Patent Description:
Packers typically comprise one or more packer rings used for crumbling, breaking down and consolidating ploughed soil prior to delivery of seed. After a plough has passed over the soil, it is beneficial to pack the soil such that the soil will accept water more effectively by improved capillary action. Furthermore, in dry conditions, moisture is retained better if the soil has been packed.

In some conditions, consolidation of the soil can be sufficiently achieved by use of a basic roller which may be pulled beside a plough for example. Rollers typically have a larger dead weight than packer rings. The roller may be additionally weighted with water for example, the additional weight helping to break up clods in the soil and to consolidate the surface to produce a bed for subsequent delivery of seed thereto. The roller may flatten the surface an unintended amount, thereby causing drainage problems. Packer rings on the other hand are typically lighter in weight and if weight is to be applied to the ground/soil, the packer rings can take a temporary weight transfer from the plough to pack the soil.

To achieve better consolidation of the soil, one or more rows of packer or press rings are typically preferred. The rows of rings are pulled over the soil in straight lines, resulting in a good consolidation of the soil and slicing of soil clods remaining after ploughing.

Typically, a frame is pulled behind a piece of farm machinery, such as a tractor, and the frame comprises at least one axle upon which the packer rings are commonly mounted spaced relative to each other. The frame may also comprise other equipment for performing other operations on the soil as is well known in the art.

In some cases each packer ring in the row of packer rings may be interspaced with a tubular sleeve like member which is also configured to interact with the soil to provide some consolidatory effects to the soil. International Patent Application <CIT> discloses such an arrangement.

In some cases the shape of the packer rings has been adapted in attempts to improve their performance. For example, in German patent application <CIT> a plurality of tines is provided to form the packer ring.

Forming the packer rings of individual tines or prongs may provide some advantages. However, the packer rings are subjected to large mechanical loads and often exposed to extreme weather conditions in some regions of the world, therefore excessively complicated arrangements can provide a plurality of weak points in the packer rings which is susceptible to breakage, leading to increased servicing and replacement.

Many prior art soil packer rings comprise a wedge shaped disc formed of two sheet metal rings welded together. Often there is a void between the rings where soil, dirt and water can enter and accumulate. The gathering of such material inside the rings adds weight to the rings and can erode the rings from the inside, particularly at weak points such as at the weld joining the rings. The rings may rust in the void area, particularly since the rings will typically be stored outside in all weather conditions when not in use. It is expensive, time consuming and complicated to change or replace worn packer rings.

Agricultural equipment is typically heavy, and it is often desired to reduce the weight of some equipment, particularly if it is held distant from the vehicle pulling or suspending it. In this regard, it is often desired to reduce the weight of the packer rings, however they must remain sufficiently strong and hard wearing.

Patent document <CIT> discloses a cylindrical roller hub with tines or spokes curved like shovels in a radial plane, so that the axis of the tine-tips is tangential to the hub axis. The tines are formed of two halves of metal plate and welded together to form a hollow inside. The tine ends form surfaces which slant in relation to the roller's radial plane. The tine-tips are pointed. The bridge-pieces joining the tines are preferably of flat steel and act as cutter-blades. The tines can be made of pipes instead of two plates.

Patent document <CIT> discloses a cultivator wheel for use in agricultural machines. It has a hub and tines which project substantially radially from the hub and are provided with pointed outer end portions. These tines are bent out of the central radial plane of the wheel. Portions of the wheel are formed with cutting edges that are inclined circumferentially of the wheel as well as relative to the central radial plane of the same.

Patent document <CIT> discloses a roller with several ring segments on a shaft with the rings having areas which are inclined alternately in opposite directions to the radial plane and to the circumferential direction. The rings have a round or flat cross-section. There are preferably bends between the straight areas of the ring. Imaginary extensions of the bends cut the axis of the ring segments at an angle other than <NUM> degrees. The imaginary extensions of adjoining bends run in opposite directions.

Patent document <CIT> discloses an implement capable of breaking the clods resulting from ploughing and working down these clods, mixing the tilth and compressing it and producing a fine seed bed at the surface. The hub is hexagonal, from which six points radiate, skewed as in wheel spokes. Blades between the points are welded so that they form points. The whole unit is welded together and forms a rigid structure. The points are alternately above and below the central plane of the implement and are typically triangular in form.

