A stackable carton with ventilation channels

TECHNICAL FIELD

This invention relates to a storage process.

In particular, this invention relates to a storage process which utilises packaging having particular use in the commodity business whereby large numbers of containers are required to be handled.

BACKGROUND ART

Discussion throughout the specification shall be made to use of the present invention in relation to the kiwifruit industry.

However, this should not be seen as limiting as the present invention can be used in many other industries, with various produce such as fruit and flowers, meats and processed foods such as cheese. It should be appreciated that many of the considerations that apply to kiwifruit however, are also equally applicable to other products.

The kiwifruit industry in New Zealand is very large with some 2 billion pieces of fruit being exported to 65 countries. Depending upon the market, kiwifruit is packaged in a variety of ways. A prime requirement of packaging however is that the kiwifruit arrive at its final destination in an unspoiled state. Fruit spoilage cause considerable loss of revenue for those in the industry.

Another desired characteristic of produce packaging is that it looks attractive and augments the brand value associated with the produce. Yet another requirement is that the packaging is easily disposable and preferably biodegradable.

As a solution to all of these requirements there has been developed printed cardboard boxes designed to take a significant quantity of kiwifruit, say in the order of between 30 and 140 kiwifruit depending on the kiwifruit size and the box size. These boxes are made for sufficiently rigid cardboard that they can hold their size against the weight of the kiwifruit contained therein and boxes stacked on top.

Avoiding fruit spoilage can be difficult to achieve. Kiwifruit are climacteric fruits which have a period of rapid ripening. Typically kiwifruit are picked in an unripe state, packaged and then chilled to slow down the metabolic and ripening processes.

Effective chilling of fruit can be difficult to achieve given that the sheer volume of the packaged kiwifruit means that there is a significant mass and hence specific heat to reduce down in temperature. This is compounded by desirability in the industry to use minimal floor space within coolers by stacking the cartons so the carton sides abut each other with stacks many layers high.

Typically, boxes are placed manually on top of a pallet. Pallets are generally standardised having a flat base and legs allowing four way entry by fork lift tines.

Once the pallet has been stacked with the required number of boxes, a cap in the form of treated cardboard is placed on top of the boxes and to help hold the layer of boxes in place relative to each other.

Right angled corner protectors made from rigid cardboard extend up from the top surface of the pallet to the caps to provide a rigid structure encasing the stack of boxes.

For example, with modular bulk boxes used in the kiwifruit industry, 100 boxes can be stacked (10 x 10 on a pallet) to produce a stack approximately 2 metres high, which contains around ten thousand fruit. The fruit in these boxes can take three or more days to cool down to the desired temperature. Similar problems occur when it is desired to introduce a controlled atmosphere to the fruit within a stack. For example, it may be desired to introduce ethylene to hasten the ripening process just prior to the fruit being placed in a retail outlet. A stack configuration does not allow ready access of that controlled atmosphere to the fruit in the centre of the stack, thus causing uneven ripening.

In an attempt to address this problem apertures (generally round in size and shape) were introduced in the ends of the cartons. In theory these apertures allow some horizontal flow of air through the abutting cartons.

Further, to maintain the structural integrity of the cartons the apertures are required to be small in size. Further, the natural flow of gases having a temperature differential is in the vertical direction, which this design does not readily allow.

Another problem to address is ensuring that the boxes stay in place relative to each other.

In an attempt to address this, some packaging has been made which lugs extending from the top surface of the boxes into recesses in the bottom surface of the boxes placed on top. These lugs also interact with recesses in the top cap to help secure it to the stack.

Unfortunately, this still does not provide sufficient stability to the stack of boxes.

Problems often arise during the initial phases with placing the first row of boxes onto the wooden pallet. It is very easy for the workers not to place the first layer in the correct positions. Consequently subsequent layers are also effectively out of position which can cause an unstable load, or a non uniform stack which makes it difficult to have the desired close packing between pallets.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice. All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION

According to one aspect of the present invention, there is provided a carton including

a base, and

walls extending from the edges of the base,

the carton characterised in that

at least one wall is configured to provide a fluid conduit extending from the base of the side wall to the top of the wall.

According to one aspect of the present invention, there is provided a pallet including

a support platform for placing cartons thereon,

characterised in that

the support platform includes recesses designed to cooperate with protrusions depending from the base of the cartons.

According to another aspect of the present invention, there is provided a carton including

a base

walls extending upwards from the edges of the base,

characterised in that

the carton includes protrusions depending downwards from the base and recesses positioned on an upper part of the carton wherein the recesses are designed to cooperate with the protrusions.

According to yet another aspect of the present invention there is providing a packaging system including a pallet as described above, in combination with cartons as described above.

The term fluid conduit should be understood to be any passageway that fluid (most likely a gas) can travel along. For ease of reference throughout the specification, the fluid conduit will be referred to as a ventilation channel, although it should be appreciated that the conduit can be used for a number of uses other than just purely ventilation - for example, cabling. In preferred embodiments, the carton will be of similar size and shape to that already used in industry but with the addition of the fluid conduits or ventilation channels.

For example, if a carton in accordance with the present invention was to be used in the kiwifruit industry, then it is envisaged that it would be made from a paper material such as cardboard.

Preferably, the carton is made from corrugated cardboard such as that described in the applicant's corresponding patent application number NZ571716.

It should be appreciated however that the choice of material should not be seen as limiting as the present invention can be applied to cartons made from other materials for example, plastics material.

The preferred use of the present invention is to provide effective ventilation channels when the cartons are used in a stacked configuration. Therefore the structure of the cartons is preferably such that they can be readily stacked on top of each other.

Therefore in preferred embodiments the entrance to the channel at the base of the side wall of a first carton corresponds approximately to the exit of the channel at the top of the side wall of a second carton positioned directly underneath the first carton.

This is most readily achieved if on a particular wall the entrance and exit of the channel are substantially immediately above and below each other.

In some embodiments, the conduit between the exits and entrances is in the form of a tortuous path providing a maximum length of travel of fluid passing along the conduit before exiting same. This gives maximum contact of the fluid with the box and the contents therein. In preferred embodiments however, the path between exit and entrance is substantially straight. Not only is this the simplest construction incorporating the present invention, but also one which ensures that the integrity of the cartons is maintained.

This latter point is very important when considering that the preferred use of the invention involves cartons having to support considerable weight.

It is envisaged that there may be any number of channels in the side walls of the carton depending upon the intended use of the carton. Consideration however must be given to maintaining structural integrity of the carton.

In preferred embodiments, the channels are in the form of well defined indents having dimensions of 20 mm wide and 10 mm deep. As in preferred embodiments the cardboard is 10 mm thick.

For reasons of strength and aesthetics, the cross section of these channels may be similar to that of the lugs/recesses which typically extend upwards from kiwifruit cartons.

In this embodiment, it is envisaged that the channel may be formed by merely stamping out or removing by other means a rectangular strip from the carton blank prior to assembly.

In similar embodiments, the channels may be formed as a consequence of projections extending from the sideways from the carton.

It should be appreciated that in normal stacking configurations, the side walls of the carton abut closely to each other. If there are projections which extend side ways out from the side walls (or base or top), then when boxes are placed close together, the projections would cause a gap between the main body of the cartons. This in effect can provide a ventilation channel between cartons. It is envisaged that this form of the invention could be achieved by having an overhang of for example, approximately 2mm from the top, bottom and/or end of the carton.

The protrusion can be achieved by a variety of ways. In one embodiment, the protrusion may result from attaching an additional piece of material to part of the carton.

In another embodiment, the protrusion may result from the design of the carton blank and the way that it is folded. In one particular embodiment, the folding of the carton blank may also enable keying in of the top surface of the carton to the side walls in the form of a locking flap, obviating the need to glue the cartons.

It is envisaged that the channels will be symmetrically positioned on the carton. This is not only for aesthetics, but also to maximise the channel size.

For example, with symmetrically positioned channels, the boxes may be placed together so that the protrusions and/or channels on each carton oppose each other, thereby effectively creating a ventilation channel having double the width of that provided by a single carton abutting a side panel without protrusions or channels.

Care needs to be taken that the gap provided by the channels does not significantly increase the floor/pallet space taken up by the cartons. Therefore, in some embodiments, it may be that the cartons have higher side panels than conventional cartons to provide the extra volume required for the same floor space. For example, to allow for the channels, the base of each carton may have a reduced cross-sectional area available to the produce requiring a greater carton height to provide the same volume. In preferred embodiments of the present invention, the cartons are made in accordance with an interlocking system. For example, the cartons may have lugs depending downwards or extending upwards from the cartons which fit into complementary indents on the cartons above and below. This system can ensure that the ventilation channels are aligned allowing maximum airflow through the carton stack.

In preferred embodiments, the present invention is used in combination with a pallet which likewise has apertures that can correspond to the positioning of ventilation channels of the cartons placed on top of the pallet.

This process is aided if the pallet has locating means that the cartons can lock into. For example, the pallet may have apertures configured so that downwardly depending lugs in the cartons can fit into them. Once the cartons are positioned on the pallet in this way, then there can be a continuous flow through of air from underneath the pallet and up through the cartons.

With protrusions depending downwards from the carton, the protrusions effectively will be acting as feet to the cartons, when the cartons are placed on a non- recessed surface. This situation is most likely to occur in a retail situation where a single layer of boxes will be used for display purposes.

It should be appreciated that the cartons would only be used in a stacked format when the lower layer of cartons have recesses that can receive the protrusions. This is because to take the full weight of the stack, the base of the box is also required to provide that support.

In some embodiments of the present invention, there will still be protrusions extending upwards from the cartons which can engage with recesses in the base of cartons stacked on top. It is thought by having lugs extending upwards and depending downwards from the cartons, that torsional stresses on the sides of the carton could be reduced when interlocked.

Another reason to have the upward projections is to enable the top layer of stacked cartons to cooperate with recesses in a cap which is preferably used with a packaging system in accordance with the present invention.

It is also envisaged that the packaging system would use corner protectors which will extend from the pallet base to the cap.

In preferred embodiments the corner protectors are made in accordance with the process as described in New Zealand Patent Application No. 569462 as this process provides an extremely strong component.

Also, in preferred embodiments the cap, the box and corner boards are made from a corrugated paper board such as that described in New Zealand Patent Application No. 571716. Again, this is preferred as this provides an extremely strong product, but should not be seen as limiting.

It should be appreciated that one aspect of the present invention includes the use of downwardly depending lugs, but without the ventilation channels. This configuration is still useful in providing a secure and stable stack for products which do not require as much ventilation as say the kiwifruit industry. For example, ventilation channels will not necessarily be required to the same degree for produce such as apples or non-organic products.

In one embodiment of the present invention there is provided a carton with at least one upwardly extending lug having at least one recess configured such that a portion of a lid of the carton can be secured therein. Such a feature enables a lid to be secured without the need for additional securing means such as tape and the like. Further, no excessive folding will be required as merely a recess is used. Further, the dual use of lugs as a source of stability and securing for the lid makes for efficient and effective design.

According to one aspect of the present invention there is provided a carton having at least one lug upwardly extending from the end of the carton wherein the carton also includes a complimentary recess to receive a lug from a similar carton placed thereunder.

This configuration gives considerable stability - particularly if the lug is comparatively large with respect to the end wall.

While reference throughout the specification has been made mainly to the use of the present invention with regard to the kiwifruit industry, it should be appreciated that the invention can apply to other packaged goods.

For example, the present invention may apply to fruit having a smaller size than kiwifruit, for example grapes and blueberries or, the present invention could be applied to products having an amorphous shape, such as cooling cheese, powder and the like.

With these particular products, it is possible that the product could be prone to fall, or ooze out of the larger apertures or channels required to gain the appropriate cooling.

According to another aspect of the present invention there is provided a carton having a number of apertures therein, the carton also including a gas permeable laminate covering said apertures.

According to a further aspect of the present invention there is provided a carton as previously described characterised in that

the carton includes a gas permeable laminate positioned over at least one of the fluid conduits provided by the carton.

