WO1997040660A1

WO1997040660A1 - Agricultural machine

Info

Publication number: WO1997040660A1
Application number: PCT/SE1997/000743
Authority: WO
Inventors: Crister Stark
Original assignee: Crister Stark
Priority date: 1996-05-02
Filing date: 1997-05-02
Publication date: 1997-11-06
Also published as: SE9601678D0; SE506578C2; AU2798297A; EP0959655A1; SE9601678L

Abstract

The present invention relates to an agricultural machine (1), which has front tool elements (14) with vertically symmetrical earth-working tools, such as discs, which are arranged in predetermined positions relative to the driving direction of the machine, and rear tool elements (15) in the form of roller elements for forming a coherent roller. The disc-supporting tool is pivotable in such a way that the long side of the front unit facing towards the driving direction can be directed away from the driving direction, and vice versa, so that essentially two-mirror images of the machine along a central plane in the driving and longitudinal direction are achieved for the purpose of giving an adjusted and even working of the ground.

Description

Agricultural machine

The present invention relates to an agricultural machine comprising first and second earth processing elongated assemblies equipped with tools/working means, which are arranged in predetermined positions relative to the driving direction of the machine.

Increased environmental considerations will in the future, amongst others, be expressed in a requirement that less energy should be consumed per cultivated unit area. Another environmental requirement is also to reduce the leaching of nutritive substances out of the ground, especially during the colder parts of the year. Like¬ wise the aim is to reduce erosion which can be reduced through a large amount of plant remains being left in the ground surface.

With heavy earth (i.e. earth with a high clay content) the requirement of environ¬ mental considerations can hardly be combined with conventional ploughing and earth- working with rotor harrows for several reasons. One reason is energy consumption, as these methods are extremely energy-demanding and therefore involve a large diesel consumption with associated emissions of, amongst others, No_x (and different oxides of carbon). Another reason is the leaching of nutritive substances. When plant remains (first of all straw, chaff, etc.) are well mixed into a relatively shallow layer of earch, which can be repacked, the decomposition process is accelerated. This results in that the contact earth/plant remains becomes good, at the same time as oxygen from the air gains accesss. After that, a so-called inter- mediate crop (e.g. field mustard or rye grass) is sown, which is allowed to grow and develop until the cultivated crop is sown later in the autumn. The intermediate crop and the quick progressive mouldering during this time bind a large amount of, amongst others, the available nitrogen into the ground. In connection with the sowing of the cultivated crop the intermediate crop is broken down and raises together with the now long decomposed straw the humus content of the earth and returns the bound nitrogen and other nutritive substances to the cultivated crop which sets a sood start. In the case that the ground lies unsown during the winter it is a large advantage from a leaching point of view that the ground has a large amount of plant remains in the surface. A possible intermediate crop further improves the capacity of the earth to retain the nitrogen and other nutritive substances. This reduces leaching and the sur- face holds together better than if the earth surface should lie naked as after conven¬ tional ploughing.

In regions with erosion risk it it devastating to leave the earch ploughed. Leaving plant remains in the surface alternatively growing an intermediate crop is therefore of vital importance.

In recent years new sowing techniques have developed, see Swedish Patent Number 458 007, which has a large prevalence because it it quick, exact and extremely less energy-demanding than earlier used techniques. In order to prepare the ground for this sowing technique it is of great importance to process the earth in an optimal way and, moreover, to look at the energy consumption and cost compared with conventional ploughing.

Disc tools in X- or V-shape have been used for many years in agriculture all over the world. Even a now unusual disc tool type with a shaft, which in North America is called a "disc-tiller", was used for many decades on a very large scale all over the world. V-shaped disc tools are in principle best where it is a question of obtaining an even and good working of the surface of the ground, but has a large disadvantage in that the farmer must drive around the field in order to obtain a somewhat flat ground surface. In the case that the tool is driven back and forth, then instead large banks respectively furrows are formed because the tool is not symmetrical.

