AU713255B3 - A trailer - Google Patents

Description

P/00/012 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE

SPECIFICATION

PETTY PATENT Invention Title: A TRAILER The following statement is a full description of this invention, including the best method of performing it known to me: 1 Document4 2 A TRAILER The present invention relates to a trailer for haulage by a prime mover and in particular to a trailer that has capacity for dual loading of liquids and solids in/on separate areas of the trailer.

Efficient and cost-effective transport of goods requires a transport vehicle to be able to carry payload for a substantial majority of its running time.

Thus, it is desirable that where a transport vehicle carriers a load to a particular delivery destination, that the vehicle be reloaded for return from that destination. This maximises the period in which the transport vehicle is engaged for paid transport and thus minimises the amount of non-payable travel time. Many transport routes allow a transport vehicle to operate in this manner. For example, transport between major cities normally facilitates one load of goods to be transported from one city to the other, while a different load of goods can be transported on return. However, there is less scope for this manner of operation when the delivery destination is a more remote location, or a smaller town or facility, that only requires inward delivery of goods or that does not require inward delivery, but instead only requires outward delivery.

The above difficulty may arise for example, in relation to a timber logging facility, which may have a need to receive only a small variety of goods for operating purposes, and which is also remotely located. Thus, it is unlikely that the transport vehicle which is sent to the logging facility for pick-up of timber products could carry a different load to the facility or to an adjacent destination on the inward journey to the facility. In this particular example, the facility may require some supplies, such as food and equipment that could be carried inwardly by the transport vehicle, but the volume of those supplies would be far exceeded by the volume of timber product to be removed from the facility.

Such a facility may however, require substantial volumes of fuel, generally diesel fuel, but such fuel is required to be transported by a tanker, not a timber trailer. It has therefore been necessary in the past to send an unloaded transport vehicle to the logging facility to pick-up the timber products and to send a filled fuel tanker to supply the necessary fuel. However, this is 3 inefficient, because the payload capacity of the vehicles is only being used for one leg of each journey.

To overcome the above problem, composite trailers have been constructed that provide for the transport of both liquids and solids. Such trailers have previously been known in the transport industry as "camel trailers", and those trailers have typically comprised a load supporting tray, with a liquid storage compartment disposed below the tray. Typically, those trailers are conversions of existing tray-type trailers, in which the area below the tray is enclosed to create a chamber for containing the desired liquid. Such trailers, however, because of their pre-conversion construction, have limited liquid capacity and are not readily able to satisfy regulatory safety requirements.

It is an object of the present invention to provide a trailer that has a dual loading capacity, for the transport of solids and liquids, that overcomes or at least alleviates problems associated with the prior art. It is a further object of the invention to provide a trailer which has a substantially greater liquid carrying capacity than prior art trailers. It is still a further object of the invention to provide a trailer which meets or exceeds known safety standards for the carriage of dangerous liquids, such as fuel.

According to the present invention there is provided a trailer including an elongate liquid storage container having a generally planar roof and a base depending from edge regions of said roof and defining a compartment for liquid storage between the said roof and said base, said trailer further including a load supporting arrangement for supporting a load over said roof, said roof being formed substantially of sheet metal and including a centrally located strengthening channel extending substantially the full elongate length thereof and said roof extending laterally from either side of said channel to said edge regions in a substantially planar manner.

Where the roof is described as being generally planar, that expression allows for deviation from a true planar construction, by way of the channel formed substantially centrally of the roof and also by the manner in which the roof extends on either side of the channel. In this latter respect, the side extensions of the channel preferably each extend laterally thereof to the defined 4 edge regions from which the base depends in a substantially planar manner, but with allowance particularly for angular deviation between adjacent sections of the side extensions. In one embodiment, the side extensions extend substantially horizontally from either side of the channel, but deviate downwardly approximately midway to the side edge regions, at an angle of approximately 50 from horizontal, The point of downward deviation forms a longitudinal strengthening break or rib to additionally strengthen and stiffen the roof against bending or twisting. This embodiment is an example only and the roof could, by way of further example, include further ribs by a plurality of downward deviations spaced laterally across the side extensions. Thus, while the roof is described as being generally planar, that expression as used accommodates deviations from true planar.

