BACKGROUND ART Shipping or transportation containers which are used to transport tempera- ture sensitive products are normally equipped with some form of temperature regulation system. Invariably these systems are implemented through a re- frigeration or air conditioning unit which is adapted to supply and circulate temperature controlled and potentially humidity controlled air throughout the interior of the container. Normally the air conditioning unit employed is lo- cated at one end of the container with appropriate inlet and outlet ducting to extract air from the interior of the container, to condition this air and then supply it back into the container to re-circulate.

Air circulation patterns must be considered when products are loaded into such refrigerated or temperature controlled containers. Normally a"T"floor is used to distribute conditioned air throughout the interior of the container. The "T"floor consists of a series of T section extrusions which are laid along the length of the container floor with small lateral gaps between each section.

Conditioned air is supplied under the floor at one end and allowed to disburse through these lateral gaps as the air travels to the opposite end of the con- tainer.

However, T floors do not effectively distribute conditioned air throughout the entire volume or length of the container. The pressure of the supplied air de- creases further from the outlet port the air travels, so-less conditioned air reaches the opposite end of the container. This can result in one end of the container being ineffectively cooled or heated and the opposite heat effect being over cooled or heated.

One attempt to address this problem has been through increasing the power or flow rate of the air conditioning unit employed in attempt to drive more air down to the opposite end of the container. However, this also causes prob- lems with respect to the contents of the container as the material placed closest to the air conditioning element can be badly chilled and dried out and therefore subsequently damaged through the excessive amount of condi- tioned air it is exposed to.

Furthermore, T floor based container cooling systems have very little effect on the temperature of the walls of the container. In some instances products may be placed up hard against the walls of a container, leading to a degree of heat transference to these products through the container walls. In addi- tion, with tightly packed containers the products placed in contact or close proximity to the walls have limited exposure to the air supplied through the "T"floor. Very little of this conditioned air will actually reach products placed near the walls of the container, again limiting the effectiveness of the tem- perature control system employed.

One system developed to address these problems is discussed in US Patent No. US 583,057. This document describes the use of a custom built refriger- ated container which has a cooling system adapted to cool the side walls of

the container. Conditioned air is provided through supply ducts and vertical air channels formed within the interior of the container's side walls. The air supplied into the interior of the walls flows down through same and eventually will be emitted into the"T"floor of the container. A series of transverse holes are drilled through each of the T shaped forms making up the floor, thereby allowing conditioned air to travel across the width of the floor to cool the cen- tre of the container. A return duct for the conditioned air is also provided in the ceiling or roof of the container to re-circulate it back to the cooling sys- tem.

Although this implementation of a container cooling system goes someway to alleviating the problems discussed above, its design leads to further compli- cations.

The provision of air channels in the interior of the container side walls sub- stantially complicates the design and manufacturing processes which need to be executed to make the container. In effect a customised or dedicated con- tainer needs to be manufactured at substantial cost.

Furthermore, as each of these vertical air channels are provided in the inte- rior of the side walls, they cannot be easily accessed or viewed during regu- lar maintenance or inspection of the container. Any particles, contaminants or other materials carried into these channels with the air flow involved may be- come lodged or build up in layers over time, and cannot easily be removed.

This design of the container walls with integrated central channels also poses inspection problems for regulator bodies. In the case where a regulatory body needs to inspect the container for hygiene or food safety reasons, an

inspector cannot easily nor quickly determine whether the side wall ducts in effect are satisfactorily clean.

An improved temperature control apparatus for a container which addressed any or all of the above issues would be of advantage. A temperature control apparatus which could evenly and consistently distribute conditioned air throughout the entire area of a container and which also effectively cooled the side walls of the container would be of advantage. A temperature control apparatus which also'allowed all channels, cavities or ducts employed to carry conditioned air to be easily and quickly inspected and would also be of advantage.

All references, including any patents or patent applications cited in this speci- fication 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 ac- curacy 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 any country.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become appar- ent 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 tempera- ture control apparatus for a container, said container including a plurality of side walls where at least one of said side walls is formed with a plurality of channels, the temperature control apparatus including, at least one air conditioning element, and at least one removable cover element adapted to close an open face of at least one channel formed within a container side wall, wherein the apparatus is adapted to supply conditioned air to channels formed in at least one container side wall, where said at least one removable cover guides air entering a side wall channel to travel up or down the side wall.

According to another aspect of the present invention there is provided a tem- perature control apparatus substantially as described above which includes at least one air supply duct adapted to transport conditioned air from an air conditioning element to at least one channel formed with a side wall of the container.

