AGRICULTURAL APPARATUS

Agricultural apparatus

The present invention relates to an agricultural machine comprising at least two working members, such as sowing, ploughing or harrowing bodies, which are arranged rotatably on a chassis part. The invention also relates to a working member for such an agricultural machine.

Agricultural machines, primarily machines for soil cultivation and sowing machines of various types, have for a long time had different forms of sprung working members. This applies to machines with both different forms of tines and different forms of discs, so-called disc shares.

The sprung mounting normally serves to give way when a stationary obstacle is run into and to improve ground adaptability, that is to say bring about automatic compensation when the working depth decreases or increases.

The sprung mounting is also intended to ensure that the working member vibrates during driving. The vibration contributes to earth, straw and plant remains being shaken off the working member. In many cases, the vibration is also desirable in order that the working member breaks up the earth better.

Great efforts have been made to find systems which achieve good ground adaptability and thus a precise working depth. This problem has been solved by dividing the frame into smaller sections and by providing each section with support members. Another known solution is to provide each sprung working member with support wheels. However, it has proved to be impossible to provide each sprung working member with support wheels and at the same time make all the working members work with the same force. If, moreover, a frame bearing a load of fertilizer or seed for sowing is arranged on the agricultural machine, a machine is obtained in which the frame height above the ground varies depending on how heavily loaded the machine is. This is a great inconvenience as the frame often bears other working members which have different conditions of action in the ground. The rebound of the working member is also affected by the driving speed as the earth resistance increases at increased driving speed.

Swedish patent SE-C-181 360 discloses an agricultural implement which comprises a number of share arms which are each mounted rotatably on a shaft on a frame. The share arms are interconnected in pairs by means of rods or links and to a swingle-tree. When one share arm collides with a stone, it is pivoted backwards, the other share arm then being pivoted forwards by means of the rods and the swingle-tree. This arrangement means that the risk is low that both share arms will simultaneously collide with an 5 obstacle in the ground.

German patent DE-C-587 804 relates to an agricultural implement which comprises a number of share arms which are joined together by means of a rope. The rope runs via blocks arranged on each share arm and a block o arranged on a lever. The lever is articulated on the one hand in a frame for the agricultural implement and on the other hand to a towing arrangement for the implement. When, for example, a tractor tows the agricultural implement, the lever 9 will tension the rope, so that the share arms will adopt an end position against a stop. If a share arm collides with a stone in 5 the ground, the share arm is rotated backwards in the direction away from the tractor- The lever will then also be rotated backwards in order to relieve the load on the rope. The other share arms are not affected.

The object of the present invention is to produce an agricultural machine of o the type indicated in the introduction, the working members of which absorb an essentially equal force against the ground.

Another object is to produce an agricultural machine, the working members of which essentially follow the shape of the ground. 5

A further object is to produce an agricultural machine, the position of which above the ground is independent of its weight.

Yet another object is to produce an agricultural machine, the working o members of which are not affected by the speed of the machine.

This is achieved by the present invention by virtue of the fact that said working members are interconnected by means of elongate connecting parts which transmit movement and distribute force from one of said working 5 members to another of said working members, so that when one of said working members moves from an initial position in one direction under the action of a force, another of said working members moves in another direction under the action of this force. By virtue of the fact that the working members are connected by elongate connecting parts, such as a rope, the average setting of the working members remains unchanged under different load conditions, which affords the possibility of loading the machine with, for example, different types and sizes of seed containers without the height of the chassis part above the ground being changed. As a consequence of this, the agricultural machine offers a high degree of ground adaptability, which means that the working depth in the ground can be kept at an essentially constant level for all the working members irrespective of the type of ground or the driving speed.

