Patent Description:
It is known to use so-called soil-to-soil packers for the tillage of soil. A soil-to-soil packer comprises a plurality of packer rollers, each roller having a circumferentially ground-contacting part with a substantially U-shaped profile, where the concave side of the U-shape faces the surface of the ground. When such a ground-contacting part is used, soil gets stuck in the U-shape so that it is filled by soil and thus results in the soil being tilled by a surface of the soil.

Soil-to-soil packers, also referred to as U-profile packers, are today very appealing for lighter soils. The large contact surface against the soil ensures bearing capacity which guarantees good depth regulation. When soil acts against soil, an open surface with free evaporation and with good drainage characteristics is provided. A further advantage is that wear is dramatically reduced.

A factor limiting the usage of U-profile packers is the fact that packers of this type have a tendency to contribute to the spread of weeds and pests, such as nematodes, by means of soil stuck in the U-profile being transferred across from one field to another.

A solution to this problem is presented in <CIT>.

Another limiting factor for the usage of U-profile packers is that they do not work very well on heavier soils, nor do they break up clods or recompact the soil at depth very well.

An additional limiting factor is the lack of aggressiveness of the U-profile, i.e. an inferior ability to crush and break up crop residues.

Consequently, there is a need for an improved U-profile packer.

One object is to provide an improved U-profile packer. Specific objects include providing a U-profile packer that reduces the factors limiting the usage of U-profile packers discussed above.

According to a first aspect of the invention, an agricultural implement is provided,
comprising a soil-to-soil packer roller, comprising a plurality of packer roller rings, each having a periphery with a substantially U-shaped profile, where a concave side of the U-shaped profile faces a surface of the ground to be tilled by the agricultural implement, and a scraper arrangement, comprising a scraper tool for each of the packer roller rings. The scraper tools are moveable between a first position in which they are clear of the respective packer roller ring and a second position, in which they extend down into the U-shaped profile of the respective packer roller ring.

It is easy to clear such an agricultural implement between driving the agricultural implement on different fields and thus reduce the risk of spreading for example of seeds from weeds and/or from previous cropping between different fields.

The agricultural implement is also more flexible since it can be driven in different modes, both as an ordinary soil-to-soil packer and as a more aggressive packer with breaking-up functionality.

In the first position, the scraper tools can be located at a first distance, greater than zero, radially outside a radial outer portion of the respective packer roller ring, wherein said distance is preferably greater than <NUM>%, greater than <NUM>% or greater than <NUM>% of a width of the U-shaped profile.

The scraper tools being located at a certain distance from the packer roller ring means that the part of the scraper closest to the packer roller ring is located at said distance.

The U-shaped profile can comprise a central body and a pair of flanges, and the flanges can have substantially the same radial extension from the body.

In the second position, the scraper tools can be located at a second distance, greater than zero, radially inside a radial outer portion of the respective packer roller ring.

The second distance can amount to at least <NUM>% of a minimum radial depth of the U-shaped profile, preferably at least <NUM>% or at least <NUM>%.

"Radial depth" means a distance in a radial direction from the radial outer portion of the flange to the base of the U-shaped profile.

The U-shaped profile can comprise a central body and a pair of flanges, and one of the flanges has a greater radial extension from the body than the second flange.

The flange having a greater radial extension can have a radial extension which is <NUM>-<NUM>% of the radial extension of the other flange, preferably <NUM>-<NUM>%.

The second distance can amount to at least <NUM>% of a minimum radial depth of the U-profile of the packer roller ring, preferably at least <NUM>% or at least <NUM>%.

The second distance can amount to <NUM>-<NUM>% of a difference between the radial extension of the flanges.

At least some of the scraper tools can have a releasably fixable wearing part, which provides at least part of, preferably all of, the engagement of the scraper tool with the U-shaped profile.

The agricultural implement can comprise at least one actuator, for adjusting at least some of, preferably a plurality of, or all of, the scraper tools between said first and second positions.

A set of scraper tools associated with a packer roller can be adjustable by means of an actuator.

"An actuator" means a single actuator or a group of actuators that are jointly controllable, as if they were one actuator.

At least two sets of scraper tools associated with the respective packer rollers can be jointly adjustable by an actuator.

At least some, preferably all, of the scraper tools can be elastically pretensionable against the second position.

The scraper tools are thus provided with the opportunity to spring radially outward in the event that a stone or any other object is stuck too hard in the U-shaped profile.

