AU783722B2 - An improved road train - Google Patents

Description

P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventors Address for service is: 4 -ta -L Asce* V 'r^ec P- LA Michael Charles Coote and William Jeffrey Coote WRAY ASSOCIATES Level 4, The Quadrant 1 William Street Perth, WA 6000 Attorney code: WR Invention Title: "An Improved Road Train" The following statement is a full description of this invention, including the best method of performing it known to me:- -2- "An Improved Road Train" Field of the Invention The invention generally relates to the transport of materials and freight by road.

In particular, the invention relates to those vehicles, and combinations of vehicles, that convey these materials and freight. More specifically, the invention relates to road trains, arranged as a combination of prime movers, semi-trailers, trailers and converter dollies.

Background Art Road transport of freight, whether it be in the form of shipping containers, bulk materials or liquids is a cost effective means of transport, subject to fuel prices, distances to travel, and the condition and availability of roads to the required destination etc.

The type of vehicle selected for the road transport of freight is highly dependent on the mass of the freight to be transported, the overall distance to be covered and the infrastructure to be traversed during the journey. In discussing the freight mass, and the corresponding mass of conveying vehicle(s), the standard expressions used to differentiate the capacity of each form of road transport are Gross Vehicle Mass (GVM), for single vehicles, and Gross Combination Mass (GCM) which is the greatest possible sum of the maximum loaded masses of the motor vehicle and any vehicles that may be towed by it at one time.

Using these expressions, for a GVM up to 30 tonnes, rigid trucks are typically utilized. A rigid truck is defined as a truck having a fixed containment, such that freight is unloaded from the containment on delivery. A trailer is a containment vehicle having a forward and rear axle group, and thus is self supporting, and 25 detachable from the driven vehicle.

For larger loads, typically GCM of 24 tonnes to 46 tonnes, and often for longer distances than a truck, prime movers driving semi-trailers are common. A prime -3mover is defined as a motor vehicle, having no inherent containment, but is designed to tow a semi-trailer. A semi-trailer is defined as a containment vehicle having a rear axle group only, with a forward coupling device for connecting to a prime mover.

For an additional freight loading, increasing the GCM up to 68 tonnes, a modified semi-trailer having a coupling arrangement to connect with a second semi-trailer can be included to form a combination of vehicles, this being referred to as a B- Double. In this nomenclature, the refers to the trailer to semi-trailer coupling being capable of transferring a rolling moment from the trailer to the semi-trailer, hence the name "B-Type Coupling". The "Double" refers to there being two containment means as part of the combination.

An alternative to the B-Double is the Road Train, where the containment is exclusively provided by semi-trailers. In this combination, the leading semi-trailer couples directly to the prime mover, and a following semi-trailer is coupled to the preceding semi-trailer via a converter dolly. A converter dolly, is essentially an axle group having a coupling arrangement to couple with the following semitrailer and a drawbar that attaches to the preceding semi-trailer.

A direct extension of either the Road Train and B-Double is the inclusion of a third semi-trailer using a converter dolly. In an identical arrangement to the Road Train, a converter dolly can be linked to the rear semi-trailer, and further semitrailer added, creating either a Triple Road Train or a B-Triple. Thus, this combination provides a GCM of up to 140 tonnes.

-In a final, and less common arrangement, there exists a combination which uses *three semi-trailers and a modified semi-trailer, as described previously. The socalled AB-Quad Road Train provides a GCM of up to 163.5 tonnes.

In determining the applicability of various combinations to specific loads, there exists compliance standards to which operators must conform. Whilst there are recommendations for the introduction of performance based standards, this is -4not yet the case, and in any event, issues of roll stability etc. are critical design features.

Among these requirements set forth by the compliance standards are the maximum length of the combination, the maximum loading for each axle group and the clearance between the rear axle of an axle group to the front axle of the preceding group.

The maximum permissible length of a combination is 53.5 metres, which matches the length of a typical Triple Road Train. From this, it is clear that an AB-Quad Road Train is difficult to construct as shorter semi-trailers and trailers are required in order to fit within the length.

In addition to the maximum length required, there is also a requirement relating to the spacing of axle groups, in this case, ensuring adjacent axle groups are not positioned too close. Thus, for adjacent axle groups, there is a minimum distance requirement of 9.2 metres measured from the front axle of a forward group to the rear axle of a rear group. This minimum distance is specified to limit the applied traffic loads as the road train crosses a bridge, or similar structure.

