The present invention relates to road-trailer aerodynamic apparatus, including an air deflection device and a rear air deflection fairing, both separately and in combination.

Background

According to the World Shipping Council, 60 percent of global trade, by value, is serviced by the container industry, and ISO shipping containers are a well-known container arrangement that come in a range of sizes to facilitate their respective shipment load volumes.

It is common to observe smaller containers, generally 20’ ISO containers, being transported on standard size semi-trailers. In such cases, the container is located so that there is a large gap between the rear of the tractor unit cab and the front of the container. This positioning is mandated by regulations which are based on such parameters as axle loading I weight distribution and turning radius. This creates a problem. The void between the rear of the cab of the tractor unit and the front of the container creates turbulence and pressure drag, and this results in increased fuel burn. Energy consumption is by far the biggest source of human-caused greenhouse gas emissions, responsible for 73% worldwide. A major contribution to this from the energy sector, along with electricity and heat, is transportation.

Summary

According to one aspect of the present invention, there is provided a closed air deflection device securable to an ISO road-freight trailer, the device forming a generally box shape having in use a front, a back, two sides thereinbetween and a top and bottom thereinbetween, the device being between 2.4m and 2.6m wide, being between 2.5m and 2.9m high, and having a base between 2m and 4.5m long, and having;

(i) an optional convex facia extending across at least part of the front of the device; and (ii) two front twist-lock castings on the bottom of the front of the device, and at least two other locking mechanisms on the bottom of the device distal to the front of the device.

According to another aspect of the present invention, there is provided a method of reducing the aerodynamic drag of a ISO road-freight trailer transporting an ISO roadfreight container thereon, comprising the step of:

- locating an air deflection device as defined herein on the ISO road-freight trailer in front of the ISO container.

According to another aspect of the present invention, there is provided a tractortrailer compound vehicle comprising a front tractor, an ISO road-freight trailer, an ISO load on the trailer, and an air deflection device as defined herein, optionally comprising a skeletal ISO road-freight trailer.

According to another aspect of the present invention, there is provided a rear air deflection fairing for an ISO road-freight trailer, the device having two vertical trapezoidal side portions and a horizontal trapezoidal top portion connecting the two side portions, the side portions being between 2.5m and 2.9m high, and the top portion being between 2.4m and 2.6m wide, wherein the fairing includes attachments adapted to secure the fairing to the rear of a ISO road-freight container, and wherein the side portions and top portions form a trapezoidal prism shape.

According to another aspect of the present invention, there is provided a method of reducing the aerodynamic drag of a ISO road-freight trailer transporting an ISO roadfreight container thereon, comprising the step of:

- fixing a rear air deflection fairing as defined herein onto the rear of the ISO container on the ISO road-freight trailer.

According to another aspect of the present invention, there is provided a tractortrailer compound vehicle comprising a front tractor, an ISO road-freight trailer, an ISO load on the trailer, and a rear air deflection fairing as defined herein, optionally comprising a skeletal ISO road-freight trailer. According to another aspect of the present invention, there is provided a tractortrailer compound vehicle comprising a front tractor, an ISO road-freight trailer, an ISO load on the trailer, and an air deflection device as defined herein, and a rear air deflection fairing as defined herein.

According to another aspect of the present invention, there is provided a method of reducing the aerodynamic drag of a ISO road-freight trailer transporting an ISO roadfreight container thereon, comprising the steps of:

- locating an air deflection device as defined herein on the ISO road-freight trailer in front of the ISO container.

- fixing a rear air deflection fairing as defined herein onto the rear of the ISO container on the ISO road-freight trailer.

The present invention seeks to minimise the pressure drag effect created by the transportation position of containers on trailers and semi-trailers relative to the rear face of the cab of the tractor unit towing the trailer, and improvements to aerodynamic flow at the rear of trailers and semi-trailers transporting containers.

Description of the drawings

Figure 1 is a side view of a tractor-skeletal trailer carrying a 20’ ISO container in a transportation position;

Figures 2 -4 are perspective, side and bottom views respectively of an air deflection device according to one embodiment of the present invention;

Figure 5 is a side view of a tractor-skeletal trailer in a pre-transportation loading/unloading position;

Figure 6 is a side view of the tractor-skeletal trailer of Figure 5 carrying a 20’ ISO container.

