The apparatus is particularly useful for spreading a material over an existing ground surface, or for levelling, scraping or cutting an uneven surface to achieve a smooth or uniform profile. It should be understood, however, that the invention is not limited to these applications.

BACKGROUND Ground levelling devices such as rakes and spreaders are used to spread sand, gravel or composite material over, for example, a lawn or ground surface.

In many cases, it is desirable that the surface be leveled to a relatively close tolerance, particularly for grassed areas, such as golf courses or bowling greens where the surface profile of the grass is important. The level or surface profile of the grass is often adjusted by spreading material such as sand over the surface of the lawn. To ensure that the overall surface is level or has the required profile, it is necessary to spread the sand around evenly. In the past, this has been accomplished by handheld spreading devices, which are useful for smaller areas, but are not efficient at levelling a large area. Further, with known devices, it is difficult to adjust the level of the material spread on the ground to a sufficient degree of accuracy.

An example of a known spreading device is the hand propelled wheeled leveller/rake, shown in Australian Patent No. 561245. This device has a wheeled frame and a rake pivotally connected to the frame. The rake has a frame with a number of spreading bars, and is adapted to sit flatly on the ground. The connection point allows the rake to pivot with respect to the wheeled frame.

When in use, there is no apparatus to control the angle of the rake to the ground, and the rake is adapted to sit flatly. This limits the ability of the leveller to cut away soil and profile the surface of the ground. Further, there is no means to allow the rake to deflect if the rake encounters excessive pressure.

Another example of a spreading device is shown in Australian Patent No.

559332. This document discloses a garden implement having a frame supported

by wheels, and a rake having a number of tines. When pushed one way the tines contact the ground and the device acts as a rake. When pulled in another direction, the wheels contact the ground, and the tines do not dig into the ground.

This enables the rake to be used to move material over a surface without lifting the rake on the return sweep. However, this device does not allow the user to control the position of the rake or tines. While larger spreading devices are available, these are heavy and not maneuverable in confined spaces. It is also not desirable to drive a heavy machine on lawned surfaces. Large machinery is also substantially more expensive to operate, and may require skilled users.

Another disadvantage is that when levelling a ground surface, the blade could dig into the surface, making it difficult to move the apparatus.

The present invention seeks to overcome at least one of the abovementioned problems by providing a levelling apparatus that is adjustable.

Further, the present invention seeks to provide an apparatus that can level large surfaces more easily without the complexity or weight associated with existing devices.

SUMMARY OF THE INVENTION Accordingly, the present invention provides an apparatus for levelling a surface, the apparatus having support means for supporting a carrier above the surface, and a blade attached to the carrier, wherein the position of the blade is adjustable with respect to the surface.

Preferably, the apparatus includes a main member attached to the carrier for movement and control of the apparatus. The main member may be attached to a handle or vehicle connection point to move the apparatus over the surface.

Preferably, the apparatus includes an adjustment mechanism for adjusting the angle of the blade to a levelling position, said levelling position being determined relative to the main member. This allows the user to determine the angle of the blade to the surface, which effects the force required to move the apparatus over the surface.

Preferably, the apparatus includes a biasing mechanism for biasing the blade to the levelling position, wherein excessive force against the blade causes

the blade to deflect from the levelling position to a biased position. This feature has the advantage of preventing the apparatus getting stuck in a particular spot if an immovable object is encountered, or too much force is being applied to the blade.

In one form, the support means includes wheels. The wheels may be mounted on supports pivotally attached to the carrier.

In another form, the supports may include skids for sliding the apparatus over the ground. Preferably, the skids are rotatably attached to the carrier if the blade.

In an alternate form, the support means may be connected to the main member. The support means may include wheels or skids.

BRIEF DESCRIPTION OF THE DRAWINGS Several preferred embodiments will now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a levelling apparatus in accordance with a first embodiment of the present invention; Figure 2 is a perspective view of an upper section of the levelling apparatus shown in figure 1; Figure 3 is a side view of the upper section of the levelling apparatus shown in figure 1; Figure 4a is a front view of a second embodiment of a carrier of the levelling apparatus; Figure 4b is a side view of the carrier of figure 4a; Figure 5a is a front view of a second embodiment of a blade of the levelling apparatus; Figure 5b is a side view of the carrier of figure 5a; Figure 6a is a front view of the second embodiment of the blade mounted to the second embodiment of the carrier of the levelling apparatus in a first arrangement; Figure 6b is a side view of the apparatus of figure 6a;

Figure 7a is a front view of the second embodiment of the blade mounted to the second embodiment of the carrier of the levelling apparatus in a second arrangement; Figure 7b is a side view of the apparatus of figure 7a.

