GB2504067A - A tray made of a single blank having reinforced corners - Google Patents

Abstract

Tray (200, figure 3) and single continuous blank (200, figure 4) for forming tray 200, having base panel 210, end panels 220, side panels 230, and four corners with reinforcement sections 240. Reinforcement sections 240 provide a secondary wall thickness 260 and a prismatic section 250, the prism preferably being elongate, of triangular cross section, and connected to the side panel. The reinforcement sections may be self locking, possibly using tabs and slots 280, 290, preferably using no adhesive or staple to fix the folded blank. The unfolded shape of the blank may be square or rectangular. Four flat, generally triangular stacking surfaces 300a may be provided at each corner of the tray, and each side panel 230 may comprise a recess in its upper edge 310. Side panels 230 may have two square panels 300 which fold into triangular stacking surfaces 300a. A method for folding is also included.

Description

I

Improved Tray Trays, and in particular corrugated cardboard trays, are used worldwide for transporting, storing and displaying a wide range of goods. Traditionally, such trays comprise a base panel and four additional panels perpendicular to the base to create the sides of the tray; some designs incorporate additional panels which provide a lid.

These trays are usually manufactured out of a corrugated material, such as corrugated cardboard, as it is lightweight and relatively strong. Further, many such materials are readily recyclable.

Due to the number of trays required, the manufacturing process is closely monitored and streamlined to minimise inefficiencies. It is preferred, therefore, that each tray is made out of a single blank, i.e. using only one continuous piece of material, e.g. cardboard. The layout of the blank is also carefully monitored and designed to minimise wasted space.

One problem with certain types of tray is that they do not meet this requirement of being made from a single blank since to increase their maximum compressive strength (important for example during stacking) they often use or require multiple pieces of cardboard to be folded and assembled together. Alternative designs that avoid this by using a single blank might then not make efficient use of the material space, or of the space within the finished tray, and so result in increased material wastage, or inefficiencies in the useable loading space. Both of these increase either or both manufacturing costs and complexity per unit build.

The majority of trays that are assembled from one or more blanks of material are self-locking, i.e. the respective parts lock into place once correctly folded and oriented. This is usually achieved through the use of a series of tabs and slots which, once in a folded position, align and engage to prevent the tray from unfolding and reverting back towards the unfolded (i.e. blank) state. Using this method, the need for extra processing steps, such as gluing or stapling, to fix or lock the tray in a folded state is avoided or minimised.

Trays as described above are used to transport a wide range of manufactured goods as well as natural produce such as fruit and vegetables. En these applications, it is often the case that multiple trays need to be stacked on top of each other. In addition to having a suitably high compressive strength to cope, this stacking requirement also requires a tray to provide a suitable, usually fiat, top and bottom surface for allowing the stacked arrangement to be sufficiently strong and stable to support the load of the trays above it both once stacked and during the stacking/transportation processes.

Current tray designs achieve the strength required through the use of reinforced corners. Many popular designs rely on either a separate insert, or a folding panel or tab to double the thicknesses around the corner, increasing the maximum compressive strength. Unfortunately such designs, where achieved using a single blank, often result in a flat ledge surface extending inwards from the side or end panels -and usually along the whole length of that side or end panel. While a flat surface is required to facilitate stacking, a ledge running the entire length of a side or end panel is undesirable as it is cumbersome and makes accessing the products more difficult. An alternative solution wourd therefore be beneficial.

Other designs have incorporated a prismatic section into each corner, often a triangular prismatic section, either as a chamfering of the corner of the tray or as a separate member within the inside of the corner of the box,. This increases the vertical compressive strength of the tray significantly, and often by more than simply doubling the thicknesses of the walls, but it is more compticated to manufacture. Nevertheless, many designs are forced to rely on a separate insert to provide prismatic sections, at the expense of manufacturing cost, since the need for adequate compressive strength is an overriding requirement.

The present invention provides a design that seeks to overcome at least one of the

disadvantages of the prior art.

According to the present invention there is provided a tray, a blank for making the tray and a method of creating the tray from the blank.

The tray according to the present invention is a tray with corner reinforcements that is made from a single blank.

Preferably the corner reinforcements are self locking. Preferably they have tabs that engage into slots in the tray.

Preferably the tray has a base and four sides.

Preferably the slots are in the base of the tray.