Figure 7 is a perspective view of the device of Figures 2-4 carried by a forklift truck;

Figure 8 is a side view of Figure 6 loading the air deflection device of Figure 2; Figure 9 is a side view of Figure 8 with a loaded and secured air deflection device;

Figure 10 is partial view of Figure 9;

Figure 11 is an enlarged portion of Figure 10;

Figures 12-13 are perspective and rear views respectively of a rear air deflection fairing according to another embodiment of the present invention;

Figure 14 is a perspective view of the rear air deflection fairing of Figures 12-13 on a forklift truck;

Figure 15 is a perspective view of the rear air deflection fairing of Figures 12-13 located on the rear of an ISO container;

Figure 15A is an enlarged portion of Figure 15;

Figure 16 is a rear perspective view of a tractor-trailer compound vehicle according to another embodiment of the present invention, comprising a front tractor, an ISO road-freight trailer, an air deflection device, and a rear air deflection device; and

Figure 17 is a view of Figure 16 with the skeletal trailer in a transportation position.

Detailed description of the drawings

The design of articulated vehicle combinations used for the transportation of containers is inefficient because the position of the containers on semi-trailers, as well as the characteristics of those containers, generate significant, avoidable pressure and friction drag. The impact of drag is higher fuel burn and associated production of greenhouse gases.

It is common to observe smaller containers, generally 20’ (6m) ISO containers, being transported on standard size semi-trailers. In such cases, the container is located so that there is a large gap between the rear of the cab of the tractor unit and the front of the container. This positioning is mandated by regulations which are based on such parameters as axle loading / weight distribution and turning radius.

This creates a problem. The void between the rear of the cab of the tractor unit and the front of the container creates turbulence and pressure drag, and this results in increased fuel burn. Transportation is a significant source of greenhouse gas emissions.

According to one embodiment of the present invention, there is provided a closed air deflection device securable to an ISO road-freight trailer, the device forming a generally box shape having in use a front, a back, two sides thereinbetween and a top and bottom thereinbetween, the device being between 2.4m and 2.6m wide, being between 2.5m and 2.9m high, and having a base between 2m and 4.5m long, and having;

(i) an optional convex facia extending across at least a part of the front of the device; and

(ii) two front twist-lock castings on the bottom of the front of the device, and at least two other locking mechanisms on the bottom of the device distal to the front of the device.

Aerodynamic studies have revealed that every 300mm reduction in the gap between the rear of the tractor unit cab and the front of the container on its trailer will result in the diminution of pressure drag by 2.6%. A 1% decrease in pressure drag roughly equates to a 0.5% decrease in fuel burn.

The majority of European vehicles transporting 20ft containers have a gap of approximately 3.8 metres between the rear of the cab and the front of the container. This equates to 32.5% pressure drag, which, if eliminated, provides a reduced fuel burn of 16.25%.

The term “closed” as used here refers to the device not intending to have an opening or be otherwise openable. This includes but is not limited to a sealed device, not necessarily hermetically sealed, or otherwise formed as an enclosure not intending to be filled (other than with air). The term “ISO road-freight trailer” as used herein relates to the drawn portion of an articulated tractor-trailer combination, able to transport ISO containers on a road, and complying with local highway regulations. The term includes ‘fixed-bed’ trailers and sliding or solid state skeletal trailers. Such trailers generally have a series of parallel twist lock mechanisms on each side of the trailer longitudinal axis, for securing corner castings of an ISO container thereon or thereto. The trailer may have multiple axles, typically two, three or four axles, each with single or dual wheels. Optionally, one or more of the axles can be lift axles, able to lift their wheels off the road surface when not required. Some trailers include a tipping mechanism to allow for unloading containers filled with loose material.

The terms “front” and “back” and “side” and “top” and “bottom” of the air deflection device relate to the location of the relative faces of the device when in position of the device on an ISO road-freight trailer The ‘front’ of a tractor-trailer combination is the cab of the tractor, and the front of a trailer is that end or portion to be connected to the tractor via the kingpin. A tractor or tractor cab can include an integral fairing on its sides and top, and any reference to a tractor or a cab herein can include such a fairing

The term “generally box shape" as used herein relates to a general cuboid shape, having flat and parallel sides, a flat top and bottom, preferably a flat back, which can also be open ended, designed to be located close to and parallel to the front of an ISO container. The front portion may be flat or shaped, which shape still provides a generally box shape overall with the other faces of the device.

The bottom of the air deflection device may include an integral or external chassis or base or frame or frame portions, adapted to support the air deflection device, and to provide location of the twist-lock castings, additionally the bottom or underside of the air deflection device may include a tunnel so as to allow the device to be compatible with wither straight frame chassis or goose neck chassis.

ISO containers are well known in the art, and are a standardised reusable steel box, generally used for storage and movement of materials and products within a freight transport system, including by road-freight. ISO containers are manufactured according to the specifications outlined by the International Organisation for Standardisation. The most common ISO container known and used, including in metric-using countries, is termed a “40ft” ISO container, being 40 feet long. This measurement is typically and most easily considered to be approximately 12m or 12.2m in metric units.

Another very common ISO container is the “20ft” ISO container, sometimes also termed a “twenty foot equivalent unit” or “TEU”, being 20-foot long. In metric units, this is typically considered as being 6m or 6.1m long.

