Patent Description:
In agriculture, farming cycles are followed that can roughly be divided into the different steps of land preparation, seed sowing, fertilizing, irrigation, crop growth, and harvesting. Each of these steps is critical to yield optimal crop results and achieve the desired returns on initial investments. Of the listed steps, land preparation is typically further divided into steps of, as necessary, clearing obstructions (e.g. bushes, stones and rocks) and subsequent tillage.

Tilling crumbles and loosens the soil, improves the soil structure and incorporates crop residues and manure into the soil, thus fertilizing the ground. The improved soil structure allows for increased plant root growth, soil aeration and water penetration/filtration. Overall this results in higher yields, better long-term soil fertility, soil moisture retention, and weed management. Tillage can be separated into primary (relatively deep) and secondary (relatively shallow) tillage. In primary tillage, such as ploughing, the soil is turned over such that nutrients come to the surface. In addition to turning up the soil to bring fresh nutrients to the top and depositing plant residue below where it will break down, this process also aerates the earth - enabling it to hold more moisture. Preparing the land to a greater depth produces a rougher surface finish than secondary tillage. Secondary tillage (e.g. seedbed cultivation) breaks up soil clods into smaller masses which might be desirable for small seeds or plants that have minimal clodhandling ability.

Primary tillage, and particularly ploughing, is widely regarded as one of the most effective ways of preventing crop disease, removing weeds, and controlling mice and other pests. In its simplest form the turnplough, also known as the mouldboard plough, includes a variety of plough bodies, which are blades for penetrating and turning over the soil in arrays of adjacent trenches, known as furrows. Modern ploughs typically include a plurality of plough bodies connected to a plough frame such that they are laterally offset manner from each other when the plough is in use. Each plough body is connected to the plough frame via corresponding beams. The plough frame, in turn, is connected to a towing or pushing vehicle via a hitch arranged at a front or back end of the frame.

Depending on the density of the soil, a working depth of the plough bodies can be adjusted. For instance, the plough bodies working depth may be shallow in harder (dense) soils, whereas a deeper working depth may be applied in softer (less dense) soils. The plough bodies can be rigidly attached to the main frame, such that their distance from the main frame remains constant. Accordingly, the working depth of the ploughs are then adjusted by varying the ground clearance of the main frame. If the main frame is brought closer to the ground surface, the ground clearance is reduced, and the plough bodies penetrate deeper into the soil. Similarly, if the main frame is lifted further off the ground, the ground clearance is increased and the plough bodies are lifted, thereby reducing the working depth.

The ground clearance of the main frame may be controlled by one or more depth wheels. The one or more depth wheels may be connected to any part of the main frame such as the rear end of the main frame. An adjustable linkage may be provided between the main frame and the depth wheel to allow for changes in the distance between the depth wheel and the main frame. During ploughing, the depth wheel runs on the ground surface and supports the weight of the plough. If the distance between the depth wheel and the main frame is reduced, then the ground clearance between the main frame and the ground surface reduces accordingly. On the other hand, if the distance between the depth wheel and the main frame is increased, the ground clearance of the main frame increases. As outlined before, changing the main frame's ground clearance results in a variation of the plough body working depth.

Most modern ploughs are of the reversible type, in which the main frame is rotatable by <NUM> degrees (i.e. reversed) with respect to the headstock. A turning cylinder attached to the headstock may be used to rotate (reverse) the plough. During rotation of the main frame, a first set of plough bodies, which was initially arranged below the main frame (first configuration), is transferred to the top of the main frame. At the same time, a second set of plough bodies, which was initially arranged on top of the main frame, is then transferred to a position below the main frame. The reversible plough is then in its second configuration. The main frame may be repeatedly rotated (reversed) between the first and second configuration, particularly during turning manoeuvres on the headlands. Whenever the plough is reversed, the first and second set of plough bodies swap position.

In reversible ploughs, a means of adjusting the working depth of the plough bodies (i.e. the main frame) is required for both configurations of the reversible plough. There are mainly two types of depth control wheels for reversible ploughs. A first type includes a single pivoting depth wheel, which is used in both configurations of the reversible plough. The single pivoting depth wheel has to be moved from one side of the main frame to the other during reversal. This side transfer of the single depth wheel may be achieved by swinging the latter from one side to the other.

A second solution avoids the need for a movement of the depth adjustment wheel from one side to the other. In this second alternative, two separate depth wheels may be fixed to the main frame. A first depth wheel can be arranged on a first side of the main frame and a second depth wheel may be arranged on the second, opposite side of the main frame. Each of the two wheels is then only utilised in one configuration of the plough.

<CIT>) describes a global positioning system (GPS) based soil tillage system. <CIT>) describes a system for monitoring soil conditions within a field may include an implement configured to be traversed across a field.

<CIT>) describes an agricultural implement including at least one row unit having a plurality of support members, each of which is pivotably coupled to an attachment frame or another of the support members to permit vertical pivoting vertical movement of the support members, and a plurality of soil-engaging tools, each of which is coupled to at least one of the support members.

<CIT> describes a plough body position control device which comprises a plough frame, a plough beam pivotally mounted on the plough frame and carrying a plough body (and in which the plough beam is capable of pivoting relative to the plough frame in response to variation in ploughing load applied to the plough body during ploughing, hold-down means for exerting a hold-down force on the plough body during ploughing and which includes a hydraulic piston / cylinder arrangement to control the hold-down force exerted on the plough body: in which the overload control device comprises a pressure source connected to the piston/ cylinder arrangement via a pressure controller, a sensor arranged to monitor the position taken-up by the plough beam relative to the plough frame and to respond to movement of the plough beam with the sensor being arranged to issue corresponding sensor signals, and a processor unit arranged to receive signals from the sensor so as to vary the hold-down force exerted on the plough body in response to variation in ploughing load applied to the plough body.

The solution to the technical problem is achieved by the subjectmatter of independent claims <NUM> and <NUM>, defining per se the invention. Particular embodiments of the invention are defined in the dependent claims.

Advantageously, such an actuator mechanism can be set such that the performance of the agricultural implement is improved. For instance, in examples where the actuator mechanism is a stone trip mechanism for a plough, the stone trip mechanism can be controlled such that it trips at an appropriate reactive force that is experienced by a plough body. In this way: (i) the likelihood of a false trip occurring, when no stone is present, can be reduced; (ii) the likelihood of the ground engaging tool regularly being in a semi-tripped state when it should be in a working position can be reduced; and / or (iii) the likelihood that the ground engaging tool does not trip when a stone is encountered can be reduced.

The previous-trip-event-data may represent trip events (instances when the ground engaging tool has left its working position) in an earlier trip-window of time.

The previous-trip-event-data may comprise one or more of:.

The previous-trip-event-data may comprise:.

The control-data may comprise operational-data, which is representative of one or more operational parameters of the agricultural implement or an associated agricultural vehicle. The operational-data may comprise one or both of:.

The control-data may comprise soil-data, which is representative of one or more characteristics of the soil that is to be worked by the agricultural implement. The soil-data may comprise one or more of:.

The control-data may comprise low-force-location-data, which is representative of known locations in a field that is to be worked by the agricultural implement in which a low bias force is desirable. The controller may be configured to automatically set the level of the bias force that is provided by the actuator mechanism based on (i) the low-force-location-data and (ii) implement-location-data that is representative of a current location of the agricultural implement.

The controller may be configured to set the level of the bias force that is provided by the actuator mechanism such that it does not exceed a maximum-force-value and / or it does not drop below a minimum-force-value.

The actuator mechanism may comprise a cylinder and optionally an accumulator. The accumulator may be configured to maintain a pressure of fluid in the cylinder. The controller may be configured to set a level of fluid pressure in the cylinder based on the control-data.

The controller may be configured to store a location of the ground engaging tool at a time that the ground engaging tool leaves its working position as trip-location-data.

The agricultural implement may include a frame, and a beam that connects the ground engaging tool to the frame. The beam may be movable connected to the frame. For instance, it may be pivotally connected to the frame. The actuator mechanism may be configured to provide a bias force to the beam such that the ground engaging tool is biased towards a working position.

The at least one ground engaging tool may be a plough body.

The agricultural implement may be a reversible plough.

There may be provided an agricultural machinery comprising an agricultural vehicle and any agricultural implement disclosed herein. The agricultural implement may be connected to the front or the rear of the agricultural vehicle.

There may be provided a non-claimed computer program, which when run on a computer, causes the computer to configure any apparatus, including a controller, disclosed herein or perform any method disclosed herein. The computer program may be a software implementation, and the computer may be considered as any appropriate hardware, including a digital signal processor, a microcontroller, and an implementation in read only memory (ROM), erasable programmable read only memory (EPROM) or electronically erasable programmable read only memory (EEPROM), as non-limiting examples. The software may be an assembly program.

The computer program may be provided on a computer readable medium, which may be a physical computer readable medium such as a disc or a memory device, or may be embodied as a transient signal. Such a transient signal may be a network download, including an internet download.

One or more embodiments of the present disclosure will now be described by way of example only, with reference to the accompanying drawings, in which:.