Patent document <CIT> discloses a press assembly for an agricultural implement comprising an axle, a plurality of identical tools on the axle and a plurality of spacers each positioned on the axle between respective pairs of adjacent tools. The tools are rollers, press rings or packer wheels. The axle comprises a metal tube with non-circular cross-section. Each tool comprises a wall portion with a central aperture, each aperture being shaped to substantially match the non-circular cross-section of the tube in order to permit each tool to slide into position along the tube and to prevent rotation of each tool on the tube of the axle. Press assemblies of the invention may be particularly applicable for use as a dual press packer where two press assemblies may be arranged one in front of the other with their tools in the form of press rings interleaved.

Document <CIT> discloses a farm roller with a shaft mounted in a frame, on which discs are fastened at a distance from one another, each of which on its outer circumference has an edge, characterized in that each disk has parallel side faces in the vicinity of the shaft and in the region of the alternating troughs has a radially outwardly decreasing width such that, viewed in cross section of the disk through the trough, a surface of the disk rising radially outwards at an angle to the edge of the disk in the trough.

According to a first aspect of the invention, there is provided a packer ring for mounting in a packer and performing work on soil, the packer ring comprising: a central hub for receiving an axle therethrough; a ring portion; and a connecting portion connecting the central hub to the ring portion; wherein the ring portion comprises first and second notches configured to engage the soil in use, characterised in that the ring portion comprises a vertical central plane, and the first notch protrudes outwardly from the vertical centre plane only on a first side of the ring portion and the second notch protrudes outwardly from the vertical central plane only on a second side of the ring portion; wherein the first and second notches and the connecting portion are integrally formed from a single piece of material.

The connecting portion may comprise a plurality of spokes connecting the central hub to the ring portion.

The first and second notches may be arranged in a staggered configuration on the ring portion, such that as the packer ring rotates in use, the first and second notches are delivered to the soil at different times.

The packer ring may further comprise a plurality of additional notches arranged in a staggered configuration on the ring portion such that alternate adjacent notches protrude from alternate sides of the ring portion and such that as the packer ring rotates in use, alternate adjacent notches are delivered to the soil at different times.

The notches may comprise a raised portion between a forward edge and a rearward edge. The notches may be configured to engage the soil at an angle of around <NUM> degrees relative to the horizontal. The notches may be configured to engage the soil at an angle of around <NUM> degrees relative to the horizontal.

According to a second aspect of the invention, there is provided a packer characterised in that the packer comprises a packer ring according to the first aspect of the invention and an axle, wherein the axle is located through the central hub.

The packer may further comprise a plurality of additional packer rings according to the first aspect of the invention, wherein the axle is located through the central hub of each of the plurality of additional packer rings.

According to a third aspect of the invention, there is provided a method of manufacturing a packer ring for mounting in a packer and performing work on soil; the method comprising the steps of: providing a sheet material; cutting a substantially circular shape from the sheet material; cutting a central aperture in the substantially circular shape and cutting at least two additional apertures to provide spokes connecting the central aperture to a ring portion, thereby forming a blank; heating the blank to a sufficient temperature such that the blank can be permanently deformed by a shaping tool; shaping the blank to form a packer ring by sandwiching the blank between two plates of the shaping tool and bringing the plates into engagement with the blank to form at least a first and a second notch on a ring portion of the blank, characterised in that the ring portion comprises a vertical central plane, and the first notch protrudes outwardly from the vertical central plane only on a first side of the ring portion and the second notch protrudes outwardly from the vertical central plane only on a second side of the ring portion.

The method may further comprise a step of hardening the packer ring by flowing a cooling liquid over the packer ring directly after shaping.

The step of shaping may further comprise bringing the plates into engagement with the blank to form rib extrusions on the spokes.

The step of cutting a substantially circular shape from the sheet material and/or the step of cutting a central aperture in the substantially circular shape may be performed by laser cutting the sheet material.

The blank may be heated to between <NUM> and <NUM>,<NUM> degrees Celsius. The blank may be heated to around <NUM> degrees Celsius.

The method may further comprise a step of abrasive blasting the packer ring. The abrasive blasting may be sandblasting.

The method may further comprise a step of attaching a hub into the central aperture. The attachment of the hub may be performed by welding.

Embodiments of the invention will now be described with reference to the following drawings, in which:.

For clarity reasons, some elements may in some of the figures be without reference numerals. A person skilled in the art will understand that the figures are just principal drawings. The relative proportions of individual elements may also be distorted.