Other ISO containers are known in the art, in particular a 30ft container being thirty- foot-long, approximately 9.1m long.

The dimensions of an ISO container are also generally measured and used in the art used in “feet”, rather than metric measurements. Thus, the typical ISO container is generally regarded to be 8ft wide, and 8.5ft high. These measurements can be stated in metric units as approximately 2.4m wide and 2.6m high.

The present invention also relates to use with ‘high cube’ ISO containers which are 9ft 6” (2890mm) high.

Thus, the closed air deflection device can be between 2.5m and 2.9m high, optionally 2890mm high. More commonly, the closed air deflection device is approximately 2.6m high.

Meanwhile, most highway regulations allow a maximum vehicle width of 2555mm for dry containers, and 2600mm for refrigerated/insulated containers. Thus, the air deflection device of the present invention can have a width in the range 2440mmm to 2600mm, such as 2600mm wide. More commonly, the closed air deflection device is approximately 2.55m or 2555mm wide.

The reference to metric dimensions to define the width, height and length of the device allow for some approximation, following the usual use of imperial units in relation to ISO container dimensions. The present application is not limited to the exact definition of any dimension listed, but allows for some approximation that can be reasonably foreseen in relation to the measurements of an ISO container.

According to one embodiment of the present invention, the air deflection device is 2.6m high, 2.55m wide, and at least 3.8m long.

Optionally, the air deflection device is 2585mm high, 2550mm wide, and has a base being 3910mm long. This air deflection device can also be termed the Nesflector IVEAS.

As discussed in more detail hereinafter, in particular in relation to the accompanying drawings, 3.8-3.9m metres is the approximate distance between the correct position of a loaded 20ft ISO container on a skeletal trailer, and the back of a cab of a tractor carrying said trailer. This distance is currently the most common gap or ‘void’ in relation to the transporting of 20ft ISO containers, and thus forms the most expected use of the air deflection device of the present invention when used with current design of ISO road-freight trailers, in particular skeletal ISO road-freight trailers in at least the countries of Europe. The construction and use regulations influencing road articulated combinations in other countries vary, and consequently, the distance between the rear of the cab of the tractor and the front face of the ISO shipping container may be different or greater. The skilled reader can see that other gaps or voids of shorter or longer dimension occur when different containers are used, or different loads are carried, or different trailers are used. Skeletal trailers allow a user to vary the length of the trailer in a manner known in the art, although the positioning of a load thereon is often still wholly or substantially dictated by road regulations concerning correct trailer loading through the axle or axles of the trailer.

The present invention is also useable in relation to other types of containers, including bulk and tank containers having an external structure which offers lifting and securing corner castings at the positions consistent with standard ISO shipping container designs. Such containers are considered to be covered by the term “ISO container” as used herein.

According to an alternative embodiment, the air deflection device is 2.6m high, 2.55m wide, and approximately 2.2m long. The device of the present invention may include a convex facia extending across at least part of the front of the device. The facia may have any suitable curvature, generally extending from each side of the face, and forming a forward curvature in use, able to assist deflection of airflow that would hit the front of the device during transportation, in particular during cornering of a tractor-trailer that exposes the front of the device directly to oncoming airflow. The design and scale of the front facia may correspond to turning circles which are measured in distance from the kingpin used to couple a semi-trailer to the tractor unit.

In one embodiment, the front of the device comprises a convex facia portion extending outwardly front the front, and extending from the top of the front to an intermediate depth of the front, and a flat portion extending from the intermediate depth to the base of the front.

The flat portion of the front, extending from its base or bottom, can be used to allow access to the couplings of the trailer.

According to another embodiment of the present invention, the air deflection device having a front convex facia as described herein can have a length of the top of the device and the extending convex facia in the range 4.2m to 4.3m, such as 4240mm and a length of the bottom of the device to the flat portion of the front is in the range 3.9m to 4m, such as 3910mm.

The air deflection device of the present invention may be formed of any suitable material or combination of same, such as metal, in particular steel, and plastics. Such materials include inflatable materials, to provide a wholly or partly inflatable air deflection device, fixable to ISO fixing points. The air deflection device may be formed to achieve low weight impact where maximising cargo tonnage is crucial. The air-deflection device is intended to have a relatively smooth outer surface, and may include a coating to assist reduced aerodynamic drag.

Twist-lock castings are known in the art, and generally comprise a cuboid structure, having apertures able to engage with ‘twist-lock mechanisms’ located on the trailer. Twist-lock mechanisms are also well known in the art, and generally move between an open position, with the neck and head of the lock located within a housing attached to specific points or portions of the trailer, and a locked position where the neck and head of the lock are exposed above a surface of the twist-lock housing, and the head is twisted by a handle to engage with a portion or surface of the twistlock corner casting on the ISO container, so as to effectively lock the trailer and ISO container together, especially during transportation.

The use and action of twist-lock mechanisms is well known in the art, and the location of the twist-lock mechanisms on a trailer useable with the present invention is the same arrangement as currently known in the art. Typically, an ISO roadfreight trailer has two twist-lock mechanisms at the front of the trailer nearest to the cab or tractor in use, followed by regular spacing of parallel pairs of twist-lock mechanisms extending along the length of the trailer away from the cab or tractor, and in positions deliberately suited to match the positions of the twist-lock corner castings on ISO containers. ISO road-freight trailers are designed to be able to carry at least either a 20ft ISO container or a 40ft ISO container, and possibly also to carry a 30ft ISO container.

The air deflection device includes at least two other locking mechanism on the bottom of the device distal to the front of the device.

According to an embodiment of the present invention, the locking mechanism includes an extendible locking bolt at or near the bottom of the back of the device, able to engage with an ISO container in use, in particular, able to engage with a corner casting of an ISO container.

Typically, the other locking mechanisms of the air deflection device comprise two locking bolts and housings therefor, one on each side of the back of the device. The or each locking bolt is typically moveable between a retracted position located within suitable housing being a part of the bottom, or part of the chassis, of the air deflection device, and extended position able to engage with an complementary- positioned corner casting of the ISO container, and optionally to be fixed therewith. In this way, the bottom of the back of the device can be secured to the ISO container in use on the trailer, providing extra securement of the air deflection device on the ISO road-freight trailer.

Optionally, the air deflection device includes a plurality of forklift lifting slots.

According to another embodiment of the present invention the air deflection device includes a tunnel or gooseneck in portion along the bottom of the device. This facilitates making the air deflection device compatible with either standard skeletal trailers or with ‘gooseneck’ trailers. Gooseneck trailers can lower the overall combined height of the combination of tractor unit, semi-trailer and ISO shipping container, as the gooseneck portion of the semi-trailer becomes recessed into the tunnel provided on the underside of the air deflection device.

According to another embodiment of the present invention, there is provided a method of reducing the aerodynamic drag of an ISO road-freight trailer transporting an ISO road-freight container thereon, comprising the step of:

- locating an air deflection device as defined herein on the ISO road-freight trailer in front of the ISO container.

The air deflection device may be located on the ISO road-freight trailer using a suitable mechanism or vehicle. Optionally, it is located using a forklift truck, and hence the air deflection device can include plurality or two elongate slots at or near its bottom, for location of the forks of a forklift truck thereinto.

The method of the present invention includes securing the air deflection device to the ISO road-freight trailer through the twist-lock castings, by operation of the twist-lock mechanisms on the ISO road-freight trailer in a manner as described herein above. Typically securement is achieved by movement of a head or head portion of the twist-lock mechanism in through an aperture in the twist-lock corner castings, and rotation by approximately 90° so as to form an overlap of the head with the twist-lock casting in use. Unlocking of the twist-lock mechanism is typically by the reverse actions, so as to disengage an overlapping head of the twist-lock mechanism with the twist-lock corner casting, and relocation of the twist-lock mechanism within a housing below the location of the twist-lock corner castings. Additionally, there are other variations of twist lock mechanisms which operate in a screw-like manner to achieve the same result as the handle operated twist lock variety, and these are included in the scope of the present invention.

According to one embodiment of the present invention, there is provided a method of reducing the aerodynamic drag of an ISO road-freight trailer transporting an ISO road-freight container thereon, comprising the steps of:

- providing an air deflection device as defined herein prior to transportation of the ISO road-freight container;

- locating an air deflection device on the ISO road-freight trailer in front of the ISO container;

- removing the air deflection device after transportation of the ISO road-freight container.

In a further embodiment of the present invention, the ISO road-freight container for use with the present invention is a 20ft (6m) ISO container.

According to another embodiment of the present invention, there is provided a tractor-trailer compound vehicle comprising a front tractor, an ISO road-freight trailer, an ISO load on the trailer, and an air deflection device as defined herein between the load and the tractor.

Optionally, the tractor-trailer compound vehicle has a trailer which is a skeletal ISO road-freight trailer. Skeletal trailers are described elsewhere herein. The operations of extending and contracting the length of an extendable trailer, in particular a sliding or skeletal trailer, are well known in the art, and are not further described herein.

Optionally, the tractor-trailer compound vehicle has a load being one of: a 40ft, 30ft, 20ft, combination of two 20ft, or a bulk or a tank, ISO container.

