The present invention relates to a trailer, and particularly, a side wall system for converting a trailer between an open flat bed configuration and a cargo box configuration trailer. The present invention also relates to a cargo compartment or 'box body' for mounting to the chassis of a trailer or a vehicle, the cargo compartment having a side wall system for converting the compartment between an open flat bed configuration and a cargo box configuration. Flatbed trailers are used in trucking due to their versatility in terms of the type of cargo they can be used to transport, as well as their ease of loading and unloading. However, they suffer from the drawback that the cargo being carried by them is left exposed to the elements due to the open unenclosed nature of the flatbed trailer. Some bespoke solutions have been proposed to address this inherent disadvantage, including interconnecting frame type panel systems which require operatives to manually construct and attach side walls around the perimeter of the trailer to convert the trailer from a flatbed arrangement to a cargo box configuration. However, these solutions are unsatisfactory as it is an extremely time consuming and onerous task for operatives to manually assemble and when required disassemble the side walls.

It is a therefore an object of the present invention to provide a side wall system for a flat bed trailer which goes at least some way toward overcoming the above problems and/or which will provide the public and/or industry with a useful alternative. It is a further object to provide a roofing system for use with the side wall system.

It is a still further aspect of the invention to provide a cargo compartment comprising such a side wall system, the cargo compartment being adapted for mounting to the chassis of a trailer or the chassis of a vehicle.

It is acknowledged that the term 'comprise' may, under varying jurisdictions be provided with either an exclusive or inclusive meaning. For the purpose of this specification the term comprise shall have an inclusive meaning - i.e. that it may be taken to mean an inclusion of not only the listed components it directly references, but also other non- specified components. Accordingly, the term 'comprise' is to be attributed with as broader interpretation as possible within any given jurisdiction and this rationale should also be used when the terms 'comprised' and/or 'comprising' are used.

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

According to one aspect of the invention, there is provided a trailer convertible between an open flat bed configuration and a cargo box configuration, the trailer comprising:

a flat bed mounted on a chassis,

a side wall which extends upwardly on the flat bed,

characterised in that the side wall is divided into a two or more side wall panels which are operable to move from a first operative position in which they form at least a portion of a cargo box on the flat bed, to a second operative position in which they are located substantially below the flat bed adjacent the chassis to provide an open flat bed configuration.

The present invention thus provides a trailer having cargo box with a side wall or side walls that is/are configured to move down to provide an open flat bed configuration for loading the trailer.

Preferably, the two or more side walls panels comprise an upper panel and a lower panel, the upper panel located above the lower panel when in the first operative position.

Preferably, the upper panel is adapted to move down into the lower panel when moving to the second operative position.

Alternatively, the upper panel is adapted to move into substantial co-alignment beside the lower panel when moving to the second operative position.

Preferably, the upper panel and the lower panel are configured to move together outwardly of the flat bed and then down to a position adjacent the chassis of the trailer. Preferably, the upper panel and lower panel are moved between the first operative position and the second operative position by rams.

Ideally, the side wall or walls are divided into a pair of side wall panels. Alternatively, the side wall or side walls may be divided into any number of interconnected panels, including three, four or more panels as desired.

In another embodiment of the invention, the trailer comprises two side walls, a front wall and a rear door, each side wall being divided into two or more side wall panels which are operable to move from a first operative position in which they form at least a portion of a cargo box on the flat bed, to a second operative position in which they are located below the flat bed substantially adjacent the chassis.

It will be appreciated that the rear door may comprise any suitable arrangement of closure members, for example, but not limited to, one or more vertically or horizontally hinged doors, or sliding doors or hatches.

The present invention thus provides a trailer which is multi-functional due to its side loading/unloading, overhead loading and rear tipping properties.