<FIG> show various views of an agricultural implement, particularly a plough <NUM>. As will be described in more detail below, the plough <NUM> shown in <FIG> is a reversible plough.

The plough <NUM> comprises a main frame <NUM>. The main frame <NUM> may be a rectangular or round tube extending between a headstock <NUM> at a front end <NUM> of the plough towards a depth wheel <NUM> at a rear end <NUM> of the plough. The main frame <NUM> supports a variety of ground-engaging tools.

In the example of <FIG>, the ground engaging tools include plough bodies 22a, 22b, 24a, 24b, 26a, 26b, 28a, 28b, 30a, 30b and plough skimmers 32a, 32b, 34a, 34b, 36a, 36b, 38a, 38b, 40a, 40b. A plurality of first ground engaging tools, i.e. plough bodies 22a, 24a, 26a, 28a, 30a and skimmers 32a, 34a, 36a, 38a, and 40a, are arranged on a first side of the main frame <NUM>. In a first configuration of the main frame <NUM>, illustrated in <FIG>, the plurality of first ground engaging tools are arranged below the main frame <NUM>.

A plurality of second ground engaging tools, i.e. plough bodies 22b, 24b, 26b, 28b, 30b and skimmers 32b, 34b, 36b, 38b, and 40b, are arranged on a second side of the main frame <NUM>, opposite to the plurality of first ground engaging tools. In the first configuration of the main frame <NUM>, illustrated in <FIG>, the plurality of second ground engaging tools are arranged above the main frame.

Each of the plough bodies 22a, 22b, 24a, 24b, 26a, 26b, 28a, 28b, 30a, 30b is connected to the main frame <NUM> by means of beams <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. Each of the beams <NUM>, <NUM>, <NUM>, <NUM>, <NUM> has a substantially Y-shaped structure.

A first beam <NUM> supports a first pair of plough bodies 22a, 22b. A second beam <NUM> supports a second pair of plough bodies 24a, 24b. A third beam <NUM> supports a third pair of plough bodies 26a, 26b. A fourth beam <NUM> supports a fourth pair of plough bodies 28a, 28b. A fifth beam <NUM> supports a fifth pair of plough bodies 30a, 30b.

Each of the pairs of plough bodies 22a, 22b, 24a, 24b, 26a, 26b, 28a, 28b, 30a, 30b is designed to create a furrow in the field when the plough is dragged behind or pushed by an agricultural vehicle such as a tractor. It follows that each run of the illustrated plough <NUM> through a field creates five adjacent furrows.

Turning to <FIG>, a typical operation of an agricultural machinery comprising a tractor <NUM> and a plough <NUM> is described. In use, the plough <NUM> is drawn as an attachment (implement) behind an agricultural towing vehicle (e.g. tractor <NUM>). It will be appreciated that it is equivalently feasible to locate the plough <NUM> in front of or both in front of and behind the tractor <NUM>.

<FIG> shows a schematic work area <NUM>, e.g. a crop field, which is divided into a main field <NUM> and headlands <NUM>,<NUM>. A tractor <NUM> draws the plough <NUM> across the main field <NUM> in generally parallel working rows. The working rows are part of the trajectory <NUM> of the tractor <NUM> and typically run in parallel with a long edge of the work area <NUM>. Each working row represents an individual run of the agricultural machinery across the field between headlands <NUM> and <NUM>. As will be described in more detail below, a five-furrow plough, such as the exemplary plough shown in <FIG> creates a total of five furrows per run.

At the end of each run/working row, the tractor <NUM> and plough <NUM> use the upcoming headland <NUM> or <NUM> for turning around, as indicated by trajectory <NUM>. It is known in the art that the soil of the headlands <NUM>, <NUM> is subject to greater levels of soil compaction as it receives more traffic per unit area than the main field <NUM>. In order not to disturb the soil of the headlands <NUM>, <NUM> more than necessary, it is known to lift the ground engaging tools, such as the plough bodies and the skimmers, off the ground into a headland or transfer position, just before the plough <NUM> reaches the headlands <NUM> or <NUM> respectively. Once the tractor <NUM> and the corresponding plough <NUM> have turned on the headland <NUM>, <NUM>, the ground engaging tools of the plough <NUM> are, again, lowered towards an operating position to engage the soil of the main field <NUM>.

In the illustration of <FIG>, the plough <NUM> is working on the main field <NUM> and, therefore, is arranged in the operating position. As the plough <NUM> reaches the border between the headland <NUM>/<NUM> and the main field <NUM>, the plough <NUM> is transferred to a headland/transfer position. It follows that each working row starts with an adjustment of the plough from the transfer position into the operating position and ends with an adjustment of the plough from the operating position into the transfer position.