In order to cope with this problem X-shaped disc tools have been constructed which are symmetrical but even so do not leave the ground surface completely smooth. They have also the disadvantage that the earth does not become completely evenly worked in the middle ofthe tool. In today's situation with powerful tractors the working width often is up to approximately 6 m. As transportation on public roads is a requirement for all agricultural tools, the disc tool has been provided with fold¬ ing up arrangements so that the transport width can be less than 3 m. Because of this the tools have become complicated and relatively expensive.

Disc tillers have certain advantages but also large disadvantages. The foremost dis¬ advantage is that it is necessary to drive around the field, seeing that an extremely strong bank/furrow formation occurs if one drives back and forth. .Another large disadvantage of disc tillers is the powerful oblique drawing. As the discs cut obliquely, the machine wants to wander powerfully sideways.

The object of the present invention is to provide an agricultural machine of the type mentioned in the introduction, which avoids all the above mentioned problems and thereby gives lower energy consumption at the same time as the ground is processed optimally and evenly.

A further object is to provide a machine with which leaching of nutritive substances out of the ground is prevented or reduced.

The objects are achieved through an agricultural machine of the type described in the introduction being given the characteristics which are evident from claim 1.

Preferred embodiments of the agricultural machine according to the invention have the characteristics evident from the subclaims.

The new machine according to the invention has at least one front unit with tools in the shape of disc tools and a rear unit, which is suitably formed of a roller-like construction, which unit leaves the ground surface well evened out and packed, if so desired. An even surface is a requirement so that subsequent operations (sowing, spraying, harvesting, straw-pressing etc.) shall function well. Through at least the front unit turning or twisting in such a way that, for example, the concave sides of the rotors are always directed in the same direction, independent of in which direction the agricultural machine is drawn over a field, the desired even surface is obtained. The front unit with tools in the form of rotors or the like turns or twist, so that the earlier front side ofthe unit in a changed direction of travel is turned to the other side, i.e. from the direction of travel. At the next taming stage the front tool is turned or twisted back to the first position, and so on.

The agricultural machine according to the present invention solves the above problems as the tool independently of the embodiment always can be driven in a V- shape without the drawback of being asymmetric when during turning the tool is adjusted from having been, for example, cutting to the right to cutting to the left, which completely eliminates the formation of banks/furrows. The tendency to oblique drawing is eliminated through the draw bar being able to take up different angular positions at the same time as the rear roller takes up a predetermined angular position in the other direction, which gives proper steering of the machine because of the profile ofthe roller and its considerable weight. The draw bar can be adjusted steplessly sideways in order to balance the machine. The machine can be manufactured in many different embodiments. When large working widths are required, it is suitable to equip the frame beams with one or more links which can be made stiff during transport, an alternative is that the machine is provided with several wheels in order to support the machine and support the weight which can be considerable.

The invention is described more closely in the following with reference to the accompanying drawings which show preferred embodiments.

Figure 1 shows a perspective view of a first embodiment of the agricultural machine according to the invention with a mechanism for preventing oblique drawing during driving. Figure 2 shows a side view of a second embodiment of the agricultural machine according to the invention in a transport position, but without the mechanism against oblique drawing during driving.

Figure 3 shows a side view of the agricultural machine in Fig. 2 in the working position.

Figure 4 shows a plan view of a third embodiment of the agricultural machine according to the invention with a hydraulic arrangement for preventing oblique drawing.

Figure 5 shows a plan view of the agricultural machine in Fig. 4 in a position which is the mirror image of that of Fig. 4.

Figure 6 shows a view from behind of the agricultural machine in the transport position.

Figure 7 shows a view similar to that in Fig. 6 in a position where the roller elements are folded up over the machine in order to diminish the width ofthe machine during transport.

Figure 8 shows a perspective view of a further embodiment of the agricultural machine according to the invention which is drawn by a tractor on a field.

Figure 9 shows a plan view of the agricultural machine in Fig. 8 on a field.

Figure 10 shows the agricultural machine in Fig. 8 and 9 with an accessory for sowing.

Figure 11 shows a partial view of the end of a tool element with a device for scraping the discs. Figure 12 shows a partial view of the end of a disc tool with a guide wheel arrange¬ ment.

Figure 13 shows yet another embodiment of the agricultural machine according to the invention.