According to another aspect of the present invention, there is provided a rear air deflection fairing for an ISO road-freight trailer, the device having two vertical trapezoidal side portions and a horizontal trapezoidal top portion connecting the two side portions, the side portions being between 2.5m and 2.9m high, and the top portion being between 2.4m to 2.6m wide, wherein the fairing includes attachments adapted to secure the fairing to the rear of a ISO road-freight container, and wherein the side portions and top portions form a trapezoidal prism shape.

Aerodynamic studies have revealed that such a fairing shape at the rear of the container on a trailer equates to a 6.5% decrease in fuel burn.

The term “trapezoidal” as used herein generally defines a quadrilateral having one pair of parallel sides, and optionally having the side’s thereinbetween being at one or two angles, not forming a square or rectangle. Optionally, the horizontal trapezoidal top portion forms a regular trapezium, and the two vertical trapezoidal side portions have parallel sides, one orthogonal side thereinbetween, typically forming a bottom side, and an angled other side adapted to match the sides of the top portion.

As mentioned hereinbefore, the present invention relates to use with ‘high cube’ ISO containers which are 9ft 6” (2890mm) high. More commonly, the rear air deflection fairing is approximately 2.6m high.

Meanwhile, most highway regulations allow a maximum vehicle width of 2555mm for dry containers, and 2600mm for refrigerated/insulated containers. Thus, the rear deflection fairing of the present invention can have a width in the range 2440mmm to 2600mm wide. More commonly, the rear air deflection fairing is approximately 2440mm wide.

According to one embodiment of the present invention, the rear air deflection fairing is 2.6m high, 2.44m wide, and less than 1m long.

Optionally, the rear air deflection fairing is 2580mm high, 2440mm wide, and 900mm long.

Optionally, the rear air deflection fairing comprises one or more struts between the side portions below the top portion. The struts provide further rigidity to the fairing. Optionally, the rear air deflection fairing further comprises ISO twist lock attachments at each end of the side portions proximal to an ISO road-freight container in use. The attachments include pins, hooks, studs, spigots and the like, able to engage with the rearmost corner castings of an ISO container.

Optionally, the rear air deflection fairing further comprises forklift lifting ports under the top portion or any other suitable position. The ports may be formed by suitable slots or apertures in a separate frame, or be integral with the top portion.

The rear air deflection fairing of the present invention may be formed from any suitable material or combination of same, such as metal, in particular steel, and plastics. The fairing is intended to have a relatively smooth outer surface, and may include a coating to assist reduced aerodynamic drag.

According to another embodiment of the present invention, there is provided a method of reducing the aerodynamic drag of an ISO road-freight trailer transporting an ISO road-freight container thereon, comprising the step of:

- fixing a rear air deflection fairing as defined herein onto the rear of the ISO container on the ISO road-freight trailer.

The fairing may be positioned towards an ISO container using a suitable mechanism or vehicle. Optionally, it is located using a forklift truck, and the fairing includes two elongate slots at or near its top, for location of the forks of a forklift truck thereinto, able to lift the fairing from a ground surface to a position aligned with the rear of an ISO container, and to locate engaging parts of the fairing onto corner castings on the rear of an ISO container, such as hooks or pins on the fairing being slotted into the top apertures of corner castings. Suitable locking pins can engage and be locked with lower corner castings of the ISO container.

The present invention extends to a tractor-trailer compound vehicle comprising a front tractor, an ISO road-freight trailer, an ISO load, and a rear air deflection device as defined herein.

Optionally, the trailer is a skeletal ISO road-freight trailer, discussed elsewhere herein. Optionally, the load is one of: a 40ft, 30ft, 20ft, combination of two 20ft, or a bulk or a tank, ISO container, discussed elsewhere herein.

The present invention also extends to a tractor-trailer compound vehicle comprising a front tractor, an ISO road-freight trailer, an ISO load, and an air deflection device as defined herein, and a rear air deflection device as defined herein.

Aerodynamic studies have revealed that for transporting a 20ft ISO container, normally leaving a gap of approximately 3.8 metres between the rear of the cab and the front of the container, the use of the combination of an air deflection device as defined herein, and a rear air deflection device as defined herein, provides a reduced fuel burn of more than 20%, such more than 22%, such as 22.75%.

Typical European manufactured HGVs consume approximately 30 - 35 litres (vehicle efficiency is continuously improving) of diesel per 100km travelled. At 35 litres per 100km travelled, this equates to 7.9625 litres of diesel and 18.31 kilos of CO2 per 100km travelled. These estimates are expected to be significantly greater for vehicles manufactured in North America, as they generally have a higher fuel burn due to structural and design differences from those vehicles used across Europe. The skilled reader can see that a possible reduced fuel burn of 22.75% from these figures, or higher fuel consumptions figures is significant.

Optionally, the trailer is a skeletal ISO road-freight trailer, discussed elsewhere herein.

Optionally, the load is a 20ft (6m) ISO container on the trailer, discussed elsewhere herein.

