ADJUSTMENT DEVICE FOR AN AGRICULTURAL MACHINE

Abstract: The invention relates to an adjusting device for an agricultural machine, comprising at least one tool (3, 20) for working the soil, and at least one power member (12) for adjusting the tool (3, 20) in relation to the soil (6). A sensor (16) interacting with the tool (3, 20) detects soil (7, 22) displaced by the tool (3, 20), and a control unit (15) coupled to the sensor (16) controls the power member (12) in accordance with information received from the sensor (16).

Description: Adjustment device for an agricultural machine The present invention relates to an adjustment device for an agricultural machine, comprising at least one tool for working the soil and at least one power unit for adjusting the tool in relation to the soil. Agricultural machines, such as drilling machines, comprise a plurality of tools which work and prepare the soil before material such as seed or fertilizer is to be placed in the soil. Such tools include spring boards and harrow S-tines which can be arranged in a plurality of parallel rows on the agricultural machine. Such tools must function satisfactorily under all soil conditions to ensure that the seeds which are sown will be able to grow and develop to yield a satisfactory crop. The spring board, which is also referred to as clod crusher or crossboard, levels out the soil and crushes clods of earth before the soil is harrowed or worked in some other way. The spring board comprises a plurality of resilient rod elements which are arranged in a line and can be connected to one another by means of a stabilizing bar. The spring board is arranged at an an- gle to the soil so that it slopes forwards in the direction of travel, which means that a bank of earth is built up in front of the clod crusher. The size of the bank of earth depends inter alia on the angle of the spring board to the soil and on the speed of the agricultural machine. The nature of the earth also affects the size of the bank of earth. The size of the bank of earth gives an indication of how the spring board is working the soil. If the bank of earth is too small, the soil is not being worked sufficiently and the soil is not levelled out sufficiently. If the bank of earth is too large, the soil is being worked too much, causing increased fuel consumption of the vehicle pulling the agricultural machine because this increases the power that has to be ex- erted by the pulling vehicle. To achieve the desired working of the soil, the angle of the spring board in relation to the soil can be adjusted manually from the driver's cab of the pulling vehicle. The harrow S-tines are made up of a resilient rod element which is provided with a point at the end directed towards the soil. The harrow S-tines break up the earth before seed and fertilizer are placed in the soil. The depth to which the harrow S-tines are to be introduced into the soil in order to achieve satisfactory working of the soil depends on the properties of said soil. When the harrow S-tines are driven in the soil, a wash forms behind each harrow S- tine. The size of this wash gives an indication of how the harrow S-tines are working the soil. If the wash is too small, the soil is not being worked sufficiently, and, if the wash is too great, the soil is being worked too much, which means increased fuel consumption in the vehicle pulling the agricul- tural machine. In order to obtain a desired working of the soil, the depth of the harrow S-tines in the soil can be adjusted manually from the driver's cab of the pulling vehicle. However, it has been found to be difficult to set the correct angle of the spring board and the correct depth of the harrow S-tines in order to obtain satisfactory working of the soil. The driver who is manoeuvring the agricultural machine is occupied with driving the pulling vehicle and with monitoring a number of functions of the agricultural machine and the pulling vehicle. In addition, the drive speed has increased in recent years, which Hs caused difficulties for the driver to turn around to check how the spring board and the harrow S-tines are working the soil. It is an object of the present invention to solve the above mentioned problems in order thereby to achieve a satisfactory working of the soil. A further object of the invention is to make it easier to manoeuvre the agricultural machine. This is achieved by means of an adjusting device for an agricultural machine of the initrally mentioned kind, comprising a sensor which interacts with the tool and which detects the soil displaced by the tool, and a control unit asso- ciated with the sensor and which controls the power unit in response to information received from the sensor. By means of such an adjustment device, the driver manoeuvring the agricultural machine does not have to check the way the spring board and har- row S-tines are working the soil, but instead he can concentrate on driving the pulling vehicle. The adjustment device ensures that the soil is satisfactorily worked and prepared before seed and fertilizer are placed in the soil, there by fact increasing the possibilities of the sown seed to grow and develop into a crop with satisfactory properties. The invention will in the following be described in greater detail on the basis of embodiments shown in the attached drawings, where Fig. 1 illustrates a first embodiment of the invention, Fig. 2 illustrates a second embodiment of the invention, Fig. 3 illustrates a third embodiment of the invention, Fig. 4 illustrates the third embodiment of the invention in perspective, Fig. 5 illustrates a fourth embodiment of the invention, Fig. 6 illustrates a fifth embodiment of the invention, and Fig. 7 illustrates a wiring diagram for controlling the adjusting device according to the invention. Fig. 1 shows a first embodiment of an adjustment device 1 for an agricultural machine 2 according to the present invention. The agricultural machine 2, which is only shown schematically, comprises an tool in the form of a spring board 3. The spring board 3 is made up of a plurality of resilient rod elements 4 which are arranged in line and are connected to one another by means of a stabilizing bar 5. The spring board 3 is arranged at an angle in relation to the soil 6, so that it slopes forwards in the direction of travel, which means that a bank of earth 7 builds up in front of the spring board 3 when the agricultural machine 2 is driven forwards by a pulling