Preferably, the trailer further comprises a roof. Preferably, the roof is retractable. Preferably, the trailer is adapted to be pivoted on the chassis. In another aspect of the invention, there is provided a cargo compartment convertible between a substantially open flat bed configuration and a cargo box configuration, the cargo compartment comprising:

a flat bed mountable to the chassis of a vehicle or trailer,

a side wall which extends upwardly on the flat bed,

characterised in that the side wall is divided into two or more side wall panels which are operable to move from a first operative position in which they form at least a portion of a cargo box on the flat bed, to a second operative position in which they are located substantially below the flat bed adjacent the chassis to which the cargo compartment is mounted to provide an open flat bed configuration. The present invention thus provides a cargo compartment adapted for mounting to a trailer or vehicle chassis and having a side wall that is configured to move down to provide an open flat bed configuration for loading the cargo compartment. Preferably, the two or more side wall panels comprise an upper panel and a lower panel, the upper panel located above the lower panel when in the first operative position.

Preferably, the upper panel is adapted to move down into the lower panel when moving to the second operative position.

Alternatively, the upper panel is adapted to move into substantial co-alignment beside the lower panel when moving to the second operative position.

Preferably, the upper panel and the lower panel are configured to move together outwardly of the flat bed of the cargo compartment in use, and then down to a position adjacent the chassis of the trailer or vehicle upon which the cargo compartment is mounted.

Preferably, the upper panel and lower panel are moved between the first operative position and the second operative position by rams.

Conveniently, the rams may be contained on the flat bed.

Ideally, the side wall or walls are divided into a pair of side wall panels.

Alternatively, the side wall or side walls may be divided into any number of interconnected panels, including three, four or more panels as desired.

In another embodiment of the invention, the cargo compartment comprises two side walls, a front wall and a rear door, each side wall being divided into one or more pair(s) of side wall panels which are operable to move from a first operative position in which they form at least a portion of a cargo box on the flat bed, to a second operative position in which they are located below the flat bed substantially adjacent the chassis of the trailer or vehicle upon which the cargo compartment is mounted. The present invention thus provides a separable cargo compartment or 'box body' adapted for mounting to a trailer or vehicle chassis and which is multi-functional due to its side loading/unloading, overhead loading and/or rear tipping properties. Preferably, the cargo compartment further comprises a roof. Preferably, the roof is retractable.

Preferably, the cargo compartment is adapted to be pivoted on the chassis of a trailer of vehicle to which it is mountable.

Optionally, the embodiments of the invention further comprise a refrigeration means so that perishable, chilled or frozen goods can be transported in a trailer or vehicle having a cargo compartment in accordance with the invention. The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of a trailer according to the invention;

Fig. 2 is a perspective view of the trailer shown in Fig. 1 with an upper panel of the side wall lowered into a lower panel of the side wall;

Fig. 3 is a perspective view of the trailer shown in Fig. 2 with the side wall panels side shifted;

Fig. 4 is a perspective view of the trailer shown in Fig. 2 with upper and lower panels of a side wall retracted; Fig. 5 is a perspective view of the trailer shown in Fig. 4 with both side walls retracted;

Fig. 6 is an end sectional view of the trailer in Fig. 1 showing a configuration of the side wall panels; Fig. 7 is an end sectional view of the trailer shown in Fig. 2 showing the upper panel inside the lower panel of a side wall;

Fig. 8 is an end detailed sectional view of the trailer shown in Fig. 1 showing rams operative to lower and raise the upper panel into and out of the lower panel of the side wall;

Fig. 9 is an end sectional view of the trailer shown in Fig. 5 showing the rams operative to side shift and lower the upper and lower panels of the side walls to the ground around the chassis of the trailer;

Figs. 10a to 10c are perspective views of a ram used to effect the movement of the side wall shown in Fig. 9; Fig. 1 1 is an end sectional view of the trailer illustrating the loading of cargo;

Fig. 12 is a perspective view of the trailer showing the operation of the roof;

Fig. 13 shows the tipping function of the trailer; and

Figs. 14a, 14b and 14c show an exemplarily cargo compartment in accordance with the invention mounted to the chassis of a vehicle.