The plough <NUM> shown in <FIG> is of the fully-mounted type. In fully-mounted ploughs, the weight of the plough is carried exclusively by the tractor when the plough is in its transfer position (on the headlands). In other words, the plough is then exclusively supported by the tractor <NUM> via headstock <NUM> and may be lifted off the ground with a lift cylinder of a tractor linkage.

During the turning movement on the headlands, the plough <NUM> is also reversed. That is, the main frame <NUM> is rotated by <NUM> degrees with respect to the headstock <NUM> to move the plough from a first configuration to a second configuration. In its first configuration shown in <FIG>, the plough <NUM> is set up such that plough bodies 22a, 24a, 26a, 28a, and 30a of each of the pairs are in contact with the soil. This first configuration is shown in <FIG> and sometimes referred to as the "right turning configuration", since the mouldboards of the plough bodies 22a, 24a, 26a, 28a and 30a are arranged to move the soil sideways from left to right when viewed in the direction of travel. In its second configuration (not illustrated), the plough <NUM> is set up such that plough bodies 22b, 24b, 26b, 28b, and 30b of each of the pairs are in contact with the soil. This second configuration is achieved after rotating the main frame by <NUM> degrees, such that the majority of plough bodies are arranged to the right of the tractor (not shown). It follows that the second configuration is also referred to as the "left turning configuration".

Tilling the field with the plough <NUM> in this first configuration provides a first furrow created by the first plough body 22a, a second furrow created by the second plough body 24a, a third furrow created by the third plough body 26a, a fourth furrow created by the fourth plough body 28a, and a fifth furrow created by the fifth plough body 30a. A furrow width is determined by the lateral distance d between the plough bodies 22a, 22b, 24a, 24b, 26a, 26b, 28a, 28b, 30a, 30b, as illustrated in <FIG>.

As the reversible plough <NUM> reaches the end of the first run, the main frame <NUM> is rotated by <NUM> degrees (reversed) with respect to the headstock <NUM>. A turning cylinder (not shown), attached to the headstock <NUM> may be used to rotate (reverse) the plough <NUM>. During rotation of the main frame, the first plurality of plough bodies, e.g. 22a, 24a, 26a, 28a, 30a, are transferred to the top of the plough <NUM>. At the same time, the second plurality of plough bodies e.g. 22b, 24b, 26b, 28b, 30b, which were not in use in the previous run, is then transferred to the lower end of the plough <NUM> and will be submerged in the soil during the next run. The reversible plough is then in its second configuration (not shown).

Executing a second run of the field with the plough <NUM> in this second configuration provides a first furrow created by the sixth plough body 22b, a second furrow created by the seventh plough body 24b, a third furrow created by the eighth plough body 26b, a fourth furrow created by the ninth plough body 28b, and a fifth furrow created by the tenth plough body 30b.

Reversing the plough <NUM> between consecutive runs has the advantage that the plough bodies 22a, 22b, 24a, 24b, 26a, 26b, 28a, 28b, 30a, 30b that engage the soil always face the same side edge of the main field <NUM>, irrespective of the tractor's orientation.

In both configurations of the plough <NUM> the main frame <NUM> is supported by an depth wheel <NUM>. The depth wheel <NUM> is arranged at the back end <NUM> of the plough <NUM>. Since the plough bodies 22a, 22b, 24a, 24b, 26a, 26b, 28a, 28b, 30a, 30b and the skimmers 32a, 32b, 34a, 34b, 36a, 36b, 38a, 38b, 40a, 40b are generally fixed to the main frame via beams <NUM>, <NUM><NUM>, <NUM> and <NUM>, there is no possibility of adjusting the working depth of said ground engaging tools without changing the ground clearance of the main frame <NUM>. To this end, the plough <NUM> shown in <FIG> includes depth wheel <NUM>, which acts as a depth wheel to adjust the ground clearance of the main frame <NUM>. A linkage provided between the depth wheel <NUM> and the main frame <NUM> allows the operator to lift or lower the main frame <NUM> with respect to a ground surface <NUM>. Since the position of the plurality of first and second ground engaging tools is fixed with respect to the main frame <NUM>, any change in the main frame's ground clearance will also affect the working depth of the plurality first and second ground engaging tools. In particular, if the main frame <NUM> is lowered by adjusting the link between the depth wheel <NUM> and the main frame <NUM>, then the working depth of the plurality of first ground engaging tools shown in <FIG> is increased, i.e. the plurality of first ground engaging tools are lowered further into the soil. If, on the other hand, the main frame <NUM> is lifted, then the working depth of the plurality of first ground engaging tools is decreased, i.e. the plurality of first ground engagement tools are pulled out of the soil.

