AU2007346593A1

AU2007346593A1 - A grading apparatus for grading a surface

Info

Publication number: AU2007346593A1
Application number: AU2007346593A
Authority: AU
Inventors: David William Challen; Wallace David Challen
Original assignee: Challen David; CHALLEN WALLACE D
Current assignee: Challen David; CHALLEN WALLACE D
Priority date: 2007-02-06
Filing date: 2007-12-03
Publication date: 2008-08-14
Also published as: CA2677332A1; GB0915285D0; WO2008095223A1; US20100044062A1; GB2459610A

Description

WO 2008/095223 PCT/AU2007/001868 A GRADING APPARATUS FOR GRADING A SURFACE Field of the invention The present invention relates to a grading apparatus 5 for grading a surface. Background Providing adequate roadside drainage is important for 10 maintaining the integrity of road surfaces and also maintaining the health of roadside verges. On many regional roads and highways it is not feasible to provide a gutter and water drainage system. On these roads, the drain consists of a graded channel, or similar culvert 15 formed in the earth at the roadside. Over time, the drains become filled with debris from vegetation, and water running through the drains causes erosion. In some cases, the drain is formed by grading into 20 the earth to form an earth wall (which is also known as a roadside batter) and a table drain. The roadside batter has a steep pitch and the table drain has a low pitch. Formation and restoration of drains, such as table 25 drains, can be difficult, particularly where access to the drain is inhibited. In addition, roadside markers and signs that are located between the road surface and the drain can further inhibit access to the drain. 30 Summary of the invention The present invention provides grading apparatus comprising: WO 2008/095223 PCT/AU2007/001868 -2 an elongate support arm assembly having a mount at one end for attachment to a vehicle, and a grading blade attached to the opposing end of the support arm assembly, 5 wherein the grading blade can be positioned outwardly of the vehicle to grade a surface beside the vehicle as the vehicle moves forward. Preferably, the support arm assembly can be 10 positioned such that the grading blade is disposed outside the track of the vehicle. Preferably, the support arm assembly can be rotated about a first axis with respect to the mount. 15 Preferably, the grading blade can be moved between a lowered position and an elevated position. Preferably, the mount comprises an attachment 20 assembly that includes a shaft that defines the first axis, the support arm assembly being rotatable about the shaft. Preferably, the grading apparatus further comprises a 25 first actuator to control the rotational position of the support arm assembly about the first axis. Preferably, the first actuator is a linear actuator that extends between a mounting bracket and a bracket 30 provided on the support arm assembly.

WO 2008/095223 PCT/AU2007/001868 -3 Preferably, support arm assembly further comprises a telescoping section such that the length of the support arm assembly can be adjusted. 5 Preferably, the grading apparatus further comprises a second actuator within the support arm assembly to facilitate movement of the telescoping section. Preferably, the support arm assembly can also be 10 rotated about a second axis with respect to the mount. Preferably, the second axis is substantially orthogonal to the first axis. 15 Preferably, the support arm assembly can be rotated by at least 150 about the second axis. More preferably, the support arm assembly can be rotated by at least 20* about the second axis. 20 Preferably, the mount comprises an attachment assembly that includes a pivot pin that defines the second axis, the support arm assembly being rotatable about the pivot pin. 25 Preferably, the grading apparatus further comprises a third actuator to control the rotational position of the support arm assembly about the second axis. Preferably, the third actuator is a linear actuator 30 that is arranged to rotate the support arm assembly with respect to the attachment assembly.

