WO2004004438A1

WO2004004438A1 - Soil preparation unit

Info

Publication number: WO2004004438A1
Application number: PCT/SE2003/001157
Authority: WO
Inventors: Gert Gilstring; Marcus Ingemarsson
Original assignee: Våderstad-Verken Ab
Priority date: 2002-07-05
Filing date: 2003-07-03
Publication date: 2004-01-15
Also published as: SE0202132D0; SE0202132L; SE523810C2; AU2003248165A1

Abstract

Soil tillage entity comprising at least a first disc entity (6) with a first disc (12) and at least a second disc entity (10) with a second disc (14) for soil tillage, wherein the disc entities (6, 10) are arranged at an agricultural machine orientated in different directions in such a way, that the horizontal components of force (F1, F2; S1, S2) orthogonally against the direction of travel originating from the tilling of the discs in the soil have the opposite direction. According to the invention, the first disc entity (6) and the second disc entity (10) are associated with each other and are intended to be arranged at a frame (16) by means of a suspending device (25) in such a way that the horizontal components of force orthogonally against the direction of travel essentially eliminate each other. Alternatively, the first disc entity (6) and the second disc entity (10) are associated with each other and are intended to be arranged relative to a frame (16) by means of a suspending device (25) in such a way that the horizontal components of force for the resp. disc entity (6, 10) essentially do not cause a turning moment around a vertical axis, the position of which is predetermined.

Description

Soil preparation unit .

BACKGROUND OF THE INVENTION

The present invention relates to a soil tillage entity comprising at least a first disc entity with a first disc and at least a second disc entity with a second disc for soil tillage, wherein the disc entities are arranged at an agricultural machine orientated in different directions in such a way, that the horizontal components of force orthogonally against the direction of travel originating from the tilling of the discs in the soil have the opposite direction.

The invention also relates to such a soil tillage entity.

Such a soil tillage entity and such an agricultural machine are known through WO 00/74464. However, it carries the risk of disposing itself at an angle relative to the direction of travel behind a towing tractor and even of swinging from side to side because of the forces arising when the angled discs cut downwards into the soil.

SUMMARY OF THE INVENTION It is therefore an aim of the present invention to achieve an equilibrium between the lateral forces.

This has been achieved by a soil tillage entity of the initially described type, wherein the first disc entity and the second disc entity are associated with each other and are intended to be arranged at a frame by means of a suspending device in such a way that the horizontal components of force orthogonally against the direction of travel essentially eliminate each other.

The aim has also been achieved by a soil tillage entity of the initially described type wherein the first disc entity and the second disc entity are associated with each other and are intended to be arranged relative to a frame by means of a suspending device in such a way that the horizontal components of force for the respective disc entity essentially do not cause a turning moment around a vertical axis, the position of which is predetermined.

Preferably, the mentioned horizontal components of force have a predetermined angle relative to the direction of travel.

The aim has also been achieved by an agricultural machine of the initially described type, comprising such a soil tillage entity and a suspending device for pivotably suspending the disc entities in the mentioned frame beam.

Hereby is obtained a soil tillage entity and an agricultural machine that are self- stabilising by equilibrium of forces and equilibrium of moments, i.e. primarily follow straight after the towing tractor, regardless of soil type and tillage depth.

The first disc entity and the second disc entity are preferably associated with each other and are intended to be arranged relative to the frame in such a way that equilibrium of moments is essentially achieved around a vertical axis in front of the soil tillage entity in the direction of travel.

The self-stabilisation effect is hereby increased even further.

Advantageously, an any instant essentially lowermost point on at least the first disc entity is freely displaceable along a first line or curve inclined to a horizontal plane fixed relative to the frame, and wherein an at any instant essentially lowermost point on the second disc entity is freely displaceable along a second line or curve, wherein the second disc entity is associated with the mentioned first disc entity in such a way that when the first disc entity is displaced upwards relative to the horizontal plane along the mentioned first line or curve, the second disc entity is displaced along the mentioned second line or curve and wherein when the first disc entity is displaced downwards relative to the horizontal plane along the mentioned first line or curve, the second disc entity is displaced along the mentioned second line or curve in the opposite direction.

In the case of a disc with a non-circular periphery being used, by lowermost point is meant the lowermost point along the conceptual line that connects the radial and peripheral parts of the disc.

The second disc entity is suitably associated with the mentioned first disc entity in such a way that the first disc entity is displaced essentially together with the second disc entity relative to a vertical plane along the direction of travel or vice versa. Hereby is achieved a constant and more even working depth for the one disc entity.

The mentioned second line or curve is preferably mainly parallel to the mentioned horizontal plane. Alternatively, the mentioned first line or curve is mainly parallel to the mentioned horizontal plane. Alternatively the mentioned second line is inclined relative to the horizontal plane, and wherein the mentioned second disc entity is associated with the mentioned first disc entity in such a way that when the first disc entity is displaced upwards relative to the horizontal plane along the mentioned first line or curve, the second disc entity is displaced relative to the horizontal plane along the mentioned second line or curve or vice versa.

The projected displacement of the first disc entity in the horizontal plane is advantageously essentially of the same magnitude as the projected displacement of the second disc entity in the horizontal plane. Alternatively, the projected displacement of the second disc entity in the horizontal plane is proportional to the projected displacement of the first disc entity in the horizontal plane. The projected displacement of the disc entities in the horizontal plane is preferably in proportion to the distance parallel to the direction of travel between the respective disc entity and the towing point of the agricultural machine.

The projected displacement of the second disc entity in the horizontal plane is suitably on the whole equal to the projected displacement of the first disc entity in the horizontal plane multiplied by the ratio of the second disc entity's distance parallel to the direction of travel to the towing point of the agricultural machine and the first disc entity's distance parallel to the direction of travel to the towing point of the agricultural machine.

The extension of the first line or curve and the second line or curve projected along a horizontal plane has preferably an angle relative to a vertical plane along the direction of travel. At least one of the mentioned angles is suitably essentially a right angle. Advantageously, both angles are essentially right angles.

Alternatively, the extension of at least one of the first and second line or curve projected along a horizontal plane has preferably an angle relative to a vertical plane across the direction of travel. At least one of the mentioned angles is suitably essentially a right angle. Advantageously, both angles are essentially right angles.

The first disc entity is essentially arranged at a first disc beam and wherein the second disc entity is arranged at a second disc beam, wherein the mentioned first line or curve extends mainly in a vertical plane parallel to the longitudinal extension of the first disc beam, and wherein the second line or curve extends mainly in a vertical plane essentially in the longitudinal extension of the second disc beam.

The mentioned connection device advantageously comprises a non-detachable connection. The mentioned connection device advantageously comprises a rigid connection, such as a beam. Alternatively, the mentioned connection device comprises a flexible connection, such as a cable. Alternatively, the mentioned connection device is an adjustable connection member, such as a rigging screw or a hydraulic cylinder. Alternatively, the mentioned connection device comprises a pivotable connecting member. Alternatively, the mentioned connection device comprises an adjustable connection member, such as a rigging screw or a hydraulic cylinder, wherein the adjustable connection member is pivotably connected to the disc beams.

The mentioned connection device preferably comprises at least one further connection member, which is pivotable, and is arranged between one of the disc beams and the connection member.

Alternatively, the mentioned connection device comprises two further pivotable connection members arranged between the respective disc beam and the connection member.

The mentioned connection device suitably comprises an arm arranged to have a jointed connection to the frame beam and to be connected between the mentioned pivotable connection members.

DRAWING SUMMARY

In the following, the invention is described in more detail with reference to the attached drawings in which:

Figure 1 illustrates an agricultural machine with a soil tillage entity;

Figures 2a - 2c illustrate a soil tillage entity according to a first embodiment of the invention in different views comprising a fore and a rear row of disc entities; Figures 3a - 3c illustrate the movement of the fore and rear rows of disc entities relative to each other during soil tillage;

Figures 4a - 4c illustrate a soil tillage entity according to a second embodiment;

Figures 5 - 21 illustrate alternative embodiments of the soil tillage entity according to the invention.

DETAILED DESCRIPTION Figure 1 shows an agricultural machine 2. A fore disc beam 4 is provided with disc entities 6, forming a fore row 9, and a rear beam 8 with disc entities 10, forming a rear row 1 1. The disc entities 6 and 10 are respectively provided with rotatable discs 12 and 14. The discs 12, 14 are angled in different directions for interacting soil tillage. The disc beams 4, 8 are suspended on a frame 16 constructed of frame beams 18. The frame is provided with a towing device 20 with a coupling member 22 for connecting to a towing vehicle. The midpoint or towing point of the coupling member is denoted 24.

Different forces act on the discs 12, 14 when they are working in the soil. These can for each respective fore or rear disc 12, 14 be divided up into draught forces Di and D₂, acting backwards; normal forces Ni and N₂, acting upwards and caused by the weight of the agricultural machine 2; opposing lateral forces S| and S₂ caused by the essentially opposing inclined position of the discs 12, 14 relative to the direction of travel. The sum of the respective lateral forces Si and S₂ from the discs 12 of the fore row 9 and the discs 14 of the rear row 11 are denoted Fi and F₂, i.e. Fi = ∑ S_! and F₂ = ∑ S₂.

S] and S₂ and Fi and F₂ are opposing, but are not always of equal magnitude depending on different working depths and the fore discs sometimes working in unfilled soil, i.e. the fore row being exposed to greater resistance than the rear. The forces Si and S₂ and Fi and F₂ have also different distances E| and E₂ to the towing point 24 of the agricultural machine.

All these factors contribute to the prior art agricultural machines provided with interacting disc entities demonstrating imbalance, with angled passage or swinging from side to side as consequences.

Figures 2a - 2c show a first embodiment of the self-stabilising soil tillage entity 32 on an agricultural machine. The soil tillage entity has been provided with a suspending device 25 comprising the fore and rear suspending members 26 and 28 between the disc beams 4 and 8 respectively and the frame beam 18. In addition, the fore disc beam 4 has been connected to the rear disc beam 8 via a connection device 30. The suspending members 26 and 28 have joints 34a, 34b arranged in the direction of travel. The connection device 30, which connects the disc beams 4 and 8 comprises around a horizontal joint 35 pivotable fore and rear spacing members 36, 38 which are in turn connected with a connection member 40 in the form of the rigging screw via joints 41. Thanks to the connection device, the forces Fi and F₂ are mainly not transferred to the frame 16. The lateral forces F] and F₂ are instead essentially taken up by the rigging screw 40.

Figures 3a - 3c show a self-stabilising soil tillage entity, which is based on maintaining equilibrium of forces between the disc entities 6 and 10. The working depth of the discs 12, 14 on the fore and rear rows 9, 11 resp. are denoted 42 and 44 respectively.

Figure 3a shows the discs 12, 14 at the same working depth 42 and 44 resp. The discs 12 cause a first lateral force F_! directed towards the left of the diagram, due to the angle of the discs relative to the direction of travel. The discs 14 have an essentially opposing angle to the discs 12 relative to the direction of travel, which causes a second lateral force F₂ directed towards the right of the diagram. In cases where the discs 12 come into attack in the soil more than discs 14, the lateral forces reach an imbalance, i.e. F] > F₂. The force difference Fi - F₂ displaces both disc beams 4 and 8 to the left of the diagram since these are connected to the connection member 40, see Figure 3b. Then the suspending member 26, because of its actual angle relative to the vertical plane, simultaneously during the movement lifts up the fore disc entities 9 with the discs 12 to a shallower working depth 44, whereby F] decreases. In a corresponding way, the suspending member 28, because of its actual angle relative to the vertical plane, simultaneously during the movement lowers the rear disc entities 11 with the discs 14 to a deeper working depth 42, whereby the force F₂ increases. The movement continues until the force difference have been levelled out and equilibrium achieved.

The movement of the at any instant lowermost points of the discs 12 and 14 has been denoted by Mi and M₂ resp.

The opposite movement is shown in Figure 3 c where the opposite force difference F2 - FI (F2 > FI) has caused an opposing movement, to the right of the diagram which causes in a corresponding way the rear discs to be moved to a shallower working depth and the fore discs to a deeper working depth, which means that F2 decreases and FI increases until equilibrium is achieved.