The invention is described in greater detail below with reference to exemplaiy embodiments shown in the appended figures, in which

Fig. 1 is a perspective view of an agricultural machine according to a first exemplaiy embodiment of the present invention, which is provided with a seed container and is towed by a tractor,

Fig. 2 is a perspective view of the agricultural machine according to the first exemplaiy embodiment, in which the components of the machine are shown in greater detail, Fig. 3 is a side view of the agricultural machine according to the fnst exemplaiy embodiment,

Fig. 4 is a side view of an agricultural machine according to a second exemplary embodiment,

Fig. 5 is a side view of an agricultural machine according to a third exemplary embodiment,

Fig. 6 is a side view of an agricultural machine according to a fourth exemplary embodiment,

Fig. 7 is a side view of an agricultural machine according to a fifth exemplaiy embodiment, Fig. 8 is a top view of the agricultural machine according to the fifth exemplary embodiment,

Fig. 9 is a detailed view from above of the agricultural machine according to the fifth exemplary embodiment,

Fig. 10 is a perspective view of an agricultural machine according to a sixth exemplary embodiment,

Figs 11 and 12 are detailed views of the agricultural machine according to the sixth exemplary embodiment,

Fig. 13 is a side view of an agricultural machine according to a seventh exemplaiy embodiment, Fig. 14 is a perspective view of an agricultural machine according to an eighth exemplary embodiment,

Figs 15 and 16 are detailed views of the agricultural machine according to the eighth exemplary embodiment, Fig. 17 is a side view of an agricultural machine according to a ninth exemplaiy embodiment, and

Fig. 18 is a top view of an agricultural machine according to the ninth exemplaiy embodiment.

Fig. 1 shows an agricultural machine 1 according to a first exemplary embodiment. The machine 1 comprises a chassis part 2 which forms a frame 2 for the components included in the machine. Fig. 1 indicates that a seed container 4 is arranged on the frame 2. The agricultural machine 1 is coupled to a tractor 6 in a conventional manner, which means that the tractor 6 tows the machine 1 over the ground.

A number of working members in the form of disc shaies 8, 9 are arranged side by side and interconnected by means of an elongate connecting part in the form of a rope 10, which will be described in greater detail below. As shown in Fig. 1, two rows of disc shaies 8, 9 are arranged parallel to one another. Arranged parallel to the two rows of disc shares 8, 9 is a row of support wheels 11.

Fig. 2 shows the agricultural machine 1 according to the first exemplary embodiment in greater detail. The first row of disc shares 8 is arranged on a first shaft 12 connected to the frame 2. The second row of disc shares 9 is arranged on a second shaft 13 connected to the frame 2. Each disc share 8, 9 is mounted on a leg 14, 15 which is arranged rotatably on the respective shaft 12, 13 by means of a split sleeve 16, 17. Arranged on the leg 14, 15 and the sleeve 16, 17 is an arm 18, 19 which extends in a direction essentially away from the disc share 8 and the leg 14. In the exemplary embodiment shown in Fig. 2, the first and second shafts 12, 13 have an essentially square cross section. The split sleeve 16, 17 also has an essentially square cross section. The split sleeve 16, 17 is displaced in the circumferential direction in such a manner that four interspaces are formed, in which springing members 20 in the form of rod-shaped rubber elements are arranged. The rubber rods contribute to the disc shares striving to adopt an initial position. In the exemplary embodiment shown, the number of disc shares 8 on the fust shaft 12 is the same as the number of disc shares 9 on the second shaft 13 and also the same as the number of support wheels 11. The support wheels 11 are arranged on a third shaft 21 which extends essentially parallel to the first and second shaft 12, 13. Seen in the direction of travel, indicated by an arrow P in Fig. 2, of the machine 1, each disc share 8, 9 and support wheel 11 is located on a line. The disc shares 8, 9 and support wheels 11 that are located on the same line in the direction of travel are interconnected in an articulated manner by means of first and second link stays 22, 23. The 0 first link stay 22 connects the arms 18, 19 on the two disc shares 8, 9 aπanged around the first and second shaft 12, 13. The second link stay 23 connects the arm 19 of the disc share 9 arranged on the second shaft 13 and an arm 24 arranged on the support wheel 11. It is possible for the support wheels 11 to be arranged with a bogie. 5