Preferably the blank is substantially square or rectangular.

Preferably the blank is formed from a corrugated material.

Preferably the blank is formed from cardboard.

Preferably the corner reinforcements form reinforced corners with prismatic sections.

t5 Preferably the prismatic sections are each defined by three walls -i.e. they have a triangular cross-section.

Preferably the reinforced corners are capped with a stacking surface -one in each of the corners.

Preferably the corner reinforcements include a doubling of the wall thickness of the tray at the corners of the tray.

Preferably the corner reinforcements include prismatic sections.

Preferably the corner reinforcements provide a tripling of the wall thickness at the corners of the tray with respect to at least one of an end panel and a side wall side thereof.

The present invention also provides a tray comprising: a base panel; two end panels; two side panels; four corners and reinforcement sections located at each of the corners, wherein all the above components are formed from a single continuous blank, and the reinforcement sections define both a secondary wall thickness for the corners and a prismatic section for the corners, Preferably the corners are formed by the meeting of the side panels and the end panels, although chamfered corners may instead be provided.

Preferably the secondary wall thickness in each corner is provided in two parts, one part formed by a pane! that extending from one of the end paneEs and the other part formed from a panel extending from one of the side panels.

Preferably the prismatic section is formed from a panel that extends one of the end panels or one of the side pane]s, but more preferably from an edge of one of the side panels.

Preferably the corners are capped with a stacking surface -one in each of the corners, and those stacking surfaces are also formed from such a panel -preferably the same panel as the prismatic section covered thereby.

Preferably the reinforcement sections are self locking. Preferably they have tabs that engage into slots in the tray. Preferably the slots are in the base of the tray.

As stated above, the present invention aims to alleviate one or more of the probLems associates with the crent prior art. Reinforcement sections are required to enable stacking of multiple trays during storage. Although the trays themselves are often light, the contents often weighs many kilograms, and so the bottom tray in a stack of such trays. e.g. a stack of over 5 such trays, must be able to withstand a large amount of compressive force.

Existing designs already employ double thickness walls at the corner sections, eg. by means of an insert or a folding panel. The present invention, however, provides a stronger, yet simple and efficient design, and thus achieved the advantages without adding to the cost of the raw materials used to form the trays.

The present invention incorporates multiple reinforcement layers, such as double or triple layers, and a prismatic section, while still maintaining a simple and compact design, with minimal or non excessive edge-line or corner intrusion, and in a way that can be achieved from a single blank with minimum waste. -the blank is an almost complete square or rectangle of sheet material. The invention even results in a potentia][y stronger tray for the given complexity and manufacturing cost.

Throughout this specification, the term reinforcement section' or reiriforced corners is used to refer to a group of components which supplement the walls of the end and side panels of the tray, and include folded tabs or panels directly attached to those end or side panels. These components have as a primary function the adding of compressibility strength.

The majority of the compressive strength comes from the prismatic section. The prismatic section includes elongated shapes of any cross section, although triangular is the preferred arrangement. Nevertheless it could include an open-section shape.

While it is envisaged that a closed sectional shape, i.e. generally tubular, will be most effective, it is also within the scope of the language to include open sections.

Further, although it is preferred that the prismatic section has no individual capping member, with the corner cap being instead extending across the extent of the double wall reinforcement instead, closed end structures for the prismatic section elements are also able to be provided at least at a bottom end of that prismatic member.

The member or members forming the secondary wall thicknesses preferably have a surface that is located adjacent and touching the prismatic section member. Such an arrangement acts to increase the critical buckling stress of the prismatic section. It is not essential, however, for these double thickness sections to be touching the prismatic sections however.

Preferably, the tray is self locking. This requires that no additional items or manufacturing steps are required to fix the tray in its folded state, once folded, thus reducing costs.

Preferably, the tray is self locked by tabs on one panel mating with slots located on another panel, e.g. on a panel orientated perpendicularly to the tabs. This is a common method of providing a self locking design, but is particularly weH suited to the present invention for locking its various reinforcement members in their final locations. While such tabs and slots add to the complexity of the design at the initial design stage, they ultimately provide a comparatively simple and robust method of maintaining the tray in a folded configuration, and without additional later processing steps, such as applying glue or staples. Such a method of locking is also capable of being easily unlocked by an operator to enable the tray to be reverted back to a blank for compact storage or recycling when empty.