In addition to the dimensional requirements, there are specified mass limits also, 0 the most critical of which place a 20 tonne maximum load per triple axle, which may conditionally be increased to 23.5 tonnes.

4 "20 Within these rules, operators optimize the variations of combinations so as to increase the viability of their business. Ideally, a single prime mover will tow as "much weight as possible, so as to transport the greatest mass of freight in one trip. To achieve that, as many trailers as practical will be added to the *ilcombination, within the overall length limit of 53.5 metre. Further, each of the 25 semi-trailers will be loaded within the absolute maximum of 23.5 tonnes per triple axle group. By reducing the weight per axle group or the overall length, shorter semi-trailers can be incorporated, subject to the minimum axle group spacing requirement, as discussed previously. By adhering to these limits, a maximum GCM of 163.5 tonnes has been achieved using the AB-Quad Road Train.

In addition to these considerations, further performance measures must be considered, such as load ratio transfer, rearward amplification, yaw damping, high-speed offtracking, low speed off-tracking, road depression response, tracking ad roll stability. Roll stability, in particular, is of significance interest, given the inability of the entire combination to support individual components.

In the semi-trailer to semi-trailer connection, the coupling is via a converter dolly which uses a draw bar to connect to the preceding semi-trailer. Whist this maintains the load imposed by towing, such an element is incapable of transferring a rolling moment from a preceding semi-trailer to a following semitrailer. Thus, if there is contact with an uneven portion of the road, or other application of an overturning force, individual semi-trailers cannot be supported by other semi-trailers within the combination, where the connection is through a converter dolly. Where the coupling is directly with the prime mover or with a trailer having a ball race/turntable coupling, the roll moment can be transferred.

Thus, for the purposes of optimizing a combination, the operator must balance roll stability and operating costs. The use of semi-trailers having ball race/turntable couplings limits choice, increases the capital cost of vehicles and possibly reduces the mass of freight being transported.

A further consideration for optimization of a delivery of freight to a remote site is 20 the cost of the Road Train on the return trip. Unless the site has appropriate freight that can be returned from site, the Road Train will be travelling empty on o• the return leg. In a circumstance where liquid is the primary material being transported, then it is highly unlikely that there will be corresponding return of fluid. It follows that the cost of the two way trip must be offset by the revenue S 25 received from the delivery leg only.

The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material 3 referred to was part of the common general knowledge in Australia as at the 30 priority date of the application.

-6- Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Disclosure of the Invention According to one aspect of the present invention there is provided a trailer support vehicle and semi-trailer combination, the trailer support vehicle for providing an indirect connection from a preceding vehicle to a following semitrailer (described hereinafter), said trailer support vehicle including a support portion for supporting the following semi-trailer, a plurality of axles having an axle centre, said axle centre located directly below the support portion, a first coupling means for coupling the trailer support vehicle to the preceding vehicle and a projection means extending from the support portion to the first coupling means.

The axle centre is defined as the centroid of the collection of axles within the axle group. Therefore, for an axle group having two axles the axle centre will be halfway between the axles and for a triple axle group, the centroid will be at the centre line of the centre axle.

In a preferred embodiment, the projection means may be a stiff member extending from the support portion to the coupling means, which may integrally 20 connect the support portion and the coupling means, or be demountable from the support portion and the coupling means. By providing a stiff projection between the moment transferring support portion and coupling means, this provides one method of ensuring the moment transfer through the trailer support vehicle.

In a more preferred embodiment, the stiff member may be a gooseneck shaped projection. As the coupling means may be positioned above a support portion attached to another vehicle, and the support portion may be positioned below the coupling means of a third vehicle, having a goose-neck shaped portion provides -7an advantageous shape for directing the moment without a discontinuous stress path, that may yield critical stress concentration.

In a preferred embodiment, the trailer support vehicle may be a goose-neck converter dolly, which does not rely on the well-known draw bar, but instead incorporates a goose-neck shaped forward projection that can transfer the rolling moment. This has the advantage of using modified standard equipment to effect a significant improvement to roll stability.

In a preferred embodiment, the trailer support vehicle may have a carrying means for transporting discrete loads. To further add to the cost-effectiveness of trip, by having the trailer support vehicle being capable of carrying further freight, it may be possible to accrue revenues from the return journey.

In a more preferred embodiment, the carrying means may be a platform for transporting additional materials, for example copper cathode from a mine site load. This is particularly useful where the original delivery to site is a liquid, and so freight for the return leg can use either the empty tanks or, if solid, the platforms can be used to support the load directly or provide a base on which loading bins can be mounted.