At the free end of each arm 18 of the disc shares 8 arranged around the first shaft 12, a block 26 is arranged, which comprises a bearing-mounted pulley 28, the periphery of which has a circumferential groove 30. The blocks 26 aπanged on the arms 18 together form a first set of blocks 26 which are o intended to interact with a second set of blocks 32 arranged on the frame 2, which have a bearing-mounted pulley 34 with a circumferential groove 36, via the rope 10 which runs via each block 26, 32 in the peripheral groove 30, 36 arranged in the respective pulley 28, 34. The ends of the rope 10 are connected firmly to the frame 2. 5

If the agricultural machine 1 happens to pass over, for example, a rise in the ground, the disc share(s) 8, 9 making contact with the rise is (are) pushed upwards. This means that the distance between the blocks 26 arranged on the arm 18 of the disc shares 8 that are acted on by the rise and the second o set of blocks 32 aπanged on the frame 2 will increase. On account of the fact that the rope 10 is tensioned firmly in the frame 2 and that the rope 10 is essentially inelastic, the distance between the blocks 26 arranged on the arm 18 of the disc shares 8 that are not affected by the rise and the second set of blocks 32 aιτanged on the frame 2 will decrease. This results in the disc 5 shares 8, 9 that are not affected by the rise being pulled in the direction towards the ground by the rope 10. As the disc shaies 8, 9 on the first and second shaft 12, 13 and also the support wheels 11 are connected by means of the first and second link stays 22, 23, the corresponding disc share 9 on the second shaft 13 and the coπesponding support wheel 11 will also follow the movement of the disc share 8 on the first shaft 12.

In order to increase the stability of the agricultural machine 1 in the lateral direction, the rope 10 can be divided approximately half way along the length of the rope 10, so that the disc shares 8, 9 on one side of the agricultural machine 1 interact via one part of the divided rope 10 and the disc shares 8, 9 on the other side of the agricultural machine 1 interact via the other part of the divided rope 10. The ends of the rope 10 are connected on the one hand to the frame 2 at the sides of the agricultural machine 1 and on the other hand to a central region of the frame 2, which is shown in Fig. 2.

An adjustable force member, in the form of a hydraulic cylinder 25 or a spring, can be arranged on the rope 10. By means of a hydraulic cylinder 25, the force in the rope 10 can be regulated and also a vibration can be generated in the rope 10. Vibrations are then generated in the disc shares 8, 9, which shakes off earth, straw and other plant remains which have stuck to the disc shares 8, 9. 0

Fig. 3 shows a side view of the agricultural machine 1 according to the first exemplaiy embodiment. A tractor 6 is arranged so as to tow the agricultural machine 1 on the ground. The disc shares 8, 9 aπanged around the first and second shafts 12, 13 are located at a given depth below the surface of the 5 ground, which depth can be adjusted by interaction between the support wheels 11 and the towing coupling of the tractor. The arrangement for this adjustment is previously known per se and is therefore not shown in Fig. 3.

Fig. 4 shows a side view of an agricultural machine 1' according to a second o exemplary embodiment. This embodiment is very reminiscent of the first embodiment but differs in that the first set of blocks 26 are arranged on the arms 19 instead of on the arms 18 and also in that the second set of blocks 32 are arranged on the frame 2' at a fastening point located in the rear region of the agricultural machine 1'. 5

Fig. 5 shows a side view of an agricultural machine 1" according to a third exemplaiy embodiment. This embodiment is also veiy reminiscent of the first embodiment but differs in that the first set of blocks 26 are arranged on a projection on a leg 38 of the support wheel 11 instead of on the arms 18 and also in that the second set of blocks 32 are arranged on the frame 2" at a fastening point located in the rear region of the agricultural machine 1".