WO 2008/095223 PCT/AU2007/001868 -4 Preferably, the grading blade is of quadrilateral shape. Preferably, the grading blade further comprises a 5 replaceable cutting edge. Preferably, the width of the face of the grading blade increases towards the outer end. 10 Preferably, the support arm assembly is connected to the grading blade close to the lower edge of the grading blade. Preferably, the support arm assembly further 15 comprises an elongate arm that extends between the mount of the support arm assembly and a stabilizing arm that intersects the elongate arm to provide lateral support to the elongate arm. 20 The present invention also provides a vehicle comprising the grading apparatus described above. Preferably, the vehicle further comprises a front mounted bucket, and the grading apparatus is mounted to a 25 rear surface of the bucket. Brief description of the drawings In order that the invention may be more easily 30 understood, embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which: WO 2008/095223 PCT/AU2007/001868 -5 Figure 1: is a front schematic view of a grading apparatus according to a first embodiment of the invention, which is attached to a vehicle; 5 Figure 2: is a front schematic view of the grading blade and support arm assembly of the grading apparatus of figure 1; Figure 3: is a front view of the grading blade of the grading apparatus of figure 1 in a 10 lowered position; Figure 4: is a front view of the grading blade of the grading apparatus of figure 1 in a partially elevated position; Figure 5: is a front view of the support arm 15 assembly of the grading apparatus of figure 1; Figure 6: is a top view of the support arm assembly of the grading apparatus of figure 1; 20 Figure 7: is a perspective view of a vehicle to which the grading apparatus of figure 1 has been mounted; Figure 8: is a side elevation of the vehicle of figure 7; 25 Figure 9: is a rear elevation of the vehicle of figure 1; Figure 10: is a rear schematic view of a grading apparatus according to a second embodiment of the present invention; 30 Figure 11: is a plan view of the grading apparatus of figure 10; Figure 12a: is a rear view of a grading blade of a grading apparatus in accordance with an WO 2008/095223 PCT/AU2007/001868 -6 embodiment of the present invention, shown in a first position; Figure 12b: is a plan view of the grading blade of figure 12a; 5 Figure 12c: is a rear view of the grading blade figure 12a in a second position; and Figure 12d: is a plan view of the grading blade of figure 12c. 10 Detailed description Figure 1 shows a grading apparatus 10 according to an embodiment of the present invention. The grading apparatus 10 is attached to a vehicle 100, which may be, 15 for example, a tractor or a wheeled loader as shown in figure 7. In figure 1, the vehicle 100 is shown in a front view. As shown in figure 1, the grading apparatus 10 can be 20 used to grade a surface beside the vehicle 100. That is, the surface to be graded can be located outside the wheel tracks of the vehicle 100. The grading apparatus 10 has an elongate support arm 25 assembly 12, which is attached to mounting points provided on the vehicle 100. A grading blade 14 is provided on the outer end of the support arm assembly 12. Figure 1 shows the grading apparatus 10 in a grading 30 position. The vehicle 100 is positioned on, or beside, the road surface 50 and beside a drain 52. In this grading position the grading blade 14 is positioned beside WO 2008/095223 PCT/AU2007/001868 -7 the vehicle 100. As the vehicle moves, the grading apparatus 10 grades and/or clears the drain 52. The drain 52 shown in figure 1 is in the form of a 5 table drain, which extends downwardly and outwardly with respect to the road surface 50. The lowest point of the drain 52 intersects with the lower end of a roadside batter 54, which extends downwardly and inwardly with respect to the road surface 50. 10 Figures 2 to 6 illustrate the grading apparatus 10 of figure 1. The inner end of the support arm assembly 12 is provided with a mount for mounting the grading apparatus 10 to a vehicle 100. In this embodiment, the mount is in 15 the form of an attachment assembly 16. The attachment assembly 16 can be, for example, welded to the vehicle 100. The attachment assembly 16 is shown schematically in the figures. 20 The support arm assembly 12 includes an elongate arm 18 and a stabilizing arm 20. The grading blade 14 is connected to the outer end of the elongate arm 18. The stabilizing arm 20 intersects the elongate arm 18 adjacent the inner end of the elongate arm 18, and provides lateral 25 support to the elongate arm 18 during operation of the grading assembly 10. The attachment assembly 16 includes a shaft 22 on which the support arm assembly 12 is mounted. The shaft 30 22 extends in a direction that is generally perpendicular to the face 15 of the grading blade 14. The shaft 22 defines an axis about which the support arm assembly 12 can rotate. In this embodiment, the grading apparatus 10 WO 2008/095223 PCT/AU2007/001868 -8 has a mount, which is in the form of holes 24, 26 provided at the inner end of the elongate arm 18 and the stabilizing arm 20. As shown in figure 6, the shaft 22 extends through both holes 24, 26. The support arm 5 assembly 12 can rotate on the shaft 22. Thus, the grading apparatus 10 can be rotated about the shaft 22. To control and adjust the rotational position of the support arm assembly 12 about the shaft 22, the grading 10 apparatus 10 is provided with a first actuator 28. One end of the first actuator 28 is connected to a bracket 30 on the stabilizing arm 20. The opposing end of the first actuator 28 is connected to a mounting bracket (not shown) on the vehicle 100. 15 Movement of the first actuator 28 causes the support arm assembly 12 to rotate about the shaft 22, as indicated by the double-headed arrow A in figure 2. Thus, the grading blade 14 can be raised and lowered as desired. 20 Figure 2 shows the support arm assembly 12 and grading blade 14 in a lowered position, which is generally indicated by arrow L. In this position, the grading blade can positioned outwardly of the vehicle 100, such that a surface beside the vehicle 100 can be graded as the 25 vehicle moves either forward or backward. Figure 2 also shows (in broken lines) the support arm assembly 12 and grading blade 14 in an elevated position, which is generally indicated by arrow E. In this position, the grading blade 14 is within the tracks of the vehicle 100, 30 which is convenient for transport. The elongate arm 18 has a telescoping section such that the length of the elongate arm 18 can be adjusted, WO 2008/095223 PCT/AU2007/001868 -9 such that the grading blade 14 can be moved inwardly or outwardly of the vehicle 100. Thus, the grading blade 14 can be extended or retracted in a direction that is co axial with the elongate arm 18. To facilitate this 5 movement, a second actuator 32 is provided within the elongate arm 18 to control and adjust the length of the elongate arm 18, as indicated by the double-headed arrow B in figure 2. 10 It will be appreciated that the grading apparatus 10 of the first embodiment has two degrees of freedom, as follows: 1. rotation of the support arm assembly 12 about the shaft 22 (as indicated by arrow A), and 15 2. extension/retraction parallel to the elongate arm 18 (as indicated by arrow B) The elongate arm 18 is connected to the grading blade 14 such that the elongate arm 18 is close to the lower 20 edge of the grading blade 14. Accordingly, in use of the grading apparatus 10, the forces applied to the face 15 of the grading blade 14 are generally close to the elongate arm 18. It will be appreciated that this arrangement minimizes the torque applied to the elongate arm 18. 25 In this embodiment, the grading blade 14 is of quadrilateral shape, which broadens towards the outer end. The face 15 of the grading blade 14 can be either flat or curved. In addition, embodiments may be provided in which 30 the grading blade 14 has two opposing faces such that the grading apparatus can be operated in either a forward or backward direction by a corresponding forward or backward movement of the vehicle.