In this way, the lateral forces on the soil tillage entity are levelled out without the influence of active control by external control loops, i.e. the agricultural machine is self-regulating because of the suspension of the disc entities in the main frame of the implement and the connection to the connection member 40. Hereby, equilibrium of forces accordingly arises between the fore and the rear rows' disc entities 6, 10, i.e. the soil tillage entity is self-stabilising.

It is worth noting that in the positions shown in Figures 3b and 3c, the lateral forces can be in equilibrium, i.e. Fi - F₂. Figures 4a - 4c show how the soil tillage entity becomes self-stabilising through an equilibrium of moments being achieved. In accordance with this second embodiment, an arm 50 is pivotably arranged at a frame beam via a joint 52 in such a way that the arm in the neutral position is parallel to the direction of travel. A connection member 40a in the form of a rigging screw connects the arm with the fore distance member 36, via joints 41a. A further connection member 40b in the form of a rigging screw connects the arm 50 with the rear distance member 38. The neutral position of the arm 50 can of course have an angle relative to the direction of travel.

As discussed above in connection with Fig. 1, the forces Si and S₂ and F] and F₂ have different distances E_t and E₂ resp. to the towing point 24 of the agricultural machine.

This gives a moments equation with equilibrium around towing point 24:

F₂ * E₂ - F, * E, = 0 i.e. F,/F₂ = E₂/E,

A moments equation with equilibrium around joint point 52 gives:

F₂ * K₂ - F, * K, - 0 i.e.

F,/F₂ = K₂/Kι

It hereby follows that with knowledge of the distance Ej and E2, the joint points 41a of the rigging screw 40a are arranged at a distance i and the joint points 41b of the rigging screw 40b are arranged at a distance K from the joint point 52 of the arm 50 (see Figure 4b), with the following relationship:

K,/K₂ = E,/E₂

Thanks to equilibrium of moments being achieved with the soil tillage entity according to the second embodiment, the agricultural machine becomes self- stabilising.

The common pivoting in movement of the disc beams goes to a position of equilibrium. This has been achieved by the projected displacement of the disc entities in the horizontal plane being in proportion to the distance of the resp. disc entity parallel to the direction of travel to a towing point on the agricultural machine.

In accordance with the above relationship, the projected displacement of the second disc entity in the horizontal plane is on the whole equal to the projected displacement of the first disc entity in the horizontal plane multiplied by the ratio of the second disc entity's distance parallel to the direction of travel to the towing point of the agricultural machine and the first disc entity's distance parallel to the direction of travel to the towing point of the agricultural machine.

The equations and relationships presented relating to forces, distances and moments are approximations of the actual conditions and have been created using a simplified theoretical method to explain the fundamental idea of the invention and its function in a pedagogic way. Trigonometric simplifications have been made regarding the actual length of the lever arm. Furthermore, no consideration has been taken of the force effect between frame and disc beams via the suspending members 26 and 28 or of the force effect on the frame of the connection member such as e.g. the joint point 52 of the lever arm 50. The above simplifications means that the optimal embodiment of the connection member can deviate somewhat from that described in the text regarding length and area conditions.

Figure 5 shows a third embodiment of the invention, in accordance with which the connection member 40 comprises a bar, which via joints 41 connects the spacing members 36, 38.

Of course, the rigging screws 40a and 40b according to the second embodiment (see Figures 4a-4c) could in a corresponding way be replaced by a jointed bar.

Figure 6a shows a fourth embodiment of the invention. According to this the connection member 40 comprises a cable. Alternatively, the connection member can consist of a bar.

Figures 6b-6c show a sixth embodiment in which the fore suspending member 26 has in the neutral position a vertical position between joints 34a, 34b. In this case the disc beam 4 on the whole has the ability to move sideways and will therefore take up the same force discussed above, while the disc beam 8 will move sideways and heightways, so it will take up essentially the entire change in lateral force. This means in turn that the working depth for the discs 14 will be altered to a greater degree than is the case for the discs 12.

According to the seventh embodiment shown in Figure 7 the frame has been provided with a pair of tackle blocks 52, over which runs a cable 40. Thanks to the tackle blocks, the forces that act on the spacing members 36, 38 become parallel to the disc beams.

