Perishable food items are usually delivered to supermarkets, delicatessens, comer shops and similar stores by road, carried in refrigerated vans and trucks. As perishable food has to be maintained at a temperature usually significantly below ambient temperature to remain fresh, the managers of the stores to which the food is being delivered will not accept delivery of the food if the internal temperature of the vehicle containing the food is above a certain temperature when the vehicle first arrives at the delivery dock of the store.

Although the internal temperature of the vehicle may be satisfactory when first loaded with the food items, as it is rare for a single store to require a full load of food in a single delivery, such vehicles thus transport a number of individual deliveries to differing locations and the opening of the vehicle for each successive delivery results in a raising of the internal temperature, often to a point where delivery is not accepted by a store manager as the internal temperature of the vehicle, and thus the food items that it carries, is outside of acceptable limits. The delivery vehicle is thus unable to deliver its full load and has to return to its depot or other location whereupon the non-delivered food is disposed of. This inability to deliver a full load per vehicle and the consequent wastage of food leads to higher running costs for the transport company and food manufacturers which, eventually, results in higher food prices for the consumer.

There have been a number of prior art attempts to overcome these difficulties -most employing some form of curtain assembly which rides on tracks affixed to the inner wall panels of a truck. In these prior art assemblies, the curtains

can be removably positioned along the length of the truck as the truck is successively emptied of goods, thus reducing the air space around this remaining cargo and therefore assisting to maintain them at the required lower temperature prior to the next delivery. However, these prior art assemblies suffer from a number of disadvantages including (a) complicated fixture fittings to support and operate the assemblies; (b) only offering a fixed number of positions of the curtains along the tracks as goods are emptied from the truck; and (c) make no allowance for the manufacturing tolerance in width of the cargo area of the truck throughout its length thus often making re-positioning of the curtain assemblies down the length of the cargo area difficult as this width varies.

It is therefore a general object of the present invention to overcome, or at least ameliorate, one or more of the above disadvantages.

According to the present invention, there is provided a curtain track assembly for a vehicle of the type having at least a first wall opposite a second wall, said assembly including: a first track fixed to said first wall; a second track fixed to said second wall and running substantially parallel to said first track; and a third track having one end slidably engaged with said first track and having its other end slidably engaged with said second track, said third track being adapted to allow at least one curtain to be drawn along said third track to provide a thermal barrier within said vehicle;

wherein the position of said third track is infinitely ajustable along said first track and said second track.

Preferably, said one end is a biased frictional fit against an inner surface of said first track and said other end is a biased frictional fit against an inner surface of said second track.

Preferably, disengagement of said one end simultaneously disengages said other end to allow said third track to be moved along said first track and said second track.

Preferably, said second track is fixed at substantially a same level as said first track.

Preferably said first track and said second track run substantially in a direction from front to rear of said vehicle.

Preferably, said third track is adapted to accommodate two of said curtain, each of said curtain running in a respective separate track.

The invention will now be described with reference to a preferred embodiment which is shown in the accompanying drawings, in which: FIG. 1 is a schematic illustration of a curtain assembly constructed in accordance with the present invention fitted to a vehicle; FIG. 2 is a cross-section of the first track used in the assembly of FIG.

1;

FIG. 3 is a schematic illustration of a third track used in the assembly of FIG. 1; FIG. 4 is a cross-section of a component of the third track of FIG. 3; FIG. 5 is a schematic illustration of another component of the third track of FIG. 3; FIG. 6a is a schematic illustration, partly exploded, of a runner and curtain used in the assembly of FIG. 1; FIG. 6b is a side elevation of the runner of FIG. 6a; and FIG. 7 is a schematic illustration of a runner and two curtains used in the assembly of FIG. 1.

Referring to FIG. 1, there is partly illustrated the cargo area (1) of a refrigerated vehicle. The cargo area includes at least a first side wall (2), a second opposite side wall (3) and a roof (4).

A first track (5) is fixed to the inside of the side wall (2), at or near the intersection of the side wall (2) with the roof (4). The cross-sectional profile of the track (5) is illustrated in FIG. 2 and is essentially of square C-section.

There is a raised ridge (16) on the lower arm of the C-section which runs the full length of the track (5) and has a concave upper surface (17). The track (5) runs substantially the full length of the cargo area.

A second track (6), of identical profile to the first track (5), is affixed at or near the intersection of the side wall (3) and the roof (4) and also runs substantially the full length of the cargo area.