According to a second aspect of the invention, a method of operating an agricultural implement comprising a soil-to-soil type packer roller is provided. The agricultural implement comprises a packer roller, comprising a plurality of packer roller rings, each having a periphery with a substantially U-shaped profile, where a concave side of the U-shaped profile faces a surface of the ground to be tilled by the agricultural implement, and a scraper arrangement, comprising a scraper tool for each of the packer roller rings. The method comprises positioning the scraper tools in a first position, in which the scraper tools are located outside an engagement position relative to the U-profiles, moving the agricultural implement across a first ground area to be tilled, so that the soil gets stuck in the U-shaped profiles of the packer roller rings, and when the tilling of the first ground area is complete, operating the scraper arrangement, by means of moving it to a second position which is an engagement position for the scraper tools with the U-profiles, and with the scraper arrangement in the second position, moving the agricultural implement across a second ground area, so that substantially all soil stuck in the U-shaped profiles is removed.

"Substantially all" means at least <NUM>%, preferably at least <NUM>% or at least <NUM>%.

The method can comprise positioning the scraper tools in a third position, radially between said first and second positions, so that only a part of the soil stuck in the U-shaped profiles is removed.

In the method, the U-shaped profile can comprise a central body and a pair of flanges, and the third position is located radially inside a radial outer portion of the flanges and radially outside the body.

The third position can be located at a distance corresponding to <NUM>-<NUM>% of the radial extension of the flanges, outside the body. According to one embodiment, this distance can be calculated based on a flange having a minimum radial extension.

The third position can be located radially outside an outer portion of the flanges, preferably at a distance corresponding to <NUM>-<NUM>%, or <NUM>-<NUM>%, of the radial extension of the flanges, outside said outer portion of the flanges. This distance can be calculated based on a flange having a maximum radial extension.

The method can comprise moving the agricultural implement across a second ground area to be tilled, while the scraper tools are located in said third position.

The method can comprise, by means of an actuator, adjusting at least some of, preferably a plurality of, or all of, the scraper tools between said first and second positions.

There is also disclosed an agricultural implement, comprising a packer roller, comprising a plurality of packer roller rings, each having a periphery with a substantially U-shaped profile, where a concave side of the U-shaped profile faces a surface of the ground to be tilled by the agricultural implement, and a scraper arrangement, comprising a scraper tool for each of the packer roller rings. The U-shaped profile comprises a central body and a pair of flanges, one of the flanges has a greater radial extension from the body than the second flange.

There is also disclosed a method of operating an agricultural implement comprising a soil-to-soil type packer. The agricultural implement comprises a packer roller, comprising a plurality of packer roller rings, each having a periphery with a substantially U-shaped profile, where a concave side of the U-shape faces a surface of the ground to be tilled by the agricultural implement, and a scraper arrangement, comprising a scraper tool for each of the packer roller rings. The method comprises moving the scraper tools from a first position, in which the scraper tools do not engage with the U-profiles, to a second position, in which the scraper tools engage with the U-shaped profiles, moving the agricultural implement across a first ground area to be tilled, while at least a part of the soil stuck in the U-shaped profiles is removed.

The U-shaped profile can comprise a central body and a pair of flanges, wherein one of the flanges has a greater radial extension from the body than the second flange. The method can comprise positioning said scraper tools in said second position so that soil stuck in the U-profiles of the packer roller rings is removed within a radial area limited inward by the flange having a smaller radial extension and limited outward by the flange having a greater radial extension, and moving the agricultural implement across a first ground area to be tilled, so that the soil gets stuck in the U-profiles of the packer roller rings.

The method can comprise removing soil so as to expose at least <NUM>%, preferably at least <NUM>% or at least <NUM>%, of the part of said flange with a greater radial extension from the body extending beyond an outer portion of said second flange.

<FIG> shows an agricultural implement <NUM> in the form of a cultivator, which is being pulled by a tractor vehicle, illustrated in the form of a tractor <NUM>.

The agricultural implement <NUM> comprises a plurality of ground-engaging tools, such as levellers, harrow discs and packers. In addition, the agricultural implement may comprise other tools, such as harrow tines, cultivator tines, sowing coulters and other types of sowing arrangements, including row units.

The illustrated agricultural implement <NUM> comprises a plurality of packer rollers <NUM>. One or more packer rollers may be located on a section of the agricultural implement <NUM>, wherein one or more sections may be pivotable or foldable in order to switch the agricultural implement between a working mode and a transport mode.

With reference to <FIG>, a packer roller comprises an axle <NUM>, a pair of attachments 12a, 12b and a plurality of packer roller wheels 100a-100i.

The packer roller wheels 100a-100i may be fixed to the axle <NUM> via spokes <NUM>, which may be welded or attached in any other way to the axle. For example, the spokes may be connected to the axle via a roller bearing, so that each packer roller wheel is individually rotatable about the axle <NUM>. In this case, the axle does not need to be pivotable relative to a frame of the agricultural implement <NUM>.