Fig. 6 shows a side view of an agricultural machine 1'" according to a fourth exemplaiy embodiment. According to this embodiment, the first and second link stays 22, 23 connect the legs 14, 15 of the disc shares 8, 9 and the leg 38 of the support wheel 11. A link arm 40 is arranged on the leg 15 of the disc share 9 arranged rotatably around the second shaft 13. The second set of blocks 32 are arranged on an arm 19'" of the respective disc share 9 arranged on the second shaft 13. The arm 19'" preferably extends in a direction which essentially coincides with the direction of extension of the respective leg 15. With the link stays 22, 23, the link arm 40 and the blocks 26, 32 connected together according to this embodiment, the disc shares 8, 9 and the support wheels 11 that are located on the same line in the direction of travel are permitted to move relative to one another.

Fig. 7 shows a side view of an agricultural machine 1^IV according to a fifth exemplaiy embodiment. In this case, the working members consist of sowing tines 42 arranged side by side on a number of parallel shafts 44, 45, 46, 47. Another name for a sowing tine 42 is a cultivator tine. According to the exemplary embodiment shown, four parallel shafts 44-47 are arranged in a row one following another. The agricultural machine 1^IV is intended to be towed by, for example, a tractor (not shown in Fig. 5) in the direction of the aιτow P. As in the preceding exemplaiy embodiments, the sowing tines 42 are rotatable around the shafts 44-47. Rubber dampers are preferably also aπanged between a split sleeve aιτanged around the shaft 44-47 and the shaft, as described in connection with Fig. 2.

An arm 48, 49 is arranged on each sowing tine 42. Each arm 48, 49 comprises a guide element for a rope 10, in the form of a bearing-mounted pulley 50, the periphery of which has a circumferential groove 52. The arm 48 on each sowing tine 42 mounted rotatably on a first shaft 44 at the very front in the direction of travel of the agricultural machine 1^IV is arranged above the shaft 44, seen from the side of the agricultural machine 1^IV in Fig. 7. The arm 49 on each sowing tine 42 mounted rotatably on a second shaft 45 seen in the direction of travel of the agricultural machine 1^IV is aπanged below the shaft 45, seen from the side of the agricultural machine 1^IV in Fig. 7. A rope 10 runs via the pulleys 50 arranged on the arms 48, 49, which rope 10 transmits movement and distributes force between the sowing tines 42 arranged on the shafts 44-47. If, for example, one of the sowing tines 42 on the first shaft 44 passes over a rise in the ground, this sowing tine 42 will move upwards, that is to say in the counterclockwise direction in Fig. 7. The pulley 50 bearing-mounted on the arm 48, 49 will then tension the rope 10, so that the other sowing tines 42 arranged on the first and second shaft 44, 45 will be rotated in the clockwise direction around the first and second shaft 44, 45. The sowing tines 42 on the third and fourth shafts 46, 47 interact in the same way as described for the sowing tines 42 on the first and second shafts 44, 45.

In order further to improve the ground adaptability and to close the furrow formed in the ground by the respective sowing tine 42, a support wheel 54 can be arranged on each sowing tine 42. The dotted lines in Fig. 7 show the sowing tines 42 and the support wheels 54 in an angled-up position, which can result if a rise in the ground is passed over, as described above. The sowing tines 42 are provided with a share 51. For sowing, the share 51 can be designed in such a manner, for example asymmetrically with a projection 37, that an earth bank B is produced on one side of the furrow F formed by the share 51 on the sowing tine 42. The support wheel 54 arranged on the respective sowing tine 42 will then interact with the sowing tine 42, so that the earth bank B is levelled and fills in the furrow F again, and so that the support wheel 54 presses down on the filled-in furrow F. This is achieved by virtue of the fact that the axis of rotation of the support wheel 54 is inclined at an oblique angle α in relation to the direction of travel, as is best shown in a top view in Figures 8 and 9. By virtue of the fact that the support wheel 54 rolls at an angle in relation to the direction of travel, the support wheel 54 will automatically clean itself in wet conditions when the earth is sticky. The sowing depth, that is to say the depth at which the share 51 will be set by making the support wheel 54 adjustable along the sowing tine 42. The angle of the support wheel 54 in relation to the direction of travel can be adjustable. The distance of the support wheel 54 from the sowing tine 42 can also be adjustable.