In a preferred embodiment, the plurality of axles may be three axles. Particularly for liquid freight, but not exclusively so, the issue in transport is not the volume of 20 material, but the mass, and specifically the concentrated mass. In order to comply with maximum axle group loadings, it may be preferable to have a triple axle group so as to increase the allowable loading per group.

In a preferred embodiment, the distance between a leading axle and a rear axle may be at least 1350 mm.

25 In a more preferred embodiment, the distance between a leading axle and a rear S• axle may be 1500 mm.

of a° -8- In a preferred embodiment, the coupling means may be ball race configuration suited for connection to a turntable located on the preceding vehicle. It has been shown that such coupling means provide the transfer of rolling moment to satisfy the rolling stability needed. It should be emphasised that the coupling means are not restricted to the ball race/turntable arrangement, and is to include other means that provide the transfer of rolling moment.

In a preferred embodiment, the support portion may be a turntable suited for connection to a ball race configuration located on the trailer.

In providing coupling assemblies between semi-trailers, dollies and similar types of vehicles there exists a number of different arrangements. The present invention is not to be restricted to any particular type so long as said coupling assembly is capable of transferring a rolling moment and therefore does not include the draw-bar arrangement which is common in the trade but is also known to be unable to transfer the rolling moment. In addition to the aforementioned assemblies another arrangement may be considered being a fully rotatable specialized tow-ball to replace the dolly turntable. Whilst this is S: typically only used for low speeds, for instance up to 70 kilometres per hour, they are particularly useful in increasing mobility and reducing trailer stresses for off highway or rough road applications. Hence the present invention, when referring 20 to the various coupling assemblies may be considered to include this specialized arrangement.

In another aspect of the invention, there is provided a semi-trailer for transporting bulk materials including a containment means for containing bulk materials and a first coupling portion for coupling with a preceding vehicle, each provided on a 25 forward portion of the semi-trailer, and an axle group having a forward-most and S•a rear-most axle and a support portion for connecting to a following vehicle, each provided on a rear portion of the semi-trailer, wherein the support portion is positioned above and forward of the rear-most axle of said axle group, and an axle centre of the axle group is located directly beneath the containment means and adjacent to a rear end of the containment means, such that the axle group -9provides a reaction force to support the containment means. The improved semi-trailer may be used with a gooseneck dolly, whether loads are generally horizontal, and not a semi-trailer, which apply vertical loads, then the rear axle group can assist in directly supporting the improved semi-trailer.

In a preferred embodiment the support portion may be located forward of a rear axle of the axle group. To aid in the steering of following vehicles, having the coupling forward of the rear axle permits following vehicles to be eased into the turn earlier than would be the case of a coupling behind the rear axle. The improved performance may be demonstrated by a markedly improved low-speed offtracking and, more importantly, may prevent counter steering.

In a more preferred embodiment, the support portion may be located as close as possible to the centre line of the axle group. The ideal position of the coupling, in terms of preventing counter steering and the limitation of offtracking of following vehicles, is directly on the centre line.

15 In a preferred embodiment, the carrying means may be containment for liquid, a loading bin for micro or macro-particulate matter or other similar container for bulk materials. Thus, the invention may be applicable for the transport of a plethora of materials and general freight. The transport of liquid, however, offers a particular difficulty for conventional semi-trailers, because of the high concentration of loading that liquid provides. Thus, the invention may provide a S: unique advantage over conventional road trains in its solution of this problem.

In a more preferred embodiment, in the case of the carrying means being a liquid containment, the cross-sectional shape of the containment may be elliptical.

Conventional liquid containment are cylindrical tanks, and thus have a circular 25 cross-section. The resistance of a semi-trailer to overturning is dependent on several factors, a significant one being the height of the centre of gravity. By using an elliptical shape, the centre of gravity is lowered, markedly increasing the semi-trailers ability to resist an applied rolling moment.

In a preferred embodiment, the coupling means may be ball race configuration suited for coupling with a turntable located on the preceding vehicle.

In a preferred embodiment, the support portion may be a turntable suited for connection to a ball race configuration located on the following trailer.

In a further aspect of the invention, there is provided a road train for transporting bulk materials including a combination of at least three semi-trailers wherein the combination is a single roll coupled unit.