Preferably, the tray is self locked by tabs on the reinforcement sections mating with slots in the base panel. This arrangement is efficient in terms of providing a robust lock with few slot and tab pairs. This arrangement can also be additionally efficient since by locking the reinforcement sections in each corner relative to the base panel, the side and end panels are normally also locked in position.

While the most preferable arrangement is the use of slots and tabs, it is acknowledged that other known locking arrangements from the art are suitable too.

It is also possible, however, to use glue or staples either instead of or in addition to these self locking arrangements. Such glue and staples can provide a more robust or permanent assembly! which may provide advantages in certain situations. However, such permanent connections reduce the ease of disassembly, and increase the number of materials present in the tray, thus potentially making the products less easy to recycle.

Preferably, flat stacking surfaces are providedfor allowing multiple trays to be stacked on top of each other. As mentioned earlier, large numbers of identical trays will need to be stacked vertically when transporting and storing large volumes of product. As such it is helpful to enable numerous trays to stack on top of each other stably. While there are numerous ways of achieving this (e.g. a series of pins on the top of a lower tray which mate with a series of holes on the bottom of the upper tray), a series of flat stacking surfaces is preferred. Caps on the corners, plus a flat base -tabs preferably do not pas beyond the base of the tray even where they extend into slots in the base of the tray -help to provide this.

A further consideration is that it is desirable that the stacking surfaces are located to avoid significantly reducing the capacity of the tray, and also largely to maintain access to the contents therein. As such, locating these surfaces in the corners of the tray is beneficial. Stacking surfaces may however be provided within the central, storage area of the tray, or over the entirety of the tray.

Preferably, four flat stacking surfaces are provided, one in each corner of the tray above each prismatic section. Such a design has the advantages of providing ample surface for stable stacking, but minimising the amount of material used. As the stacking surfaces are located above the prismatic sections -where there can be no tray contents -the stacking surfaces do not excessively inhibit access to, or sight of, any of the contents.

Preferably, the fiat stacking surfaces are chamfered triangular sections. Preferably these triangles have a 900 corner which is located in the corner of the tray, with the hypotenuse of the triangle cutting across the corner. Such sections are less obtrusive and therefore do not inhibit access to the tray as much as say a square shape. Other configurations and shapes of stacking surface are possible though.

Preferably, each flat stacking surface is directly connected to a prismatic section and a side panel by means of a fold line. This produces a very integrated and compact design. The stacking surface is able to act as a connector between the large side and end panels and the smaller, more compact reinforcement section cornprising the prismatic section. Additionally as the prismatic section will be incorporated to increase the compressive strength of the tray for stacking, it is beneficial to have the prismatic section directly connected to the stacking surface.

Preferably, the material is cardboard. Preferably, the material is corrugated cardboard.

Cardboard provides a lightweight material which is easy to work with. Corrugated cardboard provides additional strength while still being lightweight and suited to being scored, creased, cut and folded. Other materials may be used though and may be preferred depending on the purpose of the tray. Other potential materials include plasttcs, especially corrugated plastics, and even composites or metals, although these may be less suitable for folding or producing a self locking structure.

Preferably, both side panels comprise a recess in the upper, free edge. The term recess refers to any reduction in the height of the side walls at any point along their length. Such a recess improves the visibility of and access to the contents of the tray, meaning the trays can more easily be used to display produce.

A hole or window in the side or end panels may be incorporated into the tray. While this may improve the access to, and visibihty of the contents, a hole or window will not provide useful material space within the blank which can be used for forming other components, as discussed En more detail later.

Preferably, the recess has a height of between one tenth and one half of the height of the side panel.

Preferably, the recess extends along between one quarter and four fifths of the length of the side panel.

Preferably, the recess has a substantially rectangular shape, perhaps with two rounded corners. Although a rectangular shape offers an aesthetic appearance and ease of manufacturing, the recess could arso be of other shapes.

Preferably, the reinforcement sections comprise a triangular prismatic section.

Triangular sections are preferable as they are strong, stable and robust. Further, they require less material than a square, or use it more efficiently, by only having three sides not four, and an inherent stability in that the triangulation cannot collapse until a wall buckles.