<FIG> shows a prior art packer ring <NUM>. The packer ring <NUM> comprises multiple components which are welded together. The packer ring <NUM> comprises a plurality of spokes <NUM>, <NUM> which connect a central aperture <NUM> to a ring portion <NUM>. Typically, each of the spokes <NUM>, <NUM> is welded to the ring portion <NUM>. The ring portion <NUM> has a wedge shaped profile which is formed of first <NUM> and second <NUM> bulb portions welded together. A void <NUM> is formed between the first <NUM> and second <NUM> bulb portions and water, soil and/or dirt may collect within the void <NUM> in use. The process of manufacturing a packer ring <NUM> shown in <FIG> may be temperamental and may be liable to produce many wasted parts due to inaccurate welding or breakages during assembly. Additionally, the packer ring <NUM> may be weak and break easily in use, leading to increased maintenance costs and likelihood of interruptions in service using the packer ring <NUM>.

<FIG> shows a simplified schematic of a packer ring <NUM>. The packer ring is circular in shape and comprises a central aperture <NUM> with first, second and third spokes <NUM>, <NUM>, <NUM> connecting the central aperture <NUM> to a ring portion <NUM>. The packer ring <NUM> is shown firstly without a central hub for clarity purposes.

<FIG> and <FIG> show further details of the packer ring <NUM> shown in <FIG>. It can be seen in <FIG> and <FIG> that the ring portion <NUM> comprises a continuous series of notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> around the entire ring portion <NUM>. In some examples the series of notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may not be continuous and there may be substantially flat connecting portions or other surface features between adjacent notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. Furthermore, it can be seen in <FIG> and <FIG> that in the presently described example the ring portion <NUM> comprises a leading edge <NUM>'. That is to say, the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> are offset from the circumference of the ring portion <NUM> towards the central aperture <NUM>. The purpose of this leading edge <NUM>' will be explained later. Still referring to <FIG> and <FIG>, it can be seen that the spokes <NUM>, <NUM>, <NUM> each comprise ribbed extrusions <NUM>', <NUM>', <NUM>' which are provided to strengthen the spokes <NUM>, <NUM>, <NUM>.

It will be understood that the packer ring <NUM> is configured to be mounted on an axle. Typically, the packer ring <NUM> may be mounted on an axle with a plurality of other packer rings <NUM> in a row. In some examples, there may be multiple rows of packer rings <NUM>. It will be understood that the central aperture <NUM> provides a mounting point for receiving an axle (not shown). In this connection, when the packer ring <NUM> is mounted vertically on a horizontal axle the packer ring <NUM> may be viewed down a vertical central plane <NUM> shown in <FIG>. Alternate notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> protrude from alternate sides of the central plane <NUM>. That is to say, the first, third, and fifth notches <NUM>, <NUM>, <NUM> shown in <FIG> protrude to a first side <NUM> of the central plane <NUM> and the second, fourth and sixth notches <NUM>, <NUM>, <NUM> shown in <FIG> protrude to a second side <NUM> of the central plane <NUM>.

It will be understood that as the central axle (not shown) progresses forward, being pulled by the plough, tractor, or another piece of agricultural machinery, the first, third and fifth notches <NUM>, <NUM>, <NUM> will penetrate the soil to the first side <NUM> of the central plane <NUM> and the second, fourth and sixth notches <NUM>, <NUM>, <NUM> will penetrate the soil to the second side <NUM> of the central plane <NUM>, as the packer ring <NUM> rotates as it travels across the soil.

Referring now to <FIG> which shows a cross-sectional cut through the second and third notches <NUM>, <NUM>, it can be seen that each notch <NUM>, <NUM> is formed of a shell structure to create a convex external surface <NUM>', <NUM>' and a concave internal surface <NUM>", <NUM>".

Referring again to <FIG>, the interaction of the packer ring <NUM> with the soil in use is now explained in greater detail. As the packer ring <NUM> rotates in the direction indicated by arrow A, and travels forward in the direction of arrow B, the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> work the soil to provide agitation, packing, trenching or other work to the soil. In the main, it is the external convex surfaces (<NUM>', <NUM>' in <FIG>) which provide the desired work to the soil. It will be appreciated that the particular form of the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be adapted in some examples, where the packer ring <NUM> is to be used in a particular type of soil and/or a particular climate and/or for a particular purpose such as to improve irrigation or drainage. Just one type of exemplary notch form is shown in the presently described example in the interest of clarity and brevity.