In a preferred embodiment, each of the triple axle groups has an axle to axle spacing of 1,500 mm. The normal arrangement uses an axle spacing of 1,350 mm. By using 1,500 mm, and complying with the 9.2 metre minimum axle group spacing, an extra triple axle group can be included within the maximum 53.5 metre overall length. A Triple Road Train typically has 6 triple axle groups, plus an axle group associated with the prime mover. The AB-Quad Road Train uses 6 triple axle groups, plus the prime mover. The present invention may use 7 triple axle groups plus the prime mover, using a 1,500 mm spacing. If a prime mover having a triple axle group is chosen, the GCM provide by the invention may be 194 tonnes, substantially higher than the GCM of 163.5 tonnes of the AB-Quad Road Train.

In a preferred embodiment, the road train consists of three trailer support S: 20 vehicles and 4 trailers.

o 0 00 In a preferred embodiment, the entire length of the road train is less than or equal to 53.5 metres.

Brief Description of the Drawings .:or, It will be convenient to further describe the present invention with respect to the accompanying drawings which illustrate possible arrangements of the invention.

Other arrangements of the invention are possible, and consequently the 00 0 0f 00 -11 particularity of the accompanying drawings is not to be understood as superseding the generality of the preceding description of the invention.

Figure 1 is a side elevation view of the trailer support vehicle, according to one aspect of the present invention; Figure 2 is a side elevation view of the improved semi-trailer, according to another aspect of the present invention; and Figure 3 is a side elevation view of the road train, according to a further aspect of the present invention.

Best Mode(s) for Carrying Out the Invention Figure 1 shows the trailer support vehicle 1, in this case an improved converter dolly, for linking two semi-trailers in a road train combination. The improved converter dolly 1 includes a turntable 3 to which a ball race (not shown) of a semi-trailer (not shown) engages. Directly beneath the turntable is located a triple axle group 4 which, when the improved converter dolly 1 is engaged with the semi-trailer (not shown), provides the forward support for the semi-trailer (not shown). On the forward portion of the improved converter dolly 1 is positioned a Shball race 5 which engages a turntable (not shown) of a preceding semi-trailer (not shown) or a prime mover (not shown).

The forward and rear portions of the improved converter dolly are connected S 20 through a gooseneck shaped projection 2. The combination of the ball race/turntable coupling to the preceding and following vehicle, and the rigid *o connection effected through the goose-neck projection 2 ensure that a rolling moment applied to either the preceding or following vehicles are transferred through the improved converter dolly 1 to the other vehicles in the combination.

25 Each member of a combination has a resistance to overturning. In conventional combinations, using conventional converter dollies, if a rolling moment exceeding *o this resistance is applied to such an element, then the member, say a semitrailer, will roll causing the entire combination to crash. However, using the -12improved converter dolly 1, such a rolling moment can be distributed throughout the combination, and thus the resistance to overturning the entire combination must be overcome before a similar accident can occur, markedly increasing the factor of safety against crashing of the combination.

To further assist in the spreading of load against a pavement or bridge, and to increase the distribution of the carrying load, the spacing between the centreline of each axle 4a is increased to 1500 mm, as compared to the conventional 1350 mm for conventional converter dollies.

The improved converter dolly 1, because of the rigid gooseneck projection 2 provides further advantage in establishing a loading platform 6 onto which additional loads may be mounted. Thus, on the return leg of a delivery run, whereas conventional combination are generally empty, and thus earning no revenue, use of the improved converter dolly 1 allows for a small additional payload to be mounted, offsetting the losses in the return leg. The type of loads and freight the platform 6 can accommodate vary considerably, and can include liquid tanks, loading bins for particulate material or specific loads such as copper cathode 7.

Another advantage of the improved converter dolly 1 is the position of the icoupling with the preceding semi-trailer (not shown). With conventional dollies, the coupling is through a draw bar to the rear of the preceding semi-trailer (not shown). In this orientation, as the preceding semi-trailer turns, the following vehicles are not urged to turn until the preceding semi-trailer has fully turned.

Because the improved converter dolly 1 couples forward of the rear axle of the preceding semi-trailer, the following vehicles are urged to turn much sooner in the curve, aiding steering considerably, as demonstrated by an improved performance for low-speed offtracking of a combination using the improved converter dolly 1.