Right angled isosceles triangles are most suitable as they provide a predicable, potentially maximised, buckling strength while still being able to fit snugly within the corner of a tray due to the presence of the right angle. Nevertheless, other cross sections could be used for a reinforcement section, for example circular, square or rectangular1 all of which are within the scope of the present invention.

Preferably, two surfaces within the reinforcement section have a double thickness.

Having two surfaces of double thickness provides significantly increased compressive strength over one, and is also more stable. Additional layered surfaces may be provided within the reinforcement section within the limits of the available material. For example, in the illustrated example, one is triple thick.

According to another aspect of the present invention there is provided a single continuous blank for making a tray, the blank comprising sections to make: a base panel, two end panels, two side panels and four reinforcement sections, each reinforcement section being for locating within a respective corner of the tray, and each reinforcement section comprising a corner panel and a prismatic section, wherein the blank is adapted such that the blank can be folded to make the tray, with each prismatic section being placed by that folding next to a respective corner panel within a respective one of the four corners of the tray.

Preferably each side panel has two substantially square panels connected thereto, which, upon folding, fomi triangular stacking surfaces to allow stacking of the trays.

These square surfaces could equally be attached to the end panels of the tray. In use, these squares are orientated horizontally, at 900 to the panel to which they are attached.

Preferably the square panels not only provide a surface for a second tray to stand on, but also are used for attachment of at least part of the reinforcement section components.

Preferably, at least part of one side of each square is directly connected to a side panel by means of a fold line. This design provides a direct connection to transfer the force of the stacked box through the side wall to the floor or the stacking surface of the box below. Equally, the square section, and hence reinforcement section, could be directly connected to the end panels as opposed to the side panels. A design such as this would be substantially the same as the present invention, except for being connected to a side, and not end, panel.

Preferably, at least part of one side of each square is directly connected to at least part of one side of the prismatic section by means of a fold line. As the prismatic section will be supporting the majority of the vertical load within the reinforcement section, it is desirable for it to be directly connected to the square section which forms the stacking surface. While this is preferred, the prismatic section can be connected to a different adjacent panel, for example the end panel. A less efficient use of the space on the blank will result, however.

Preferably, at least part of one side of each square is directly connected to at least part of one side of the corner panel by means of a fold line. Thecorner panel will also be taking a portion of the vertical load and so would benefit from being connected directly to the square. As with the prismatic section, the corner panel could be connected elsewhere, but connecting it to the square assists in locking the side panel to the end panel upon assembling the tray since the corner panel will sandwich a flap of the end panel against the side panel.

Preferably that flap of the end panel extends from the side of the end panel. Preferably there is a similar flap at both sides of the end panel.

A further benefit from having both the prismatic section and corner panel directly connected to a square, which in turn, is connected to a side panel is that it results in a compact design on the blank -a design with minimal space wastage.

Preferably, the side panels comprise a recess in what is, when folded, the upper, free edge. The recess improves the ease with which the contents of the tray can be viewed and accessed. A recess also allows the contents of the tray to be viewed when trays are stacked, something that is not possible with many prior art arrangements.

Preferably, the recess has a height of between one tenth and one half of the height of the side panel. Preferably, the recess extends along between one quarter and four fifths of the length of the side panel. Preferably, the recess has a substantially rectangular cross section.

Preferably, at least one of the reinforcement sections is at least partially formed from at least part of that part of the blank that is cut from the side panel to form the recess.

Preferably at least a part of at least one of the prismatic sections is formed from that at least part of the blank.

By using material taken from the side panels to create a recess to form at least a part of the reinforcement sections, the total amount of material made available for forming the reinforcement sections is increased, thus reducing the overall amount of material needed to form the blank. Reducing the amount of material needed makes the manufacturing process more efficient.

The blank can be used to form the tray of the preceding aspects, and as such may have corresponding features for doing so.

According to a further aspect of the present invention there is provided a method of making a tray from a blank comprising providing a blank and folding the blank to form a base panel, two end panels, two side panels and reinforcement sections, wherein the reinforcement sections each comprise a corner panel and a prismatic section, the prismatic section being located within the corner of the corner panel, and both the corner panels and the prismatic sections are formed from the blank.

The reinforcement sections preferably locate into the corners of the tray during the folding process, those corners preferably being where the side panels meet the end panels. These corners and reinforcement sections increase the compressive strength of the tray. The corners are preferably right-angles, although they may instead be chamfered or rounded The corner panels may each comprise two perpendicular panels located flush against the side and end panel respectively.