A liquid storage container having the above roof construction advantageously allows the roof to be formed in a generally planar manner, as the channel provides a significant strengthening effect longitudinally thereof, so that a platform or other load supporting arrangement may be conveniently supported on the roof. The load supporting arrangement permits support of a load above the liquid storage container, so that the trailer may carry liquid within the container and/or a load above the container. Thus, the trailer can carry two different types of loads simultaneously, or more particularly, can carry separate loads in the container or on the load supporting arrangement. The roof of the container also advantageously minimises the height of the container, say compared with traditional tankers that are circular in cross-section and while this reduces the capacity within the container, the loss in capacity is offset by the gain in the height of goods that can be stored on the load supporting arrangement above the container.

The channel preferably extends laterally across a significant portion of the width between the side edge regions of the roof. In one embodiment, the channel extends for approximately a third of the roof width, although a channel of greater or lesser lateral extent could equally be employed, depending on the type of material from which the roof is formed, and the necessary stiffness and strength of the roof that is required.

The channel preferably has a depth of at least 10% of the width thereof, but the depth, like the width can be varied to suit the material used and the strength and stiffness characteristics required. In one embodiment, the width and depth of the channel is largely determined by the nature of equipment and fittings of the trailer that conveniently can be located within the channel. For example, manway openings leading into the interior of the container can be formed in the channel and closure devices used to close those openings can be accommodated within the channel so as not to project out of the channel when in the closed position. This advantageously allows those fittings to be accommodated within the channel without obstruction to other parts of the trailer, particularly the load supporting arrangement The depth of the channel is an important characteristic of the roof, because the greater the depth, the more the channel intrudes into the interior of the container, and thus the volume of the container is reduced, leading to reduced liquid capacity. On the other hand, it is preferred that the channel depth be sufficient to accommodate many of the various equipment and fittings required by the trailer, without those fittings extending out of the channel.

The channel preferably has planar longitudinal sides that converge toward a planar and generally horizontal base. The sides preferably extend at 450 to horizontal. Such an arrangement particularly resits longitudinal twisting of the roof, and thus the container, in the general plane of the roof.

Alternatively, the channel could be curved, or be a combination of planar and curved sections. The channel may also be ribbed or include breaks as above described. Bracing members may also extend laterally across the channel in spaced-apart relationship longitudinally thereof.

The base that depends from the roof can have any suitable form and typically will include side walls depending from the edge regions of the roof, which extend to a floor. The transition between the side walls and the floor may be a curved section to minimise stress concentration between the side walls and the floor, although it could equally be configured differently.

6 The roof and base are preferably fabricated from the same material, and that material preferably is steel, plate stainless steel, mild steel or aluminium.

Preferably the sheet material is in the range between 4 mm and 6 mm.

Overlying the roof is a support structure for supporting a load supporting arrangement, such as a longitudinal tray or platform. The support structure may include rails, bars, beams etc, formed such as by metallic pressings which may be fixed to the outer surface of the roof for this purpose and a plurality of such pressings may be spaced longitudinally and laterally of the roof.

Alternatively, a plurality of elongate pressings that extend over substantially the full longitudinal extent of the roof may be spaced laterally across the roof. In a preferred embodiment four such elongate pressings are spaced laterally across the roof, with two pressings being provided on each of the side extensions thereof. It is preferred that the channel is not used as a location for the support structure, so that the space within the channel is available for other equipment or fittings.

The support structure may be fixed or attached to the roof by any suitable manner, such as by welding, or nut and bolt fasteners, and the load supporting arrangement may be fixed or attached to the support structure in the same manner.

The container is such that the roof structure contributes significant strength and stiffness thereto and advantageously provides a convenient supporting surface for supporting a load supporting arrangement. The container can also conveniently be arranged to extend the full elongate length of a normal semi-trailer and in this respect, the container may include a forward section that overlies the connection point of the trailer to a prime mover, a middle section, immediately adjacent and rearward of the forward section, and a rear section that overlies the rear axles and wheels of the trailer. For maximum capacity of the trailer, each of these sections has a different crosssectional area. Typically, the front section will have the least cross-sectional area or capacity, followed by the rear section and the middle section has the greatest cross-sectional area and thus the greatest capacity. In this arrangement, the middle section extends between the connecting section of a 7 prime mover provided to tow the trailer, and the rear wheels fitted to the trailer.

In this section, there is no obstruction preventing the container to extend as low as is allowable toward the ground, while in the forward and rear sections, the connection for the prime mover and the wheel arrangement respectively restrict maximum downward extent.

To ensure maximum capacity of the liquid storage container, the invention provides in a further aspect thereof, a transition structure between the forward and middle sections of the container and preferably also the middle and rear sections. The transition structure maximises the gradient of transition between the forward and middle sections, so that the maximum depth of the middle section is achieved relatively close to the connection between the forward and middle sections.

The transition structure supports the container in the region between the forward and middle sections so as to prevent collapse of the container in that region when the container is loaded with liquid. An alternative to the transitional structure of the invention is to arrange the transition region to have a gradual slope between the forward and middle sections, but in that arrangement, the capacity of the container is reduced.

The transition structure according to the invention includes a first member which is attached to the base of the forward section of the container, a second member which is attached to the base of the middle section of the container, and a transition member extending between said first and second members and the structure being arranged to absorb load in the transition region to support the container between the forward and middle sections.

The transition structure preferably includes a pair of planar sheet metal plates located on either side of the base and extending parallel to the longitudinal axis of the container, although a single plate positioned centrally of the base could also be employed. In either arrangement, the transition member is preferably a web that extends between the first and second members and preferably the web is arranged to have an outwardly facing concave edge.

Preferably the transition structure is formed in a T-section having web and flange sections.

8 The sheet metal plates are preferably formed from the stainless steel and are preferably welded to the base of the container. The sheet plate can have any suitable thickness, but one preferred embodiment the sheet has an 8mm thickness.

The attached drawings show an example embodiment of the invention of the foregoing kind. The particularity of those drawings and the associated description does not supersede the generality of the preceding broad description of the invention.

Figure 1 is a side view of a trailer according to the invention.

Figure 2 is a cross sectional view of the trailer through 1I II of Figure 1.

Figure 3 is a cross sectional view of the trailer through III III of Figure 1.

Figure 4 is a cross sectional view of the trailer through IV IV of Figure 1.

Figure 5 is a cross sectional view through V V of Figure 1.

Figure 6 is a side view of a transition structure for use in the trailer of Figure 1.

Figure 7 shows the connection between the base of the trailer of Figure 1 to a prime mover.

Figure 8 is a plan view of the transition structure of Figure 6.

Figure 9 is a further side view of a transition structure for use in the trailer of Figure 1.

Figure 10 is a view of a further transition structure.

Figure 11 shows a further connection between the base of the trailer of Figure 1 to a prime mover.

Figure 12 shows a wheel arch to accommodate the rear wheels of the trailer of Figure 1.

Figure 13 is a cross sectional view through XIII XIII of Figure 1.

Figure 1, is a side view of a trailer 10 connected to a prime mover 11.

The prime mover 11 can be of any known form and includes a trailer connector of known form for connecting it to the trailer 10. The connection, as would be appreciated by a person skilled in the art, is made in the region of the centre- 9 line 12 and includes a suitable coupling that allows relative pivoting movement between the trailer and the prime mover.

