GB2169997A - Refrigerated containers - Google Patents

Abstract

A refrigerated container 10 has a mobile refrigeration unit 11 which is stowed internally during transportation and is removed and coupled externally to the container in use. The refrigeration unit 11 comprises the compressor and condensor components of the refrigeration system whereas the generator and blowers are mounted in the container. <IMAGE>

Description

SPECIFICATION Refrigerated container THIS INVENTION relates to improvements in refrigerated containers.

Present refigerated containers are based on modified shipping containers, for example, the ISO type. Because such containers have relatively thin walls, with poor insulation factors, relatively large refrigeration and/or chiller units are required to cool or chill the products stored in the containers.

In addition, because of their high tare weight and corner mounted lifting sockets, specialised equipment is required for their transport and positioning. Finally, they cannot be divided into two or more compartments so as to enable cooling and chilling of different classes of goods in the same container.

In providing refrigeration plants in containers of the above type, a loss of internal volume results and where the size of the refrigeration plant is necessarily large in order to effectively cool poorly insulated existing containers, the volume lost from the storage volume is considerable.

It is an object of the present invention to provide a refrigerated container which enables a greater portion of its internal volume to be devoted to storage of goods than has been possible to date whilst retaining all the useful characteristics of containers as regards their transport between sites.

Other objects and advantages of the present invention will hereinafter become apparent.

The invention achieves it objects by providing a refrigerated container for transport between sites comprising a refrigerated compartment having a door thereto and a refrigeration unit movable through said door between a storage position internal of said compartment and an operative position external of said compartment, said refrigeration unit housing a condenser communicated via disconnectable, refrigerant lines with at least one evaporator within said container.

The invention will now be more particularly described with reference to the accompanying drawings which illustrate a preferred embodiment and wherein: Figure 1 is a cut-a-away perspective view of a refrigerated container in accordance with the present invention, with the refrigeration unit in its storage position within the container; Figure 2 is a cut-a-away perspective view of the refrigerated container of Figure 1 from behind, showing the refrigeration unit in its operative position.

In Figure 1, a refrigerated container 10 is divided into two compartments by an internal wall 12, and a refrigeration unit 11 is shown stowed centrally of the refrigerated container 10 against the internal dividing wall 12. In Figure 2, the refrigeration unit 11 is shown in its operative position external to the refrigerated container 10. The refrigeration unit 11 houses the motor, compressor, and condenser components of the refrigeration plant utilised in cooling the container with a separate evaporator and blower unit being provided in each compartment, these being units 13 and 14.

In its storage position, the refrigeration unit 11 may be stowed by utilising floor mounted anchor points connected to the four corners of the refrigeration unit to hold it in place during transport.

Corner plates, such as 15 (Figure 2), may be holed for engagement with a connecting element 16 (Figure 1) which may be a linkage with a turnbuckle to enable its tensioning.

When the refrigeration unit is to be operated it may be disconnected from its anchor points and rolled out of the refrigeration container on its wheels, such as 18, down a ramp 17. The refrigeration unit 11 is connected to the refrigerated container 10 by plugging releasable refrigeration lines 20 into coupling points on the wall of the refrigerated container 10, which couplings may be housed behind a protective flap 19 hingeably connected to the container wall. The refrigeration lines 20 may be folded away inside the refrigeration unit 11 during transport behind a door 21. The refrigeration unit 11 may be moved about manually using hand grips at each corner, such as grip 22 (Figure 2).

The refrigeration unit 11 is constructed with vented side panels 42 (Figure 2) to allow the requisite air flow over a condenser therein.

The refrigerated container may be constructed from panels of insulated sheet material joined appropriately along the edges thereof, and constructed over a load bearing floor. In order to facilitate transport, lifting points may be provided so as to enable the container to be slung beneath a crane, helicopter, etc. In doing this a lifting sling is connected at four points 23 to 26, being holed lifting plates attached to a lifting frame comprised of vertical straps, such as 27 to 29, extending from a top frame 30 to the load bearing floor so as to transmit the weight on the floor to the lifting points. The top frame 30 may comprise a rectangular array of elements, diagonally braced as shown, to establish a rigid structure between the lifting points.Conveniently, flat members with plate-like corner gussets are employed so as not to unduly increase the external dimensions of the container.

These members are joined by any convenient manner having regard to the forces applied thereto during lifting, which might possibly be done in a loaded state so that weights greater than that of the unloaded container might be taken account of.

The refrigerated container may be constructed with wall panels having inner and outer sheets of material with a thermal insulation therebetween.

So as to reduce weight, cladding sheets of aluminium may be used with a foam insulation between.

The cladding sheets may be ribbed as is the usual practice, and the ribs should be run horizontally so as to allow flexing of the wall panels during lifting should flexing occur. Rear wall 31 is shown with ribs 32 (Figure 2) running horizontally thereacross.