The prismatic section may sits within the corner panel touching thereagairist.

The tray is produced from a single blank, which is cut from a sheet then later folded into shape. Th! blank can be folded by hand or by machine.

Preferab'y the blank is self locking in that no additional glue or staples are required to secure the folded tray in its assembled state. Preferably the self locking arrangement is provided by way of slots and tabs, e.g. slots in the base panel and tabs in at least one of the panels used for forming the reinforcement sections.

Preferably, at least one square section aftached to each side pane! is folded diagonally to form a twin-thickness triangle which lies spaced from but substantially parallel to the base panel. As such, in use it lies substantially horizontally. It can be used to support a stacking of multiple trays by providing a stacking surface onto which the base of another tray can rest.

Preferably a stacking surfaces is provided at each upper corner of the tray.

Preferably the blank is substantially square or rectangular in plan prior to folding. It will have numerous cuts and fold lines (or scores or perforations) thereon.

Preferably the section of the blank used to form the base section has eight slots, and each reinforcement section is secured in a self locking manner by way of two tabs.

Preferably one is on a part of its prismatic section and the other is on a part of its corner panel.

Preferably the corner panel is formed in two parts, a first part extending from the end panel and a second part extending from the side panel. Preferably the first part provides a further thickness for the corner panel, it extending parallel to at least a part of the second part when the tray is in the assembled configuration. In that configuration the second part is preferably folded to support two walls of its respective tray corner.

Preferably the prismatic section is formed from a further panel extending from the side panel. Preferably the further panel is scored or creased with two parallel lines to allow it easily to be folded into a triangular-sectioned shape.

Preferably the tab for the corner panel is the part thereof that extends from the side paneL.

Preferably the further panel is a substantially rectangular section attached to a side of the square section, i.e. the part which becomes the twin-thickness triangle.

Preferably the second part of the corner panel is formed from a further substantially rectangular section, attached to the other side of the square section.

Preferably the second part is scored or creased to provide a single fold line such that it can easily be folded once to form a right-angled corner panel.

Upon folding the triangular stacking surface and side panel into position, the prismatic section and corner panel are located within the tray and they can be folded to house the prismatic section within the corner panel in the corner of the tray.

A lid could be provided for the tray For example, the lid could entirely cover the contents and allow a similar tray to be stacked on top of the first.

These and other features of the present invention will now be described in further detail, purely by way of example, with reference to the accompanying drawings in which: Figure 1 is a partial perspective view of a prior ad design showing an internal reinforcement arrangement; Figure 2 is a plan view of a blank for forming the prior art design of Figure 1; Figure 3 is a partial perspective view of a tray according to the present invention showing an improved internal reinforcement arrangement and a lack of overhanging sides; Figure 4 is a plan view of a blank for forming the embodiment of Figure 3; Figure 5 is a partial perspective view of the embodiment of Figure 3 in a partially assembled state; Figure 6 is a further partiat perspective view of the embodiment of Figure 5 after some subsequent folding steps have been carried out; ELgure 7 is a further partial perspective view of the embodiment of Figure 6 after some subsequent folding steps have been carried out, but prior to self-locking the prismatic section into the corner of the tray using a tab and slot arrangement; and Figure 8 is a further view of the tray, fomied using the blank of Figure 4, in a partially assembled state -two of the four corners are fully assembled.

Referring first to Figures 1 and 2, a prior art tray 100 can comprise a base panel 110, two end panels 120 and two side panels 130. Reinforcement panels 140a, 140b, 160 are also provided in all four corners to increase the compressive strength of the tray 100.

The prior art design of Figure 1 is also a self locking design, with the end and side paneLs 120 and 130 and the reinforcement panels 140a, 140b, 160 being all locked in their respective assembled positions by mated locking means 150-see the tabs 150a and slots iSOb in Figure 2. The tabs 150a are formed on parts (edges) of the reinforcement panels 140a, 140b and the slots 150b into which they fit with a friction fit are formed in the base panel 11 Dy.