WO 2008/095223 PCT/AU2007/001868 - 10 The grading apparatus 10 can be conveniently attached to a vehicle such as the bucket 110 of a wheeled loading shovel 100, as shown in figures 7 to 9. The bucket is 5 mounted on two arms 112, which can be raised and lowered to change the elevation of the bucket 110. The shaft 22 extends generally rearwardly of the bucket 110. When the mouth of the bucket 110 is facing 10 forward (as shown in figure 7), the shaft 22 is approximately horizontal. However, as the bucket 110 can be pivoted (in other words rolled or tipped), the inclination of the shaft 22 can be varied. 15 Mounting the grading apparatus 10 to the back of the bucket 110 can provide additional adjustability of the position of the grading blade 14. In addition to the two degrees of freedom of the grading blade 14 described previously, the inclination of the face of the grading 20 blade 14 can be adjusted by pivoting (that is, rolling) the bucket 110 on the arms 112. Furthermore, the vertical height of the attachment assembly 16 can be adjusted by raising or lowering the bucket 110. 25 It will be appreciated that mounting the grading apparatus 10 to the front of the vehicle 100 has the additional benefit of the grading blade 14 being positioned generally in front of the vehicle operator. The operator has the grading apparatus 10, the path in 30 front of the vehicle 100 and the path in front of the path in front of the grading apparatus 10 within their field of view.

WO 2008/095223 PCT/AU2007/001868 - 11 When using the grading apparatus 10 of the present invention, an operator positions the grading blade 14 in the desired location relative to the drain. The grading blade 14 can be positioned to scrape a top layer of earth 5 and/or collect debris in the drain. The vehicle 100 is moved forward such that unwanted material/debris, such dirt, rubbish, leaves, etc., to be removed from the drain is pushed in front of the grading blade 14. Once a desired amount of unwanted material has accumulated in 10 front of the grading blade 14, the operator can simply raise the grading blade 14, advance the grading blade 14 in front of the piled unwanted material (by moving the vehicle 100 forward), lower the grading blade 14, and continue grading. The piles of unwanted material can 15 subsequently be removed from the drain. Thus, in use of the grading apparatus 10, the grading blade 14 can be arranged such that unwanted material is not pushed toward the road surface, as can occur with the use of a conventional grader. 20 In use of the grading apparatus 10, the support arm assembly 12 and grading blade 14 can be raised (for example, by operating the first actuator 28) into a generally vertical orientation to pass an object, such as 25 a post or similar object, that inhibits access to the drain. In many cases, the drain can be graded up to point at which the object is perpendicular to the drain. This is because the grading apparatus 10 can be rotated and raised adjacent the object as previously described. The 30 vehicle 100 is then free to advance past the object and continue grading on the other side of the object.