Figure 14 shows a view from the rear of the agricultural machine in Fig. 14.

Figure 15 is a partial side view of an embodiment of a support wheel.

Figure 16 is a partial plan view of the embodiment in Fig. 15.

Figure 17 is a partial side view of another embodiment of the support wheel.

Figure 18 is a partial perspective view of another embodiment of the support wheel.

Figure 19 shows a plan view of an agricultural machine according to the invention which is dividable for the mounting of an intermediate tool.

Figure 20 shows a plan view of the agricultural machine in Fig. 4 and 5 in the transport position.

In Fig. 1 an agricultural machine according to the invention is shown for working the ground preferably directly on a harvested field. After harvesting of a field the upper layer ofthe harvested field is processed/broken down and evened by means of the agricultural machine 1 according to the invention, whereafter the prepared field finally can be sown by means of a sowing machine of previously known type. Wε have above described the advantages of an agricultural machine according to the invention. In the drawings similar parts in the different embodiments have been given the same reference numbers. An elongated main beam 5 forms a central part of a triangular-shaped frame 6 comprising further two obliquely positioned side beams 7,8, the front ends of which are joined to the main beam at its front part, and a transverse rear beam 9, at which outer ends the rear ends ofthe side beams are mounted or fastened.

The agricultural machine 1 according to the invention has also a draw bar 10 which is rotatably joined with the frame 6. The angle between the draw bar 10 and the main beam 5 is adjusted by means of a piston- and cylinder unit 11, which at its ends is rotatably joined with the draw bar 10 resp. tlie side beam 7 of the frame 6. A mechanism 12 is activated during the rotation of the draw bar. Fig. 1 shows an embodiment with a first type of mechanism and in Fig. 2-5 a second type of mechanism is shown. The mechanism in Fig. 1 comprises, in addition to the piston and cylinder unit 11, also an essentially parallel with the side beam 8 extending rod 1 la, a rotating link 1 lb, of which one end is hingedly joined with the rod 1 la and which is rotatably mounted on the side beam 8 by means of a pivot pin l ie mounted in bearings in one of a row of holes on the rotating link, and a control arm l id which hingedly joins the other end of the rotating link with a rear tool element. A first rotatable frame beam 13 is arranged under the frame 6 by a suspension arrangement 14 which will be described later. Another rotatable frame beam 15 is arranged behind the first frame beam 13 when seen in the driving direction of the machine.

Agricultural tools are arranged along each ofthe frame beams 13 resp. 15. With the agricultural machine shown in Fig. 1 discs 14 are arranged along the first frame beam and roller elements, joined together to form a a roller 16, along the second frame beam. The front frame beam can even support other elements, such as sym¬ metrical plough elements, under the condition that they perform the same work when the machine takes up its different working positions. The tools are fastened by means of bolted joints 13a, 15a along both the first and second frame beams. Fig. 2 and 3 show from the side the machine in the transport resp. working position. The rotatable suspension between the first frame beam 13 and the frame is formed of a pin 17 mounted on the frame, which is fastened to the main beam 5. A circular- shaped rail 18 is fastened on the underside of the frame 6. In the rail a guide 19 is movably mounted in bearings. By means of this the front tool, the discs, can take up two outer positions which are essentially mirror-inverted relative to each other in the plane of the main beam, i.e. in one position the front discs are pointing from the one side of the machine and in the other position from the opposite side.

The draw bar 10 can be raised and lowered in relation to the tractor by means of a piston and cylinder unit 20. A further piston and cylinder unit 21 is fastened by the cylinder unit to the main beam 5, and its rod part is hingedly joined with an essenti¬ ally V-shaped bracket 22 projecting from the frame beam 15. During activating of the piston and cylinder unit 21 transport wheels 23,24 are lifted from the ground (in the working position) through rotation of the bracket 22 around guide pins 25, which are arranged in holes 26 intended for this purpose in a bracket 27 arranged on the frame.