According to a further aspect of the present invention there is provided a temperature control apparatus substantially as described above wherein said

at least one air supply duct is adapted to move with respect to the container to place a said duct in an in-use configuration or an inspection configuration.

According to yet another aspect of the present invention there is provided a temperature control apparatus substantially as described above wherein said at least one air supply duct is adapted to pivot with respect to the container.

According to a further aspect of the present invention there is provided a temperature control apparatus substantially as described above wherein the apparatus also includes the container.

The present invention is adapted to provide a temperature control apparatus.

This apparatus may control the temperature and also preferably other condi- tions of air within a region or enclosure.

In a further preferred embodiment the present invention may be adapted to provide a temperature control apparatus for a transportation or shipping con- tainer. These types of containers allow large volumes of products or other materials to be stored securely and transported long distances easily. In some instances it is also preferable to regulate the temperature of the con- tents of the container and as such a temperature control apparatus is re- quired. Furthermore, for a number of types of products to be transported within such containers it is also preferable to control the relative humidity in- side the container-such as for example when food products are to be trans- ported.

Preferably a container which the present invention is adapted to be used with may include a plurality of side walls, a floor and a roof or ceiling. In a further

preferred embodiment the container may be substantially rectangular in shape and include two side walls, a roof, floor, rear wall and front wall where this front wall also doubles as a door or entrance into the interior of the con- tainer.

Reference throughout this specification will also be made to a container em- ployed in conjunction with the present invention including two side walls only adjacent to a set of rear and front walls. However, those skilled in the art should also appreciate that the specific arrangement of walls in such a con- tainer may vary in other instances, and reference to the above only through- out this specification should in no way be seen as limiting.

Preferably each of the side walls of a container may be formed with or adapted to define a plurality of channels. These channels may run vertically, horizontally or be angled or curved along the interior face of a side wall to provide a gas flow path across the inner surface of the side wall. These channels can be formed from a depression, indentation or trough in the inner surface of the wall which presents an open face for the channel across its length along the wall.

In a further preferred embodiment a channel formed in a side wall may be formed by corrugations in the side wall. These corrugations can normally provide strength improvements to the walls of the container, and also in con- junction with the present invention, may also be adapted to provide the chan- nels discussed above.

In some instances the profile, depth or diameter of these channels may also vary depending on where on a side wall the channel is located. For example, in some instances the width or cross-section area of the channel may be re-

duced to maintain air pressure at locations on a side wall at the opposite end of the container to an air conditioning element. By reducing the cross-section area or diameter of such channels, potentially the air pressure within same may be maintained to ensure even consistent air flows across an entire side wall.

Preferably a temperature control apparatus formed in accordance with the present invention includes at least one air conditioning element. An air condi- tioning element may be adapted to heat or cool air to be circulated within a container. Furthermore, in some instances such an air conditioning element may also be adapted to control the relative humidity or moisture content of the air which it is used to condition.

Preferably an air conditioning element used in conjunction with the present invention may be positioned or located substantially adjacent to the front end or opposite the end door of a container. This will place the air conditioning element in a secure position out of the way of any cargo to be stored in the container.

Reference throughout this specification will also be made to the present in- vention including a single air conditioning element only which is adapted to primarily cool air to be circulated through a container to refrigerate or freeze its contents. However, those skilled in the art should appreciate that other configurations and numbers of air conditioning elements may also be em- ployed in conjunction with the present invention. Reference to the use of a refrigeration unit as an air conditioning element throughout this specification should in no way be seen as limiting.

In a preferred embodiment the present invention may also incorporate or in- clude at least one air flow drive system. Such a drive system may be adapted to push or suck conditioned air from an outlet or outlets of the refrigeration unit employed, and provide the motor power used to drive and circulate this air through the interior of the container.

Reference throughout this specification will also be made to the present in- vention including a single drive fan associated with an outlet of the refrigera- tion unit as an air flow drive system. However, those skilled in the art should appreciate that other configurations of air flow drive systems are envisioned and reference to the above only throughout this specification should in no way be seen as limiting.

In a preferred embodiment the present invention may include at least one air supply duct. An air supply duct can be adapted to transport conditioned air from a refrigeration unit to at least one channel formed in a side wall of the container. In a further preferred embodiment the present invention may in- clude a pair of air supply ducts with each of these ducts being used to supply conditioned air to the channels present in the pair of side walls of the con- tainer.

In a preferred embodiment the air supply duct can be positioned or config- ured so as to supply air to the upper ends or starting points of the channels formed within a side wall. This will allow air from a supply duct to be intro- duced into side wall channels in the upper regions of the wall, preferably to allow this air to flow down the surface of the side wall.

Preferably an air supply duct may be mounted in the interior of a container at the junction of the container side wall and its roof or ceiling. The duct may

then transport cooled air along the entire length of the container past the top sections of the side wall.

However, in other embodiments an air supply duct may not be configured to extend across the length of a side wall adjacent to the container roof. For example, in some instances the particular shape of the channels employed may actually function to also distribute the conditioned air involved laterally across and also down the face of a side wall. In such instances an air supply duct simply provides a passage or a path a short distance from an outlet of a refrigeration unit to one or more ends of side wall channels in proximity to the refrigeration unit.

Reference throughout this specification will however be made to air supply ducts being configured to run the length of the container and being positioned adjacent to the top of a side wall and the roof of the container. However, those skilled in the art should appreciate that other configurations of the pre- sent invention are envisioned and reference to the above only throughout this specification should in no way be seen as limiting.

In a preferred embodiment an air supply duct may be adapted to move with respect to the container which it is associated with. In such an embodiment the air supply duct may preferably be moved between two particular configu- rations or positions, defined as an in use configuration and an inspection con- figuration. When placed in an in use configuration the supply duct may en- gage with a side wall to provide an air delivery path to the channels of the side wall from the refrigeration unit. Conversely, when placed in an inspection configuration the supply duct may be moved away from a side wall or roof of a container to allow visual inspection of the interior surfaces of the duct. Fur-

thermore, when placed in this configuration the interior surfaces of the air supply duct may also be cleaned easily and quickly.

In a further preferred embodiment the air supply ducts employed may be piv- otably connected to or associated with the container. In such an embodiment an air supply duct can be pivoted into engagement with the side wall and roof of a container to effectively channel refrigerated air to the channels in each of the container's side wall channels when placed in an in use configuration.

Alternatively, such a supply duct may also be pivoted away from a side wall to place the duct in an inspection configuration and thereby allow the interior surfaces of the duct to be visually inspected and also cleaned. In such em- bodiments the air supply duct involved may be pivotably connected to either a ceiling or side wall of the interior of the container to allow the supply duct to be pivoted with respect to the container.

In a preferred embodiment an air supply duct may be tapered or have a re- ducing diameter along its length as it extends away from the refrigeration unit. As such a duct is preferably adapted to supply cooled air to a plurality of side wall channels, the air pressure of this conditioned air will normally re- duce the further the air involved that travels from the air conditioning unit and drive system. However, by reducing the diameter or width of the supply duct the pressure and speed of the air may be maintained, thereby allowing condi- tioned or cooled air to be supplied in equal volumes across the entire length of the side wall.

Preferably the present invention also includes at least one removable cover element. Such a cover element or elements is adapted to close an open face of at least one channel formed on a side wall of the container. A cover can be employed to effectively seat the length of a side wall channel so that prefera-

bly cooled air can only enter a channel in the upper regions of the side wall and exit the channel at the bottom or lower regions of the side wall.

This configuration of the present invention allows a cover to be used to guide conditioned air on the surface of a side wall to cool or heat same, and also any products or the contents of the container placed in close proximity to the side wall.

In some embodiments of the present invention a cover element may be formed from a substantially transparent material. The use of a transparent material may allow visual inspection of the side wall channels without neces- sarily needing the cover to be removed from a side wall.

In a further preferred embodiment the present invention may include two re- movable cover elements only with a single cover element being provided for each side wall of the container. A single removable cover may be provided to effectively close the open faces of the side wall channels and therefore allow the channels to carry cooled air down substantially the entire surface and height of a side wall.

In a further preferred embodiment a removable cover may be formed from a sheet of film or other form of flexible fabric or material. Such a flexible film may be hung, attached or otherwise positioned in place across the entire face of a side wall to in turn close the open faces of each of the side wall channels. Such flexible sheets may be attached in the correct position in any number of ways using for example, hooks, Velcro patches, other forms of mechanical connectors or adhesive applied to either the film itself or the in- ternal surface of a side wall.

In a further preferred embodiment a removable cover element may be pro- vided through a sheet of flexible plastic film which has one side or face coated with a relatively weak chemical adhesive. This type of plastic film can easily be run out across the interior surface of a side wall with the adhesive layer employed securing the sheet of plastic film in place. Furthermore, as a relatively weak adhesive is used in such an application, the plastic sheet may also be easily peeled or pulled off the side wall and discarded when the side wall channels are to be inspected or cleaned.

In a further preferred embodiment a cover element may be formed from poly- thene film which is approximately one hundred microns thick.

Furthermore, a layer of acrylic or rubber based adhesive may be applied in a layer to one side or face of such a sheet of film to allow it to be attached to a side wall of a container.

However, those skilled in the art should appreciate that other types and thicknesses of film and further other types of adhesive or connection system may also be employed in conjunction with the present invention and refer- ence to the above only throughout this specification should in no way be seen as limiting.

Preferably the covered channels formed in each of the side walls are adapted to provide an air flow path up or down the interior surface of a side wall.

However, the path provided need not necessarily be directly a straight line, nor substantially vertical in orientation.

For example, in some preferred embodiments the channels provided in the side wall may be substantially vertical and extended across the entire height of the container side wall. However, in alternative embodiments these chan- nels may also be angled to provide some sideways or lateral travel for the air channelled. Yet in other embodiments a combination of substantially verti- cally and horizontally orientated channels may be provided in a single side wall which can guide the conditioned air involved both laterally across the face of the side wall and also down the face of the side wall.

In a preferred embodiment the container employed may also have a plurality of transverse channels formed in its floor which are linked to or in communi- cation with the lower regions of side wall channels. These floor channels can provide an air flow path between opposite side walls to carry cooled air into the central or mid-sections of the container. The contents of the container may be stacked or positioned on top of these channels with each channel having an open face or outlet slot allowing cooled air to diffuse up into the interior of the container from its floor.

Such transverse floor channels may have any number of different types of cross section profiles or configurations. Simple corrugated channels may be employed in the floor of a container in some embodiments, whereas in alter- native embodiments substantially sinusoidal wave like channels or indenta- tions may be formed in the floor of the container, extending between the side walls of same. Those skilled in the art should appreciate that any number of different types of forms or shapes of transverse floor channels may be em- ployed in conjunction with the present invention, and reference to the above only throughout this specification should in no way be seen as limiting.

In a preferred embodiment a plurality of transverse channels may be formed in a container floor through the provision of an insert sheet of material with the transverse channels required pre-formed in same. Such sheets of mate- rial may be constructed from relatively inexpensive material, such as alumin- ium or steel and also manufactured easily using roll-forming technology.

In a preferred embodiment the container employed may also include at least one return duct which is adapted to return air in the interior of the container for supply to the refrigeration unit. Preferably such a return duct or ducts may be positioned or located on the ceiling of the container and thereby can be used to collect warmed air to be cooled and re-circulated by the refrigeration unit.

In a further preferred embodiment the container involved may include a sin- gle return duct only which includes a plurality of inlet ports located along its length. Such a single return duct may be attached to the ceiling of the con- tainer and may run substantially along the length of the container parallel to each of the side walls. This placement of a return duct can employ convec- tion currents to assist in the collection of warmed air to be cooled and re- circulated.

The present invention provides many potential advantages over the prior art.

This configuration of the present invention allows conditioned air to be evenly and also efficiently circulated throughout the entire length of a container. A significant cooling effect can be applied to the side wails of the container, thereby in turn providing a cooling effect to the products or contents of the container nearest to the side walls. Cooled air can then travel down to the bottom of the side walls and then across the floor of the container where it

will slowly diffuse out into the interior of the container as it heads towards the centre of same. As this cooled air slowly heats the interior of the container can then be recycled back to the air conditioning element through the ceiling mounted return duct, which has a plurality of inlet ports located along its length to extract air from the entire length of the container.

The provision of a moveable cover element also allows the side wall chan- nels of the container to be easily inspected and also cleaned if required.

Preferably when a sheet of adhesive covered film is employed as a remov- able cover the sheet can easily be peeled off an interior side wall to gain ac- cess to the side wall channels involved.

BRIEF DESCRIFTION OF DRAWINGS Further aspects of the present invention will become apparent from the fol- lowing description which is given by way of example only and with reference to the accompanying drawings in which: Figures 1 a and 1 b show perspective and enlarged views of a container with a temperature control apparatus installed as formed in accordance with the preferred embodiment of the present invention, and Figure 2 shows an additional perspective view of the container and apparatus shown and discussed with respect to figure 1, and Figure 3 shows a perspective side cross-section view illustrating air flow paths through the container as discussed with respect to figures 1 and 2, and

Figures 4a and 4b show perspective, enlarged and cross-section views of a container with a temperature control apparatus installed formed in accor- dance with a further embodiment of the present invention, and Figures 5 and 6 shows perspective and enlarged views of a container and associated temperature control apparatus formed in accordance 5 with the further embodiments of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION Figures 1 a and 1 b show a container 1 which has elements of a temperature control apparatus installed as configured in accordance with a preferred em- bodiment of the present invention. The container 1 includes a roof or ceiling 2, floor 3, two side walls 4, rear wall (not shown) and an open front normally closed by a front wall formed as a door.