Figure 2 shows a semi-trailer 8 which may be used with or without the improved converter dolly 1. In this case, the semi-trailer 8 has been adapted to carry liquid freight and thus displays a liquid carrying tank 12. To ensure compatibility with -13conventional combinations, the semi-trailer 8 has a ball race coupling 11 in the forward portion for coupling to a conventional dolly or a prime mover. In the rear portion is also located a turntable 10, for coupling to a following semi-trailer (not shown). However, the semi-trailer 8 of the invention includes specific features providing distinct advantages over the conventional type. In the first instance, the liquid carrying tank of conventional design is circular in cross-section. In the semi-trailer 8 of the invention, the liquid carrying tank is elliptical. The resistance to rolling moment of a vehicle is inversely proportional to the height of the centre of gravity. In a conventional semi-trailer, using a circular tank, the centre of gravity 12a is high. Using conventional methods, to reduce the height of the centre of gravity 12a, it would be necessary to reduce the clearance under the semi-trailer 8. This clearance, however, is strictly controlled by statutory and regulatory standards, and thus, the minimum permissible clearance is generally designed into the semi-trailer 8. In the semi-trailer 8 of the invention, by using an elliptical tank 12, the centre of gravity 12b is considerably lower, and thus, without making any restrictions on function, and maintaining the regulatory standards, the semi-trailer 8 has an enhanced rolling resistance as compared to conventional design.

In addition to the advantages of the semi-trailer 8 when used with conventional combinations, the semi-trailer 8 of the invention, when used with the improved converter dolly 1 displays further advantages. In accordance with the concept of transferring a rolling moment between members of a combination, the coupling means 10, 11 are, so-called, B-type couplings, and therefore designed to transfer such a moment. Another important advantage of the semi-trailer 8, when used with the improved converter dolly 1, is the position of the rear axle group 9. A conventional semi-trailer used for coupling with a following semi-trailer must have S. the rear axle group directly under the coupling of the following semi-trailer, as the axle group must resist a substantial vertical force through supporting the 3 following semi-trailer. With the improved converter dolly 1, the following semi- 30 trailer is not directly coupled to the preceding semi-trailer 8, and thus, the rear axle group does not have a substantial vertical load to support. Thus, the rear axle group 9 can be positioned partially underneath the semi-trailer 8, and assist -14further by directly supporting this load. Further, by increasing the axle centreline spacing 9a from 1350 mm to 1500 mm, the rear axle group can further assist in supporting the load.

Figure 3 shows a quad road train 14 having B-Type couplings between all members 1, 8, 13 of the combination. The quad road train 14 includes a prime mover 13, in this case a prime mover 13 having a triple axle group 13a, four liquid carrying semi-trailers 8 and three improved converter dollies 1, coupling the semi-trailers 8. In this form, the entire quad road train 14 is considered a single roll coupled unit unlike a Triple Road Train (not shown) and an AB-Quad Road Train (not shown), each of which are considered to be three roll coupled units. It follows that, in this combination, the quad road train 14 has superior roll moment resistance to the prior art. Also, in this orientation, a total of 8 triple axle groups are incorporated, each having an allowable maximum loading of 23.5 tonnes, higher than the Triple Road Train (not shown) having 6 triple axle groups and the AB-Quad Road Train (not shown) having 7 triple axle groups. Thus, the quad road train 14 of the invention has a maximum GCM of 194 tonnes as compared to the Triple Road Train of 140 tonnes and the AB-Quad Road Train having 163.5 tonnes.

It is important to emphasize that the quad road train 14 remains within the 0O 20 regulatory overall length limit 15 of 53.5 metres.

Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention.

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Claims (30)

1. A semi-trailer for transporting bulk materials including a containment means for containing bulk materials and a first coupling portion for coupling with a preceding vehicle, each provided on a forward portion of the semi-trailer, and an axle group having a forward-most and a rear-most axle and a support portion for connecting to a following vehicle, each provided on a rear portion of the semi-trailer, wherein the support portion is positioned above and forward of the rear-most axle of said axle group and an axle centre of the axle group is located directly beneath the containment means and adjacent a rear end of the containment means such that the axle group provides a reaction force to support the containment means.

2. The semi-trailer according to claim 1 wherein the support portion is located near a vertical axis of the axle centre.

3. The semi-trailer according to claims 1 or 2 wherein the support portion is o 15 located directly above the vertical axis of the axle centre. S4. The semi-trailer according to any one of claims 1 to 3 wherein the containment means includes any one, or a combination, of a liquid storage container, a loading bin for macro-particulate material or a loading bin for micro-particulate material. oleo 20 5. The semi-trailer according to claim 4 wherein the liquid storage container is substantially elliptically prismatic in shape. The semi-trailer according to any one of claims 1 to 5 wherein the first ooooo coupling portion includes a ball race configuration adapted to engage a turntable.