Referring to the Figs 1 to 13, there is shown a trailer, indicated generally by the reference numeral 1 , convertible between a cargo box configuration, as shown in Fig. 1 , and an open bed configuration, as shown in Fig. 5. The trailer 1 comprises a flat bed 2 mounted on a chassis, indicated generally by the reference numeral 3. It will be understood that the chassis 3 is the part of the trailer 1 which supports the flat bed platform 2 and is mounted on wheels or casters. The trailer 1 also comprises a front wall 15 and rear doors 16.

The trailer 1 further comprises at least one side wall, indicated generally by the reference numeral 4 which extends upwardly on the flat bed 2. The side wall 4 is divided into a pair of side wall panels, namely an upper panel 5 and a lower panel 6. Although reference throughout the following will be made to the side wails 4 of the present invention comprising of a pair of side wall panels 5, 6, it will be understood that each side wall 4 could be made up of any number of interconnected panels, including three, four or more panels, as required or as desired. Reference to a side wall 4 comprising an upper panel 5 and a lower panel 6 should therefore not be seen as limiting. Similarly, although not shown in the drawings, it will be appreciated that the at least one side wall may comprise one or more side wall segments which together define the side wall, each side wall segment being made up of any number of interconnected panels. Such side wall segments may be independently operable so that side access to a specific portion of the flat bed can be achieved.

The present invention provides a trailer 1 in which the or each side wall 4, is operable to move from a first operative position in which it forms at least a portion of a cargo box on the flat bed 2 (as shown in Figs. 1 and 2), to a second operative position in which the side wall 4 is located substantially below the flat bed 2 adjacent the chassis 3 to provide an open flat bed configuration (as shown in Fig 5).

To move from the first operative position to the second operative position, the upper panel 5 of each side wall 4 is adapted to initially move down inside the lower panel 6 as it rests on the flat bed 2, as shown in Figs. 6 and 7. The panels 5, 6 are thus hollow panels. Alternatively, the upper panel 5 may move into substantial co-alignment beside the lower panel 6 as it rests on the flat bed 2. The upper panel 5 and the lower panel 6 are then configured to move together outwardly of the flat bed 2 as shown by reference arrow 'A' in Fig. 3 and then down to a position adjacent the chassis 3 of the trailer 1 , as shown in Figs. 4 and 5.

The movement of the side walls as shown in Figs. 1 to 7 is effected by the use of rams. As shown in Fig 8, each side wall 4 comprises internal side wall rams 8 which are operable to raise and lower the upper panel 5 into and out of the lower panel 6. Such internal side wall rams 8 may be positioned toward the front and the rear of the trailer 1 as required or as desired to ensure the smooth operation and movement of the upper and lower panels. In use, as the arm 9 of ram 8 is retracted it draws the upper panel 5 into the lower panel 6. Conversely, movement of the ram arm 9 upwards extends the upper panel 5 out of the lower panel 6 to thereby close the side wall 4 and return the trailer 1 to the enclosed cargo box configuration. Figs. 9 and 10 show the use of rams 10, 13 to effect side shift and drop down functions of the present invention. The rams 10 are ideally contained on the trailer between the chassis 3 and the flatbed 2 as shown in Fig. 9. Alternatively, they may be contained on the flat bed as shown in Fig. 8. Each ram 10 comprises a side shift arm 1 which extends in the direction of arrow 'B' (Fig. 10b) to initially push the lower panel 6 and upper panel 5 together outwards from the edge of the flat bed 2. The panels 5, 6 are then lowered to the ground level adjacent the chassis 3 using the drop down arm 12 of the ram 13, the drop down arm 12 moving down in the direction of arrow 'C (Fig. 10c) to provide an open bed configuration. Cargo 20 may be loaded onto the flat bed through the open sides of the trailer 1 with the side wall panels 5, 6 at the side of the chassis 3 substantially below the flat bed 2 adjacent the wheels, as shown in Fig. 11. The trailer 1 may be returned to the cargo box configuration by appropriate actuation of the ram 13 so that arm 12 raises the panels 5, 6 from the ground and then actuation of the side shift arm 11 of ram 10 may draw the panels 5, 6 back into line at the edge or perimeter on the flat bed 2. Finally actuation of ram 8 moves the upper panel 5 above the lower panel 6 to form the side wall 4.