A third track (7), as more fully illustrated in FIGS. 3 to 5, comprises a central member (8) of cross-section as depicted in FIG. 4. The central member (8) includes a hollow cavity (9) running the full length of the member (8). The lower face of the member (8) is shaped to provide two channels (10,11), each channel (10,11) running the full length ofthe member (8). Stop pins (21a, b) span the channels (10,11) at or near the respective ends of the member (8).

At each end of the member (8) are respective short arms (14,15), each of a profile as illustrated in FIG. 5. As illustrated in FIG. 5, each arm (14,15) is essentially rectangular in cross-section and includes a cavity (18) running the full length thereof. The lower surface of each arm (14,15) is concave (19).

Stop pins (20a, b) span the concave (19) space at or near the respective ends of each arm (14,15). The dimensions of each arm (14,15) are such that each is a slidable fit within the respective tracks (5,6), one or more ball bearings being accommodated within the cylindrical space created between the concave surfaces (17,19) when assemble as illustrated in FIG. 1. Each arm (14,15) includes a respective extension (35,36) affixed approximately mid- length along the respective arms (14,15) to form a substantially T-shaped component. The extension (35) of the arm (15) is hollow and retains a tension spring (38). The lower end of the extension (36) of the arm (14) has a rod (39) extending therefrom into the hollow cavity (9) of the member (8). A second rod (40) is screw thread attached orthogonal to the rod (39) and extends through a short slot (41) in the lower surface of the member (8). The member (8) and arms (14,15) and their associated components are adapted such that, when assemble and in use, the spring (38) bears upon a stop pin (42) fitted within the member (8) such that the outer surfaces of the arms (14,15) are a biased frictional fit against the inner surfaces of the respective tracks (5,6) and by moving the rod (40) in the direction"D" (FIG. 3), the arm (14) can be disengaged/engaged from this frictional fit within the track (6) thus enabling the member (8) to be slid more easily along the tracks (5,6).

Each channel (10,11) can accommodate a shaped curtain runner (22) as illustrated in FIGS. 6a, 6b & 7. The curtain runner is essentially of square C- section (23) the side face (24) of which has been extended and terminates in a concave channel (25). The channel (25) terminates short of one end (26) of the runner (22). A spring-biased bar (27) pivots about a pin (28) and is operated by a pull chord (29). The section (23) accommodates a complementary shaped rod (30) to which is affixed a curtain (31). The curtain (31) is manufactured from any suitable material known in the art which exhibits thermal insulating properties.

In use, typically, the present invention will be installed in a refrigerated van or truck. The food or other perishable items are stacked in the cargo area (1) in the normal manner. The arms (14,15) affixed to the transverse member (8) slide within the tracks (5,6) and thus can be positioned at any required position along those tracks (5,6). To assist loading, the two curtains (31) are initially overlapped and positioned as convenient along the transverse member (8) which, in turn, is positioned as convenient along the tracks (5,6). Upon completion of loading, (a) the transverse member (8) is slid into the required position along the tracks (5,6) and (b) the curtains (31) are slid along the transverse member (8) until their respective spring-biased bar (27) engages the respective lock pin (21 a, b). When unloading, either one or both curtains (31) are unlocked by pulling down on the respective chord (29) to disengage the respective lock pin (21a, b) and the curtain (s) moved aside to enable access to the load. However, as the curtains are thermal and, in any position, still shield a significant portion of the load from the environment outside of the cargo area, the insulating properties of the cargo area are not diminished rapidly while goods are unloaded. The curtains are redrawn and repositioned along the side tracks (5,6) thus providing further assistance in maintaining the internal temperature of the cargo area as the van or truck travels to the next delivery.

The present invention offers a number of advantages not available from the known prior art assembles, including: a. the position of the thermal curtain-carrying track is infinitely ajustable along the length of the cargo area of a vehicle; b. the biased third track automatically takes up any manufacturing tolerances in the width of the cargo area as the curtain-supporting track is moved within the vehicle, providing a smooth-running curtain track which does not bind; and c. the simpler construction is cheaperto manufacture, has less parts to mal function, and can be readily removed and positioned in another vehicle.

It will be appreciated that the above described embodiments are only exemplification of the various aspects of the present invention and that modifications and alterations can be made thereto without departing from the inventive concept as defined in the following claims.