Each packer roller wheel 100a-100i has a bearing portion, which is the part of the packer roller wheel that bears against the ground. The bearing portion in the particular type of packer normally has a U-shaped profile (marked by 'U' in <FIG>), comprising a body <NUM> and a pair of flanges <NUM>, <NUM>, each extending radially outward from the respective axial end portion of the body <NUM>.

The U-shaped profile, and thus the flanges <NUM>, <NUM>, can be continuous along the entire or greater part of the bearing portion, by means of the flanges extending along the circumferential direction of the packer roller wheel.

As an alternative, the bearing portion may be formed by a plurality of parts which together form the bearing portion, for example, as is shown in <CIT>.

<FIG> schematically show a part of a packer roller wheel <NUM> and a scraper tool <NUM>, which is movable between a first position (<FIG>), in which the scraper tool <NUM> is not located in engagement with the U-shaped profile of the packer roller wheel and a second position (<FIG>), in which the scraper tool <NUM> engages with the U-shaped profile of the packer roller wheel.

The scraper tool <NUM> may have a scraper part, the form of which is substantially complementary to the concave portion of the U-shaped profile.

<FIG> shows how the scraper tool <NUM> is located at a radial distance from the packer roller wheel. The distance may be <NUM>-<NUM>% of the radial depth of the U-shaped profile.

<FIG> shows how the scraper tool <NUM> fully engages with the packer roller wheel <NUM>, so that substantially all soil (with the exception of tolerances and possibly a gap as a result of wear) is scraped off from the U-shaped profile.

Consequently, the engagement with the U-shaped profile may be complete, i.e. the scraper tool <NUM> scrapes against both the body <NUM> and the flanges <NUM>, <NUM> of the U-shaped profile.

The engagement may also be partial, so that the scraper tool <NUM> scrapes against the flanges <NUM>, <NUM>, but not against the body <NUM>, or against the body <NUM> but not against the flanges <NUM>, <NUM>.

"Engagement" means that the scraper tool <NUM> is located radially inside a radial outer portion of the U-shaped profile.

<FIG> illustrates the effect of a packer roller wheel <NUM> with soil that is driven across the ground, i.e. where the scraper tool <NUM> is located in the first position (<FIG>) during driving. As will be seen in <FIG>, the surface of the ground before crossing JYf is relatively coarse with large lumps. However, the surface of the ground after crossing JYe is more even, with smaller lumps but with complete plant residues.

<FIG> shows the effect of a packer roller wheel <NUM> without soil that is driven across the ground, i.e. where the scraper tool <NUM> is located in the second position (<FIG>) during driving. As will be seen in <FIG>, better flattening and crushing/hoeing of plant residues is provided.

<FIG> show an alternative embodiment of the packer roller wheel <NUM>, where the second flange <NUM> has a greater radial extension than the first flange <NUM>. As described with reference to the earlier embodiment, both flanges <NUM>, <NUM> are continuous along the respective bearing portion, or are formed by separate parts, such as in the abovementioned <CIT>.

<FIG> shows the first position, in which the scraper tool <NUM> is located at a radial distance outside the radial outer portion of the packer roller wheel <NUM>, i.e. the larger flange <NUM>. The distance between the scraper tool <NUM> and the radial outer portion of the larger flange <NUM> of the packer roller wheel <NUM> may be approximately <NUM>-<NUM>% of a distance between the radial outer portion of the body <NUM> and of the smaller flange <NUM>.

<FIG> shows the second position, in which the scraper tool <NUM> is in complete engagement with the U-shaped profile, in the same way as in <FIG>.

<FIG> shows the scraper tool <NUM> in a third position, in which the scraper tool <NUM> is in partial engagement with the U-shaped profile. In the example shown, the radial inner portion of the scraper tool <NUM>, viewed in a radial direction, is located between the outer portion of the smaller flange <NUM> and the outer portion of the larger flange <NUM>. Soil that is stuck in the U-shaped profile will hereby be retained at a radial level corresponding to the outer portion of the smaller flange <NUM>. The larger flange <NUM> is exposed however.

<FIG> shows the effect of the third position (<FIG>) when the packer roller wheel <NUM> is driven across the ground. Compaction and breaking-up of lumps of soil is provided at the same time as the exposed flange <NUM> provides improved breaking-up of plant residues. Consequently, a combination of breaking-up soil, hoeing and soil-to-soil rolling is provided.

<FIG> schematically show the distribution of pressure that is achieved by the packer roller wheels on the soil across which the packer roller wheels <NUM> are driven.