During driving of the machine in one direction a bank/furrow formation occurs through the effect of the discs. This band/furrow formation is flattened out the next time the machine drives past it through the discs being adjusted to the mirror- imaged position according to the invention. The adjustment of the front disc tool takes place hydraulically, amongst others, by means of the piston and cylinder unit 28a and 28b, where the cylinder 28a is hingedly fastened to the beam 5 and a housing 28c which is movable along the beam and on the underside of which the pm 17 is mounted for trirning of the disc elements 14.

The turning of the draw bar is brought about in the embodiment in Fig. 2-5 by two piston and cylinder units 29 and 30. These units are in turn, via e.g. a master/slave system, connected to two piston and cylinder units 31 resp. 32. When the draw bar 10 is turned in the direction of the arrow 33 the roller unit is rotated on the rear frame beam 15 in the direction of arrow 34 in order to compensate for the oblique drawing of the machine caused by the discs on the frame beam 13. In Fig. 4 and 5 the two mirror-imaged position of the elements of the machine according to the invention are shown.

In Fig. 6 and 7 two transport positions of the machine according to the invention are shown. In Fig. 6 with folded out outer roller sections 35 and 36 and in Fig. 7 with folded up in order to reduce the width of the machine during transport, e.g. on public roads.

Fig. 8 shows another embodiment of an agricultural machine according to the inven¬ tion, where both the tool elements 41,42 are hingedly joined with each other and by means of a metal line 43 and hydraulic piston and cylinder units 44 are shiftable to two essentially mirror-imaged positions. During turning the elements are raised from the ground via the rotatable wheel pairs 45,46. A support wheel 47 and an adjustable link 48 are arranged to regulate the depths of the tools during work in the field.

In Fig. 9 the embodiment of the machine in Fig. 8 is shown from above during work on a field. The agricultural machine 40 according to the invention has been provided with a pre-tool 49 for preworking of the earth. In this case, on each side of the draw bar 50, beams are shown, arranged transversely to the direction of travel, on which cultivator pins have been mounted at essentially mutually equal distances from each other. This pre-tool is naturally so arranged that it is not in the way of the front unit, the tool element 41, during rotation of the same. The two tool-carrying beams can by means of piston and cylinder units be raised to an essentially vertical transport position. This pre-tool is necessary in certain earth conditions and thereby makes more efficient and facilitates the work ofthe following tools.

The shaft of the support wheel 47 should always be essentially horizontal and the wheel should roll in the direction of travel of the tractor during work on the field. T/SE97/00743

10

The wheel must consequently be so adjustable that the angle between the wheel shaft and the extension of the frame beam can be varied and, in order to give the front unit an essentially horizontal direction in the aim of providing an essentially equal working depth along the whole ofthe front unit, the wheel is mounted mov- able up and down at the end of tiie frame beam. Different embodiments of the support/guide wheel will be described later.

In Fig. 10 the agricultural machine according to the embodiment in Fig. 8 and 9 is shown, where a sowing unit 60 has been provided at the rear frame beam 61 which supports the sowing unit. In the drawing the feed arrangement for the seed to be sown has been removed for the sake of clarity. Instead of a sowing arrangement the unit 60 can be a device for working the ground, such as by means of cultivator pins, harrow pins, etc., or a device for spreading or spraying ofthe field.

The sowing unit 60 can, for example, have at a front a row of flat harrow pins 62, which function as a skid plank, whereafter sowing shares 63 are arranged along the two transverse beams and finally a row of wheels 64 in order to close the sowing furrows after the sowing shares. After these tools a row of resilient after-harrow pins 65 can be arranged. This sowing unit 60 is supported on a frame 66. On the rear frame beam 61 a pivot wheel 67 with outer teeth is arranged, whereby a pinion 68, which is driven by a motor (not shown), can rotate the pivot wheel 67 in order to adjust the sewing unit 60 into a predeteπnined position. Two parallel stays 69 and 70 are rotatably arranged on a bracket 71 on the pivot wheel and are also at their other ends rotatably mounted to a stay 72, which in turn is hingedly anchored to a bracket 73 which is fixed to the frame ofthe sowing unit. A hydraulic piston and cylinder unit 74 is arranged between the stay 72 and the frame 66 in order to adjust the position ofthe sowing unit 60. The sowing unit 60 can be rotated up to a position above the second frame beam 61 to a position where it can be placed during transport of the agricultural machine according to the invention. The sowing tool 60 alternatively the following tool can even be mounted in other embodiments of the aεricultural machine such as the others which are shown and described here. In a further development of the invention the control unit 75 of the tractor can be connected to a GPS-receiver according to fig. 10, which reports the position of the machine via satellite 76 and thereby according to predetermined parameters adjusts the control unit 77 of the machine for the adjustment of the cutting angle of the front unit and/or the working depth so that the machine the whole time is optimized for the type of earth alternatively the type of weed in question. The cutting angle and the working depth can be regulated with reference to e.g. the type of earth map which is memorized in the GPS-receiver, for example, during harvesting work of a field. Within predetermined areas on a field the cutting angle and working depth consequently are determined depending on the position of of the machine, which is determined through the GPS-device. Such an earth type map can also within the scope of the invention be followed manually by the driver, who manually controls the cutting angle and/or working depth.

