AN IMPROVED TRUCK BODY Field of the Invention.

The present invention relates to mining vehicles and particularly to mining trucks and truck bodies. Background Art.

There are a number of alternate designs for a truck body used to haul overburden in a mining situation. Three such examples include the dual-slope body, the flat floor body and the Mine Specific Design (MSD) body designs.

The dual-slope body design illustrated in Figure 1, includes a V-shaped floor which increases load retention, maintains a low centre of gravity, reduces shock loading, and maintains optimum load distribution on steep inclines and in challenging road or conditions. This design typically includes a reinforced, rolled steel top rail which increases body strength and protects the body from damage caused by the loading tool or by falling material. The floor normally includes a pair floor portions which slope downwardly at an angle of approximately 8° forming the V-shaped floor.

The angled floor portions are directed towards reducing shock loading and centralisation of the load. The dual-slope body design also includes a "ducktail" sloped floor portion at the rear to persist with the retention of loads on steep grades.

The dual slope body also typically includes an approximately 7.5° forward body slope. The flat floor body design illustrated in Figure 2 includes a substantially plain floor although wine with a slight incline to deliver high payload capacity, high dump clearances and smooth, controlled dumping. The flat floor designed provides a consistent wear characteristic on the tail of the body rather than the increased wear characteristic caused by the ducktail slope of the dual-slope design. The flat floor body designed includes an approximately 12° forward body slope to improve load retention on better maintained haul roads.

The Mine Specific Design (MSD) body illustrated in Figure 3 is based on the flat floor body designed and is customised to maximise payload potential and minimise costs-per-tonne. Each MSD body design is typically created according to the mine site profile to develop body suitable for a mine's individual needs.

A variety of body liners are available to save weight and help extend the body system's life. Wear surfaces and liners are equipped to handle tough impact loads whilst resisting abrasion. Wear plates deliver long life in high wear areas.

As can be seen from Figures 1-3, all of the conventional truck body designs of the square variety with angled sidewalls. This forces an operator to lift the loading tool over the side wall in order to fill the body. If the operator does not raise the loading tool sufficiently, the loading tool is prone to contacting the sidewalls which typically damages the side wall.

Conventional truck bodies particularly those for overburden trucks are extremely heavy with some truck bodies weighing up to 63 tonnes. Therefore, any reduction in weight of the truck body would allow more payload to be earned, thereby increasing the cost per tonne of payload which the mine can make. It is however important that any reduction in weight does not sacrifice the operability and function of the body.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country. Summary of the Invention.

The present invention is directed to an improved truck body, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

With the foregoing in view, the present invention in one form, resides broadly in an improved truck body including a bottom floor, a headboard and two side walls together defining a volume for carrying a load with an opening opposite the headboard for emptying the load, the bottom floor having a rear section adjacent the opening, the rear section including an arcuate floor portion that is arcuate around an axis that is substantially laterally to the truck body adapted to eject the load from the truck body when the truck body is raised.

In a second form, the present invention resides in an improved truck body including a bottom floor, a headboard and two. side walls together defining a volume for carrying a load with an opening opposite the headboard for emptying the load, the bottom floor and the headboard having an arcuate transition zone therebetween.

The truck body of the present invention is normally pivotably mounted on a frame of a truck for movement between lowered and raised positions. The

volume of the truck body is formed by the floor, headboard and opposed sidewalls is normally a material holding cavity.

The truck body of the present invention has numerous attributes and achieves a number of selected milestone criteria. For example, the truck body should be lightweight, strong, durable, practical, but also address the issues that face the mining sector such as wear properties, costs, environment and have safety benefits for personnel in the operating arena and for personnel who encounter the body in maintenance activities.

The body design of the present invention is typically in the order of 25% lighter than a standard original equipment manufacturer (OEM) body with a potential equivalent increase in pay load (material density and wear package dependant).

The truck body of the present invention has been designed to eject the material being out of the body by providing a rear section of the body with an elevated radius in the floor. At a given point in the hoisting operation of the body, the material in the truck body has a bulk shearing effect at a given angle and when the material hits the elevated section the bulk material is ejected out and over the prescribed safety berm area at the tip face of the truck body, minimising spillage, carry back and material roll back under the vehicle rear tyres. This ejection action not only decreases the material dumping times but severely reduces the need for extended hours at the tip head with ancillary equipment for clean up, for example fewer bulldozer, loader, and grader hours which obviously has a significant economic cost benefit, as well as being a benefit to the environment.

The provision of an upwardly arcuate rear floor portion also typically prevents the loaded material from falling from the rear of the truck body whilst the truck body is in motion. This is particularly the case when the truck is being driven up by grade. Normally, the ejection action created by the upwardly curved arcuate portion of the floor only arises when the truck body is raised beyond a predetermined angle, which typically will only occur when the truck body emptying process is activated by the driver.

The rear section of the truck body has also been designed with the rear ejection area to be wider than the front of the body which preferably reduces material

friction during ejection, which also contributes to faster dumping and reduces wear on the rear sections of the body.

In engineering terms, any object (in this case the object being made out of steel) that has self supporting curves/radius at joining points has strength benefits without having to have a complex design to give the object strength. The truck body of the present invention includes self supporting curves/radii wherever advantageous.

The rear section of the body has also been designed for faster loading through the gate and over the top of the sidewalls by providing sidewalls with an arcuate profile, preferably downwardly towards the rear of the truck body. The sidewall will preferably curve downwardly from the upper end of the headboard to the rear of the truck body where the sidewall curves downwardly to meet the floor of the body at the rear.

As a result of the redesigned sidewalls, the operator does not have to lift the excavator boom/bucket any higher than necessary to have the bucket pass over the topmost extremity of the rear of the sidewalls and/or through the gate of the body. This can not be achieved as efficiently with the square OEM standard design.

Another advantage of this design is that it lessens the opportunity for the bucket to contact the top of the sidewalls which drastically reduces damage to the top of the sidewalls, in turn reducing the overall cost and downtime of the trucks. Not only has this design achieved this criteria but the extra height of the body off the berm (the pile of material that forms when the truck body is emptied), due mainly to the upwardly curved rear portion of the tray, also minimizes rear under body, structural and chassis damage as well as denying stresses onto the body hydraulic system raising and lowering the tray, as the body does not come into contact with the berm or dumped material.

The front and rear section of the body side walls have also been designed for strength due to the numerous radius sections but also to take advantage of any wasted areas and to have the correct pay load encapsulated in the body by correct amount of steel. The advantages of this are that there are no unnecessary voids in the body which contributes to a lesser body weight due to no additional or unnecessary steel or areas not being used for payload.

In particular, each sidewall is typically substantially planar on an inner surface, namely that defining the interior space of the truck body. As stated above,

each sidewall is tallest at the headboard end of the truck body and diminishes in height towards the rear of the truck body. The upper edge of the sidewall is preferably arcuate.

The present invention may also reside in an improved truck body including a bottom floor, a headboard and two side walls together defining a volume for carrying a load with an opening opposite the headboard for emptying the load, each of the sidewalls having a plurality of spaced apart strengthening ribs extending continuously from a first sidewall across the underside of the floor of the truck body and partially up the second sidewall. Each sidewall of the truck body of the present invention is preferably provided with a number of strengthening ribs located on the exterior surface of the sidewall. The strengthening ribs will preferably extend continuously from an upper edge of a first sidewall, down the sidewall, across the underside of the floor of the truck body and to the upper edge of the second sidewall. The strengthening ribs are normally spaced apart longitudinally along the length of the sidewall.

The provision of the strengthening ribs means that less material can be used in the construction of the truck body without sacrificing structural integrity or truck body strength.

There may typically be more than one type of strengthening rib provided. For example, a first type of strengthening rib may be provided as described above extending continuously from an upper edge of a first sidewall to the upper edge of the second sidewall.

A second type of strengthening rib may be provided alternately with the first type, namely as the sidewall extends from the headboard to the rear of the truck body, the strengthening ribs may be a first type, a second type, a first type, a second type and so on. Preferably, the second type of strengthening rib is substantially similar in all respects to the first type except that the second type of strengthening rib does not extend all the way to the upper edge of each sidewall. Preferably, the second type of strengthening rib still extends continuously from one sidewall across the underside of the floor of the truck body and partially up the other sidewall. This pattern of strengthening ribs is typically designated as a "whalebone design" by the inventor.

It is also preferred that the sidewalls have a modular design. For example, the sidewalls will typically be manufactured from number of component parts attached to each other to form the sidewall. Portions of the modular sidewall may therefore be replaced more easily. The truck body itself may have a modular design with the floor, sidewalls, and headboard portion manufactured separately and attached to one another to form the truck body. The floor, sidewalls and headboard will typically be attached relative to one another and the attachment may include an arcuate corner section. The arcuate corner sections will typically each be a self supporting corner section and will normally be concave with respect to the volume for carrying the load. For example, the floor and forward wall will typically have a concave arcuate corner portion linking the surfaces of each of these as will each of the sidewalls and the floor.

In addition to the forward wall having a preferably curved or arcuate profile, the sidewalls may also have such a profile. The inventor has found in that providing walls of an arcuate profile or more particularly, with an arcuate transition zone between the sidewalls and the bottom floor, decreases the amount of material which is retained in many truck body after a truck body has been emptied.

With regard to the sidewalls of the truck body, the sidewalls will preferably have a convex arcuate profile with respect to the volume for carrying a load. This arcuate profile of the sidewalls in combination with the preferred rear portion of the truck body being of greater width than the forward portion of the truck body maximizes the amount of material which is ejected from the truck body during the emptying stage and minimises the amount of material which is retained in the truck body. The whalebone design for the sidewalls allows for modular change out of the sidewalls when either worn out or due to operational damage. These modular sections can be replaced with limited downtime of the truck as these are prefabricated and will typically be made available for immediate delivery.

The present invention may also reside in an improved truck body including a bottom floor, a forward wall, and two side walls together defining a volume for carrying a load with an opening opposite the forward wall for emptying the load, the forward wall having an arcuate, self supporting curved configuration which is concave relative to the volume of the truck body.

The headboard of the truck body of the present invention typically includes the forward wall of the truck body and a forwardly extending cabin cover portion.

The forward wall of the truck body is preferably built in a curved/radius for it to be lightweight, strong, but also self supporting. Normally, when viewed from the rear of the truck body, the forward wall has a concave formation.

The curve of the forward wall therefore preferably forms a forwardly extending bulge in the material holding cavity of the truck body.

The main objective of this design is to prevent loaded material to be pushed over the front of the truck which not only has pit floor and tyre cost implications, but an important safety benefit to the operator and any personnel being in this area while the truck is being loaded.

The headboard also typically has a forward extending cabin cover portion. The cabin cover portion preferably has a steeper degree at the front and also slopes downwardly away to the sides of the truck body in order to disperse any material away from the truck cabin and truck tyres if head board loading was to take place.

The headboard may be manufactured in one or more parts for example, the cabin cover portion may be manufactured separately to the forward wall. Each of these components preferably has a bare wall on a first side, normally the side exposed to the load material, and reinforcing ribs on the opposite side in order to improve strength.

The truck body of the present invention is designed with the highest regard to safety and to allow any persons, but in particular maintenance personnel, safe access to the inner chassis components between the truck chassis rails and the floor of the lowered body for maintenance without having to hydraulically lift and positively lock the body in the fully raised position which had its own safety issues. This not only has safety advantages but has time saving advantages both in dollars and labour terms. This practice is not possible to achieve with a standard OEM type body. The truck body of the present invention is therefore provided with truck body chassis rails which extend longitudinally under the floor, and preferably under the strengthening ribs, the truck body. The truck body chassis rails will typically overlie the truck chassis rails when the truck body is attached to the truck.

This design also gives a better centre of gravity than that of a standard OEM body but with the advantage of a larger pay load but still maintaining the correct front and rear axel split ratios specified by the OEM, the benefits of which are a more stable truck, more payload, extended major component life and tyre preservation. Material selection may also play an important part of the design criteria as the body material preferably has the ability to be cold pressed and welded in the field without having to be preheated or post heated. The preferred material of course is also required to be hardwearing, not only in abrasive terms, but also possess the durability to absorb impact in certain zones. The body is also preferably wider than a standard OEM truck body allowing for a larger target area for any type of loading tool. This has huge benefits not only for the operator being able to place the load effectively but minimising the need for rear wheel tyre protectors as the body covers the rear wheels and tyres. In the main, the provision of the wider truck body without a loss of structural integrity is a result of the whalebone design.