To protect the container 10 against knocks, a kick rail 33, and a middle rail 34, may be provided about the perimeter of the container. These may be extrusions of a suitable material, having selected cross sections such as that shown in the drawings.

Construction of the refrigerated containers may utilise corner eiements being extrusions, etc. such as 35, providing perpendicular surfaces to which cladding sheets may be riveted. Any of the standard refrigerated door structures may be mounted in the walls of each of the compartments. Door 36 is shown closed, and door 37 is open to show vertically dependent plastic strips 38 which restrict the outflow of internal cooled air in the manner now well known in these applications. In order to enable operation of the doors, the usual venting structures are mounted to a wall of each compartment and a temperature sensor with an externally viewable guage 39 may also be employed to enable the internal temperature to be monitored.

The load bearing floor may incorporate a pair of opposed skids 40 and 41 so as to enable the container to be loaded and unloaded to and from a tilting tray truck as is known with similar containers. The skids may be employed as structural beams in the load bearing floor.

The above described container enables construction of a prefabricated unit with a degree of insulation enabling use of a refrigeration unit operable from a 240 volt single phase supply, with temperatures between -18 and +18"C being readily achieved thereby. The container may then be employed for on-site storage of products, including foodstuffs, cut flowers, etc. A fully sealed refrigerant compressor is preferred. The evaporator units, and electric blowers for circulation of cold air, are fixtures within their compartments, located to provide the most efficient air circulation with the maximum usable storage space retained. The refrigeration plant is preferably selected to be capable of pulling and holding the set temperatures required in both storage compartments simultaneously, and it is to be able to set different temperatures in the two compartments.Each compartment is controlled by its own thermostat. Self sealing quick connectors are provided for coupling the refrigeration unit and the containers together in use.

The refrigeration pipe work of the container is preferably incorporated within the walls of the container. Electrical wiring for lighting etc., may be internal of the walls, or externally conduited. The pressure relief vents are electrically heated, as is known, to prevent condensation building up so as to block their operation. The surrounds of the doors are also electrically heated to prevent their being frozen shut.

The wall panels may be 150 mm thick with a colour bond' skin inside and out. The floor may employ a non-skid plate material and is internaily finished with a 150 mm skirt up the internal walls to form a 'kick board'. Any steel framing should be galvanised. All panel joins, rivets, etc. should be sealed. The foam insulation may be expanded polystyrene.

The above set out two compartment structure enables different foodstuffs, etc. which require different storage temperatures, to be stored separately at their own storage temperatures. The dividing wall may be offset from the center to provide compartments of different volume. This enables the refrigeration unit to be stored centrally of the container during transport where its considerable weight does not cause imbalance of the container during transport from a sling.

Claims (12)

1. A refrigerated container for transport between sites comprising a refrigerated compartment having a door thereto and a refrigeration unit movable through said door between a storage position internal of said compartment and an operative position external of said compartment, said refrigeration unit housing a condenser communicated via disconnectable refrigerant lines with at least one evaporator within said container.

2. A refrigerated container as claimed in Claim 1 which is divided by an internal wall to establish two storage compartments, each with an evaporator and control means effective to independently maintain preselected temperatures in said two compartments.

3. A refrigerated container as claimed in either of Claims 1 or 2 wherein connection means are provided in said container whereby said refrigeration unit may be held immobile at its storage position.

4. A refrigerated container as claimed in any one of the preceding claims which is provided with a lifting frame providing overhead connector means whereat lifting lines may be attached.

5. A refrigerated container as claimed in any one of the preceding claims wherein the container is formed of insulated wall panels comprised of an insulation material sandwiched between cladding sheets.

6. A refrigerated container as claimed in any one of the preceding claims wherein said refrigeration unit is connected to said container via self sealing, disconnectable, refrigerant lines plugged into externally provided connectors therefor which lines are stored internally of said refrigeration unit during storage at said storage position.

7. A refrigerated container as claimed in either one of Claims 1 or 6 wherein the refrigeration unit houses a refrigeration motor, compressor and condenser, and said evaporator is provided with at least one air circulation blower means.

8. A refrigerated container as claimed in Claim 2 or any preceding claim dependent thereto wherein said internal wall is set off center of the container to create two compartments having different volumes.

9. A refrigerated container as claimed in Claim 3 of any preceding claim dependent thereto wherein the connection means includes a plurality of linkage means employing a turnbuckle each engaging with plate-like lugs provided on said refrigeration unit at one end and a compartment floor mounted connector point at the other.

10. A refrigerated container as claimed in Claim 4 or any preceding claim dependent thereto where said lifting frame is a cage-like frame provided about the external surface of said refrigerated con tainer, having vertically extending load bearing straps between an overhead frame unit providing said overhead connector means and a load bearing floor to the container.

11. A refrigerated container as claimed in Claim 5 or any preceding claim dependent thereto where the insulated wall panel comprises an expanded polystyrene filler between colour bonded alumium inner and outer sheets.

12. A refrigerated container substantially as hereinbefore described with reference to the drawings.