WO 2008/095223 PCT/AU2007/001868 - 12 It will be appreciated that in use of the grading apparatus 10 to grade a table drain, such as that shown in figure 1, more material may be accumulated toward the outer end of the grading blade 14 than at the inner end. 5 Providing a grading blade 14 of the shape shown in figures 1 to 9 assists in reducing the weight of the grading blade 14. One of the advantages of the grading apparatus 10 is 10 that surfaces can be graded without requiring the vehicle 100 to have wheels in the drain or without requiring the vehicle 100 to straddle the drain. Accordingly, steep surfaces can be graded without subjecting the operator or the equipment to unnecessary risk of injury or damage. 15 It will be appreciated that the grading apparatus 10 can be used to grade or clear any surface, and is not limited to use in connection with drains. 20 The first and second actuators 28, 32 can be linear actuators, such as hydraulic cylinders and pistons. It will be appreciated that hydraulic cylinders can easily be incorporated into a vehicle's existing hydraulic circuit. 25 The grading apparatus 10 of the present invention may alternatively be mounted behind a vehicle. In one example, the grading apparatus can be mounted to the backhoe. 30 The grading apparatus may be mounted on a vehicle such that the support arm assembly 12 and grading blade 14, when in a lowered position, extend outwardly and to the left of the vehicle. This arrangement would be well WO 2008/095223 PCT/AU2007/001868 - 13 suited to those countries in which vehicles drive on the left-hand side of the road. Alternatively, the grading apparatus may be mounted on a vehicle such that the support arm assembly 12 and grading blade 14, when in a 5 lowered position, extends outwardly and to the right of the vehicle. This arrangement would be well suited to those countries in which vehicles drive on the right-hand side of the road. 10 Figures 10 and 11 illustrate a grading apparatus 210 according to a second embodiment of the present invention. The grading apparatus 210 has a support arm assembly 212 that is provided with a mount for mounting the grading apparatus 210 to a vehicle. In this embodiment, the mount 15 is in the form of an attachment assembly 216. The support arm assembly 212 includes an elongate arm 218 to which the grading blade 214 is attached, such that the grading blade 214 is provided on the outer end of the 20 support arm assembly 212. The grading apparatus 210 has an attachment assembly 216 for attaching the grading apparatus 210 to a vehicle. In this embodiment, the attachment assembly 216 includes a 25 mounting plate 240 that is provided with four mounting holes 238 for receiving threaded shafts that extend from a portion of the vehicle, such as the bucket of a front loader. 30 In this embodiment, the attachment assembly 216 has mounts 224 that support the support arm assembly 212. Shafts 222 connect mounts 226 on the inner end of the support arm assembly 212 to the mounts 224 of the WO 2008/095223 PCT/AU2007/001868 - 14 attachment assembly 216. The shafts 222 extend in a direction that is generally perpendicular to the face 215 of the grading blade 214. The shafts 22 define a first axis about which the support arm assembly can be rotated. 5 Thus, the support arm assembly 212 can rotate on the shafts 222 to enable the grading blade 214 to be raised and lowered, as indicated by the double-headed arrow A in figure 10. 10 To control and adjust the rotational position of the support arm assembly 212 about the shafts 222, the grading apparatus 210 is provided with a first actuator 228. One end of the first actuator 228 is connected to a mounting bracket 230 that is provided on the attachment assembly 15 216. The opposing end of the first actuator 228 is connected to the elongate arm 218 by a second bracket 231. Movement of the first actuator 228 causes the support arm assembly 212 to rotate about the shafts 222, as 20 indicated by arrow A. Thus, the grading blade 214 can be raised and lowered as desired. For clarity, only the outer portion of the first actuator 228 has been shown in figure 11. 25 The elongate arm 218 has a telescoping section 219 that enables the length of the elongate arm 218 to be adjusted, such that, in use, the grading blade 214 can be moved inwardly or outwardly of the vehicle. Thus, the grading blade 214 can be extended or retracted in a 30 direction that is co-axial with the elongate arm 218. To facilitate this movement, a second actuator 232 is provided within the elongate arm 218 to control and adjust the length of the elongate arm 218, as indicated by the WO 2008/095223 PCT/AU2007/001868 - 15 double-headed arrow B in figure 2. Figure 10 shows the position of grading blade 214 when retracted in solid lines, and also shows the grading blade 214 in an extended position in broken lines. 