According to another embodiment of the present invention, there is provided a method of reducing the aerodynamic drag of an ISO road-freight trailer transporting an ISO road-freight container thereon, comprising the steps of:

- locating an air deflection device as defined herein on the ISO road-freight trailer in front of the ISO container. - fixing a rear air deflection fairing as defined herein onto the rear of the ISO container on the ISO road-freight trailer.

Optionally, the ISO road-freight trailer is an extendible trailer, and the method of reducing the aerodynamic drag of a ISO road-freight trailer transporting an ISO roadfreight container thereon comprising the steps of:

- contracting the trailer from a road use extended position to a contracted position:

- locating a 20ft (6m) ISO road-freight container onto the rear portion of the trailer;

- fixing a rear air deflection fairing as defined herein onto the rear of the ISO container on the ISO road-freight trailer;

- providing an air deflection device as defined herein prior to transportation of the ISO road-freight container;

- locating and securing the air deflection device onto the ISO road-freight trailer in front of the ISO container;

- adjusting the length of the trailer to suit the weight of the ISO container.

Some of the steps described herein may be varying order, and not limited to the sequential order listed.

Referring the accompanying drawings, Figure 1 shows an existing tractor-trailer compound vehicle 2, comprising a front tractor 4 having a cab 6 and cab fairing 7, an ISO road-freight trailer 8 comprising a bed 10 and multi-wheeled axle unit 12, and a 20ft unit (herein after TEU) 14 in an arrangement known in the art.

The TEU 14 is located towards the rear of the trailer 8, and with a position dictated by the known regulatory requirements and highway regulations according to its weight, especially whether the TEU is loaded or unloaded. Such regulations are relevant to an ISO shipping container being laden to the extent that the prevailing legislation requires that the weight is transferred or distributed in accordance with maximum permissible axle loadings. Thus, in Figure 1 , the end of the bed 10 extends beyond the rear of the TEU 14 to position the rear of the TEU over the rear axle unit 12.

Figure 1 shows that there is a gap or void of general length “D” between the back of the cab fairing 7 and the front 18 of the TEU. The length of D is typically about 3.8m or 3.9m. This gap or void creates turbulence and pressure drag, which results in increased fuel burn. As mentioned above, aerodynamic studies have shown that for every 300mm reduction in the gap between the rear of the tractor unit cab and the front of an ISO container will result in the diminution of pressure drag by 2.6%. A 1% decrease in pressure drag roughly equates to a 0.5% decrease in fuel burn.

Figure 2 shows an example of a closed air deflection device 20 according to one embodiment of the present invention. The device 20 forms a general box shape, having in use, a front 22, a back 24, two sides 26 in between the front 22 and back 24, a top 28 and a bottom 30, in between the front 22, back 24 and sides 26. Figures 2-4 also show the front 22 having a first portion 31 up to an intermediate height being generally flat to provide access to tractor connections typically provided from a tractor at such a height, and a second portion 32 above the first portion 31, and having a convex facia extending horizontally and wholly across the front 22 between the sides 26.

The device 20 includes a chassis 34 along the bottom 30. The chassis 34 includes corner castings 36 at each front corner, and a certain distance there behind along the sides of the chassis 34. The positioning of the corner castings 36 is intended to directly match the common or usual positioning of ISO twist-lock attachments located on the bed 10 or next to the bed 10 of the trailer 8, and discussed in more detail hereinafter.

The chassis 34 is arranged to include a tunnel or goose-neck 38 extending longitudinally from the front of the chassis 34 to the rear of the chassis 34 and along the middle of the device 20. The tunnel 34 provides an opportunity to accomplish reducing the overall height of the tractor, trailer, ISO container combination as the gooseneck design of the trailer is permitted to recess into the tunnel provided on the underside of the container and air deflection device 20.

Each side 26 of the device 20 includes a number of slots 39. The slots 39 provide suitable pockets for the handling of the device 20 by a forklift truck as discussed hereinafter. The device 20 may have two small fork slots 39 and two big fork slots 39 to fit the usual fork dimensions of forklift trucks, typically being either 360mm or 250mm wide. The skilled person can see that the device 20 of the present invention can include any arrangement of forklift lifting slots or pockets or other types of slots or apertures, to allow easy handling by complementary machinery.

An ISO container is designed to have a height of 8 feet (imperial units). This is approximately 2.6m, but can be more accurately 2585mm.

An ISO container is intended to have a width of 8 feet and 6 inches in imperial units. This is approximately 2.4m, and more accurately 2440mm. However, most highway regulations allow a maximum vehicle width of 2555mm for dry containers and 2600mm for refrigerated/insulated containers, so that the device 20 of the present invention can be in the range 2440mmm to 2600mm.