<FIG> shows a normal soil-to-soil packer roller wheel (according to <FIG>) with soil and <FIG> shows an asymmetric soil-to-soil packer roller wheel (according to <FIG>) with soil. As can be seen in <FIG>, the asymmetrical packer roller wheel may give rise to a larger ground pressure and thus harder compaction.

The scraper tools <NUM> can be arranged on the agricultural implement <NUM> so that a scraper tool <NUM> is associated with each packer roller wheel <NUM>, 100a-100i.

According to one embodiment, each scraper tool <NUM> can be individually adjustable between its various positions. The adjustment can be divided into a plurality of steps or can be continuous. Adjustment can be made manually or by means of an actuator that can be controlled by the control system of the agricultural implement <NUM>.

Alternatively, a plurality of scraper tools <NUM> may be arranged on a common axle or beam, so that a group of scraper tools <NUM> are jointly adjustable between their various positions. The adjustment can be divided into a plurality of steps or can be continuous. Adjustment can be made manually or by means of an actuator that can be controlled by the control system of the agricultural implement <NUM>.

For example, such an axle or beam can be provided for each packer roller.

A number of different scenarios of use of packer rollers will be described below.

In a first scenario, the agricultural implement <NUM> is driven across the field with the scraper tools <NUM> in the first position (<FIG>, <FIG>). Here the packer acts as a conventional soil-to-soil packer.

After driving, the scraper tools <NUM> are moved into the second position, wherein the agricultural implement <NUM> is driven a shorter distance, preferably on a surface which is less likely to get stuck in the U-shaped profile of the packer roller wheels, such as grass or gravel, wherein the packer <NUM> is engaged with the surface. The profiles are hereby cleared of any soil.

The agricultural implement <NUM> is then reset to a transport mode for moving it into storage or to another field. The transfer of soil between fields is thereby reduced or eliminated.

In a second scenario, the agricultural implement <NUM> is driven on the field with the scraper tools <NUM> in the second position (<FIG>, <FIG>), or in a position between the first and the second position, but engaged with the U-shaped profile. The packer <NUM> then acts as a hoeing packer for hoeing plant residues.

The first and second scenarios can be used with both the packer roller wheel according to <FIG> and with the packer roller wheel according to <FIG>.

In a third scenario, a packer roller wheel according to <FIG> is used, wherein the agricultural implement <NUM> is driven with the scraper tools in the third position according to <FIG>. The soil gets thereby stuck in the inner part of the U-shaped profile; however, one of the flanges <NUM> will be exposed. A hoeing soil-to-soil packer is thus provided.

<FIG> schematically show a scraper arrangement, comprising scraper tools <NUM>, which are pivotable about respective axles <NUM>. An actuator <NUM> can be arranged to act on the axles. The actuator <NUM> can be a rotatable actuator which can act directly on the axle or via a transmission (not shown). Alternatively, the actuator <NUM> can be a linear actuator which can act on the axle <NUM> via a lever (not shown) connected to the axle.

Axles of two or more scraper arrangements can be connected to each other via a link, chain or belt arrangement, so that an actuator can act on two or more scraper arrangements. Each such scraper arrangement can comprise a plurality of scrapers. As described above, each scraper arrangement can act on a, or on part of a, packer roller wheel.

The scraper tools <NUM> can be resilient, for example in order to have the ability to spring back if an object, such as a stone, is stuck too hard in a U-profile. For example, the tool <NUM> can have an arm made of a resilient material, such as spring steel. As an additional alternative, the tool <NUM> can be provided with a spring that pretensions the tool <NUM> against the U-profile.

With reference to <FIG>, the scraper tools can be arranged so that a radial distance Ar between the part of the scraper tool engaging with the U-profile and the base of the U-profile decreases, viewed along the direction of rotation Rr of the wheel during travel of the implement.

Claim 1:
Agricultural implement (<NUM>) comprising:
a soil-to-soil packer roller (<NUM>), comprising a plurality of packer roller rings (<NUM>, 100a, 100b, 100c, 100d, 100e, 100f, <NUM>, <NUM>, 100i), each having a periphery with a substantially U-shaped profile, where a concave side of the U-shaped profile faces a surface of the ground to be tilled by the agricultural implement, and
a scraper arrangement, comprising a scraper tool (<NUM>) for each of the packer roller rings (<NUM>, 100a, 100b, 100c, 100d, 100e, 100f, <NUM>, <NUM>, 100i),
characterized in that
the scraper tools (<NUM>) are moveable between a first position in which they are clear of the respective packer roller ring (<NUM>, 100a, 100b, 100c, 100d, 100e, 100f, <NUM>, <NUM>, 100i) and a second position in which they extend down into the U-shaped profile of the respective packer roller ring (<NUM>, 100a, 100b, 100c, 100d, 100e, 100f, <NUM>, <NUM>, 100i).