1 VEHICLE CARGO NET FIELD OF THE INVENTION The present invention relates to a cargo net for restraining a load travelling in vehicles on trays, trailers, roof racks, boots, and the like. BACKGROUND TO THE INVENTION It is necessary to ensure that loads travelling in vehicles are restrained to prevent damage to the loads, damage to the vehicles and injuries to drivers and innocent bystanders. This is especially the case in open topped trays such as those on utility vehicles, trucks and roof racks, and in open topped trailers. Conventional cargo nets include a lattice-like web of plastic, rubber or polyester material which fits over the load, with hooks, holes or loops extending from various points on the web to connect to mating holes or hooks on the vehicle or trailer. Alternatively the web may have holes in the material to allow rope to be inserted through and tied onto points on the vehicle or trailer. One problem with conventional cargo nets is that they are not designed to secure a load from theft. A potential thief can easily remove the cargo net from the vehicle, or cut the material web, to access the load. In many cases this makes open topped trays and trailers for the transport of loads unsuitable. It is accordingly desirable to provide a cargo net that can be used to secure loads from theft. SUMMARY OF THE INVENTION In one aspect, the present invention provides a cargo net for restraining a load on a vehicle, the net including a web formed of one or more straps connected in a 2 lattice-type arrangement; at least one first lockable strap extending longitudinally along the web, and at least one second one lockable strap extending laterally along the web, said first and second lockable straps including a cut-resistant material; and each end of the first and second lockable straps being arranged to allow connection to a locking device for securing to the vehicle. The cut-resistant material may comprise a steel wire or steel chain links, which are strong enough to withstand simple cutting with scissors, knife or similar sharp instrument. The locking device may comprise a padlock or combination lock. Each end of the first and second lockable straps may include one or more of: a grommet hole or a snap hook, a carabiner, a circular ring, or a hook and keeper fitting, for connecting to the respective lockable device. The lockable device(s) may include, a Padlock, a combination Padlock, a combination lock Snap Hook or a combination lock carabiner, or a combination of two or more thereof, attached either direct to the cargo net grommet hole(s) or circular rings(s) or the extended arms, or by using a separate length of the cargo net webbing with these lockable devices attached. The length of the first lockable strap may extend beyond the edge of the web to allow for securing the net to differently sized vehicles and various vehicle attachment arrangements. The combination of a cut-resistant material and a locking device provides a lockable cargo net that can be used to secure loads from theft. A potential thief will be unable to easily cut the material forming the lockable straps with scissors or a knife or similar sharp instrument to lift out the load from the vehicle. Securing the ends of the lockable straps to the vehicle using locking devices prevents a thief from easily being able to remove the cargo net from the vehicle.
3 BRIEF DESCRIPTION OF THE DRAWINGS Illustrative embodiments of the present invention will now be described with reference to the accompanying figures. Further features and advantages of the invention will also become apparent from the accompanying description. Figure 1 is a plan view of a cargo net according to one embodiment of the invention; Figure 2 is a plan view of a cargo net according to a second embodiment of the invention; Figures 3A, 3B, 3C and 3D show various embodiments of connection means which may be used to attach the cargo net to the vehicle; Figures 4A and 4B show two embodiments of a cut-resistant material, being steel link chains. DESCRIPTION OF PREFERRED EMBODIMENTS The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. Figure 1 shows a cargo net 1 including a plurality of longitudinal 2 and lateral 3 straps forming a lattice-type web arrangement. At each of the cross over points 4 of the longitudinal 2 and lateral 3 straps there is a grommet hole 4 through the two straps 2, 3 for holding the straps 2, 3 in the desired position. The straps 2, 3 are ideally made of polypropylene or polyester material, although any other material that is suitable for the purpose, and ideally meets Australian standard AS/NZS 43800:2001 could be used. Four lockable straps 5, 6, 7, 8 are formed of a cut resistant material, or formed by inserting a cut-resistant material into the strap, a cut resistant material being one that is not easily cut with scissors, knife or a sharp instrument, such as flexible steel wire or flat steel link chain as shown in Figures 4A and 4B. This results in the load being secured from possible theft from simply cutting through the lockable straps with everyday household cutting implements, as the thief will be unable to cut through the lockable straps to make a large enough hole to lift out the load underneath. Figure 2 shows an alternative embodiment of a cargo net 1, showing the lockable straps 6, 7, 8 extending from three sides of the lattice. The lockable straps 5, 6, 7, 8 may be the same length as the remaining straps, or may extend beyond the length or width of the webbing, as shown by straps 7, 8 in Figure 1, and 6, 7, 8 in Figure 2. The extended straps may have hook and loop (Velcro@) tape 9, a Snap or Carabiner Hook attached to the straps to allow the extended straps to be attached back to the main web when not in use for ease of transport. Attached to each end of the lockable straps 5, 6, 7, 8 is means for connecting a locking device, such as a padlock or a combination lock, to then connect to a mating hole/location on the vehicle. The means for connecting the locking device may include grommet holes 4, circular rings 10, combination lock snap hooks, carabiners, hook and keeper fittings, or any other means to connect to the locking device. In alternative embodiments the locking device may be sewn into the end of the strap.
5 The locking device allows the net 1 to be securely locked to the vehicle to prevent a potential thief from easily removing the net 1 from the vehicle. Figures 3A, 3B, 3C and 3D show various locking devices and connection means for connecting the straps of the cargo net to the vehicle. Figure 3A shows a padlock/combination lock, which may be locked with a key or a combination code. Figure 3B shows a combination lock carabiner lock/hook. Figure 3C shows a hook and keeper style fitting at one end. Figure 3D shows grommet holes along the webbing strap. A carabiner, snap hook, rope, padlock or other connection device may be inserted through some or all of the remaining grommet holes, if additional tie downs to the vehicle are desired. In some implementations, the number and arrangement of the lockable straps will vary, for example depending upon the size of the cargo, tray/trailer and vehicle. The arrangement shown in Figures 1 and 2 is illustrative only and may only suit certain types of vehicles. There should be a sufficient number and arrangement of lockable straps to not allow the load underneath to be easily lifted out from the vehicle. The net of the present invention could be used to secure loads on many types of vehicles, including utilities, trays, truck backs, rubbish tip bins, trailers or roof racks. Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment.
6 Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations. It will be appreciated that persons skilled in the art could implement the present invention in different ways to the one described above, and variations may be produced without departing from its spirit and scope. Any discussion of documents, devices, acts or knowledge in this specification is included to explain the context of the invention. It should not be taken as an admission that any of the material forms part of the prior art base or the common general knowledge in the relevant art, in any country, on or before the filing date of the patent application to which the present specification pertains.