In Fig. 11 an adjustable scraping arrangement 80 is shown for scraping off the rotors of an agricultural machine according to the invention. The scrapers 81 are arranged on both sides of each rotor in order to scrape off the rotor on the correct side de¬ pending on the direction of travel of the agricultural machine. In order to guide the correct scraper into contact against the rotor the scrapers are arranged in a row on the beams 82 resp. 83. These beams are displaceable along the tool along the arrows 84. A V-shaped link 85 is hingedly joined at 85a to the frame beam 86 which holds up the discs. The outer ends of the link 85 is at 87 rotatably joined with each of the beams 82 resp. 83. A piston and cylinder unit 88 is arranged between the frame and the link 85 at a distance from the pivot point on the frame beam.

Fig. 12 shows an embodiment ofthe agricultural machine with two guide/support wheels 89a and 89b, which can be raised and lowered and rotated hydraulically, by means of piston and cylinder units, so that there is always one wheel which is correctly adjusted in the direction of travel.

In Fig. 13 an embodiment ofthe agricultural machine 90 according to the invention is shown, where the machine by means of a piston and cylinder unit 91 can be adjusted into different transport and working positions. A draw bar 92 can in this way be rotated to predetermined angular positions γ relative to the machine. The draw bar 92 is shown in the Figure with solid lines in a transport position for the whole machine. The position shown with dashed lines, where the draw bar has the reference 92A, concerns an intermediate position which can be used as the working position for a certain adjustment of the units relative to the direction of travel. The position shown with dashed lines, where the draw bar has the reference 92B, concerns in this embodiment the outer working position, where the piston and cylinder unit 92C is in its end position. The rear unit is formed of four tool elements 93, in this case roller elements, arranged by the front frame beam, rotatable to pre¬ determined angular positions δ. The rotating suitably takes place by the piston and cylinder unit shown in the drawing. The turning of the machine 90 occurs through the tool element 93 being moved into contact against the frame beam 94, on which the tool or working means of the front unit 95 are arranged - in this case discs. Thereafter the draw bar 92 is moved to a position where the draw bar connector 96 is essentially in alignment with the frame beam 94, and thereafter the whole machine is rotated along the periphery of the four tool elements 93 so that the draw bar with the front unit is moved over to the other side of the frame beam, seen from the ground. Thereafter the draw bar 92 and the tool elements 93 are folded out to the working position. The number of tool elements can naturally vary depending on the width of the machine.

In Fig. 14 both the piston and cylinder units 97 are shown through which activation the machine is turned for driving in the different directions. In this case a piston and cylinder unit 98 is also shown for raising resp. lowering the transport wheels 99.

In another embodiment of the agricultural machine the rotation of the front unit takes place through turning of two separate tool elements which are rotatably arranged on a beam, which is mounted in bearings at its middle on the draw bar. At the outer ends of said beam the elements are rotatably mounted in bearings.

During rotating each element is rotated a half turn, whereafter the beam is adjusted into the right angular position for driving in the other direction. In this case the draw bar is preferably rigidly joined to the rear unit of which the outer ends can be hinged in order to reduce the width during transport.