In preferred embodiments, the laminate has the properties of being able to retain the products within the carton, while allowing the passage of fluid (most likely gas) into and out of the carton.

In some embodiments the laminate may be made from a gas permeable membrane having no readily visible apertures therein, such as that used in the meat packaging industry. This membrane may in some embodiments be selective, for example permitting a one way passage of oxygen and/or ethylene.

However, it is envisaged that to obtain the gas flow required, the membrane is more likely to be the form of a mesh with open apertures. The size of the apertures in likely to be such that the product within the carton will be retained without passing through the mesh and out the carton apertures.

It is envisaged that the present invention could be used in concert with corrugated cardboard such as that described in the applicant's corresponding New Zealand Patent Application No. 571716.

For example, a standard carton blank may be made having the various apertures and channels punched therefrom. The carton blank can then be conveyed to a laminating station where the laminate is adhered onto the cardboard.

The final shape of the carton blank and laminate can then be cut from the cardboard, prior to the carton being assembled from the carton blank.

The present invention has a number of advantages over the prior art. Firstly, there is provided an easy means by which large volumes of produce (and other products) can be readily cooled by the provision of ventilation channels.

Likewise, there is provided a means by which a gas can be readily delivered (or removed) from the produce as required - for example ethylene.

Further, it can be seen that an aspect of the present invention provides a simple but elegant solution to the problem of stack stability.

By having recesses on a pallet that can interact with carton lugs, the initial layer of cartons will be located exactly the right positions on the pallet. As subsequent layers have to lock into the layers below, then the whole stack of pallets will be perfectly aligned and centralised with the pallet underneath.

With embodiments that have upwardly extending lugs as well, the top cap to the carton stack will also be secured.

It can be seen that a top cap, corner protectors and interlocking pallet with the cartons can form a very rigid structure.

Further, if the components are made with corrugated paper board made in accordance with the applicants proprietary processes, there is provided a strong lightweight packaging system which is also ecologically friendly.

The present invention can be formed using simple technology such as that already developed by the applicant.

The choice of using interlocking pallet, cartons and top cap to provide aligned ventilation channels provides a secure packaging system, as a combination of features provides additional strength limiting product destruction due to crushing. BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a carton in accordance with one embodiment of the present invention, and

Figure 2 illustrates the interaction of the carton in accordance with a pallet made in accordance with an embodiment of the present invention, and

Figure 3 illustrates a packaging system in accordance with one embodiment of the present invention, and

Figure 4 illustrates virtual conduits in accordance with one aspect of the present invention, and

Figure 5 illustrates an alternative carton in accordance with one aspect of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION

Figure 1 illustrates a carton generally indicated by arrow (1) made in accordance with one embodiment of the present invention.

The carton (1) is made from a high strength corrugated paperboard such as that described in New Zealand Patent Application No. 571716.

The carton (1) has end panels (2 and 3) extending upwards from a base (not clearly shown). Side panels (4 and 5) also extend upwards from the base. In the embodiment shown, top edges (6 and 7) fold over from the side panels (4 and 5 respectively) and interlock with the end panels (2 and 3) to form a rigid box shaped structure.

In the embodiment illustrated in Figure 1 , there are a number of downwardly depending lugs (8) from the side panels (4 and 5). It should be appreciated that the lugs may depend from the ends (2 and 3) in addition to or instead of depending from the sides (4 and 5).

In this embodiment, the lugs (8) are situated close to the four outer corners of the carton to effectively act as supporting feet when placed on a flat surface.

Directly above lugs (8) are recesses (9) which are of a complementary size and shape to the lugs (8). Thus, when a carton is placed on top of another carton (as illustrated in Figure 3) the lugs (8) fit snugly into the recesses (9). In this position, the base of the carton (1) is also supported by the top edges (6 and 7).

Extending upwardly from the side panels (3 and 4) are lugs (10) having similar configurations to the lugs (8). Likewise, directly beneath the lugs (10) are recesses (11) having similar configurations to the recesses (9). Thus, the lugs (10) cooperate with the recesses (11) when the cartons (1) are stacked on top of each other.