5 The telescoping section 219 is arranged within an outer portion of the elongate arm 218. To facilitate movement of the telescoping section 219, rollers 233 are provided within the elongate arm 218. The rollers 233 10 enable the telescoping section 219 to move freely within an outer portion of the elongate arm 218. The attachment assembly 216 includes a support plate 242 and a bracing plate 244. Both the support plate 242 15 and the bracing plate 244 project outwardly from the mounting plate 240. The mounts 224 are connected to the support plate 242 by a pivot pin 234. The mounts 224 can be rotated on the pivot pin 234, and thus rotated with respect to the support plate 242. The pivot pin 234 20 defines a second axis about which the support arm assembly can be rotated. As indicated by figures 10 and 11, the first and second axes are substantially orthogonal. The pivot pin 234 lies in a plane that is parallel 25 with the face 215 of the grading blade 214. Accordingly, the support arm assembly 212 can be rotated about the pivot pin 234 with respect to the attachment assembly 216, as indicated by double-headed arrow C in figure 11. 30 To control and adjust the rotational position of the support arm assembly 212 about the pivot pin 234, the grading apparatus 210 is provided with a third actuator 236. One end of the third actuator 236 is connected to WO 2008/095223 PCT/AU2007/001868 - 16 via a bracket to the mounting plate 240. The opposing end of the third actuator 236 is connected to via a bracket to the mounts 224. 5 Movement of the third actuator 236 causes the mounts 224, and thus also the support arm assembly 212, to rotate about the pivot pin 234, as indicated by arrow C. Thus, the fore-and-aft angle of the grading blade 214, with respect to the attachment assembly 216 can be set as 10 desired. In this embodiment, the angle subtended by the grading blade 214 is approximately 250. Furthermore, in this embodiment the grading blade 214 can be angled forward (fore) by approximately 20*. In addition, the grading blade 214 can be angled rearward (aft) by 15 approximately 5'. However, it will be appreciated that the angle subtended by the grading blade 214, and the maximum fore and aft angles, can be selected as desired. The maximum fore and aft angles can be selected as 20 desired. It will be appreciated that these maximum angles may be limited by interference with the vehicle components, such as the bucket and/or tyres. The ability to adjust the fore-and-aft angle of the 25 grading blade 14 provides the operator with the freedom to drag unwanted material out from the drain toward the road surface, or urge unwanted material away from the road surface. 30 It will be appreciated that the grading apparatus 210 of the second embodiment has three degrees of freedom, as follows: WO 2008/095223 PCT/AU2007/001868 - 17 1. rotation of the support arm assembly 212 about the shafts 222 (as indicated by arrow A), 2. extension/retraction parallel to the elongate 5 arm 218 (as indicated by arrow B), and 3. rotation of the support arm assembly 212 about the pivot pin 236 (as indicated by arrow C) 10 The grading apparatus 210 can also be conveniently attached to the bucket 110 of a vehicle, such as a wheeled loading shovel 100. The ability to pivot/roll the bucket 110 provides the grading apparatus with increased degree of freedom. In some situations it may be desirable to 15 adjust the inclination of the face 215 of the grading blade 214 for grading/clearing. Figures 12a to 12d illustrate the grading/clearing of a table drain 52 that has a vertical batter 54. Access to 20 the bottom of the drain 52 can be difficult when the face of grading blade 314 is vertical and perpendicular to the batter 54. Rotating the support arm assembly 312 forward about the second axis (as indicated by arrow X) and simultaneously rolling the bucket forward (as indicated by 25 arrow Y) enables the cutting edges of grading blade 314 to match the pitches of both the batter 54 and the drain 52. Thus, the lower, outermost corner of the grading blade 314 can access the bottom of the drain 52. 30 The grading blade 214 of has a replaceable cutting edge 240 that is attached to the main part of the grading blade 214 by a series of fasteners 242. When wear of the cutting edge 240 becomes excessive, the cutting edge 240 WO 2008/095223 PCT/AU2007/001868 - 18 can be readily replaced. Similarly, if a particular application requires a different shape of cutting edge of the grading blade 214, the cutting edge 240 can be replaced as appropriate. 5 The first, second and third actuators 228, 232, 236 can be linear actuators, such as hydraulic cylinders and pistons. Such hydraulic cylinders can easily be incorporated into a vehicle's existing hydraulic circuit. 10 The shape of the grading blade may be selected to suit the desired application. For example, if a spoon shaped drain is to be graded, a grading blade (or the replaceable cutting edge) having a curved bottom edge may 15 be more appropriate. The grading apparatus of the present invention may be provided with an attachment assembly that can be connected to a vehicle by way of locking pins, such that the grading 20 apparatus can be readily attached to, or removed from, the vehicle when desired. The grading apparatus may be provided with a further actuator to control and adjust the inclination of the 25 grading blade with respect to the mount. This would be suitable in embodiments that were to be mounted to a fixed part of a vehicle, rather than a pivotable bucket. It will be understood to persons skilled in the art 30 of the invention that many modifications may be made without departing from the spirit and scope of the invention.