The benefits of the load being placed in the body with correct payload has the potential to prevent the body from being overloaded and most importantly preventing material spilling off the body onto the pit floor which has the potential of damage to the tyres and additional cost of ancillary equipment as previously stated for clean up.

The design of the lighter weight body also has distinct advantages in relation to the environment, for example less weight for truck to carry on an empty return trip to the loading face which equates to less fuel burn and tyre wear.

The decrease in ancillary equipment hours due to be more efficient design of the truck body also equates to less fuel burn, all of which lessens CO ₂ emissions into the atmosphere.

In relation to tyres, the more hours achieved out of the equipment tyres due to fewer worked hours of ancillary equipment and fewer tyre damage events combined with lower body weight and more controlled loading and dumping, lowers the number of scrap tyres put into land fills.

Brief Description of the Drawings.

Various embodiments of the invention will be described with reference to the following drawings, in which:

Figure 1 is a perspective view of a prior art truck body known as a dual-slope body.

Figure 2 is a perspective view of a prior art truck body known as a flat floor body. Figure 3 is a perspective view of a prior art truck body known as a

Mine Specific Design (MSD) body.

Figure 4 is a view from the front of a truck body according to a preferred embodiment of the present invention.

Figure 5 is a view from the side of a truck body according to a preferred embodiment of the present invention.

Figure 6 is an isometric view from the rear of a truck body according to a preferred embodiment of the present invention.

Figure 7 is a view from the side of a truck body according to a preferred embodiment of the present invention. Figure 8 is a perspective view from the rear of a truck body according to a preferred embodiment.

Figure 9 is a sectional view along line A-A of Figure 10 of the truck body illustrated in Figure 8.

Figure 10 is a view from the front of the truck body illustrated in Figure 8.

Figure 11 is a perspective view from the underside of the truck body illustrated in Figure 8.

Figure 12 is a view from the front of the truck body illustrated in Figure 8. Figure 13 is a view from the side of the truck body illustrated in Figure

8.

Figure 14 is a detailed 1 :25 scale view of the portion circled in Figure 15.

Figure 15 is a sectional side view along line A-A of the truck body illustrated in Figures 8 to 13, with the sidewall removed.

Figure 16 is a finite element mesh view of the truck body illutsrated in Figure 8 showing the support structure and contoured thickness.

Figure 17 is a topographical finite element mesh view of the truck body

illutsrated in Figure 8 showing the effective stress at locations in the truck body. Detailed Description of the Preferred Embodiment.

According to a particularly preferred embodiment of the present invention, an improved truck body 10 is provided. The improved truck body 10, a particularly preferred embodiment of which is illustrated in the Figures includes a bottom floor 11, a forward wall 12 and two side walls 13 together defining a volume for carrying a load with an opening opposite the headboard 12 for emptying the load, the bottom floor 11 having a rear section adjacent the opening, the rear section including an arcuate floor portion 14 adapted to eject the load laterally from the truck body 10 when the truck body 10 is raised.

The truck body of the present invention is normally pivotably mounted on a frame of a truck for movement between lowered and raised positions, but for simplicity is illustrated separately from the truck chassis. The volume of the truck body is formed by the floor, headboard and opposed sidewalls is normally a material holding cavity, which in the Figure s is empty.

The truck body illustrated ejects the material out of the body 10 by providing a rear section 14 of the body with an elevated radius in the floor 11. At a given point in the hoisting operation of the body, the material in the truck body 10 has a bulk shearing effect at the given angle and when the material hits the elevated section 14, the bulk material is ejected out and over the prescribed safety berm area at the tip face of the truck body, minimising spillage, carry back and material roll back under the vehicle rear tyres.

This ejection action not only decreases the material dumping times but severely reduces the need for extended hours at the tip head with ancillary equipment for clean up, for example fewer bulldozer, loader, and grader hours which obviously has a significant economic cost benefit, as well as being a benefit to the environment.

The ejection action is created by the upwardly curved arcuate portion 14 of the floor only arises when the truck body 10 is raised beyond a predetermined angle, which only occurs when the truck body emptying process is activated by the driver.