<FIG> illustrate part of a plough that includes a stone trip mechanism for a plough body <NUM> and a beam <NUM>, where the plough body <NUM> is in a working position. <FIG> shows a side view, <FIG> shows a cross-sectional view along the line B-B in <FIG> shows an end view from a distal end of the beam <NUM>. <FIG> are corresponding views that illustrate the stone trip mechanism where the plough body is in a tripped position, as will be described below.

The beam <NUM> connects the plough body <NUM> to a frame (not shown) of a reversible plough. The plough body <NUM> is an example of a first ground engaging tool. These figures show a beam housing <NUM> that provides a mechanical connection between the beam <NUM> and the frame. The beam <NUM> is pivotally connected to the beam housing <NUM>, and therefore is also pivotally connected to the frame. As will be discussed below, the beam housing <NUM> has two hinge points <NUM>, <NUM>, one of which is usable for each of the first and second configurations of the reversible plough.

The beam <NUM> has a substantially Y-shaped structure, which includes a central portion <NUM>, a first beam arm <NUM> and a second beam arm <NUM>. The central portion <NUM> of the beam <NUM> has a proximal end that is pivotally connected to the beam housing <NUM>, and a distal end. The two beam arms <NUM>, <NUM> extend from the distal end of the beam <NUM>. The first beam arm <NUM> connects the plough body <NUM> to the central portion <NUM> of the beam <NUM>. The second beam arm <NUM> connects a second plough body (not shown to assist with the clarity of the illustration) to the central portion <NUM> of the beam <NUM>. The plough body <NUM> can be used to engage the soil and work the field when the reversible plough is in the first configuration. The second plough body (not shown) can be used to engage the soil and work the field when the reversible plough is in the second configuration.

<FIG> also show an actuator mechanism <NUM> that provides a bias force to the beam <NUM> such that the plough body <NUM> is biased towards the working position. The actuator mechanism shown in these figures can also be referred to as a stone trip mechanism. The bias force can be set such that when the plough body <NUM> is being pulled through soil as the plough is working the field, the plough body <NUM> maintains its intended orientation. That is, the bias force applied by the actuator mechanism <NUM> overcomes the reactive force <NUM> experienced by the plough body as it moves through the soil. However, if the plough body <NUM> were to hit a stone or other obstruction buried under the ground, then the additional force that is applied to the plough body by the stone is able to overcome the bias force applied by the actuator mechanism such that the beam <NUM> can pivot about one of the hinge points <NUM>, <NUM>. When the beam <NUM> pivots in this way, the plough body <NUM> moves upwards as shown in <FIG> such that it is above the stone. Therefore, the ploughing operation does not need to stop when a stone is experienced by the plough body <NUM>. Once the plough body <NUM> has passed the stone, the bias force applied by the actuator mechanism returns the plough body <NUM> to its working position.

The actuator mechanism <NUM> includes a cylinder <NUM>, a connection bar <NUM> and a linkage <NUM>. The connection bar <NUM> in this example is mainly located in a cavity that is inside the central portion <NUM> of the beam <NUM>. In this way, the central portion <NUM> of the beam <NUM> can be considered as a sleeve around the connection bar <NUM>. Most of the length of the connection bar <NUM> is visible in the cross-sectional view of <FIG>, and an end of the connection bar <NUM> is also visible in <FIG>. In <FIG>, the connection bar <NUM> is obscured by the cylinder <NUM> and the beam <NUM>.

In this example, the beam <NUM> includes a cylinder mounting region (lug) <NUM> at the proximal end of the central portion <NUM> of the beam <NUM>, and a linkage mounting region (lug) <NUM> at the distal end of the central portion <NUM> of the beam <NUM>. As shown in <FIG>, the cylinder mounting region <NUM> and the linkage mounting region <NUM> extend from opposite sides of the beam <NUM> such that they are laterally offset from each other at opposite ends of the connection bar <NUM>.

A first end of the linkage <NUM> is connected to the linkage mounting region <NUM> at a linkage-beam connection point <NUM>. In this way, the first end of the linkage <NUM> can rotate relative to the beam <NUM>, but cannot experience a translational movement relative to the beam <NUM>. A second end of the linkage <NUM> is connected to a first end of the cylinder <NUM> at a linkage-cylinder connection point <NUM>. A second end of the cylinder <NUM> is connected to the cylinder mounting region <NUM> at a cylinder-beam connection point <NUM>. A first end of the connection bar <NUM> is connected to the beam housing <NUM> (and therefore also the frame) at a bar-frame connection point <NUM>. A second end of the connection bar <NUM> is pivotally connected to a mid-point of the linkage <NUM> at a bar-linkage connection point <NUM>. That is, the bar-linkage connection point <NUM> is between the linkage-beam pivot point <NUM> and the linkage-cylinder connection point <NUM>, along a longitudinal direction of the linkage <NUM>.