Fig. 8 shows a top view of the agricultural machine 1^IV according to the fifth exemplaiy embodiment. The rope 10 runs zigzag via the pulleys 50 arranged on respective arms in such a manner that the rope 10 is at one end 56 connected to in a frame 2^IV of the agricultural machine 1^IV and runs via the pulley 50 on the arm 49 of the sowing tine 42 arranged on the second shaft 45. The rope 10 then continues to the pulley 50 arranged on the arm 48 of the sowing tine 42 arranged on the first shaft 44, and then on to the pulley 50 of an arm 49 of a sowing tine 42 arranged next to the first-mentioned sowing tine 42 on the second shaft 45 etc., finally being anchored by its other end 58 in the frame 2^IV. As shown in Fig. 8, the sowing tines 42 on the first and second shaft 44, 45 are not arranged on a line, seen in the direction of travel of the agricultural machine 1^IV.

Fig. 10 shows a perspective view of an agricultural machine 1 according to a sixth exemplaiy embodiment. The agricultural machine l^v comprises a seed container 4^V arranged on a frame 2^V of the agricultural machine l^v. At the rear end of the frame 2^V, two wheels 39^v are arranged. On each side of a central part of the frame 2^V, which supports the seed container 4^V, two manoeuvrable frame parts 2^V are arranged, which are very reminiscent of the agricultural machine 1^IV according to the fifth embodiment but differ in that each working member in the form of sowing tines 42^v is provided with a parallel guide from the frame 2^V, which will be described in greater detail with the aid of Figures 11 and 12. 0

In sowing, the requirement for accuracy is great, the objective being to plant the seed at a depth measured from the surface of the ground of approximately 1-5 cm depending on the type of crops. The variation in depth between different seeds that are planted during the same sowing is to be 5 minimal; less than 0.5 cm is desirable. As the surface of the ground is often uneven and the agricultural machine l^v works over a great width, each individual sowing tine 42 must be compensated for unevennesses in the surface of the ground if a constant sowing depth is to be obtained.

o Figures 11 and 12 shows detailed views of the sowing tines 42^v according to the sixth exemplaiy embodiment shown in Fig. 10. The sowing tine 42 ^v, which has a leg 14 , is arranged rotatably around a shaft 44 ^v by means of a split sleeve 16^v which accommodates damping members 20^v in the form of rubber rods, as described in the exemplary embodiment according to Fig. 2. 5 An arm 48^v, which at an outer end has a bearing-mounted pulley 50^v for a rope 10, is also arranged on the split sleeve 16^v. At that end of the sowing tine 42^v which faces away from the sleeve 16^v, a cultivating member in the form of a share 51 is connected in an articulated manner on the sowing tine 42 . The share 51 can be of, for example, the goose-foot type, which share 51 strives to travel at the coπect angle and thus requires minimum towing force. Also arranged on the share 51 is a sowing tube 53, on which a support wheel 54^v is adjustably arranged. At that end of the sowing tube 53 which faces away from the surface of the ground, a first end 55 of a parallel stay 57 is connected in an articulated manner. A second end 59 of the parallel stay 57 is connected in an articulated manner to a lever 61 connected firmly to the shaft 44^v around which the split sleeve 16^v is arranged.