Figure 8 is a side schematic of a support means and carrier and blade of the apparatus of figure 1; Figure 9 is a side schematic view of a third embodiment of the apparatus of the present invention with the blade in a first position; Figure 10 is a side schematic partial cross section of the apparatus of figure 9; Figure 11 is a side schematic view of the apparatus in figure 10 with the blade in a second position; Figure 12 is a side schematic view of the carrier and support means shown in figure 9 Figure 13a to 13c are various views of a bucket attachment for the apparatus of the present invention; Figure 14a and 14b are various views of a blade attachment for the apparatus of the present invention; Figure 15 is a side view of the apparatus shown in figure 10, including a connection means; Figure 16 is a rear view of the apparatus show in figure 15.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In figure 1, a levelling apparatus 10 is shown. The apparatus 10 includes a carrier 12 pivotally mounted to supports 14 and 16. A blade 20 is attached to the carrier 12. A main member 22 is attached to the carrier 12 to direct the action of the carrier and blade 20. A handle 24 is attached to an upper end of the main member 22.

Also attached to the main member 22 is an adjustment mechanism 25, best seen in figures 2 and 3. The adjustment mechanism 25 includes top support 36. A rod 34 connects the adjustment mechanism 25 to the carrier 12 by carrier arm 37. By moving the position of the top support 36, the rod 34 changes the

angle of the carrier 12 with respect to the main member 22. This change in angle of the carrier 12 also changes the angle of the blade 20 to the main member 22.

For a given angle of the main member 22 to the surface to be leveled, changing the position of the top support 36 changes the angle of the blade 20 the surface. This in turn changes the depth of cut of the blade 20 into the surface.

Thus, the user can change the depth of cut of the blade 20 by changing the position of support 36.

A biasing mechanism 40 is incorporated onto the adjustment mechanism 25 by way of biasing clamp 32 provided on rod 34. Clamp 32 includes a fixing mechanism such as a thumb screw 33 to fix the biasing clamp with respect to rod 34. A biasing member 30, such as a spring shown in figures 1-3, provides a force for keeping the rod 34 positioned relative to the top support 36. Fixing the clamp 32 further along the rod 34 towards the top support 36 increases the compressive force in the spring, thus increasing the biasing force keeping the rod 34 in position relative to the main member 22.

Conversely, fixing the clamp 32 further from the top support 36 reduces the biasing force and therefore reduces the force on the blade 20 required to deflect the blade from its levelling position.

In figure 3, the top support 36 is shown in more detail. A biasing handle 52 is attached to rod head 54. Rod head 54 is adapted so that is will not pass through a holding aperture 58 in top support 36, as shown in figure 3. It is therefore possible to pull the biasing handle 52 towards the handle 24 to move the rod 34 with respect to the support 36. This moves the carrier with respect the main member 22 and therefore adjusts the angle of the blade 20 with respect the main member 22, moving the blade 20 from a levelling position to a biased position 53, as shown in figure 9. Releasing the biasing handle 22 causes the rod 34 to be returned to the position shown in figure 8, wherein the blade 20 is returned to a levelling position from a biased position 53.

It should be noted that the above arrangement allows the angle of the blade 20 with respect the main member 22 to be changed without affecting the biasing force.

In use, a user pulling the apparatus 10 would move the apparatus over a surface to be leveled. The blade 20 would cut into the surface and excess material would build up in front of the blade in its direction of travel. Any pockets or areas below the level of the blade would be filled by excess material in front of the blade 20, and in this way, the surface would be leveled. Several passes may be required over a particular surface before the desired tolerance or level is achieved.

The level of the blade is also determined by the angle of the blade to the support means 14 and 16, and the height of the carrier 12 from the surface to be leveled. The height of the carrier 12 depends on the height of the support means 14 and 16. In order to adjust the height of the blade 20, the height of the carrier in relation to the support means can be adjusted as described below and shown in figure 8. It is also possible to adjust the angle of attack of the blade to the surface to be leveled. This angle can be varied to accommodate surfaces that are hard, or where vegetation exists. In such a case, it may be desirable to have a low angle of attack (that is an acute angle to the surface) to cut into the surface, rather than a scraping motion. For soft sand, it may be desirable to have a high angle of attack (that is an angle 60 degrees to 90 degrees to the surface) so that the material can be scraped across the surface, and more leveling can be accomplished in a single pass. It is therefore important that the angle of the blade is adjustable.