To form the reinforcement panels, both ends of the end panels 120 have a large foldable tab 160, which is folded at 900 to the end panel 120 such that when the tray is in the assembled condition it is located between the side panel 130 and further parts 140a of the reinforcement panels. These large foldable tabs 160 keep the end panels in their folded, upright (perpendicular to the base) position, as, when the tabs 150a and slots 15Db are mated together, the end panel tabs 160 are sandwiched between the side panel 130 and the further part 140a of the reinforcement panels and is prevented from rotating away from the base panel 110 by the fact that that further part is folded over that foldable tab from the edge of the side panel.

The further parts 140a, 140b of the reinforcement sections 140, 160 are foldably attached to the side panels by horizontal ledges 170, which in turn are foldably attached to the side panels. The horizontal ledges 170 are used to allow multiple trays 100 to be stacked vertically, and offer additional strength to the box.

Referring now to Figures 3 and 5 to 8 an embodiment of the present invention is illustrated in various stages between a flat blank and a fully assembled tray 200.

Figure 4 shows a plan view of a blank for forming the embodiment of Figures 2 and 5 to 8 and it shows the layout of the appropriate cuts, scores and perforations provided therein on such that the tray can be formed from a single continuous flat blank arrangement.

As can be seen in these Figures, like the prior art the tray 200 of the present invention comprises a base panel 210, two end panels 220 and two side paneLs 230. Further, in each corner is a reinforcement section 240. However, rather than just the reinforcement panels, hereinafter referred to as the corner panel 260, there is additionally a prismatic section 250.

Each side of both end panels 220 again comprise a large folding tab 270 and these folding tabs 270 and hence the end panels 220 are locked in an assembled position, flush against the side panels 130, through interaction with the reinforcement section 240 and a locking tab arrangement on the corner panel 260. However, additional securement is provided by means of a two tab and two slot arrangement 280 and 290 which involves the prismatic section as well as the corner panel. This improves both the stability of the corner's construction in that the self locking arrangement is more secure, and also it increases the compressive strength of the tray at those corners, whereby the tray has an overall improved compressive strength in relation to stackability..

The base panel 210, the end panels 220 and the side panels 230 panels are all mutually perpendicular and the reinforcement sections 240 nests in each corner (i.e. both the corner panels and the prismatic sections).

Each corner panel 260 consists of two joined perpendicular panels 260a and 260b and a third pane! 270. The third panel 270 is the large folding tab 270 discussed above.

The two joined panels 260a, 260b are attached, via panel 260a, to a section 300 of the blank. That section 300 is square when in an unfolded state, but once folded, is a twin-thickness triangle that acts as a stacking surface 300a for receiving a base of a further tray when stacked thereon.

The two joined panels 260a and 26Db of the corner panel 260 Lie in the assembled condition of the tray flush against the end panel 220 and the folding tab 270, respectively.

The prismatic section 250 is also located in the corner of the tray. It has three sides since it has a triangular section. Two of the sides 250a and 250c lie flush against the two joined panels 260b, 260a, respectively.

The third side 25Db of The prismatic section 250 cuts across the corner, here at an angle of about 45°, to bridge between the two joined panels 260a and 26Db. That side completes the triangular cross section of the prismatic section 250.

A tab 290a is located at the bottom of that third side -the side that forms the hypotenuse of the triangular cross section 25Db of the prismatic section 250. That tab 290a, mates with a slot 290b in the base panel of the tray to lock the prismatic section 250 and the corner panel, including the joined panels and the folding tab 270, together in their upright orientations relative to the base panel, i.e. generally perpendicular thereto, in the corner of the tray. This tab 290a supplements or adds to the securement provided for the corner panel by its the tab 280a.

Figures 5 to 7, and 8 -the step prior to 5 -illustrate the folding process for the corner elements for arriving at the assembled tray.

With regard to Figure 5, the side 230 and end paneLs 220 are already folded up perpendicular to the base panel 210, and the folding end tab 270 is already folded inside and flush against the side panel 230. Attached to a top edge portion at both ends of the side panels 230, above where the folding end tabs 270 are located, is the square section 300, with the further panels 250, 260 attached to its inner and outer edges. The inner edge refers to the edge parallel to but furthest away from the adjacent end panel 220 and the outer edge refers to the edge parallel to and closest to the adjacent end panel 220.

Attached to the inner edge of the square section 300 is the panel for forming the prismatic section 250. That panel is generally rectangular and is here attached thereto by its shorter side along just a short extent of the square section 300 -here about half the length of that edge of the square section 300. That panel includes the three parts that fold to form the triangular section for that prismatic section, and the attached part is the shorter end of one of those parts.