7. The semi-trailer according to any one of claims 1 to 6 wherein the Support portion includes a turntable adapted to engage a ball race configuration. -16-

8. The semi-trailer according to any one of claims 1 to 6 wherein the support portion includes a fully rotatable tow ball.

9. The semi-trailer according to any one of claims 1 to 8 wherein the following vehicle is a converter dolly.

10.The semi-trailer according to any one of claims 1 to 9 wherein the preceding vehicle is a converter dolly.

11.The semi-trailer according to any one of claims 1 to 10 wherein the axle group includes three axles.

12.The semi-trailer according to any one of claims 1 to 11 wherein an axle spacing of the axle group is at least 1,350 mm.

13.The semi-trailer according to any one of claims 1 to 12 wherein the axle spacing of the axle group is 1,500 mm.

14.A trailer support vehicle and semi-trailer combination, the trailer support vehicle for providing an indirect connection from a preceding vehicle to a following semi-trailer according to any one of claims 1 to 13, said trailer support vehicle including a support portion for supporting the following semi- trailer, a plurality of axles having an axle centre, said axle centre located ••directly below the support portion, a first coupling means for coupling the trailer support vehicle to the preceding vehicle and a projection means 20 extending from the support portion to the first coupling means.

15.The combination according to claim 14 wherein the support portion of the trailer support vehicle includes a second coupling means for coupling to the following semi-trailer.

16.The combination according to claim 14 or 15 wherein the first coupling means of the trailer support vehicle incudes a ball race configuration adapted to engage a turntable. -17-

17.The combination according to claim 15 or 16 wherein the second coupling means includes a turntable adapted to engage a ball race configuration.

18.The combination according to claim 15 or 16 wherein the second coupling means includes a fully rotatable specialized tow ball.

19.The combination according to any one of claims 15 to 18 wherein the plurality of axles of the trailer support vehicle is at least three axles. combination according to any one of claims 14 to 19 wherein the distance from a leading axle to a rear axle of the plurality of axles of the trailer support vehicle is at least 1350 mm.

21.The combination according to any one of claims 14 to 20 wherein the distance from a leading axle to a rear axle of the plurality of axles of the trailer support vehicle is 1500 mm.

22.The combination according to any one of claims 14 to 21 wherein the projection means is a stiff member integrally connected to the support portion and the first coupling means of the trailer support vehicle.

23.The combination according to any one of claims 14 to 22 wherein the support means and the coupling means of the trailer support vehicle are demountable .from the projection means thereof. S S

24.The combination according to any one of claims 14 to 23 wherein the support SSSS 20 means is rearwardly and downwardly spaced from the first coupling means. combination according to claim 24 wherein the projecting means is goose neck shaped.

26.The combination according to any one of claims 14 to 25 wherein the trailer support vehicle is a goose neck shaped converter dolly. -18-

27.The combination according to any one of claims 14 to 26 further including carrying means for transporting articles.

28.The combination according to claim 27 wherein the carrying means is a platform upon which articles may be placed.

29.The combination according to claim 27 or 28 wherein the carrying means is located adjacent the first coupling means of the trailer support vehicle. road train comprising a prime mover, four semi-trailers according to any one of claims 1 to 13, and three trailer support vehicles.

31.The road train according to claim 30 wherein the prime mover is a triple drive prime mover.

32.The road train according to claim 30 wherein the prime mover is a bogie drive prime mover.

33.The road train according to any one of claims 30 to 32 wherein the trailer support vehicles are arranged between the semi-trailers so as to provide combinations according to any one of claims 14 to 29. a,.o

34.The road train according to any one of claims 30 to 33 wherein the road train has an overall length not exceeding 53.5 m. road train according to any one of claims 30 to 34 wherein the road train has a gross combination mass not less than 194 tonnes. 20 36.A semi-trailer substantially as hereinbefore described with reference to ooooI Figures 2 and 3.

37.A trailer support vehicle and semi-trailer combination substantially as hereinbefore described with reference to Figures 1 to 3. 19-

38.A road train substantially as hereinbefore described with reference to Figures 1 to 3. Dated this Tenth day of October 2005. Asset Kinetics Pty Ltd Wray Associates Perth, Western Australia Patent Attorneys for the Applicant ^4