Figure 8 shows an eighth embodiment, according to which the rigging screw 40 in the first embodiment has been replaced by a controllable hydraulic cylinder. With the help of the cylinder the distance between the spacing members 36, 38 can be adjusted.

Figure 9 shows the use of a pair of communicating cylinders 40a, 40b for achievement of equilibrium of moments .

On displacement of the fore disc beam 4 a distance Δ_x)) the cylinder 40a is displaced inwards. The oil volume above the piston will thereby be pressed into the cylinder 40b under its piston, so that it is displaced outwards a distance. The rear disc beam 8 will be hereby displaced a distance Δ_x2. Since the cylinder 40b connects the spacing members 36, 38, it is understood that Δ_x2 > Δ_xι.

Since work done is equal to force times distance, it follows that:

F₂/F, = Δ_xl /Δ_x2 = E,/E₂

In this way, the volumes or areas of the cylinders 40a, 40b can be adapted so that equilibrium of moments is achieved around the towing point 24.

Figure 10 shows a tenth embodiment where a hydraulic cylinder 40a is connected between the spacing member 36 and one of the frame beams 18, and a second hydraulic cylinder 40b is connected between the spacing member 36 and another of the frame beams 18. One piston end of the hydraulic cylinder 40a is connected via a lead 54 to one piston end of the hydraulic cylinder 40b. The hydraulic cylinders are orientated across the direction of travel. Hereby, the force that acts on the spacing members 36, 38 will be directed across the direction of travel. The piston diameter of the pistons in cylinders 40a, 40b can be adapted in such a way that equilibrium of moments is achieved. By use of the same diameter, equilibrium of forces is obtained (compare above). Figures 1 la - 1 lb show an eleventh embodiment, which in contrast to the embodiment shown in Figure 6 has a connection member 40 in the form of a cable. In Figure 1 la, one end of the cable is arranged at a peg 55a at one of the joints 34b of the fore suspending members, i.e. at the connection to the fore beam. The other end of the cable is fixed on a peg 55b on the diagonally disposed rear suspending members 28. For achievement of equilibrium of moments, the length Yj of the suspending member 26 and the position Y₂ of the peg 55b on the suspending member 28 is proportional to the ratio of the distances E_! and E₂.

In Figure 1 lb the cable 40 has instead been arranged at pegs 55a, 55b on the disc beams 4 and 8 resp. diagonally to the direction of travel.

In Figure 12a, a bar 40a and a rigging screw 40b are arranged at the resp. disc beams 4, 8 via pegs 55a, 55b and at lever arms 42a, 42b, which are pivotable around joints 41 a, 41 b connected to the beam 18. The lever arms are jointedly connected with a link 43c. Hereby, self-stabilising is achieved through equilibrium of forces.

Figure 12b shows a variant that is self-stabilising through equilibrium of moments. A rigging screw 40a connects the spacing member 36 and a frame beam 18 via joints 41a. A bar 40b connects in a corresponding way the bar 36 with the frame beam 18 via joints 41b. Lever arms 42a and 42b are arranged at the joints 41a and 41b resp. The lever arms 42a, 42b are each non-detachably connected with a ratchet segment 43a, 43b via a joint 44a, 44b which is non-detachably arranged on the frame beam 18.

The partition diameter of the ratchet segments and the length of the lever arms 42a, 42b is adapted for suitable exchange conditions for the achievement of equilibrium of moments. Of course the rigging screws in Fig. 12a and 12b can be replaced by a bar, and vice versa. They can also be replaced by any other suitable connecting member according to any one of the other embodiments described.

Figure 13 shows a thirteenth embodiment, which corresponds to the second embodiment shown in Figures 4a - 4c, but with the connecting members 40a, 40b in the form of a pair of cables.

Figures 14a and 14b show a fourteenth embodiment, in which the suspending members 26, 28 have angled joints 34a, 34b across the direction of travel. This means that when the disc entities 6 and 10 cut down into the soil and are lifted up or vice versa, the movement will occur along a curve 58a and 58b resp., which depends on the angle of the joints 34a, 34b relative to a vertical plane 57 in the direction of travel.