In this example, the linkage-beam connection point <NUM>, the linkage-cylinder connection point <NUM>, the cylinder-beam connection point <NUM>, the bar-frame connection point <NUM> and the bar-linkage connection point <NUM> are all pivot points such that the two associated components are rotatable relative to each other. It will be appreciated that in other examples, one or more of these connection points can be rigid connections that do not allow for relative rotational movement, and that any non-linear or rotational movement can be accommodated by other components in the actuator mechanism <NUM>.

An accumulator (not shown in <FIG>) maintains a pressure of the fluid in the cylinder <NUM> when the ground engaging tool <NUM> is in its working position. The pressure in the cylinder <NUM> attempts to push the second end of the linkage <NUM> away from the cylinder mounting region <NUM>, such that it would rotate about the bar-linkage connection point <NUM> and push the linkage-beam pivot point <NUM> back towards the beam housing <NUM>. In this way, the central portion <NUM> of the beam <NUM> is biased along the connection bar such that it abuts the beam housing <NUM>. Therefore, the bias force applied by the cylinder <NUM> acts to maintain the beam <NUM> in its current, working, position with respect to the beam housing <NUM>.

<FIG> illustrate the stone trip mechanism where the plough body <NUM> is in a tripped position. Features of <FIG> that are also shown in <FIG> will be given corresponding reference numbers in the <NUM> series, and will not necessarily be described again. <FIG> also show an accumulator <NUM> that is connected to the cylinder <NUM> by a hose <NUM>, such that it maintains the pressure of the fluid in the cylinder <NUM>.

In <FIG>, the plough body <NUM> has encountered a stone, which has resulted in a high reactive force <NUM> on the plough body <NUM> when it was in its working position. As will be discussed below, this high reactive force <NUM> is larger than the bias force that is provided by the cylinder <NUM> such that the beam <NUM> has pivoted about the first hinge point <NUM>, and the plough body <NUM> has moved out of the way of the stone. More particularly, since the reactive force <NUM> will always be experienced by the lower, in-use, plough body, the beam <NUM> will always pivot about the upper hinge point. Therefore, if the plough were in the second configuration such that the second beam arm <NUM> were facing downwards, the beam <NUM> would pivot about the second hinge point <NUM> (which would be the upper hinge point) upon experiencing a stone.

As the beam <NUM> pivots about first hinge point <NUM>, the second hinge point <NUM> separates and part of the beam <NUM> moves away from the beam housing <NUM>. The first end of the connection bar <NUM> is connected to the beam housing <NUM> at the bar-frame connection point <NUM>, such that the central portion <NUM> of the beam <NUM> moves along the connection bar <NUM> towards the linkage <NUM>. Since the second end of the connection bar <NUM> is connected to a mid-point of the linkage <NUM> at a bar-linkage connection point <NUM>, the linkage <NUM> rotates about the bar-linkage connection point <NUM>. As the linkage <NUM> rotates, the second end of the linkage <NUM> (and therefore also the linkage-cylinder connection point <NUM>) moves closer to the cylinder-beam connection point <NUM>. As the linkage-cylinder connection point <NUM> moves closer to the cylinder-beam connection point <NUM>, the cylinder <NUM> is compressed. In this way, the beam <NUM> is only able to rotate about the first hinge point <NUM> when the reactive force <NUM> on the plough body <NUM> results in a force on the cylinder <NUM> applied by the linkage <NUM>, that is greater than the bias force that is provided by the fluid in the cylinder <NUM>.

<FIG> schematically shows part of an agricultural implement, such as a plough, that includes a controller <NUM> and an actuator mechanism <NUM>. In the same way as described above, the actuator mechanism <NUM> can provide a bias force to a ground engaging tool such that it is biased towards a working position. In some examples, the bias force can be indirectly applied to the ground engaging tool by the actuator mechanism <NUM> applying a force to a beam that is mechanically connected to the ground engaging tool. When the bias force is overcome such that the ground engaging tool leaves it's working position, this will be referred to as a trip event. The actuator mechanism <NUM> can be the same as the one described with reference to <FIG>, <FIG>, or could be different.