Referring now to the fifth notch <NUM> shown most clearly in <FIG> and <FIG>, it can be seen that each notch comprises a forward edge <NUM> and a rearward edge <NUM>, with a raised portion <NUM> disposed between the forward edge <NUM> and the rearward edge <NUM>. As the packer ring <NUM> progresses such that the fifth notch <NUM> is moved into the soil (not shown), the leading edge <NUM>' of the ring portion <NUM> first engages the soil, thereby splitting the soil such that a portion will be engaged by the fifth notch <NUM> on the first side <NUM> (<FIG>). As the ring portion <NUM> progresses deeper into the soil, the soil will move over the ring portion <NUM> from the leading edge <NUM>' to an inside edge <NUM>". The fifth notch <NUM> is shaped such that the soil is pushed as the raised portion <NUM> progresses through the soil. In the presently described example the soil is pushed downwardly and outwardly from the central plane <NUM>. However, in other examples where the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be shaped differently, the soil may be pushed in a different direction to achieve a different effect.

Referring again to <FIG> it can be seen that in the presently described example the raised portions <NUM> of the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> are configured such that the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> are presented to the soil at an angle <NUM> as the packer ring <NUM> rotates and progresses forwards through the soil. In the presently described example, the angle <NUM> between the each notch <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and the soil when that notch is brought into engagement with the soil is <NUM> degrees relative to the horizontal. In other examples, the angle <NUM> may be between <NUM> degrees and <NUM> degrees relative to the horizontal. In other examples, the angle <NUM> may be between <NUM> degrees and <NUM> degrees. In other examples, the angle <NUM> may be around <NUM> degrees.

Between the raised portion <NUM> and the rearward edge <NUM> of the notch <NUM> and between the rearward edge <NUM> and the inside edge <NUM>" of the ring portion <NUM> there is provided a continuous material, thereby eliminating the collection of soil, water and/or dirt in crevices or voids within the ring portion <NUM>. Again it will be understood that the cross-sectional profile of the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be altered in other examples. As non-limiting examples only, a steeper or shallower inclination between the forward edge <NUM> and the raised portion <NUM> may be provided in some examples, and/or the raised portion <NUM> may be brought closer to the forward edge <NUM> than in the presently described example.

As explained above, when the leading edge <NUM>' of the ring portion <NUM> engages the soil, the soil is split such that some soil is engaged by a notch <NUM>, <NUM>, <NUM> on the first side <NUM> of the packer ring <NUM> and some soil is engaged by a notch <NUM>, <NUM>, <NUM> on the second side <NUM> of the packer ring <NUM>. In this connection, the concave internal surface <NUM>", <NUM>" (shown in <FIG>) may receive some soil. However, the concave internal surfaces <NUM>", <NUM>" allow any gathered soil to be ejected out of the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> as the packer ring <NUM> rotates. The raised portion <NUM> provides movement of the soil on the first side <NUM> of the packer ring <NUM>, and also, due to the shell construction, provides the concave internal surfaces <NUM>", <NUM>" with similarly angled surfaces as the convex external surfaces <NUM>', <NUM>'. In this connection, any soil built up in the concave internal surfaces <NUM>", <NUM>" may easily slide out rather than accumulate and become on the concave internal surfaces <NUM>", <NUM>". The centrifugal force applied to soil at the concave internal surfaces <NUM>", <NUM>" of a notch <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may typically be enough to eject the soil from the concave internal surfaces <NUM>", <NUM>". However, at the end of a packing operation, any stuck soil, dirt or mud remaining in the concave internal surfaces <NUM>", <NUM>" may be easily removed by jet wash or other known cleaning methods. In this connection, although some soil, mud or dirt may still gather in the packer ring <NUM> as described above, the soil will be in an area where it is easy to access and clean, as opposed to being trapped in an inaccessible area. Furthermore, it is likely that if the gathered soil, mud or dirt in the concave internal surfaces <NUM>", <NUM>" is left without being jet washed or otherwise removed, it will typically be removed naturally by exposure of the concave internal surfaces <NUM>", <NUM>" to the surrounding environment and weather. Therefore, even if not cleaned immediately, the soil, mud or dirt is not likely to remain in the packer ring <NUM> for a prolonger period of time, and hence degradation of the packer ring <NUM> by corrosion is mitigated.