The real" section of the truck body 10 has also been designed with the rear ejection area to be wider than the front of the body 10 which reduces material

friction during ejection, which also contributes to faster dumping and reduces wear on the rear sections of the body. This feature is best illustrated in Figure 6.

The rear section of the body has also been designed for faster loading through the gate (the rear opening) and over the top of the sidewalls 13 by providing sidewalls 13 with an arcuate profile, curving downwardly towards the rear of the truck body 10 as illustrated in Figures 5 and 7. The sidewalls 13 curve downwardly from the upper end of the forward wall 12 to the rear of the truck body 10 where the sidewalls 13 curve downwardly to meet the floor 11 of the body 10 at the rear.

As a result of the redesigned sidewalls, the operator does not have to lift the excavator boom/bucket any higher than necessary to have the bucket pass over the topmost extremity of the rear of the sidewalls 13 and/or through the gate of the body.

As illustrated in Figure 6 in particular, each sidewall 13 is substantially planar on an inner surface, namely that defining the interior space of the truck body and an arcuate corner section 15 is provided between the sidewall 13 and the floor 11. As stated above, each sidewall is tallest at the forward end of the truck body and diminishes in height towards the rear of the truck body.

Each sidewall 13 of the truck body 10 of the illustrated embodiment is also provided with a number of strengthening ribs located on the exterior surface of the sidewall and spaced apart longitudinally along the length of the sidewall. A first configuration of strengthening ribs 16 extends continuously from an upper edge of a first sidewall 13, across the underside of the floor 11 of the truck body and to the upper edge of the second sidewall 13.

According to the illustrated embodiment, a second type of strengthening rib 17 is provided alternately with the first type 16. The second type of strengthening rib 17 is substantially similar in all respects to the first type 16 except that the second type of strengthening rib 17 does not extend all the way to the upper edge of each sidewall 13. This pattern of strengthening ribs is designated as a "whalebone design" by the inventor. The whalebone design for the sidewalls 13 allows for modular change out of the sidewalls 3 when either worn out or due to operational damage. These modular sections can be replaced with limited downtime of the truck as these are prefabricated and will typically be made available for immediate delivery.

The forward wall 12 of the truck body is self supporting and when viewed from the rear of the truck body 10, the forward wall 12 has a concave formation. The curve of the forward wall 12 forms a forward the extending bulge in the material holding cavity of the truck body. A forward extending cabin cover portion 18 is provided and has a steeper degree at the front and also slopes downwardly away to the sides of the truck body in order to disperse any material away from the truck cabin and truck tyres if head board loading was to take place.

The truck body of the present invention is designed to allow any persons, but in particular maintenance personnel, safe access to the inner chassis components between the truck chassis rails and the floor 11 of the lowered body for maintenance without having to hydraulically lift and positively lock the body in the fully raised position.

The truck body has truck body rails 19 which extend longitudinally under the floor 11, and under the strengthening ribs, of the truck body. The truck body rails 19 will normally overlie the truck chassis rails when the truck body is attached to the truck.

The body 10 of the illustrated embodiment is wider than a standard

OEM truck body allowing for a larger target area for any type of loading tool. The truck bodu illustrated in Figures 8 to 17 is a truck body having arcuate transition zones located between the bottom wall or floor of the truck body and the front wall and sidewalls respectively. It can be seen from Figure 17 in particular that the advantage of these arcuate transition zones is a drastic reduction in the effective stresses at what would otherwise be the corner portions of the truck body. In fact the peak effectve stress of any area of the truck body of this aspect of the present invention is 50Mpa whereas a conventional truck body wuld have a peak effective stress located in the corners of the truck body of at least 90 Mpa.

Provision of the particular shape of the floor of the truck body of this aspect of the present invention and as illustrated in Figures 14 and 15 in particular creates the advantages. Figure 14 illustrates the arcuate transition zone between the floor and the front wall of the truck body. The front wall of the truck body is also concave relative to the volume to hold the material as illustrated in Figure 15.

In the present specification and claims (if any), the word "comprising"

and its derivatives including "comprises" and "comprise" include each of the stated integers but does not exclude the inclusion of one or more further integers.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.