The trailer 10 includes a container defined by a forward section 13, a middle section 14 and a rear section 15. As is readily apparent from Figure 1, the forward section 13 is located for its major lengthwise extent, over the rear end 16 of the prime mover 11. The rear section 15 is located for its major lengthwise extent over the rear wheels 17 of the trailer 10. Each of the forward, middle and rear sections of the trailer 10, has a different cross-sectional area.

The forward section 13 has the smallest cross-sectional area, followed by the rear section 15 and the middle section 14. The respective cross-sections of the forward section 13, the middle section 14 and the rear section 15 are shown in Figures 2, 3 and 4 respectively.

It can be seen from each of Figures 2 to 4 that the trailer 10 includes a roof 18 and a base 19. It can also be seen that the configuration of the roof 18 is constant throughout each of the sections 13 to 15, while the configuration of the base 19 is not constant. Referring to the roof 18, the specific shape thereof is shown in Figure The roof 18 includes a central channel 20 that is defined by a pair of inwardly converging walls 21 and a base 22. The base 22 is substantially planar. Side extensions 23 extend from either side of the channel 20 and each such extension comprises a first section 24 that depends from the upper edge of each wall 21, and a second section 26 which is angled downwardly with respect to the first section.

The channel 20 contributes to strengthening and stiffening the roof 18, and facilitates adoption of a generally planar (as hereinbefore described) roof.

The channel 20 extends substantially the full length of the trailer 10 and the roof 18 so constructed provides a convenient support surface for supporting a load supporting arrangement. The rib or break 27 formed between the first and second sections 24, 26 also contributes to the strength and stiffness of the roof 18, but to a lesser extent than the channel At the free edge of the second section 26, a downwardly depending lip 28 extends for connection to the base 19, such as by welding. Referring back to Figures 2 to 4, the base 19 includes side walls 29 and 30 and a floor 31. The transition 32 between the side walls 29, 30 and the floor 31 is curved as shown, while the floor 31 is also slightly curved.

The transition between the forward and middle sections 13 and 14, and between the middle and rear sections 14 and 15 is a unique feature of the present invention. The transition includes a transition structure, a side view of which is shown in Figure 6. The transition structure 32 includes a sheet metal plate configured to have a first member 33 and a second member 34 on either side of a transition member 35. Each of the members 33 to 35 is fixed to the underneath of the floor 31 of the base 22, such as by welding, and the form of attachment is shown in Figure 7, which corresponds to the area circled and marked VII in Figure 2. In this arrangement, the member 33 of the transition structure 32 is welded to a pressed rail 36, which itself is welded to the underneath surface of the floor 31. The member 33 is further welded to a plate 37 that is fixed to each of the rails 36 by welding, so that the transition structure is T-shaped. The plate 37 is shown in plan view in Figure 8 and that view shows a plurality of holes 38 that are provided for fixing the transition structure 32 to a skid plate 39 (see Figure that extends along the base of the rails 36 to protect the floor 31 from damage. A side view of the transition structure 32 is shown in Figure 9, in which the plate 37 is also shown.

A recess 40 in the first member 33 is provided to accommodate the bolt heads of bolts that are provided to bolt the plate 37 to the skid plate 39. This arrangement is evident from Figure 9.

The transition structure 32 advantageously supports the trailer 10 in the region of connection between the forward and middle sections 13 and 14, so that a sharp or abrupt increase in the cross-sectional areas from the forward to the middle section can be made without causing rupture of the container when it is filled with liquid, and so that the capacity of the container can be maximised. Without the transition structure, the container is likely fail in that region. Without the transition structure, a far more gentle transition between the respective sections 13 and 14 would be required, with a resulting loss in container capacity.

11 As can be seen from Figure 3, a pair of rails 41 extend along the underneath of the floor 31 of the middle section 14. A skid plate will extend between the rails 41 and be connected thereto, like the arrangement of the skid plate 37 and the rails 36 shown in Figure 2. Likewise in Figure 4, rails 42 are provided.