The interior surface of the side walls 4 defined as a series of channels 5 which run from the top to the bottom of the wall, and also along the entire length of the side walls 4. The-floor 3 also defines or forms a series of trans- verse channels 6 which run from each side wall across the width of the con- tainer 1.

Adjacent to the end wall of the container is provided a refrigeration unit (not shown) as an air conditioning element for the temperature control apparatus provided. The refrigeration unit is adapted to supply refrigerated or cooled air to a pair of air supply ducts 7. These ducts 7 run the length of the container and are used to distribute cooled or refrigerated to the top portions of each side wall channel 5.

The temperature control apparatus installed also includes a set of removable cover elements 9 as shown with respect to figure 1 b. Figure 1 a illustrates a side wall of a container 1 as yet uncovered by the cover 9 shown with respect to figure 1 b. The covers 9 provided for each side wall are adapted to close off the open face of each channel in the side walls thereby providing an air flow path or guide for cool air to flow down from the supply ducts 7, across the face of the side wall 4 and out through each of the lower outlets 10 of each channel 5.

The outlets 10 from each side wall channel then feed the cold air delivered into each of the floor channels 6 so that this cooled air is distributed across the width of the container.

Figure 2 also shows a more detailed view of the roof or ceiling sections 2 of the container as discussed with respect to figure 1 a and 1 b. Also shown with respect to figure 2 is a return duct 11 in the ceiling of the container 1. This duct 11 runs substantially an entire length of the container and includes a plurality of inlet ports 12 which are adapted to draw air into the duct 11, which in turn is connected to an inlet for the refrigeration unit at the rear of the con- tainer.

The design and construction of the temperature control apparatus formed allows a substantially even and efficient flow of cooled air throughout the en- tire volume of the container. This is shown more clearly with respect to figure 3 with a number of air flow arrows displayed. Cooled air is initially transported along each of the supplied ducts 7 and down the side walls of the container and through onto the bottom channels 6 of the floor. At this stage cooled air then refrigerates the contents of the container, thereby becoming heated and rising towards the inlet ports of the return duct 11.

In the embodiment discussed with respect to figures 1 through 3 the remov- able cover 9 employed is provided through a sheet of plastic material with a layer of adhesive applied to the side of the sheet to be placed into contact with the side wall of the container. The adhesive can hold this sheet of mate- rial in place to cover the open faces of the side wall channels, and therefore provide guiding conduits for cooled air down the interior faces of the side walls.

Furthermore, the supply ducts are provided with a pivoting connection 13 to the ceiling of the container. This pivoting connection 13 allow the supply ducts 7 to be pivoted away from the side wall 4 and thereby inspected or cleaned easily. The duct 7 is shown an in use configuration or position with respect to figures 1 through 3, and can also be pivoted away from the side wall and placed in an inspection configuration if required.

These features of the temperature control apparatus allow the cover ele- ments and supply ducts to be removed completely or moved out of the way to allow a visual inspection of all surfaces of the container. Furthermore, these surfaces can also be cleaned easily if required, for hygiene or food safety reasons.

Figures 4a and 4b show a container and associated temperature control ap- paratus as configured in an alternative embodiment to that discussed with respect to figures 1 and 3. In the embodiments shown the air supply duct running along the length of the side wall has been replaced through further channels formed in the inner surface of the side wall. The inner surface of the side wall has a series of vertical 5a and horizontal 5b channels formed to carry cool air along the length of the container and also down the side walls.

An air supply duct may still be provided to supply refrigerated air to the upper most horizontal channels provided in each side wall. Figure 4b also illustrates how a single cover element may be used to cover the entire surface of the side wall, thereby controlling or guiding the passage of cooled air down the wall.

Figures 5 and 6 show yet further embodiments of the present invention, again with different versions or shapes of channels applied to the interior sur- faces of each of the side walls of the container. In the embodiment shown with respect to figure 5 a series of sets of vertical and horizontal channels are applied along the length of a side wall, whereas a series of angled channels are applied to the side wall as shown with respect to figure 6. Again in both these embodiments the angled channels or horizontally orientated channels allow cooled air to be transported laterally across the face of a side wall with- out a need to provide a supply duct which runs the entire length of the con- tainer.

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 thereof.