In a further embodiment ofthe agricultural machine the front unit is mounted on a rigid beam and is rotatable in the plane ofthe ground, whereby the front unit can be swung over and turned through the rear unit being pressed backwardly, for example, through the draw bar being formed telescopically at the rear end and being able to press the rear unit backwardly and to make space for the front unit during the swinging movement. The front unit is rotatably arranged on the draw bar, the rear end of which are rigidly mounted to the rear tool unit on which transport wheels are arranged. The outer ends of both the front and the rear unit can be hinged in order to give the machine a smaller width in the transport position.

In a further embodiment of the agricultural machine 120 at least one end portion of the front unit is rotatable in the plane ofthe ground so that the front unit can be swung over and turned by means ofthe outer portion being swung to the side. The front unit is rotatably arranged on a draw bar the back end of which is rigidly mounted at the rear tool unit on which transport wheels are arranged. The outer ends of both the front and rear unit can be hinged in order to give the machine a smaller width in the transport position.

The different hydraulic functions for the angular adjustment, the movement ofthe wheels and the function ofthe following tool/tools can be simplified for the driver through introducing electrically controlled valves. In a suitable design the hydraulic cylinders ofthe machine are provided with measuring means which report to a control unit which controls the valves according to adjustable parameters. These control functions can also comprise control ofthe scrapers ofthe discs as it can be an inconvenience that they are always in contact with both sides ofthe discs. With dry earth the scrapers are not needed at all wherefore it can be appropriate that they are able to take up an idle position in order to avoid noice and unnecessary wear. In this position the scrapers are held free from contact with the discs. Fig. 15 and 16 illustrate the rotation of the outer guide/support wheel 160 in relation to the position of the front unit 161in the direction of travel (see e.g. the wheel 45 in Fig. 8 or the wheels 88 and 89 Fig. 12). It is important that the wheel 160 is pointing in the direction of travel. Through activating of the piston and cylinder unit 162 of which one end is hinged to the frame beam 163 ofthe front unit 161 and of which the other end is hinged to an arm 164 which is attached to the upper end of a shaft 164 which supports the wheel 160 in a predetermined angle. As is evident from Fig. 18 the shaft 165 is provided with a number of holes in order to be able to regulate the working depth by means of a pin. This height adjustment ofthe front unit is in order to provide an even working depth ofthe front unit, especially large units.

Fig. 17 shows another embodiment ofthe wheel, referenced 170. The wheel is shown here in the two outer positions. The vertically placed shaft 171 is hingedly joined with, on the one hand, two link arms 172 and 173 which are hingedly joined with each other and with a bracket 174, which is rigidly attached to the frame beam 175, on the other hand, an angled hinge arm 176 which at its middle is hingedly fastened to the frame beam at 177 and which at its other end is hingedly joined with a piston and cylinder unit 178, which in its turn is hingedly joined with a bracket 179 on the frame beam 175. Through this design the wheel has a different move- ment between its outer positions.

In Fig. 18 a further embodiment of a support wheel 180 is shown at the front end of the first frame beam, which wheel in general travels in the direction of travel ofthe machine and is so suspended that it can change position through the influence of the piston and cylinder unit in order in every working position to travel in the travelling direction of the machine. The wheel is consequently rotated by means of the cylinder 181 around the shaft 182 (see the double-ended arrow 183) over to the other side ofthe tool. By means of the cylinder 184 the position can be fine- adjusted after rotating so that the wheel has the right travelling position depending on the position of the disc tool. Fig. 19 shows an agricultural machine 190 according to the invention with a splittable frame 191, 192 for the mounting of an intermediate tool 193, such as a cultivator, between the disc unit 194 and the roller element 195. A support wheel 196 similar to that described above with reference to Fig. 21, is mounted in front of the disc unit 194.

In Fig. 20 the agricultural machine in Fig. 4 and 5 is shown in the transport position where the disc unit lies parallel with the direction of travel and two outer sections of the roller element have been folded up over the frame. In this way the whole machine has a minimal width for driving on public roads.