The curve Mi and M₂ (the projection in Fig. 14b means that the curve is shown as a line, since the curve has constant slope) illustrates the path along which the at any instant lowermost point 59a, 59b on the disc 12 and 14 moves along at combined sideways and heightways displacement.

Figures 15a and 15b show a fifteenth embodiment, in which the suspending members 26, 28 comprise a guide socket 60 non-detachably arranged at the frame beam 18 and a roller 62 that interacts with the guide socket 60. The guide socket is inclined, which causes a movement in the fore and rear disc entities 6, 10 similarly to what has been presented in conjunction with Figures 14a and 14b, except that the movement is wholly linear, i.e. curves 58a, 58b are in this embodiment straight lines.

Figures 16a - 16d show alternative embodiments of the above described embodiments. Figures 17a and 17b show a sixteenth embodiment, in which a plurality of disc beams 61 are arranged along the direction of travel. Each disc beam 61 is suspended via a joint 60 orientated on the whole along the direction of travel. Each disc beam 61 is provided with a fore and rear disc entity 6, 10 with interacting discs 12, 14.

The fore and rear discs 12 and 14 resp. are subjected to lateral forces S| and S₂ when the discs are working in the soil. In the event of imbalance arising so that for example Si > S₂, this is counteracted by the sum of the discs' moments around the joints 60 turning both disc entities in the direction of force Si until equilibrium of forces is achieved.

The joints 60 could be arranged in such a way that they are inclined downwards in the direction of travel. Hereby applies:

S, * H, = S, * H₂

where Hi is the lever arm from Si perpendicular to the joints 60 and H₂ is the lever arm from Si perpendicular to the joints 60. It follows hereby that for achievement of equilibrium of moments for the local equilibrium in the pair of discs that:

F₂/F, = H,/H₂ = E,/E₂ = S₂/S

Figure 18 shows a seventeenth embodiment according to which the fore and rear disc entities 6, 10 are provided with moment arms 62, 64, which are connected by a bar 70 via joints 71. The moment arms 62, 64 are connected to the frame beam 18 via joints 66, 68 parallel to the disc beams 4, 8. This means that when the fore disc entity 6 is lifted, the rear disc entity 10 is pressed down, and vice versa. Of course, the disc beams 4 and 8 can be provided with a plurality of interacting disc entities 12, 14, either rigidly arranged on the resp. disc beam, or separately jointed around axles 66, 68 connected with a bar each. In Figure 18b the bar 70 is replaced by a hydraulic cylinder 70.

Figures 19a - 19d show an embodiment with disc beams 4, 8 non-detachably connected to each other. The frame beam 18 is non-detachably connected to a horizontal axle 99 across the direction of travel, around which the disc beams are journalled in bearings by sheaths 98. When the whole entity of disc beams is displaced along the axle, by the force difference between FI and F2 resp., a simultaneous turning movement is caused by a control device 97. The control device can be provided in different ways, e.g. with a peg 96 on the axle and an angled groove 95 in the sheath 98 (see Fig. 19b) or with an embossed threading 94 on the axle and a corresponding engraved groove in the sheath (see Fig. 19c). A displacement of the disc beams to the left of the diagram means that the fore discs 12 are lifted to a shallower working depth, while the rear discs are lowered to a greater working depth or vice versa, see curves M_t, M₂. In accordance with previously treated embodiments, an equilibrium of forces is created between lateral forces FI and F2.

Figures 20a and 20b show a variant of the embodiment shown in Figures 4a - 4c and Figure 10. In accordance with Figure 20a and 20b, the disc beam 4 is angled at a direction relative to the direction of travel, while the disc beam 8 is angled in the opposite direction and adopts a V-shape. In Figures 20a and 20b, certainly only two embodiments have been shown, but all the above described connection members and suspending members are suitable.