WO 2008/095223 PCT/AU2007/001868 - 19 In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as 5 "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Claims

1. A grading apparatus comprising: an elongate support arm assembly having a mount 5 at one end for attachment to a vehicle, and a grading blade attached to the opposing end of the support arm assembly, wherein the grading blade can be positioned outwardly of the vehicle to grade a surface beside the 10 vehicle as the vehicle moves forward.

2. A grading apparatus as claimed in claim 1, wherein the support arm assembly can be positioned such that the grading blade is disposed outside the track of 15 the vehicle.

3. A grading apparatus as claimed in either claim 1 or 2, wherein the support arm assembly can be rotated about a first axis with respect to the mount. 20

4. A grading apparatus as claimed in claim 3, wherein the grading blade can be moved between a lowered position and an elevated position. 25

5. A grading apparatus as claimed in either claim 3 or 4, wherein the mount comprises an attachment assembly that includes a shaft that defines the first axis, the support arm assembly being rotatable about the shaft. 30

6. A grading apparatus as claimed in any one of claims 3 to 5, further comprising a first actuator to control the rotational position of the support arm assembly about the first axis. WO 2008/095223 PCT/AU2007/001868 - 21

7. A grading apparatus as claimed in claim 6, wherein the first actuator is a linear actuator that extends between a mounting bracket on the vehicle and a 5 bracket provided on the support arm assembly.

8. A grading apparatus as claimed in any one of claims 1 to 7, wherein support arm assembly further comprises a telescoping section such that the length of 10 the support arm assembly can be adjusted.

9. A grading apparatus as claimed in claim 8, further comprising a second actuator within the support arm assembly to facilitate movement of the telescoping 15 section.

10. A grading apparatus as claimed in claim 3, wherein the support arm assembly can also be rotated about a second axis with respect to the mount. 20

11. A grading apparatus as claimed in claim 10, wherein the second axis is substantially orthogonal to the first axis. 25

12. A grading apparatus as claimed in either claim 10 or 11, wherein the support arm assembly can be rotated by at least 150 about the second axis.

13. A grading apparatus as claimed in claim 12, 30 wherein the support arm assembly can be rotated by at least 200 about the second axis. WO 2008/095223 PCT/AU2007/001868 - 22

14. A grading apparatus as claimed in any one of claims 10 to 13, wherein the mount comprises an attachment assembly that includes a pivot pin that defines the second axis, the support arm assembly being rotatable about the 5 pivot pin.

15. A grading apparatus as claimed in any one of claims 10 to 14, further comprising a third actuator to control the rotational position of the support arm 10 assembly about the second axis.

16. A grading apparatus as claimed in claim 15, wherein the third actuator is a linear actuator. 15

17. A grading apparatus as claimed in any one of claims 1 to 16, wherein the grading blade is of quadrilateral shape.

18. A grading apparatus as claimed in claim 17, 20 wherein the width of the face of the grading blade increases towards the outer end.

19. A grading apparatus as claimed in any one of claims 1 to 18, wherein the grading blade further 25 comprises a replaceable cutting edge.

20. A grading apparatus as claimed in any one of claims 1 to 19, wherein the support arm assembly is connected to the grading blade close to the lower edge of 30 the grading blade.

21. A grading apparatus as claimed in any one of claims 1 to 20, wherein the support arm assembly further WO 2008/095223 PCT/AU2007/001868 - 23 comprises an elongate arm that extends between the mount of the support arm assembly and a stabilizing arm that intersects the elongate arm to provide lateral support to the elongate arm. 5

22. A vehicle comprising the grading apparatus as claimed in any one of claims 1 to 21.

23. A vehicle according to claim 22, further 10 comprising a front mounted bucket, and the grading apparatus is mounted to a rear surface of the bucket.