Referring now to <FIG>, it can be seen that the packer ring <NUM> further comprises a hub <NUM>' located in the central aperture <NUM> of the packer ring <NUM>, which was omitted from <FIG> for clarity purposes. In this connection, the hub <NUM>' provides an interface for receiving the axle (not shown) upon which the packer ring <NUM> rotates. The hub <NUM>' may be made of the same material as the rest of the packer ring <NUM>, or may be made of a softer material, such that the hub <NUM>' is sacrificially worn as the packer ring <NUM> rotates on the axle. This may provide a wearable part which can be removed and replaced with ease and at lesser expense than replacing the axle or the entire packer ring <NUM>. Regardless of the material and if the hub <NUM>' is configured to be a sacrificial component, the hub <NUM>' provides a tubular connection such that the relatively narrow packer ring <NUM> can be securely and stably mounted on the axle for rotation.

A process of manufacturing the packer ring <NUM> shown in <FIG> is now described with reference to <FIG>. Firstly, a sheet material <NUM> is provided as shown in <FIG>. The sheet material <NUM> may be aluminium, steel, alloy or any other suitable material. The sheet material <NUM> is then cut into a circle to form the ring portion <NUM>. Additionally, the central aperture <NUM> and first, second and third additional apertures <NUM>, <NUM>, <NUM> are cut thereby forming the first, second and third spokes <NUM>, <NUM>, <NUM> as shown in <FIG>. In the presently described example the sheet material <NUM> is cut by a laser. In other examples, other means of cutting the sheet material <NUM> may be used.

The process continues by shaping and hardening the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> on the ring portion <NUM> and the ribbed extrusions <NUM>', <NUM>', <NUM>' on the spokes <NUM>, <NUM>, <NUM>. Firstly, the cut sheet material shown in <FIG> is placed in a shaping and hardening tool (not shown). The shaping and hardening tool comprises first and second plates and is configured such that the cut sheet material can be placed between the plates and then the plates can be brought towards each other to sandwich the cut sheet material between the plates.

To allow the cut sheet material to deform to form the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and ribbed extrusions <NUM>', <NUM>', <NUM>', the cut sheet material is firstly heated to around <NUM> degrees Celsius. In other examples the cut sheet material may firstly be heated to between <NUM> and <NUM>,<NUM> degrees Celsius. In other examples the cut sheet material may be heated to a suitable temperature such that the shaping and hardening tool can plastically deform the cut sheet material.

The first and second plates each comprise protrusions configured to form the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and ribbed extrusions <NUM>', <NUM>', <NUM>' in the cut sheet material. Furthermore, the shaping and hardening tool comprises a cooling means configured to provide a cooling liquid to the packer ring <NUM> directly after the notches <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and ribbed extrusions <NUM>', <NUM>', <NUM>' have been formed. In the presently described example, a flow of water is provided to rapidly cool the packer ring <NUM>. The provision of a cooling liquid flowing over the packer ring <NUM> provides hardening of the packer ring <NUM>. The packer ring <NUM> is then subject to abrasive blasting to provide a desired surface finish and/or remove surface contaminants. In the presently described example, the packer ring <NUM> is sandblasted. It will be understood by a person skilled in the art that a variety of abrasive materials may be used instead of sand in other examples. The hub <NUM>' is then welded into the aperture <NUM> using any known welding technique. The packer ring <NUM> is then optionally cleaned and optionally painted in some examples. The packer ring <NUM> is then ready for mounting on an axle (not shown).

Although in the example shown there are three spokes, in other examples four spokes or any other number of spokes may be provided.

Regarding materials, hardened low-alloy carbon steels typically described in ISO <NUM>-<NUM> and ISO <NUM>-<NUM> are preferred. However, it will be understood that the material used may be selected from a myriad of suitable materials.

Claim 1:
A packer ring (<NUM>) for mounting in a packer and performing work on soil, the packer ring (<NUM>) comprising:
a central hub (<NUM>') for receiving an axle therethrough;
a ring portion (<NUM>); and
a connecting portion (<NUM>, <NUM>, <NUM>) connecting the central hub (<NUM>') to
the ring portion (<NUM>);
wherein the ring portion (<NUM>) comprises first (<NUM>) and second (<NUM>) notches configured to engage the soil in use,
characterised in that the ring portion (<NUM>) comprises a vertical central plane (<NUM>), and the first notch (<NUM>) protrudes outwardly from the vertical central plane (<NUM>) only on a first side (<NUM>) of the ring portion (<NUM>) and the second notch (<NUM>) protrudes outwardly from the vertical central plane (<NUM>) only on a second side (<NUM>) of the ring portion (<NUM>);
wherein the first (<NUM>) and second (<NUM>) notches and the connecting portion (<NUM>, <NUM>, <NUM>) are integrally formed from a single piece of material.