alternatively, the tray may include locking means of a second type formed as an integral part of the fibreboard blank to enable the adjacent side wall and the corner post on the one side wall to hold together without the plastics cap.

Typically the fibreboard trays are erected from the blanks on site, immediately before being filled with fruit or vegetables. The locking means of this second type enables each corner of the box to be held together as it is folded and erected so that the box keeps its erect form as each corner is made and before the plastics caps are fitted to the erected tray. Another considerable advantage of the second type of locking means is during use of the boxes since, as the filled boxes are stacked one on top of another and unstacked it is relatively easy to dislodge one of the plastics caps. When this happens to a conventional box since the two side walls are no longer connected together at the corner, there is a tendency for the side walls to splay apart and allow the contents to escape and the stack containing such a box to fail and tip over.When the trays include locking means of this second type, the adjacent sides of the box are held together and the integrity of the tray is maintained even if a plastics cap is dislodged.

The locking means may be formed by a pair of slits in adjacent portions of the tubular corner post and side wall arranged in a dove-tailed configuration so that the dovetailed key so formed can be pushed inwards into the dovetailed slot in the tubular corner post and thereby lock the side wall into the corner post. The key need not be a dove-tailed shape. For example, it may also be formed in the shape of a necked tab.

An alternative configuration of the locking means is for the corner post to include a dove-tailed or necked key and the adjacent side wall include an inverted T-shaped slit cut into it so that the key can be pushed inwards into the section which is then pushed back over the key thus positively locking the two components together.

Another alternative configuration of the locking means is for the corner.post to include a circular aperture and the adjacent side wall include a C-shaped slit cut into it so that the fibreboard inside the C-shape slit can be folded and pressed into the aperture in the corner post again to provide a key which holds the two components together.

Preferably the tubular corner posts are triangular in cross section and, in this case, it is preferably just the panel forming the hypotenuse of the corner posts which is locked into position into the aperture in the base of the tray.

Preferably the tray in accordance with this invention also includes both the first and second types of locking means and this provides a particularly robust and secure tray which not only has an increased carrying capacity but is far more durable in use.

A particular example of a tray in accordance with both aspects of the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a corner of the tray as seen from inside and above; Figure 2 is a corner of the blank before erection; Figure 3 is a fragmentary perspective view of the top of a corner post with the plastics cap removed to show one example of the locking means; and Figure 4 is a fragmentary perspective view of the top of a corner post with the plastics cap removed to show another example of the locking means.

Figure 1 shows a corner of a rectangular fibreboard tray comprising a base 1, a longitudinal side wall 2 and an end side wall 3. The tray includes a triangular section corner post 4 surmounted by a generally triangular plastics cap 5 including an up-standing spigot 6.

The tray is formed from a twin or triple ply, corrugated fibreboard blank shown most clearly in Figure 2.

The corner post 4 is formed by three parallel panels 7, 8 and 9 which are formed as an extension of the longitudinal side wall 2. "Valley" fold lines, indicated by chain dotted lines in Figure 2, are provided between adjacent panels 7, 8 and 9 and the corner post 4 and between the side walls 2 and 3 and the base 1. The central panel 8 which forms the hypotenuse of the corner post 4 includes an integral projecting tab 10. The corner of the base 1 includes a parallel sided slot 11 which merges with a Dshaped aperture 12. Slots 13 and 14 in the panel 7 are arranged in a dove-tail configuration and slots 15 and 16, which are also arranged in a dove-tail configuration, are provided in the end wall 3 to define a dove-tailed key 17.

Slot 18 is also provided in the side wall 2.

To erect a fibreboard tray in accordance with this invention the panel 9 is folded towards the panel 8 and then these two panels folded towards the panel 7 to form a triangular tube. The resulting triangular tube is then folded until the panel 9 lies against the side wall 2. The side wall 2 is then raised so that it forms a right angle with the base 1. As the side wall 2 is folded upwards the projecting tab 10 of the panel 8 enters and engages the parallel sided slot 11 on the base 1. The end wall 3 is then raised to form a right angle with the base 1 and to rest against the side of the panel 7 of the corner post 4.

With both the side wall 2 and the end wall 3 held in this position the dove-tailed shaped key 17 is pushed inwards into the middle of the tubular corner post 4 folding the board between the slots 13 and 14 inwards to provide a dove-tailed aperture. As the dove-tail shaped key 17 is folded downwards into the inside of the tubular corner post 4 it locks against the sides of the dove-tailed aperture formed by the slots 13 and 14 in the panel 5 to hold the end wall 3 onto the corner post 4 to keep the side walls 2 and 3 erected. Subsequently the plastics cap 5 is fitted on top of the tubular corner post 4 covering the top of the end wall 3 and side wall 2 and fits into the slot 18. The spigot 6 in the top of the plastics cap 5 in use enters the D-shaped opening 12 in the base 1 of a box stacked on top of it.

Figure 4 shows an alternative locking means in which the slots 13 and 14 in panel 7 are cut to form an inverted "T" section. In this example, the dove-tailed shaped key 17 formed in the side wall 3 is folded inwards into the inverted "T" section which is then pushed back over the dove-tailed key 17, thus positively locking the side walls 2 and 3 together at the corner post.

Claims

1. A fruit and vegetable tray comprising a base, side walls and corner posts formed by folding from a fibreboard blank, the corner posts being formed by folding adjacent parallel panels provided as extensions on one of the sides of the tray into a tube, the upper end of the posts being held together and connected to an adjacent side wall by a cap of plastics material, and locking means formed as an integral part of the fibreboard blank which, in use, secures each corner post with respect to an adjacent side wall and/or the base of the tray.

2. A tray according to claim 1, in which the locking means comprises a projection formed in the lower part of each corner post which engages in an aperture formed in the base of the tray.

3. A tray according to claim 2, in which the whole of the lower portion of the tubular corner post engages in the aperture formed in the base of the tray.

4. A tray according to claim 2, in which the tubular corner posts are triangular in cross section and only the panel forming the hypotenuse of the corner posts includes a projection which is locked into position into the aperture formed in the base of the tray.

5. A tray according to claim 2, 3 or 4, in which the aperture to hold the lower end of the tubular corner post is combined with a socket which, in use, is capable of receiving a spigot formed on the top of the plastics cap of a substantially identical box stacked below.

6. A tray according to any preceding claim in which the locking means comprises slits in adjacent portions of the tubular corner post and side wall cut in a pre-determined configuration so that, in use, a key so formed in the side wall can be pushed inwards into the slot in the tubular corner post and thereby lock the side wall into the corner post.

7. A tray according to claim 6, in which the key formed in the side wall is in the shape of one of a dove-tail or necked tab.

8. A tray according to claim 6 or 7, in which the slot cut in the corner post is in the shape of an inverted T section so that, in use, the key can be pushed inwards into the section which is then pushed back over the key thus positively locking the two components together.

9. A tray according any one of claims 1 to 5, in which the locking means comprises a circular aperture cut in the corner post and a C-shaped slit cut into the adjacent side wall so that, in use, the fibreboard inside the C-shaped slit can be folded and pressed into the aperture in the corner post to provide a key which holds the two components together.

10. A tray substantially as described with reference to Figures 1 to 4 of the drawings.