The example of the present invention shown in Figures 2-4 has an overall length of the 4240mm between the back of the top to the furthest extent of the convex facia 32. The device 20 has a length of 3910mm between the back of the bottom 30 and front of the flat portion 31 of the front 22.

Optionally, the device 20 can include either further corner castings or similar units or devices at or on its back 24, to assist location and direct securement of a rear air deflection fairing, for the transportation thereof when desired.

Figure 5 shows the tractor-trailer compound vehicle 2, with the front tractor 4 and trailer 8. The trailer 8 in the example of the present invention shown in Figures 5 and 6 is a skeletal or sliding trailer, i.e. a trailer able to vary the length of its bed. Such trailers are well known in the art, and are intended to provide a convenient multi-use trailer that is able to carry both a regular 40ft ISO container, and also to carry shorter loads, in particular 30ft or 20ft ISO containers. This is achieved by contracting or shortening the length of its bed in a manner known in the art, reducing the overall length of the tractor-trailer combination, and thereby reduce some tyre wear and fuel load in a manner known in the art.

Figure 5 shows the tractor-trailer compound vehicle 2 wherein the bed 10 has been contracted to a length less than 40ft. The detail of how a skeletal trailer 8 is moveable between a contracted position as shown in Figure 5 and an expanded or elongated or road transport position as shown in Figure 1 is not described in detail herein.

Figure 6 shows the tractor-trailer compound vehicle 2 with a TEU 14 now located at the rear of the trailer 8, such that the rear face 15 of the TEU is wholly or substantially flush with the rear of the bed 10. In this way, a conventional forklift truck can load a rear air deflection device onto the rear face 15 of the TEU 14 as discussed hereinafter.

Alternatively, the use of a telescopic loader or forklift may negate the need to contract and extent a trailer bed, where telescopic loading of a rear air deflection device as discussed hereinafter does not require the rear face 15 of the TEU to be flush with the end of the bed 10.

The TEU can be loaded onto the trailer 8 by the use of any conventional means, typically a forklift truck in a manner known in the art.

Figure 7 shows a forklift truck 40 lifting the closed air deflection device 20 shown in Figures 2-4 by the use of its forks 41 slotting into suitable slots 39 along one side 26 of the device 20. The forklift truck 40 can then manoeuvre and locate the device 20 in between the TEU 14 and the front tractor 4 and the cab fairing 7, as shown in Figure 8.

Figure 9 shows a tractor-trailer compound vehicle 2 comprising a front tractor 4, an ISO road-freight trailer 8, a load on the trailer being a TEU 14, and a closed air deflection device 20 between the TEU 14 and the front tractor 4. The device 20 fills the space between the rear of the tractor 4 and the front 18 of the TEU 14. In this way, the device 20 minimises the cause of associated pressure drag shown by the gap or space in D in Figure 1 above.

The convex facia 32 provide a convex front face of the device 20 that is complementary to the cab fairing 7, and provides further air deflection, especially when the trailer 8 and the tractor 4 are in non-alignment, such as during cornering or turning or the like. The device 20 can be secured to the trailer 8 by the use of the corner castings 36. The corner castings 36 are wholly or substantially the same as known corner castings located at the corners of ISO containers, such that they are designed to engage with known and complementary twist-lock assemblies that are located on or next to the bed 10 of ISO trailers.

Typically the twist-lock mechanisms comprise a neck and head portion, and a handle locatable below a flat surface. Once a corner casting such as the twist-lock castings 36 of the device 20 are located in complementary alignment with the twist-lock neck and head, use of the handle, or other design variations, allows the user to rotate the head, such that portions of the head are now over surfaces within the corner castings, locking the corner casting and mechanism together. The operation of twistlock mechanisms are well known in the art, and unlocking is achieved by reverse motion of the associated handle or other design variation.

It is a feature of the device 20 to locate its corner castings 36 along the base chassis 34 in line with the positioning of twist-lock assemblies already known in the art, which are already wholly or substantially dictated by the positioning of corner castings on ISO containers. Thus, no adaptation of the trailer or bed is required, to locate and secure the device 20 on an existing ISO tractor-trailer compound vehicle.

Figure 10 shows portions of the device 20 and the front of a TEU 14, partly enlarged in Figure 11 to show a further locking mechanism. Figure 11 shows a bolt 44 able to be housed in the rear of the chassis 34, and extendable once the device 20 is located on the trailer 8, to slot into an aperture of a corner casting 46 of the TEU. In this way, the device 20 can be further secured during transportation, by engagement with the TEU 14 (which is separately secured to the trailer 8 using its corner casting 46 and other corner castings in a manner known in the art).