Fig. 11 shows the agricultural machine l^v in a normal position above the surface of the ground. If a rise in the surface of the ground is encountered, the sowing tine 42 will rotate in the counterclockwise direction around the shaft 44^v. As the lever 61 is connected firmly to the shaft 44 ^v, the lever 61 will not be rotated around the shaft 44 ^v, which means that the parallel stay 57 will transmit a movement to the sowing tube 53 which in turn moves at an angle and adjusts the share 51 in relation to the sowing tine 42 in order that the sowing depth is maintained.

In order to set the desired sowing depth d for the respective sowing tine 42 ^v, the parallel stay 57 can, for example, be length-adjustable (not shown) or the support wheel 54 can be moved along the sowing tube.

Fig. 13 shows, according to a seventh exemplaiy embodiment, how the agricultural machine 1^VI can be provided with a height-regulating bearing wheel 63 for the frame 2^VI. According to the exemplary embodiment shown, the bearing wheel 63 is mounted at an articulation 65 by a leg link 67 in the frame 2^VI. Also arranged at said articulation 65 is an arm link 69 which has at one end a guide element in the form of a bearing-mounted pulley for a second rope 73, which second rope 73 is not connected to the first- mentioned rope 10. The second rope 73 runs on via a further wheel guide element in the form of a bearing-mounted pulley 71 mounted in the frame

2^VI. By means of a force member (not shown) arranged between the frame 2^VI and the second rope 73, the leg link 67 of the bearing wheel 63 can be rotated around the articulation 69, which means that the height H of the frame 2 above the surface of the ground can be regulated. This embodiment is suitable where, for example, a seed container 4 is arranged on the agricultural machine 1^VI and the same working depth d of the working members 42 ^VI is desired irrespective of the weight of the agricultural machine 1 When the weight of the agricultural machine 1^V! decreases as a result of the quantity of seed in the seed container 4^V! decreasing, the force acting on the second rope 73 will gradually decrease, so that the bearing wheel 63 will absorb a smaller force, so that the force acting on the working members 42^VI will in this way remain constant.

Fig. 14 shows a perspective view of an agricultural machine l^vπ according to an eighth exemplary embodiment. In this case, the working members consist of a number of ploughing bodies 60 arranged tiltably on a frame 2^vπ. The frame 2^vπ comprises a longitudinal beam 62 which is intended to be arranged behind a towing vehicle such as a tractor (not shown in Fig. 14) so that the agricultural machine l^vπ will be towed in a direction which coincides essentially with the longitudinal direction of the beam 62. Arranged on the longitudinal beam 62 is a number of crossbeams 64 which extend essentially transversely to the direction of extension of the beam 62.

Aπanged at that end 68 of each crossbeam 64 which faces away from the longitudinal beam 62 is a ploughing body 60. The ploughing body 60 comprises a contact element 70 which preferably has two essentially parallel grooves 72. The grooves 72 are intended to interact with two essentially parallel ridges (not shown in Fig. 13) arranged on a support surface 74 at the end 68 of the respective crossbeam 64. The grooves 72 and the ridges thus form mutually complementary members. In a state of equilibrium, the ploughing body 60 extends essentially parallel to a normal to the support surface 74.

A rope 10 extends through each support surface 74 and contact element 70 and runs on via a guide element in the form of a bearing-mounted first circular pulley 76 airanged on each ploughing body 60 and also via a second circular pulley 78 mounted on each crossbeam. The respective ends 56^vπ, 58^vπ of the rope 10 are arranged on a regulatable force member in the form of a hydraulic cylinder 80. Alternatively, the cylinder 80^vπ can be replaced by a spring. By means of the hydraulic cylinder 80^VIi, the force in the rope 10 can be regulated and also a vibration can be generated in the rope 10, which in turn generates vibrations of the ploughing bodies 60 in order to shake off earth, straw and other plant remains which have stuck to the ploughing bodies 60. A stop is arranged on the longitudinal beam 62 in order to limit the stroke length of the hydraulic cylinder 80^vπ and to relieve the load on the hydraulic cylinder 80^VI! in the event of great pulling forces in the rope 10. The rope 10 arranged on the agπcultural machine 1 ^vπ has a stone-releasmg function for the ploughing bodies 60. which is described in greater detail in connection with Figures 15 and 16. Fig. 14 shows a side view of a ploughmg body 60 in an initial position In the event that the ploughing body 60 Ξ collides with a stone or another object that offers resistance, the ploughing body 60 is tilted or folded away from the stone, as shown m Fig 15. the rope 10 then being tensioned When the ploughing body 60 is folded awa\ from the stone, the contact element 70 of the ploughing body 60 is rotated around an imaginary axis and is guided by the ridges 82 on the support c surface 74 of the crossbeam 64 When the ploughmg body 60 has passed the stone, the ploughmg body 60 returns to its initial position, as shown m Fig 15