Figure 21 shows a variant with two sets of disc beams 4 and 8, which are arranged in mirror-image V-shapes, and thus form an X-shape. The connection members have been excluded for the sake of clarity, but any one of the above described connection members is applicable. Similarly, all the above described suspending members are applicable. Figure 22a shows an X-shaped soil tillage entity, while Figure 22b shows a row tillage entity with four parallel disc beams. For both embodiments, it is so that one half of the soil tillage entity is a mirror-image across a vertical central plane along the direction of travel of the other half. In both cases, the disc beams on one side are jointedly connected via connecting members 90, 91 with their counterpart on the other side of the mentioned central plane. In accordance with the above, equilibrium of forces and of moments is achieved between the rear disc entities by themselves and between the fore disc entities by themselves.

Prior art agricultural machines with X-shaped soil tillage entities have in themselves a more stabile operation than agricultural machines with V-shaped soil tillage or with parallel disc beams, but become even more self-stabilising with a soil tillage entity according to the invention.

It should be noted that the suspending members and the connection members in the embodiments described above can replace each other in the various embodiments. The cable described above can also be replaced by a chain.

The hydraulic cylinders described above can, unless otherwise specified, be controlled from a control panel on the agricultural machine or in the towing vehicle.

Claims

1. A soil tillage entity comprising at least a first disc entity (6) with a first disc (12) and at least a second disc entity (10) with a second disc (14) for soil tillage, wherein the disc entities (6,10) are arranged at an agricultural machine orientated in different directions in such a way, that the horizontal components of force (F|, F₂; Si, S₂) orthogonally against the direction of travel originating from the tilling of the discs in the soil have the opposite direction, characterised in that the first disc entity (6) and the second disc entity (10) are associated with each other and are intended to be arranged at a frame (16) by means of a suspending device (25) in such a way that the horizontal components of force orthogonally against the direction of travel essentially eliminate each other.

2. A soil tillage entity comprising at least a first disc entity (6) with a first disc (12) and at least a second disc entity (10) with a second disc (14) for soil tillage, wherein the disc entities (6,10) are arranged at an agricultural machine orientated in different directions in such a way, that the horizontal components of force (F F₂; Si, S₂) orthogonally against the direction of travel originating from the tilling of the discs in the soil have the opposite direction, characterised in that the first disc entity (6) and the second disc entity (10) are associated with each other and are intended to be arranged relative to a frame (16) by means of a suspending device (25) in such a way that the horizontal components of force for the respective disc entity (6, 10) essentially do not cause a turning moment around a vertical axis, the position of which is predetermined.

3. A soil tillage entity according to Claim 2, wherein the mentioned horizontal components of force have a predetermined angle relative to the direction of travel.

4. A soil tillage entity according to any one of Claims 1 to 3, wherein an any instant essentially lowermost point on at least the first disc entity (6) is freely displaceable along a first line or curve inclined to a horizontal plane fixed relative to the frame, and wherein an at any instant essentially lowermost point on the second disc entity (10) is freely displaceable along a second line or curve, wherein the second disc entity (10) is associated with the mentioned first disc entity (6) in such a way that when the first disc entity (6) is displaced upwards relative to the horizontal plane along the mentioned first line or curve, the second disc entity (10) is displaced along the mentioned second line or curve and wherein when the first disc entity (6) is displaced downwards relative to the horizontal plane along the mentioned first line or curve, the second disc entity (10) is displaced along the mentioned second line or curve in the opposite direction.

5. A soil tillage entity according to Claim 4, wherein the second disc entity (10) is associated with the mentioned first disc entity (6) in such a way that the first disc entity (6) is displaced essentially together with the second disc entity (10) relative to a vertical plane along the direction of travel.

6. A soil tillage entity according to Claim 4 or 5, wherein the mentioned second line or curve is on the whole parallel to the mentioned horizontal plane.

7. A soil tillage entity according to Claim 5 or 6, wherein the mentioned second line is inclined relative to the horizontal plane, and wherein the mentioned second disc entity (10) is associated with the mentioned first disc entity (6) in such a way that when the first disc entity is displaced upwards relative to the horizontal plane along the mentioned first line or curve, the second disc entity is displaced relative to the horizontal plane along the mentioned second line or curve or vice versa.

8. A soil tillage entity according to any one of Claims 4 - 7, wherein the projected displacement of the first disc entity (6) in the horizontal plane is essentially of the same magnitude as the projected displacement of the second disc entity (10) in the horizontal plane.