Ventilation channels in the form of cut-outs (20) have been formed in the sides (4 and 5) of the carton (1). The channels (20) are merely rectangular slots which have been cut in between the lugs and recesses on the sides (4 and 5) of the carton (1).

An alternate form of ventilation channel generally indicated by arrow (21) is formed at the ends (2 and 3) of the carton (1). It can be seen at the ends (2 and 3) of the carton (1) that there are apertures (22) which are in a form found in typical produce cartons. Extending outwards at the top of the end panels (2 and 3) are protrusions (24). The protrusions (24) extend only in the order of around 2 mm out from the flat surface of the ends (2 and 3).

Thus it can be seen that when the cartons (1) abut each other, a 4 mm gap is formed between the side panels (2 and 3) as a consequence of the protrusions (24). This ventilation channel (21) allows air flowing between the cartons to also enter the apertures (22).

When the panels (3 and 4) abut each other, then there is provided an 4 mm wide channel which allows vertical and horizontal air flow.

It is envisaged that all of the lugs, channels, apertures and recesses shown in the carton (1) will be stamped from a flat piece of corrugated paper board. This could be stamped or rotary cut instead.

Figure 2 illustrates a pallet made in accordance with one embodiment of the present invention. The image is transparent to aid the explanation.

The pallet (12) has a number of recesses (13) that cooperate with the lugs (8) on the carton (1).

It can be seen that when the carton (1) is placed on the pallet (12), the base (14) of the carton (1) sits flat on the upper surface (15) of the pallet (12). Therefore, the full weight of the stack of pallets in not on the lugs (8) but is borne by the upper edges (6 and 7), side panels (2 and 3) and the base (14) and the pallet surface (15).

The pallet (12) also has a number of larger apertures (25) which correspond to the ventilation channels (20) on the cartons (1) when the cartons are placed in position. In some embodiments (although not shown), there may also be provided equivalent slots that correspond with the ventilation channel (21) formed by the protrusions (24).

Figure 3 illustrates a packaging system in accordance with one embodiment of the present invention. The packaging system consists of a pallet generally indicated by arrow (12) having nine feet (16) allowing a four way entry system for forklifts. Cartons generally indicated by arrow (1) are stacked so that the respective lugs (8 and 10) interact respectively with recesses (9 and 11) to form an overall locking structure.

A top cap (17) is placed on the top of the stack of cartons (1). The top cap (17) is also made from corrugated paperboard as previously described and has a number of recesses (not clearly shown) punched out therefrom, which correspond to the lugs (10) on the cartons (1).

Also not clearly shown are apertures which correspond to the ventilation channels (20) between the cartons (1) and the apertures (25) in the pallet (12).

Corner pieces (18) also made from corrugated paperboard extend from the base or the pallet (12) to the top cap (17). It can be seen that in total the structure illustrated by the packaging system is very robust given that it interlocks in multiple directions.

To further assist the integrity of the packaging system, straps (not shown) may be wrapped around the corner protectors and/or pallet and top cap to hold the whole structure into position.

Figure 4 illustrates some fluid conduits (22) that occur between stacked cartons (1). Figure 5 illustrates an alternate aspect of the present invention with a carton (30) which could be useful for produce such as apples.

The carton (30) is made from the same material as the carton (1), namely high strength corrugated paper board such as that described in New Zealand Patent Application No. 571716.

The carton (30) has a different lug configuration to that in carton (1). Namely, there is provided large lugs (31) and (32) which extend upwardly from the end walls (33) and (34) respectively of the carton (30).

Opposing the lugs (31) and (32) are recesses (35) (one recess not clearly shown). Thus, when cartons of the configuration shown are stacked on top of each other the lug (32) fits into the recess (35) providing stability to the stack of cartons.

The lugs (31) and (32) have recesses (36) formed by an undercut. The configuration recesses (36) allow a portion of the lid (37) and (38) of the carton (30) to tuck therein. Thus, the lugs (31) and (32) can act to secure the lid portions (37) and (38) of the carton (30). This obviates the need for additional tape, glue or securing means. This also enables the carton (30) to be readily opened when required.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope of the appended claims.