The transition region between the forward and middle sections 13 and 14 includes a throat 43, which is shown in Figure 1. The throat 43 is a fabricated part of the trailer 10 that extends between and connects the forward and middle sections 13 and 14. The throat 43 is arranged to extend between the side and base walls 29, 30 and 31 of the respective forward and middle sections 13 and 14 and is shaped to maximise the transition gradient between the forward and middle sections.

A transition arrangement similar to that described between the forward and middle sections 13 and 14 is also provided between the middle and rear sections 14 and 15, even though the transition between those sections is less abrupt than between the forward and middle sections. Figures 10 and 11 show a side and end view of the transition structure provided between the middle and rear sections. Because the arrangement is generally the same as that shown in Figures 6 and 9, like components are referenced with the same numerals, plus 100.

The trailer 10 includes a plurality of support rails 44 to 47 located on the upper surface of the roof 18 for supporting a load bearing structure and in Figures 1, 2 and 4, a load supporting tray 44 is shown. The tray 48 is fixed to the rails 44-47 by welding, or other suitable attachment and the tray can be used to support any suitable load, such as a palletised load. The tray 48 could be equipped with a housing such as a retractable curtain shelter, or other such arrangements that are well known in the art.

As is apparent from Figures 2 to 4, the tray 48 can be arranged to fit over equipment or fittings located within the channel 20. This advantageously positions such fittings in a relatively protected environment, but which are easily accessible through appropriately located openings in the tray. Additionally, the 12 depth of the channel can be such as to ensure the fittings do not extend above the tray surface.

To further strengthen and stiffen the container, and limit the movement of liquid therewithin, baffles may be incorporated within one or more of the sections 13, 14 or 15 and such baffles preferably are made of metal sheet and extend transversely across the interior of one or more of the respective sections and include openings through central sections thereof and at their lowest point along the floor 31 of the base 19. These latter openings allow complete drainage of liquid from within the container. Posts 49 (see Figures 2 and 4) can also be employed to strengthen and stiffen the interior of the container.

The rear section 15 of the trailer 10 includes a wheel arch to accommodate the wheels which are fixed thereunder. In Figures 12 and 13, the wheel arch comprises a recess 50 provided on either side of the base 19 thereof.

In a trailer according to the invention, the liquid container can have a strength and stiffness vastly superior to trailers constructed for the same purpose previously. The channel section provided in the roof contributes significantly to the strength and stiffness characteristics obtained while the additional use of the transition structure facilitates maximum liquid capacity without disturbing the integrity of the trailer at the critical transition region.

The invention described herein is susceptible to variations, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the above description.

Claims (3)

1. A trailer including an elongate liquid storage container having a generally planar roof and a base depending from edge regions of said roof and defining a compartment for liquid storage between the said roof and said base, said trailer further including a load supporting arrangement for supporting a load over said roof, said roof being formed substantially of sheet metal and including a centrally located strengthening channel extending substantially the full elongate length thereof and said roof extending laterally from either side of said channel to said edge regions in a substantially planar manner.

2. A trailer according to claim 1, said channel having a width in the region of one third the total width between said edge regions of said roof and having a depth in the region of 10% of said total width.

3. A trailer according to claim 1 or 2, and having a first section which, in use, overlies the connection point of the trailer to a prime mover and a second section depending rearwardly of said first section, each of said first and second sections defining a portion of said compartment, with the downward extent of said first section and thus the capacity of the compartment portion of said first section being substantially less than that of said second section, a transition structure extending between said first and second sections, said transition structure including a first member which is attached to the base of said first section and a second member which is attached to the base of said second section and a transition member extending between said first and second members, said transition structure being arranged to absorb load to support said container between said first and second sections. DATED: 10 JUNE 1999 PHILLIPS ORMONDE FITZPATRICK Attorneys for: TIEMAN INDUSTRIES PTY LTD C:\WIMNORD\SHAROMANOREW\PROVS\PCT57820.D