By the fact that the tool can be made extremely effective through its construction and that it can be "inverted or reversed" and thereby driven back and forth without forming banks, an extremely high efficiency is obtained. The machine has an extremely considerable working capacity per kWh of supplied energy and the earth- working therefore becomes very fuel-efficient. That large savings are obtained depends partially on the fact that during conventional ploughing the earth is slid/ pressed under a large pressure against different parts of the plough, with large friction as a consequence. In the described machine the working tools, which are suspended in ball bearings, roll with the earth during the movement of the tool, which naturally gives a much lower friction with considerable savings in pulling force as a consequence.

Another method of establishing a new crop is direct sowing which works well in parts of the world. It is obvious that the method is fuel-efficient but also that it has other disadvantages that are not environmentally friendly.

Direct sowing assumes that the ground surface can be held even, i.e. that tracks which are caused by other operations cannot be removed. This gives a large limita- tion in the case that other driving, e.g. spraying, harvesting, grain transporting, straw-pressing etc., must take place at different points in time when the earth can be wet. These runs then form tracks.

When the straw is left completely open on the surface, it and the remaining stubble form a good environment for mice, insects and fungus cultures. The earth- processing has a strong weed-reducing effect and the broken-down straw quickly moulds. In direct-sowing these effects are lost wherefore direct-sowing requires a heavy investment of growth and mould poisons.

Some further advantages of the agricultural machine according to the invention are given here below:

* Quicker and lower energy consumption and thereby cheaper operation compared with ploughing.

* Leaves well-flattened fields, facilitates followings runs and reduces the risk of "ice-burns" (i.e. standing water which freezes and kills the crop). Removes tracks and other unevenness better than other known systems.

* Permits shortcuts in the cultivation system.

* Requirement-adapted working. (It is only necessary to drive as much as the condi¬ tions require. Under all conditions this method offers less driving than a convention- al system).

* Less wear than with ploughs, and thereby lower cost.

* Together with newly developed sowing technique the system has an extreme effectiveness both concerning results, capacity and economy.

* More secure cultivation and smaller chemical investments than with direct sowing.

In this connection it is important to note that the means for changing of the position or height adjustment of different elements are not shown in detail. Naturally, these means are found in all the designs shown.

Many embodiments of the agricultural machine according to the invention have been described above with reference to the accompanying drawings. Naturally, the features from these embodiments can be combined and modified within the scope of the accompanying claims.

Claims

1. Agricultural machine comprising first and second earth-working elongated units (14, 16) provided with tools/working means, which are arranged in predetermined positions relative to the direction of movement ofthe machine, characterized in that the front unit supports vertically symmetrical tools (14), such as discs, and the rear unit supports roller elements (16) in order to form a coherent roller, and that the front unit is rotatable in such a way that the side facing towards the direction of travel of the front unit is directed away from the direction of travel, or vice versa, so that in the main two mirror-images along a plane in the longitudinal direction of the machine are produced with the purpose of giving an adjusted and even working of the ground.

2. Agricultural machine comprising first and second earth-working elongated units ( 14, 16) provided with tools/working means, which are aπanged in predetermined positions relative to the direction of movement ofthe machine, characterized in that the front unit supports vertically symmetrical tools (14), such as discs, and the rear unit supports roller elements (16) in order to form a coherent roller in the direction of travel, and that both units are rotatable along a longitudinal shaft in such a way that the side of the front unit facing towards the direction of travel is directed away from the direction of travel, or vice versa, so that in the main two mirror images along a plane in the longitudinal direction of the machine are produced with the purpose of giving an adjusted and even working ofthe ground.

3. Agricultural machine according to Claim 1 or 2, characterized in that transport wheels (23,24) are arranged for transporting the machine and/or for producing said rotation or turning of said at least first.

4. Agricultural machine according to any of Claims 1-3, characterized in that support wheels (27, 160, 170, 180) are arranged for adjustment of the working depth for said tools/working means.

5. Agricultural machine according to Claim 4, characterized in that said wheel is rotatable to predetermined positions along an essentially vertical shaft which is coupled to the essentially horizontal shaft of the support wheel, whereby means are aπanged for rotation of said vertical shaft to predetermined positions depending on the adjustment of the units.