The controller <NUM> provides an actuator-control-signal <NUM> to the actuator mechanism <NUM> in order to automatically set the level of the bias force that is provided by the actuator mechanism <NUM>. In this way, the actuator mechanism can be set such that the performance of the agricultural implement is improved. For instance, in examples where the actuator mechanism <NUM> is a stone trip mechanism for a plough, the stone trip mechanism can be controlled such that it trips at an appropriate reactive force that is experienced by the plough body. This can involve charging the accumulator that is shown in <FIG> such that it sets a level of the pressure in the cylinder based on the control-data (<NUM>). In this way: (i) the likelihood of a false trip occurring, when no stone is present, can be reduced; (ii) the likelihood of the ground engaging tool regularly being in a semi-tripped state when it should be in a working position can be reduced; and / or (iii) the likelihood that the ground engaging tool does not trip when a stone is encountered can be reduced.

The controller <NUM> can automatically set the level of the bias force that is provided by the actuator mechanism based on control-data <NUM>. The control-data <NUM> can include previous-trip-event-data, which is representative of one or more earlier instances when the ground engaging tool has left its working position, examples of which are described below. Additionally or alternatively, the control-data <NUM> can include operational-data, soil-data and / or field-data.

The system may include one or more sensors (not shown) that provide the control-data <NUM> to the controller <NUM>. Examples of sensors and associated control-data can include the following. At least some of the sensors can be implemented as inductive, pressure or ultrasonic sensors, as non-limiting examples.

The above instances of previous-trip-event-data can be provided directly by the trip-sensor or can be calculated by the controller <NUM> based on signals received from one or more sensors.

The trip-sensor can monitor the ground engaging tool / beam that is associated with the actuator mechanism that is to be controlled, or it can monitor a different ground engaging tool / beam on the agricultural implement. For instance, one or more of the above examples of previous-trip-event-data can include: (i) same-tool-trip-data that is representative of trip events for the ground engaging tool that is associated with the actuator mechanism that is to be controlled; and / or (ii) neighbouring-tool-trip-data that is representative of trip events for a ground engaging tool that is not associated with the actuator mechanism that is to be controlled. The neighbouring-tool-trip-data does not necessarily relate to an immediate neighbour of the ground engaging tool in question. For example, a neighbouring ground engaging tool can be any ground engaging tool associated with the agricultural implement that is in front of the ground engaging tool in question. In this way, an actuator mechanism can be proactively controlled before the associated ground engaging tool experiences a stone or other obstruction.

Examples of how the controller <NUM> can process the above types of control-data include one or more of:.

It will be appreciated that for each of the above examples, the objective of setting the bias force can be to reduce the number of false trip events (when no stone or other obstacle is encountered), and also to reduce the number of times that the actuator mechanism does not trip when it does encounter a stone. Furthermore, it can be an objective to set the bias force such that the ground engaging tool is in its correct working position when no stone is encountered. That is, the "normal" reactive force that is experienced by the ground engaging tool when no stone is encountered should not result in prolonged trip events.

In some examples, the controller <NUM> can set the level of the bias force that is provided by the actuator mechanism <NUM> such that that it does not exceed a maximum-force-value and / or it does not drop below a minimum-force-value. Especially in relation to the maximum-force-value, this can ensure that the bias force does not get so high that the ground engaging tool breaks when it experiences a stone, rather than causing a trip event.

One or more of the above thresholds may be settable by a user based such that they are appropriate for the field that is being worked by the agricultural implement. For examples where there is a first-threshold and a second-threshold, these thresholds may be the same as each other, or different.

In some examples, a location-determining-system can be associated with the agricultural implement and / or an associated agricultural vehicle. For instance, a plough and / or a tractor that pulls a plough can have a GPS. Optionally, a location (such as GPS coordinates) of the agricultural implement at the time that a trip event starts and / or stops can be stored in memory as trip-location-data. More specifically, in some applications the location of the specific ground engaging tool that experienced the trip event, at the time of the trip event, can be determined and stored in memory as trip-location-data. This can be achieved by providing a location-determining-system with each ground engaging tool. Alternatively, a single location-determining-system can be used for a plurality of ground engaging tools, and a predetermined offset can be applied to the location of the location-determining-system at the time of trip event, based on a received identifier of the ground engaging tool that was tripped. For instance, an offset distance and direction of each ground engaging tool with respect to the location-determining-system can be retrieved from memory based on which of the plurality of ground engaging tools. In some implementations, a controller can apply this offset to the location of the location-determining-system based on a determined direction of travel of the agricultural implement.

The previous-trip-event-data in some examples can include trip-location-data, which is representative of the location of the ground engaging tool at the time of a trip event. Therefore, the trip-location-data can be considered as a location of a stone or other obstruction to ploughing. Optionally, such trip-location-data can be stored in memory so that it can be used for future agricultural operations in the field. In one example, a subsequent method can generate a map of the field in which the agricultural implement was working, which includes identifiers for the locations of stone / obstacles based on the trip-location-data.