Increasing the angle of the blade with respect to the surface also decreases the depth of cut of the blade for a given pass. It is therefore important that the angle of the blade can be adjusted independently of some height adjustment.

In the embodiment shown in figures 1 and 8, the support means 14 and 16 are wheels 50 on a frame 52. The connection point 70 for the frame 52 to the carrier is offset by a distance perpendicular to the line joining the axles 61 of the wheels. In this way, when the frames 52 are attached in a first orientation as shown in figure 8, the connection point would be above the line of the axles.

When in a second orientation, the connection point 70 would be below a line

between the axles, and thus in the second orientation of the support means, the blade would be lower in reference to the surface to be leveled. In this way, it is easy for the user to quickly adjust the depth of the cut of the blade 20 by swapping the frame 50 from a first orientation of the support means to a second orientation.

In a second embodiment, top support 36 can be moved to central position 38, so that there is a centering force holding the blade 20 in position. In this arrangement, the blade can deflect in either direction depending on the level of force, and thus the apparatus 10 can be pushed or pulled by the user, in either direction.

In use, a user will grasp the handle 24 to move the blade 20 in relation to the ground. The height of the handle determines the angle of the main member 22 to the ground. As the blade 20 is biased to a levelling position 51 to form an angle relative to the of the main member 22, the user can adjust the depth of the blade relative to the frame 50 by tilting the main member 22. It is also possible to adjust the depth of cut by the blade by moving the top support 36 of the adjustment mechanism 25.

It is envisaged that while the user may also raise or lower the angle of the main member to the surface to be leveled, the user will have a preferred height at which to hold the handle, especially as some pushing or pulling is required to move the apparatus over the ground.

Another embodiment of a blade is shown in figures 4 to 7, wherein a blade includes a widened lower portion. This portion on either side of the blade increases the width of the blade, and allows the blade to extend to the full width of the track of the wheels. In this way, edges of a surface can be leveled. In figures 6 and 7, it can be seen that the blade may be attached to the carrier in different orientations. In figure 6, the blade is attached so that the blade is behind the carrier when pulled by a user. In figure 7, the blade is in a position such that it is in front of the carrier when the apparatus is pulled. These arrangements have advantages when the blade is at an acute angle to the surface, in that when pushed, if the blade is at the front, angling the blade by a set amount will

decrease the level of cut compared to if the blade is arranged as shown in figure 7. Thus, it is possible to adjust the blade level for the same angle of blade to surface.

In another embodiment (not shown), it is possible to have the carriers in the form of skids. Skids have a larger surface contact area than wheels and may be more suitable for use in very soft areas, such as sand. Wheels offer advantages in that they have a lower resistance to movement than a skid.

Further, wheels reduce the effect of bumps in the surface effecting the level of the surface. Specifically, if one wheel from a carrier travels over a bump, the centre section of the carrier adjacent the carrier connection only rises half the height of the bump. This has advantages over a skid, as the surface will have smaller imperfections.

Shown in figure 1 is post 60. If additional force is required to push the apparatus across a surface, the user can place their foot on the post to provide an extra push. In another embodiment (not shown), the post may have a supporting wheel or skid to allow the post to be in contact with the ground. This would provide a support post that would allow the main member 22 to be kept a constant angle to the ground, and would result in a more consistent and accurate levelling of the ground.

In figures 9 and 10, a further embodiment is shown, where the support means 116 are connected to the main member 22 via a leg 120. The leg 120 is pivotally connected to a frame 122 of the support means 116, which allows the main member 22 to rotate around a horizontal axis. This rotation of the main member allows the blade 20 to be lifted or lowered relative to the surface.

Wheels 124 on the support means 116 allow the apparatus to be moved easily over large areas.

The biasing mechanism 40 and adjustment mechanism 25 employed in the embodiment shown in figure 1 may also be used in the embodiment shown in figure 9 and 10. Thus, it is still possible to adjust the blade angle, and the force at which the blade deflects, while also adjusting the height of the blade separately.

The leg 120 may be rigidly attached to the main member 22, or there may be some allowance for movement between the main member 22 and leg 120.

Movement between the main member 22 and leg 120 may be around the vertical axis formed by the leg 120, such that the blade is not parallel to a line passing through the front wheels 125. In this way, when the apparatus 101 is moved forward or backward, the blade can move material to the side as it shapes the surface. This is useful in reducing the build up of material in front of the blade 20.

Limited movement between the leg 120 and main member 22 may also be allowable in a rotational manner around a line passing along the main member 22. Thus it may be possible to have one end of the blade 20 further from the surface than the opposite end. This may be useful in creating sloped surface profiles.

A connection means (not shown) between the main member 22 and the frame 120 may include a rubber mount, allowing some degree of movement with a force resisting the twisting of the blade 20. Alternatively, the connection member may be or it may a known type of pinned joint allowing a limited degree of movement. Any known type of connection means may be able to be used In figure 10, a cutaway portion of a frame 127 is shown, detailing the pin 128 upon which the frame 127 is hinged. The pin 128 is mounted to a plate 129, which has a square section channel for insertion into a cross member 130 (best seen in figure 16). The channel may be suitable long so that the track of the device can be increased by mounting the wheels further from the end of a cross member or carrier 12. A fixing means (not shown) may be used to rigidly locate the channel and therefore support means with respect to the carrier 12 or cross member.

In figures 11 and 12, a schematic embodiment is shown of the apparatus in figure 9 and 10 where the leg 120 has been removed and the frame 122 has been attached to the carrier 12 It can be seen that the frame can be swapped between the leg 120 and the carrier 12, to provide alternate means of supporting the blade 20.

It is an advantage to have the carrier mounted to the frame 122 as shown in figure 11 and 12 when more accurate leveling or profiling of a surface is required. This is because movement of the handle 24 and main member 22 cause only small movements in the blade height. Thus it is possible to achieve a high degree of control using this arrangement.

However, where it is desired that the blade have access to more confined spaces, or where a larger degree of movement is desired, the frame 122 can be moved to the position shown in figures 9 and 10. In this position, movements of the handle result in large movements of the blade 20 relative to the surface to be profiled.

In figure 11, the blade 20 is shown at a shallow angle to the surface of the ground. This is useful when the ground below the surface is hard or if the blade is to be used to dig into the surface. In such a case, post 60 can be used to apply extra force onto the blade20 to push the blade 20 into the ground. If the biasing mechanism is used, as shown in figure 2 and 3, then the blade 20 can deflect in response to pressure from the ground. The biasing force can be increased to prevent the blade from deflecting if desired, or a locking mechanism (not shown) can be employed to keep the blade in a fixed position.

One or more wheels 200 may be connected to the end of post 60, to assist in the pushing of the blade 20 into the ground. It is envisaged that the foot of the user may be used to push the post 60, thus reducing the friction if the post comes into contact with the ground.

Figure 12 shows a range of angles 141 over which the blade 20 may move, depending on configuration.

It should be noted that use of the biasing mechanism 25 or adjustment mechanism 25 is optional, and they may be used separately or together, depending on the configuration of the apparatus desired.

In figure 13a, 13b and 13c, three views of a bucket attachment can be seen, wherein the bucket may be used to scrape material, or load material into the bucket for transportation to another location. As the adjustment mechanism

25 allows the carrier 12 to rotate, the angle of the bucket to the ground can be adjusted.

A rake attachment (not shown) can also be used in place of a blade where the rake includes a number of tines for raking the ground.

It is envisaged that the carrier will connect to various implements in the same method as it attaches to the blade.

Figure 14a and be shows one embodiment of a blade 170, with an attachment channel 172. This channel may be used to connect the blade 170 to the carrier 12. Any known method, including screws, snap lock fittings etc. may be employed to attach implements such as the blade 20 and those shown in the present application.

In figure 15 and 16, a connector 181 is shown, which is adapted to allow movement of the main member 22 with respect to the leg 120. The leg 190 in this embodiment includes two supports 182 adapted to attach to axle member 130, which locates wheels 124.

In a further embodiment (not shown), the main member 22 may be connected to a vehicle (not shown) by known means. In this case, the angle of the main member 22 would be fixed relative to the surface to be leveled, and the various methods of adjusting the depth of cut of the blade would be utilised to level the surface.

While the blade and carrier have been defined as separate items, it is envisaged that the blade and carrier may be constructed as a single item.

It is envisaged that the main member 22, handle 24 and carrier 12may all be made from a steel of suitable strength. The blade may be a hardened steel or other material suitable for cutting or profiling the ground.

It is also envisaged that top support 36, as shown in figures 2 and 3, may be located by a cam-lock mechanism (not shown), In simpler embodiments (not shown), the top support 36 may be fixed with respect to the main member 22.

In a further alternative, the biasing member 30 may be a gas strut (not shown).

The skids (not shown) of the support means may have a polyethylene lower sliding surface to reduce friction and provide good wear characteristics.

The wheels shown in the various embodiments may be pivotally located to the frame, such as castors (not shown).