6. Agricultural machine according to any of Claims 1-5, characterized in that at least the mutual angle between the first and second aggregates (14 resp. 15) is so adjustable that, at each opportunity when e.g. the direction of travel is changed, the direction of the tools/working means of at least one of the units can be changed, preferably during operation, for the purpose of achieving an adjusted and even working of the ground.

7. Agricultural machine according to any of Claims 1-6, characterized in that it comprises a device for angular adjustment of said rear unit in relation to the angular position ofthe draw rod (10) in the horizontal plane in order to compensate for oblique drawing of the machine during driving.

8. Agricultural machine according to Claim 7, characterized in that the device for compensating for oblique drawing is a lever mechanism ( 1 la, 1 lb, 1 lc, 1 Id), which is activated during rotation of the draw bar (10).

9. Agricultural machine according to Claim 7, characterized in that the device for compensating for oblique drawing comprises two piston and cylinder units (31,32), which are arranged between the roller element (16) and each side ofthe frame (6) and which are mutually activated in order to turn the roller element in relation to the angle of rotation of the draw bar (10) in the horizontal plane.

10. Agricultural machine according to any of Claims 1-9, characterized in that the first unit (14) is so joined with the second unit (15) that, when the first unit is 3

20 rotated or turned to the opposite (essentially minor-inverted) position, both units can take up their predetermined mutual angular positions.

11. Agricultural machine according to any of Claims 1-10, characterized in that the two units (14 resp. 15) are pivotably joined with each other at one of their ends, that, in order to allow rotation of the first unit to the second position, the second unit is joined with the first unit or with the draw bar at a predetermined position from said one end in a flexible way, preferably by means of an extensible, retractile line (22), in each position lockable, and that the two units are joined with each other by means of a parallel link system consisting of two articulated link arms placed above each other and an extending and retracting means, preferably a half- and cylinder unit, extending diagonally between the link arms.

12. Agricultural machine according to any of Claims 1-11, characterized in that the two units (14 resp. 15) are so joined with each other that one end ofthe first unit is movable from one end ofthe the second unit to the other, and vice versa, and that, in order to allow pivoting ofthe first unit to the second position, the second unit is joined with the first unit or with the draw bar (4) in a predetermined position from said one end in a flexible way, preferably by means of an extensible/retractile line (22), lockable in each position.

13. Agricultural machine according to any of Claims 1-12, characterized in that one unit (14) is, preferably via a guidable turntable, pivotably arranged on a draw bar (4) and that the other unit (15) is arranged on the extension of the draw bar, such as by means of an extensible/retractile line (22), lockable in each position, whereby either the draw bar or the front unit is arranged to allow rotation ofthe front unit.

14. Agricultural machine according to any of Claims 1-13, characterized in that the front unit (14) is divided into tools arranged on each side of the draw bar (22) and fixed to extending beams arranged on the draw bar, which are arranged to be pivoted to different predeteιτnined angular positions.

15. Agricultural machine according to any of Claims 1-14, characterized in that the front unit has a draw bar pivotably arranged to predetermined angular positions, and that the rear unit consists of at least one working element at the front frame beam pivotably aπanged to predetermined angular positions, and that the turning of the units takes place by said at least one working element being brought into alignment against the front frame beam and by the draw bar being moved to a position where the connecting end is essentially in alignment with the front frame beam and that thereafter the whole machine is rotated along said at least one working element so that the draw bar with the front unit is moved over to the other side ofthe front frame beam, seen from the plane ofthe ground.

16. Agricultural machine according to any of Claims 1-15, characterized in that it comprises at least one pre-tool (49) with working means, such as cultivator pins or the like, comprising two essentially horizontal, extending perpendicularly out from the draw bar, articulated at the draw bar, preferably upwardly pivotable arms, onto which working means are mounted, preferably at the same mutual distance from each other.

17. Agricultural machine according to any of Claims 1-16, characterized in that it comprises a control unit which can be coupled to a guiding device, such as a GPS- receiver with a memorised earth-type map or the like, for the field in question, or an aπangement for storing of the earth-type map for the field in question or the like, for automatic or manual guiding of the cutting angle and/or working depth for the subsequent tools/working means in order to optimize for the earth-type alternatively weed-type in question.