Furthermore, in some applications the control-data <NUM>, that is used by the controller <NUM> to set the level of the bias force that is provided by the actuator mechanism <NUM>, can include low-force-location-data, which is representative of known locations in a field that is to be worked by the agricultural implement in which a low bias force is desirable. In some examples, the low-force-location-data can include obstacle-location-data that is representative of known locations of obstacles in the field. The low-force-location-data can include previous-trip-location-data, which is representative of the location of the agricultural implement (and optionally the location of a particular ground engaging tool) at the time of a trip event for a previous agricultural operation (such as a ploughing operation) in the field. That is, the previous-trip-location-data can include trip-location-data that was stored for a previous agricultural operation. In some examples, the low-force-location-data can include field-property-location-data, which can define the locations of one or more of a boundary of the field, a headland, an area of the field that has already been worked (and therefore should not be worked again), or any other region of the filed that should not be processed by the agricultural implement.

In this way, the controller <NUM> can process the low-force-location-data such that it automatically decreases the bias force in a predetermined (virtual) area. Therefore, the ground engaging tool does not need to register a stone (or other obstacle such as a drainage well) by hitting it first, in order for the ground engaging tool to avoid it. The low-force-location-data can be considered as defining virtual forbidden areas in the field. The actuator mechanism <NUM> can be considered as operating as a section control that enables a ground working tool to be extracted from the soil such that it is dragged along on the surface at specific locations in the field, in order to improve the quality of the agricultural operation and / or reduce the likelihood of the agricultural implement being damaged.

In some examples, while the agricultural implement is working a field, the controller <NUM> can also receive implement-location-data that is representative of a current location of the agricultural implement. The implement-location-data can be received from a location-determining-system that is associated with the agricultural implement and / or an associated agricultural vehicle in the same way as described above. The controller <NUM> can process the implement-location-data and the low-force-location-data such that it decreases the bias force based on the low-force-location-data and the implement-location-data. For instance, based on a predetermined relationship between the low-force-location-data and the implement-location-data. An example of such a predetermined relationship is the result of a comparison between (i) the difference between the low-force-location-data and the implement-location-data, and (ii) a distance-threshold. In some examples, the controller <NUM> can determine, and take into account, a direction of travel of the agricultural implement as part of the predetermined relationship to determine whether or not a collision is likely, and therefore whether or not to decrease the bias force. It can be advantageous to decrease the bias force in advance of an expected collision with the stone / obstacle such that the ground engaging tool can trip more easily. This can reduce the likelihood of the ground engaging tool being damaged by the stone / obstacle.

<FIG> illustrates an example embodiment of a method of operating an agricultural implement. The agricultural implement includes a ground engaging tool, a frame, a beam, and an actuator mechanism as described above.

The method is for automatically setting the level of a bias force that is provided by the actuator mechanism based on control-data at step <NUM>. In this example, the control-data includes previous-trip-event-data as described in detail above, and the method includes the optional steps <NUM>, <NUM> of acquiring and determining the previous-trip-event-data.

At step <NUM>, the method involves monitoring the position and / or speed of the ground engaging tool. This can be performed directly or indirectly, for example by monitoring the position and / or speed of a component that is mechanically connected to the ground engaging tool such as the beam. In some examples, it can be more convenient to monitor the position or speed of parts of the beam that are not underground when the ground engaging tool is in its working position. In some examples, the method can determine the position and / or speed of the ground engaging tool by monitoring the position of a cylinder (or other component) of the actuator mechanism.

At step <NUM>, the method involves determining the previous-trip-event-data based on the monitored position or speed of the ground engaging tool. For instance, this can include counting the number of trip events to determine the trip-frequency-data, measuring the duration of the trip events to determine the individual-trip-duration-data or the cumulative-trip-duration-data, and determining a rate of change of the displacement of the ground engaging tool to determine the trip-speed-data.

Claim 1:
An agricultural plough comprising:
a ground engaging tool (<NUM>; <NUM>);
an actuator mechanism (<NUM>; <NUM>; <NUM>) that is configured to provide a bias force to the ground engaging tool (<NUM>; <NUM>) such that it is biased towards a working position; and
a controller (<NUM>) that is configured to automatically set the level of the bias force that is provided by the actuator mechanism (<NUM>; <NUM>; <NUM>) based on control-data (<NUM>), wherein the actuator mechanism (<NUM>; <NUM>; <NUM>) is a stone trip mechanism,
characterized in that the control data (<NUM>) comprises previous-trip-event-data, which is representative of one or more earlier instances when the ground engaging tool (<NUM>; <NUM>) has left its working position.