Attached to the outer edge of the square section 300 is a further rectangle -here a larger one 260, again attached by its shorter side along an edge thereof, but this time it is preferred to be along its wtiole edge rather than just a short extent thereof. The length is about half the length of the side of the rectangle. This rectangle forms the joined panels of the corner panel and has a hinge line along its long centreline.

Since the three parts of the prismatic section and the two parts of the joined panels all define a corner reinforcement for the tray, they will all finally have approximately the same height, so they should each extend from the square section by approximately the same length.

The middle part 250b of the rectangle on the inner edge of the squae section 300 and the lower part of the rectangle 260 on the outer edge of the square section 300 both are formed with one of the two tabs (290a and 280a, respectively. These tabs are located on the sides thereof that are furthest from the square section 300.

Now with reference to Figure 6, it can be seen that the hinge line between the two parts of the rectangle 260 on the outer side of the square section 300 has been folded, so the lower part 260b folds inwardly, towards the longitudinal centreline of the tray 200.

The connection between the square section 300 and the upper part 260a of the rectangle 260 has also been folded to bring the rectangle towards the longitudinal centreline of the tray 200.

The two hinge lines between the three parts 250a 250b 25Cc of the other rectangle 250 are also folded, here so that both the middle part 250b and the lowermost part 250c swing further away from the longitudinal centreline of the tray 200 than the one above it and the three parts 250a, 25Db and 250c can thus continue to be folded to form a triangular prism.

The connection between the square surface 300 and rectangle 250 has also been folded so that the three parts (250a 250b 25Cc) thereof collectively swing away from the longitudinal centreline of the tray.

The square surface 300 itself is also folded -here diagonally along a line of symmetry running from its lower inner point to its upper outer. This then forms two isosceles triangles 300a and 300b and brings the prism downwards. The fold is made so that the triangle 300b to which the three parts 250a 250b 250c, and hence now the prismatic section 250, are attached is brought down towards the longitudinal centreline.

Next from Figure 7, the final folds can be determined. The square section 300 is folded along its lower edge and this brings the entire reinforcement section 240 in towards the inside of the corner of the tray 200. As the diagonal fold in the square surface 300 completes, one triangle 300b folds under the other 300a. This brings the prismatic section 250 in to be housed along the inside of the corner of the corner panel 260, with the largest rectangle 250b facing out.

As all the folds are made, therefore, the three parts 250a 250b 250c form a triangular prismatic section 250 and the two larger parts the joined panels 260a 260b form a right angled corner panel that overlies the folding tab 270.

Finally, as can be seen from figure 3, tabs 280a and 290a mate with slots 280b and 290b respectively, to lock the reinforcement section 240, and hence the side 230 and end panels 220, in position.

Although the above description relates to a preferred embodiment, and Figure 4 shows a blank for such a tray 200, it is to be appreciated that the dimensions can be altered to make the base shape differ. For example, the tray length can be slightly shorter or much longer -the gap between panels 250 would then vary. Further, the heights of the side panels can vary with corresponding changes then being made to the lengths of the rectangles 250 and 260.

The blank can be cut, scoped or creased or perforated to help with the various folds.

For example, heavy lines in Figure 4 represent creases and lighter lines represent cuts or perforations. Regarding those perforations, the legend in Figure 4 lists 6 mm and 10mm knife/gap or knife/bend arrangements. These are also alterable to best suit the application to which the tray is to be applied. The perforations might also facilitate flattening of the box without unfolding all the panels by having the perforations there for fracture upon appropriate side forces being applied thereto. The perForations should nevertheless adequately support the tray during normal use.

The present invention has been described above purely by way of example.

Modifications in detail may be made to the invention within the scope of the claims appended hereto.