As shown in Fig. 12, the trailer 1 further comprises a roof 17. Roof 17 is retractable. As shown in Fig. 12, roof 17 may comprise a shutter or sheet style roller roof movable along a frame or suitable guide rails 171 and which allows for safe carriage of palletised goods and facilitates the loading of loose aggregate from above. The roller roof 17 is optionally sealable and may optionally operate on electric motors powered by the trailer . It will be appreciated that the roof may comprise any suitable roof type, for example, it may comprise a canvas or plastic roof that may be retracted and closed by rolling or sliding. The trailer 1 is further adapted to be pivoted by ram 21 on the chassis 3, as shown in Fig. 13.

As shown by way of example in Figs. 14a, 14b and 14c, in a further embodiment of the invention, there is provided a cargo compartment or 'box body' indicated generally by the reference numeral 100 that is adapted for mounting to the chassis 30 of a vehicle 50 or to the chassis of trailer. In this way, the cargo compartment is a separable unit that can be fitted to the rolling chassis 30 of a truck or trailer. Cargo compartment 100 operates substantially as described above with reference to Figs 1 to 13 i.e. is convertible between a substantially open flat bed configuration and a cargo box configuration and is provided with a rear door 16 arrangement and optionally comprises a retractable roof. In Figs. 14a- 14c, cargo compartment 100 is shown as being pivotally mounted to chassis 30 of a vehicle 50 in a tipping configuration, however, it will be appreciated that the compartment can be rigidly mounted to the chassis 30 of a vehicle or trailer. Cargo compartment 100 comprises a flat bed 200 mountable to the chassis 30 of a trailer or vehicle. Cargo compartment 100 further comprises at least one side wall 4 which extends upwardly on the flat bed 20. The side wall 4 is divided into a pair of side wall panels, namely an upper panel 5 and a lower panel 6. Although reference throughout the following will be made to the side walls 4 of the present invention comprising of a pair of side wall panels 5, 6, it will be understood that each side wall 4 could be made up of any number of interconnected panels, including three, four or more panels, as required or as desired. Reference to a side wall 4 comprising an upper panel 5 and a lower panel 6 should therefore not be seen as limiting. Similarly, although not shown in the drawings, it will be appreciated that the at least one side wall may comprise one or more side wall segments which together define the side wall, each side wall segment being made up of any number of interconnected panels. Such side wall segments may be independently operable so that side access to a specific portion of the flat bed can be achieved. Conversion of the cargo compartment 100 between a substantially open flat bed configuration and a cargo box configuration is effected by rams substantially as described above with reference to Figs 1 to 13. In this embodiment of the invention, rams (not shown) which effect side shift and drop down function are ideally contained on the flat bed. Alternatively, they may be contained on the chassis to which the compartment is mountable.

Cargo compartment 00 therefore provides a compartment in which the or each side wall is operable to move from a first operative position in which it forms at least a portion of a cargo box on the flat bed 200 (as shown in Figs. 14a - 14c), to a second operative position (not shown) in which the side wall is located substantially below the flat bed adjacent the chassis to which the cargo compartment is mounted to provide an open flat bed configuration.

In this way, the present invention thus further provides a separable cargo compartment or box body adapted for mounting to a trailer or vehicle chassis and having a side wall that is configured to move down to provide an open flat bed configuration for loading the cargo compartment. In this way, cargo compartment is multi-functional due to its side loading/unloading, overhead loading and/or rear tipping properties. The various embodiments of the invention described above may further comprise a refrigeration means (not shown in the Figs.) so that perishable, chilled or frozen goods can be transported in a trailer or vehicle having a cargo compartment in accordance with the invention.

Aspects of the present invention have been described by way of example only and it should be appreciate that additions and/or modifications may be made thereto without departing from the scope of the invention as defined in the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments.