Field of the Invention

The present invention relates to a press wheel for an agricultural seeding machine. Background of the Invention Agricultural planters, also known as seed drills, are used to place seed and fertilizer into soil to plant a crop in a paddock. With such planters, a single pass of a paddock is carried out to plough open a furrow in the soil, deposit fertiliser in the furrow, prepare a seed bed by partially filling the furrow with soil to cover the fertiliser, deposit seeds onto the seed bed, and finally close the furrow and apply pressure to the soil using a press wheel in order to ensure adequate contact between the seed and the soil.

In most instances, in order to achieve satisfactory germination of the seeds, it is necessary to place the seeds at a substantially consistent depth beneath the soil surface. This depth is normally quite shallow, typically less than 10cm and on average 2-5cm, but is occasionally required to be deeper depending on the crop being planted.

Each planter assembly normally has a point to engage the soil to open the furrow, which is followed by a scraper to form a seed bed onto which the seed is deposited through a seed tube. Finally, a press wheel travels over the soil surface and engages the sides of the furrow to collapse the furrow and cover the seed with soil. The scraper, seed tube and press wheel are normally mounted on a seeding frame that is moved across the paddock by an agricultural vehicle such as a tractor.

Conventional press wheels are typically of solid wheel-type that apply continuous pressure across an area above the disposed seeds. However, in certain coil conditions, such as in clay-type soils, such press wheels tend to excessively compress the soil across the entire area, which can result in smearing and/or cracking of the soil and thereby hardening of the soil around and above the seeds. Smearing is an effect whereby a press wheel moving over soft and/or moist clay-type soils leaves a smooth surface that will go hard if the soil dries. Such hard soil hampers growth of establishing plants. Summary of Disclosure

According to a first aspect of the present invention, there is provided a press wheel for an agricultural seeding machine, the press wheel comprising:

a wheel hub; and

a plurality of resilient ground contact projections disposed circumferentially around the wheel hub;

the ground contact projections extending outwardly at an acute angle relative to a plane substantially parallel to and disposed generally centrally of the wheel hub from a first end adjacent the plane to a second free end remote from the plane; and

the ground contact projections extending in a direction such that during use each ground contact projection extends in a direction substantially parallel to the ground when the ground contact projection contacts the ground. In an embodiment, the plurality of ground contact projections define a substantially continuous ground contact profile.

In an embodiment, the wheel hub and the ground contact projections are separately formed and connectable to each other.

In an embodiment, the wheel hub comprises first and second hub portions arranged to connect together and to engage with the ground contact projections when the first and second hub portions are connected together. In an embodiment, the ground contact projections are formed of rubber, urethane or plastics material.

In an embodiment, the wheel hub is formed of aluminium material, plastics material, composite material and/or steel material.

In an embodiment, the wheel hub and the ground contact projections are integrally formed.

In an embodiment, the press wheel comprises a tyre portion including the plurality of ground contact projections, the wheel hub and the tyre portion separately formed and connectable to each other. In an embodiment, one of the tyre portion and the hub portions includes at least one channel, and the other of the tyre portion and the hub portions includes at least one rib of complimentary configuration to the at least one channel, the at least one channel and the at least one rib engaging with each other so as to fix the tyre portion to the wheel hub when the first and second hub portions are connected together.

In an embodiment, the tyre portion includes an annular spine and a plurality of ground contact projections extending from the spine. In an embodiment, at least one ground contact projection subtends an acute angle with the plane of approximately 45°.

In an embodiment, the ground contact projections and the annular spine are integrally formed.

In an embodiment, the ground contact projections are separate and connectible to the annular spine.

In an embodiment, at least two ground contact projections disposed on opposite sides of the plane are disposed in a pair such that the ground contact projections of the pair are disposed opposite to and aligned with each other.

In an embodiment, the pair of ground contact projections and the annular spine define a chicken foot configuration.

In an embodiment, the tyre portion is configured such that a substantially continuous ground contact profile is defined by the ground contact projections and the annular spine. In an embodiment, at least two ground contact projections disposed on opposite sides of the plane are offset from and not aligned with each other.

In an embodiment, each ground contact projection tapers outwardly towards the plane. In an embodiment, at least two ground contact projections on opposite sides of the plane extend in the same substantially forward or substantially rearward direction as the press wheel rotates and the ground contact projections contact the ground during use.

In an embodiment, at least one ground contact projection on a first side of the annular spine extends in a substantially forward direction as the press wheel rotates and at least one ground contact projection on a second opposite side of the annular spine extends in a substantially rearward direction as the press wheel rotates.

In an embodiment, all ground contact projections extend rearwardly as the press wheel rotates and the ground contact projections contact the ground during use.

In an embodiment, all ground contact projections extend forwardly as the press wheel rotates and the ground contact projections contact the ground during use.

In an embodiment, each ground contact projection tapers inwardly towards the second free end remote so as to facilitate removal of the ground contact projection from a mould during fabrication of the ground contact projection.

In an embodiment, the ground contact projections include reinforcing material. Brief Description of Drawings

Figure 1 is a diagrammatic perspective view of a press wheel according to an embodiment of the present invention; Figure 2 is a diagrammatic end view of the press wheel shown in Figure 1 ;

Figure 3 is a diagrammatic side view of the press wheel shown in Figures 1 and 2;

Figure 4 is a diagrammatic perspective view of a tyre portion of the press wheel shown in Figures 1 to 3;

Figure 5 is a diagrammatic cross-sectional view of the tyre portion shown in Figure 4 taken along the line V-V in the direction of the arrows;

Figure 6 is a diagrammatic perspective view of a first hub portion of the press wheel shown in Figures 1 to 3; Figure 7 is a diagrammatic perspective view of a second hub portion of the press wheel shown in Figures 1 to 3;

Figures 8a to 8d are diagrammatic views of a foot 28 of the press wheel shown in Figures 1 to 3;

Figure 9 is a diagrammatic perspective view of an alternative press wheel according to an embodiment of the present invention; Figure 10 is a diagrammatic perspective view of an alternative tyre portion of a press wheel according to an embodiment of the present invention;

Figure 1 1 is a diagrammatic cross-sectional view of the tyre portion shown in Figure 10; and

Figure 12 is a diagrammatic view of a foot of the press wheel shown in Figures 10 to 1 1 .

Description of an Embodiment of the Invention

Referring to the Figures, there is shown a press wheel 10 for a seeding machine (not shown). The press wheel 10 includes a wheel hub 12 arranged to be attached during use to a seeding frame (not shown) that is moved relative to a paddock by an agricultural vehicle such as a tractor, the wheel hub 12 including in this example a first hub portion 14 and a second hub portion 16 removably connectable to the first hub portion 14.

The press wheel 10 also includes a tyre portion 18 extending circumferentially around the wheel hub 12. In this example, the tyre portion 18 and the wheel hub 12 are separately formed, and the wheel hub 12 is connected to the tyre portion 18 by engaging the first and second hub portions 14, 16 with each other from opposite sides of the tyre portion 18. However, it will be understood that as an alternative, the wheel hub 12 and the tyre portion may be integrally formed. In the present example, the wheel hub 12 is formed of aluminium, plastics, composite or steel material and the tyre portion is formed of resilient material such as rubber, urethane or plastics material, although any suitable materials are envisaged. Referring to Figures 6 and 7, the first and second hub portions 14, 16 are shown in more detail. The first and second hub portions 14, 16 are substantially similar to each other and therefore similar features are indicated with like reference numerals.

Each of the first and second hub portions 14, 16 includes a rim portion 20 that defines an annular channel 22, and a central hub plate 24 of generally flat configuration. Each annular channel 22 is configured to receive an annular ridge 36a, 36b of the tyre portion 18, as shown in Figure 4, and in this way secure the tyre portion 18 to the wheel hub 12 when the first and second hub portions 14, 16 are connected together.

The hub plate 24 includes fixing apertures 26 that facilitate fixing of the first and second hub portions 14, 16 together, and an axle aperture 27 that facilitates mounting of the press wheel 10 onto a suitable press wheel axle (not shown) disposed on the seeding machine.

Referring to Figures 1 to 5, and in particular Figures 4 and 5, the tyre portion 18 is shown in more detail. The tyre portion 18 includes a plurality of projections, hereinafter referred to as 'feet' 28, each of which extends from an annular spine 30 at an acute angle. The annular spine 30 is disposed in a plane 40 that generally contains the wheel hub 12.

The tyre portion 18 is formed of a material and configured such that the feet 28 are capable of moving resiliently as the feet 28 contact the ground during use. In this way, soil that is disposed between adjacent feet 28 during use is encouraged to be released from the tyre portion 18.

In this example, the feet 28 are disposed in pairs such that each foot 28a is disposed opposite another foot 28b, and the acute angle between a first foot 28a of the pair and the wheel hub 12 is substantially equal to the acute angle between a second foot 28b of the pair and the wheel hub 12. In this way, each pair of feet 28a, 28b define with the annular spine 30 a 'chicken foot' configuration. Without wishing to be bound by theory, it is believed by the inventor that by providing a plurality of spaced ground contact portions in this way, the press wheel 10 performs the function of covering deposited seeds with soil whilst avoiding excessive compression of the soil that can occur with conventional press wheels. As shown in Figures 1 to 5, in this example the feet 28 and the annular spine 30 are integrally formed. As an alternative to the embodiment shown in the Figures, at least two feet 28 disposed on opposite sides of the annular spine 30 may be offset from and not aligned with each other.

As shown more particularly in Figures 2 and 4, the annular spine 30 and the feet 28 define alternating first and second spine regions 32, 34, the first spine regions 32 being relatively large compared to the relatively narrow second spine regions 34.

In this example, the first spine regions 32 are disposed between an opposite pair of feet 28 and in this way a location of potential weakness between the feet 28 and the annular spine 30 is strengthened.

In this example, as best shown in Figure 8, each foot 28 includes an elongate portion 38 that subtends an angle of about 45° with the plane 40 generally containing the annular spine 30 such that the foot 28 extends rearwardly and generally parallel to the ground as the press wheel 10 rotates and the foot 28 contacts the ground during use. A first end 39 of the foot 28 adjacent the annular spine 30 tapers outwardly so as to thereby define the first spine region 32. A free second end 42 of the foot 28 opposite to the first end 39 extends in a direction generally parallel to the plane 40. Figure 8c shows a view of a foot 28 of tyre portion 18 in the direction indicated by arrow A in Figure 8a. Figure 8d shows a view of a foot 28 of tyre portion 18 in the direction indicated by arrow B in Figure 8c.

In the present embodiment, the feet 28 on opposite sides of the annular spine 30 extend in the same substantially rearward direction as the press wheel rotates and the feet contact the ground during use.

However, it will be understood that other variations are possible. For example, at least one foot 28 on a first side of the annular spine 30 may extend in a substantially forward direction as the press wheel rotates and at least one foot 28 on a second opposite side of the annular spine 30 may extend in a substantially rearward direction as the press wheel rotates. Alternatively, all feet 28 may extend forwardly as the press wheel rotates and the feet 28 contact the ground during use. It will be understood that, as shown more particularly in Figures 2 and 8d, the oppositely disposed feet 28a, 28b in each pair of feet 28 taper inwardly slightly and this facilitates easier removal of the feet 28 from a mould during fabrication of the tyre portion 18. The tyre portion 18 is configured such that a substantially continuous ground contact profile is defined, in particular by the feet 28, but also by the annular spine 30. This is achieved because the spine 30 and the feet 28 define a substantially continuous surface, and because each foot 28 is disposed relative to the annular spine 30 and has a slightly curved ground contact profile 44 that is complimentary with the ground contact profiles 44 of the other feet 28. In this example, each 'chicken foot' has a ground contact profile that is approximately 0.00469m ² .

As best shown in Figure 5, the tyre portion 18 includes first and second oppositely disposed annular ridges 36a, 36b, each annular ridge 36 being configured so as to be received in a corresponding annular channel 22 of a respective first or second hub portion 14, 16. It will be understood that the complimentary annular ridges 36 and annular channels 22 serve to lock the wheel hub 12 and tyre portion 18 together when the first and second hub portions 14, 16 are connected together with the annular ridges disposed in the respective annular channels 22.

The tyre portion 18 may be manufactured using any suitable process, for example by moulding so that the annular spine 30 and the feet 28 are integrally formed. During the moulding process, reinforcing material may be included with the moulding material. It will be understood that since the feet 28 are formed of resilient material, such as rubber, they are capable of resiliently flexing as the press wheel 10 contacts the ground during use. As a result, by virtue of the resilient movement of the feet 28, soil material that becomes lodged between adjacent feet 28 is encouraged to dislodge from the press wheel 10.

It will also be understood that since the tyre portion 18 is formed of rubber material, the weight of the press wheel 10 is significantly less that press wheels known hitherto that are formed of solid aluminium or iron material. This becomes significant for seeding machines that have large numbers of planter assemblies and associated press wheels.

The above embodiments are described in relation to a press wheel 10 comprising a tyre portion 18 having resilient feet 28 integral with an annular spine 30. However, it will be understood that other variations are possible. For example, referring to Figure 9, an alternative press wheel 50 is shown that includes resilient feet 52 separately formed from and directly connectable to a wheel hub 54. In this example, the wheel hub 54 is formed of aluminium or steel material and the feet 52 are formed of rubber, urethane or plastics material.

Referring to Figures 10 to 12, an alternative tyre portion 60 is shown. Figure 12 shows a view of a foot 62 of the alternative tyre portion 60 in the direction indicated by arrow C.

The tyre portion 60 is similar to the tyre portion shown in Figures 4 and 5, except that the feet 62 of the alternative tyre portion 60 are of greater thickness than the feet 28 of the tyre portion shown in Figures 4 and 5 for increased strength, as shown more particularly in Figure 12.

It will be understood to persons skilled in the art of the disclosure that many modifications may be made without departing from the spirit and scope of the disclosure. In the claims which follow and in the preceding description of the disclosed boot, boot kit and method, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "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 disclosed boot, boot kit and method.

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