The skilled person can see that the device 20 avoids the drag caused by the gap or void of distance D shown in Figure 1 above. The skilled person can see that the device 20 can be used in relation to loads on a tractor-trailer compound vehicle other than a TEU, including but not limited to other forms of ISO container, including the known 30ft ISO container and known 40 ISO container. Such other loads can include vehicles carried by road on tractor-trailer compound vehicles, such as tanks and other large vehicles, which have large aerodynamic drag. Thus, the skilled person can see that the device 20 of the present invention can be used for a variety of loads that are required to be positioned some distance from a tractor or tractor cab fairing, and which are relatively unaerodynamic, to achieve the same increased fuel economy as discussed above.

The device can be formed using known and simple materials, with the preferred requirements of having durability and relatively little weight, along with being easy to handle and store. The use of lightweight metals and plastics, and combinations of same, can provide easy forming of a closed device, with a relatively smooth outer surface, to maximise expected aerodynamic efficiency during use. Thus, the device 20 achieves minimal friction drag by itself, and minimal additional weight loading, to the tractor-trailer compound vehicle.

Figures 12 and 13 show a rear air deflection fairing 50 for an ISO road-freight trailer, the fairing 50 having two vertical trapezoidal side portions 52, and a horizontal trapezoidal top portion 54 connecting the two side portions 52. The side portions 52 can be between 2.5m and 2.6m high, and the top portion can be 2.4m wide. By way of example, the fairing 50 can have a height of 2580mm, and a width of 2440mm, which measurements are near to the SI comparison with the imperial measurements of the width and height of an ISO container.

The rear fairing 50 also comprises two struts 56 extending directly between the longest lengths of the side portions 52, and a framework 62 located between the longest sides of the side portions 52 and the shortest side of the top portion 54. The framework 62 includes two slots 64 for location of the forks of a forklift truck, as discussed herein after.

The rear fairing 50 includes lower locking mechanisms being moveable bolts 60, located inside the base of the longest side of each side portion 52, and upper locking mechanisms being pins or hooks 63 located at the top of the longest side of each side portion 52, and at the ends of the longest side of the top portion 54. Optionally, the rear fairing 50 includes a frame or framework 58 forming an inverse “II” along the longest portions of the side portions 52 and top portion 54, to which the lower mechanism 60 and upper pins or hooks 63 can be attached or formed therewith.

Figures 12 and 13 show the arrangement of the side portions 52 and top portion 54 to form a trapezoidal prism shape.

Figure 14 shows a forklift truck 40 locating forks 41 into the slots 64 of the rear fairing 50, so as to lift the rear fairing 50 into a suitable position for locating against the rear 15 of the TEU 14 in a manner shown in Figure 15. The location of the rear fairing 50 can be achieved by the vertical transition of the rear fairing 50 down onto two upper corner castings 70 of the TEU coupling with hook type structures so as to engage the pins 63 therewith, followed by movement of locking bolts 60 of the rear fairing 50 into lower corner castings 72 of the TEU. In this way, the rear fairing 50 is secured to the TEU 14 at its four forward corners.

The rear fairing 50 reduces the area of pressure drag created by the large wake of a travelling tractor-trailer compound vehicle with ISO container, resulting from the bluntness of the backend of the ISO container. The rear fairing 50 forms a type of ‘boat tail’, which has been shown in aerodynamic studies to reduce drag sufficiently to contribute to a 6.5% decrease in fuel burn.

The rear fairing 50 can be attached and secured to the rear of any ISO container, and is shown herein to be easily attachable and detachable when required, in particular through the use of existing corner castings on the ISO container, avoiding the requirement for fabrication of new attachment points on an ISO container.

Figure 16 shows a tractor-trailer compound vehicle 2 comprising a front tractor 4, and ISO road-freight trailer 8, a load being a TEU 14, as well as the air deflection device 20 described hereinbefore, and a rear air deflection fairing 50 described hereinbefore. The combination of both the device 20 and fairing 50 provides possible reduction in fuel burn of the overall combination by over 20%, possibly more than 22%, compared with the arrangement shown in Figure 1.

Figure 17 shows the extension of the bed 10 of the trailer 8 back to a transportation position, in order to position the weight of the TEU 14 in its required loading positioning relative to the axles and wheels of the tractor-trailer compound vehicle 2. Thus, Figure 17 shows the tractor-trailer compound vehicle 2 ready for road transportation. The skilled person can see that each of the device 20 and rear fairing 50 of the present invention can be used separately to achieve fuel burn savings, and that their combined use achieves combined fuel burn savings. Analysis of the present invention indicates a road tractor-trailer that can achieve fuel burn savings of >20%, in particular for non-aerodynamic loads, or loads which must be located on a trailer in an un-aerodynamic position. Such fuel savings are significant.

The skilled person can see the use of either the device 20 or rear fairing 50 with loads other than a TEU, in order to achieve the same advantages and benefits as described herein.