Claims (30)

1. CLAIMS: 1. A tray comprising: a base panel; two end panels; two side panels; four corners and reinforcement sections located at each of the corners, wherein all the above components are formed from a single continuous blank, and the reinforcement sections define both a secondary wall thickness for the corners and a prismatic section for the corners.
2. 2. The tray of claim 1, wherein the secondary wall thickness in each corner is provided in two parts, one part formed by a panel that extending from one of the end panels and the other part formed from a panel extending from one of the side panels.
3. 3. The tray of claim 1 or claim 2, wherein the prismatic section is formed from a panel that extends from an edge of one of the side panels.
4. 4. The tray of any one of the preceding claims, wherein the reinforcement sections are self locking.
5. 5. The tray of any one of the preceding claims, wherein the reinforcement sections have tabs that engage into slots in the tray.
6. 6. The tray of claim 5, wherein the slots are in the base panel.
7. 7. The tray of any one of the preceding claims formed from a single blank that has an unfolded shape approximating a complete square or a complete rectangle.
8. 8. The tray of any one of the preceding claims, wherein the prismatic section has an elongated shape with a cross section that is generally triangular.
9. 9. The tray of any one of the preceding claims, wherein no adhesive or staple is used to fix the folded blank in its folded, tray-forming state.
10. 10. The tray of any one of the preceding claims, wherein four flat stacking surfaces are provided, one in each corner of the tray above each prismatic section.
11. 11. The tray of claim 10, wherein the stacking surfaces are generally triangular.
12. 12. The tray of any one of the preceding claims, wherein both side panels comprise a recess in their upper, free edge.
13. 13. A single continuous blank for making a tray, the blank comprising sections to make: a base panel, two end panels, two side panels and four reinforcement sections, each reinforcement section being for locating within a respective corner of the tray, and each reinforcement section comprising a corner panel and a prismatic section, wherein the blank is adapted such that the blank can be folded to make the tray, with each prismatic section being placed by that folding next to a respective corner panel within a respective one of the four corners of the tray.
14. 14. The blank of claim 13, wherein each side panel has two substantially square panels connected thereto, which, upon folding, form triangular stacking surfaces to allow stacking of the trays.
15. 15. The blank of claim 14, wherein the square panels not only provide a surface for a second tray to stand on, but also are used for attachment of at least part of The reinforcement section components.
16. 16. The blank of any one of claims 13 to 15, wherein at least part of one side of each square is directly connected to at least part of one side of the prismatic section by means of a fold line.
17. 17. The blank of any one of claims 13 to 16, wherein at least part of one side of each square is directly connected to at least part of one side of the corner panel by means of a fold line.
18. 18. The blank of any one of claims 13 to 17, wherein flaps of the end panels, used for forming parts of the reinforcement sections extend from the sides of the end panels..
19. 19. The blank of any one of claims 13 to I 8, wherein the side panels each comprise a recess in what is, when folded, the upper, free edge and at least one of the reinforcement sections is at least partially formed from at least part of that part of the blank that is cut from the side panel to form the recess.
20. 20. The blank of any one of claims 13 to 19, adapted for forming a tray according to anyone of claims ito 12.
21. 21. A method of making a tray from a blank comprising providing a blank and folding the blank to form a base panel, two end panels, two side panels and reinforcement sections, wherein the reinforcement sections each comprise a corner panel and a prismatic section, the prismatic section being located within the corner of the corner panel, and both the corner panels and the prismatic sections are formed from the blank.
22. 22. The method of claim 21, wherein the reinforcement sections locate into the corners of the tray during the folding process, those corners being where the side panels meet the end panels.
23. 23. The method of claim 21 or claim 22, wherein the corner panels each comprise two perpendicular panels located parallel to and against the side and end panel respectively.
24. 24. The method of any one of claims 21 to 23, wherein the prismatic section sits within the corner panel touching thereagainst.
25. 25. The method of any one of claims 21 to 24, wherein the folding of the blank and the finishing of the assembly of the tray involves no additional glue or staples.
26. 26. The method of any one of claims 21 to 25, wherein the reinforcement sections are retained in their assembled positions by slots and tabs.
27. 27. The method of any one of claims 21 to 26, wherein the folding includes diagonally folding at least one square section attached to each side panel to form a twin-thickness triangle which lies spaced from but substantially parallel to the base panel.
28. 28. The method of any one of claims 21 to 27, wherein the corner panel is formed in two parts, a first part extending from the end panel and a second part extending from the side panel.
29. 29. The method of any one of claims 21 to 28, wherein the prismatic section is formed from a further panel extending from the side panel.
30. 30. A tray substantially as hereinbefore described with reference to any one of figures 3 or 5 to 8.ID

    31 A method of forming a tray substantially as hereinbefore described with reference to any one of figures 3 or 510 8, 32. A blank according to Figure 4.