9. A soil tillage entity according to any one of Claims 4 - 7, wherein the projected displacement of the second disc entity (10) in the horizontal plane is essentially proportional to the projected displacement of the first disc entity (6) in the horizontal plane.

10. A soil tillage entity according to Claim 9, wherein the projected displacement of the disc entities (6, 10) in the horizontal plane is in proportion to the distance parallel to the direction of travel between the respective disc entity and the towing point (24) of the agricultural machine.

11. A soil tillage entity according to Claim 9 or 10, wherein the projected displacement of the second disc entity (10) in the horizontal plane is on the whole equal to the projected displacement of the first disc entity (6) in the horizontal plane multiplied by the ratio of the second disc entity's (10) distance (E₂) parallel to the direction of travel to the towing point (24) of the agricultural machine and the first disc entity's (6) distance (Ei) parallel to the direction of travel to the towing point (24) of the agricultural machine.

12. A soil tillage entity according to any one of Claims 4 - 11, wherein the respective extension of the first line or curve and the second line or curve projected along a horizontal plane has an angle relative to a vertical plane along the direction of travel.

13. A soil tillage entity according to Claim 12, wherein at least one of the mentioned angles is essentially a right angle.

14. A soil tillage entity according to Claim 12 or 13, wherein both the angles are essentially right angles.

15. A soil tillage entity according to any one of Claims 4 - 11, wherein at least one of the extensions of the first and the second line or curve projected along a horizontal plane has an angle relative to a vertical plane across the direction of travel.

16. A soil tillage entity according to Claim 15, wherein at least one of the mentioned angles is essentially a right angle.

17. A soil tillage entity according to Claim 15 or 16, wherein both the angles are essentially right angles.

18. A soil tillage entity according to any one of Claims 4 - 17, wherein the first disc entity (6) is essentially arranged at a first disc beam (4) and wherein the second disc entity (10) is arranged at a second disc beam (8), wherein the mentioned first line or curve extends mainly in a vertical plane parallel to the longitudinal extension of the first disc beam, and wherein the second line or curve extends mainly in a vertical plane essentially in the longitudinal extension of the second disc beam.

19. A soil tillage entity according to any one of Claims 4 - 18, wherein the connection device (30) comprises a non-detachable connection.

20. A soil tillage entity according to Claim 19, wherein the mentioned connection device (30) comprises a rigid connection, such as a bar.

21. A soil tillage entity according to Claim 19, wherein the mentioned connection device (30) comprises a flexible connection, such as a cable.

22. A soil tillage entity according to Claim 19, wherein the mentioned connection device (30) comprises an adjustable connection member, such as a rigging screw or a hydraulic cylinder.

23. A soil tillage entity according to Claim 19, wherein the mentioned connection device (30) comprises a pivotable connection member.

24. A soil tillage entity according to Claim 19, wherein the mentioned connection device (30) comprises an adjustable connection member, such as a rigging screw or a hydraulic cylinder, wherein the adjustable connection member is pivotably connected to the disc beams.

25. A soil tillage entity according to Claims 23 or 24, wherein the mentioned connection device (30) comprises at least one further connection member, which is pivotable, and is arranged between one of the disc beams and the connection member.

26. A soil tillage entity according to any one of Claims 23 - 25, wherein the mentioned connection device (30) comprises two further pivotable connection members arranged between the resp. disc beam and the connection member.

27. A soil tillage entity according to any one of Claims 23 - 26, wherein the mentioned connection device (30) comprises an arm (50) arranged to have a jointed connection to the frame beam and to be connected between the mentioned pivotable connection members.

28. An agricultural machine comprising a frame beam characterised in that it comprises a soil tillage entity (32) according to any one of the preceding claims and a suspending device (25) for pivotably suspending the disc entities in the mentioned frame beam.

29. An agricultural machine according to Claim 28, wherein the mentioned suspending device (25) comprises at least one suspending member, which is jointed around at least one joint.

30. An agricultural machine according to Claims 28 or 29, wherein the suspending device (25) comprises at least one guide socket (60) for displacing the suspending member.

31. An agricultural machine according to any one of Claims 28 - 30, wherein the mentioned suspending device comprises at least one suspending member which is pivotable around at least one pivot.