Figures 17 and 18 show a side viev_* and a top view respectively of an 5 agπcultural machine 1 ^VI1! according to a ninth exemplaiy embodiment. In this case, the agπcultural machine l ^vπ compπses a number of part frames 85 on which a number of working members 86 are arranged. The working members 86 are spring-mounted by means of springing members 84 on shafts 87 of the part frame 85. The working members 86 on each part frame C 85 can be seen as a single working member 86 which is divided into a number of part working members. The part frame 85 is mounted in the frame 2 of the agricultural machine l^vπι by means of a parallelogram 88. The part frame 85 is connected firmly to an upwardly extending link 89. the upper end 90 of which is connected in an articulated manner to one end 91 Ξ of an upper parallel stay 92. The other end 93 of the upper parallel stay 92 is connected in an articulated manner to an upper end 94 of a link 95 connected firmly to the frame 2^VII! of the agricultural machme 1 The lower end 96 of the link 95 is connected in an articulated manner to one end 97 of a lower parallel stay 98. The other end 99 of the lower parallel stay 98 c is connected in an articulated manner to the part frame 85. Also arranged on the part frame 85 is a support wheel 100. The support wheel 100 is articulated on the part frame 85 by means of a fork 101. The position of the fork 101 and thus of the wheel 100 m relation to the part frame 85 is defined by an adjustment arrangement 102. The angle of the fork 101 in relation to 5 the part frame 85 can therefore be fixed by means of the adjustment arrangement 102.

The frame 2^vπι of the agricultural machme l^vπι is provided with a projection 103. Arranged on the projection 103 is a rope pulley 104. A rope 105 is also arranged on the upper parallel stay 92. A rope 10 runs via the rope pulleys 104. 105 arranged on the projection 103 and the upper parallel stay 92. By arranging a number of part frames 85 side by side, as shown in the top view in Fig. 18. the rope 10 can be arranged so that it runs via the rope Ξ pulley 105 of the upper parallel stay 92 of a part frame 85, on to the rope pulley 104 on the projection 103 of the agricultural machine 1 ^' and then on to the rope pulley 105 of the upper parallel stay 92 of the adjacent part frame 85.

i : When a part frame 85. via the wheel 100 and the working members 86 on the part frame 85, is pushed upwards by an unevenness in the ground, such as a rise or a small mound, the rope 10 is tensioned so that the other part frames 85 will be pressed downwards by the rope 10. The wheels 10, however, will ensure that the working members 86 are not pressed down

I Ξ deeper into the ground. By means of the parallel stays 92. 98. the part frames 85 will always be raised or lowered essentially at right angles to the plane in which the part frame 85 extends. For the sake of clanty, the parallelogram 88 has been omitted in the top view in Fig. 18.

2 C According to the exemplar}' embodiments shown above, the elongate connecting parts 10 can comprise a rope, steel wire rope, carbon fibre rope, chain, chain cable or the like.

Instead of a rope 10 or in combination with the rope 10, use can be made of 2 ≡ connecting rods and push rods which interact with a swingle-tree which then replaces the bearing-mounted pulley 28, 50.