vehicle 8. The pulling vehicle 8 is shown schematically in Fig. 1. As was mentioned in the introductory part of the description, the size of the bank of earth 7 depends on the angle α of the spring board 3 in relation to the soil 6 and on the speed of the agricultural machine 2. The size of the bank of earth 7 gives an indication to how the spring board 3 is working the soil 6. If the bank of earth 7 is too small, the soil 6 is not being worked sufficiently, and, if the bank of earth 7 is too large, the soil 6 is being worked too much, which causes increased fuel consumption in the vehicle 8 pulling the agricultural machine 2, since increased tractive power is required. To achieve a satisfactory working of the soil 6, the angle α of the spring board 3 in relation to the soil 6 can be adjusted by means of the adjustment device 1 according to the present invention. The rod element 4 of the spring board 3 is connected to an axle 10 which can pivot on the frame 9 of the agricultural machine 2 and which is connected by means of an arm 11 to a power member in the form of a hydraulic cylinder 12. The hydraulic cylinder 12 is connected to the frame 9 of the agricultural machine 2. By pivoting the axle 10 by means of the hydraulic cylinder 12, the angle α of the spring board 3 in relation to the soil 6 is changed. If the axle 10 is pivoted clockwise, as is shown in Fig. 1, the angle α between the spring board 3 and the soil 6 is reduced, which causes that the force with which the spring board 3 bears against the soil 6 reduces, which in turn causes the spring board 3 to work the soil 6 less, and the bank of earth 7 in front of the spring board 3 will thus become smaller. If the axle 10 is turned counter-clockwise, the condition will be the opposite. The hydraulic cylinder 12 is acted upon by a pressure force 13. A valve 14 arranged between the pressure source 13 and the hydraulic cylinder 12 adjusts the hydraulic flow to the cylinder 12. The valve 14 and thus the hydraulic cylinder 12 are controlled by a control unit 15 receiving information from a sensor 16 and from a control panel 17 arranged in the pulling vehicle 8. The sensor 16, shown in the embodiment of Fig. 1 is a non-tactile sensor 16, which is connected to the frame 9 of the agricultural machine 2 and is directed towards the lower portion of the spring board 3 where a bank of earth 7 is formed when the agricultural machine 2 is drawn by the pulling vehicle 8. Since the size of the bank of earth 7 provides an indication of how satisfactorily the spring board 3 is working the soil 6, the sensor 16 detects the size of the bank of earth and sends signals concerning this to the control unit 15 which, in response to this information, sends signals to the valve 14 in order to activate the cylinder 12, which thus changes the angle α of the spring board 3 in relation to the soil 6 by pivoting the axle 10. The sensor 16 can consist of an ultrasonic sensor which detects the distance between the bank of earth 7 and the sensor 16. The shorter the distance be- tween the sensor 16 and the bank of earth 7, the larger the bank of earth 7. The sensor is thus placed on the frame 9 of the agricultural machine 2 in front of the spring board 3. By inputting a parameter via the control panel 17, which parameter corresponds to a desired value of the size of the bank of earth 7, the control unit 15 will send signals to the valve 14 so that the cylin- der 12 adjusts the angle α of the spring board 3 and thus the size of the bank of earth 7, such that the size of the bank of earth 7 comes closer to and finally corresponds to the desired value. Fig. 2 shows a second embodiment of the invention in which the sensor 16 comprises a detecting element 18 which is designed to bear against the soil 6 displaced by the tool 3. The detecting element 18 can consist of a tine or a flap which can pivot about an angle sensor 19. The more the detecting element 18 shown in Fig. 2 is pivoted clockwise, the larger the bank of earth 7. The sensor 16 and the hydraulic cylinder 12 are intended to be coupled to a control unit 15 and valve 14, respectively, as is shown in Fig. 1. Fig. 3 shows a third embodiment of the invention in which the sensor 16 with the detecting element 18 is arranged on the pivotable axle 10. The sensor 16 extends between two rod elements 4 so that the detecting element 18 can come into conduct with the bank of earth 7. The advantage of arranging the sensor 16 directly on the pivotable axle 10 is that the sensor 16 turns together with the axle 10 when the latter is pivoted and when the angle α of the spring board 3 in relation to the soil is changed. Fig. 4 shows the fourth embodiment in perspective. It can clearly be seen how the sensor 16 extends between two rod elements 4. To achieve satisfactory monitoring of the size of the bank of earth 7, it is conceivable to arrange a plurality of sensors 16 along the spring board 3. The signals which are sent from the sensors 16 can be processed in the control unit 15, and an image of the appearance of the bank of earth 7 along the spring board 3 can be obtained. It is also possible for the spring board 3 to be divided up along its length into a plurality of sections which can be pivoted independently of one another about axles 10. Fig. 5 shows a fourth embodiment of the present invention. What distinguishes this embodiment from the one shown in Fig. 1 is that the tool comprises of harrow S-tines 20. The harrow S-tines 20 comprise a resilient rod element 4 which is provided with a point 21 at the end directed towards the soil 6. As was mentioned in the introductory part of the description, the har- row S-tines 20 break up the soil 6 before seed and fertilizer are placed in the soil 6. The depth to which the harrow S-tines 20 are to be introduced into the soil 6 to achieve satisfactory working of the soil depends on the character of the soil 6 and on the speed of the agricultural machine 2. To achieve a desired working of the soil 6, the depth of the harrow S-tines 20 in the soil can be adjusted by a hydraulic cylinder 12 in the same way as is described in connection with the first embodiment. When the harrow S-tines 20 are driven in the soil 6, a wash 22 is formed behind each harrow tooth 20. The size of the wash 22 provides an indication to how the harrow S-tines 20 are working the soil 6. A sensor 16 is arranged behind one or more of the harrow S-tines 20 and is directed towards the wash 22 formed behind the harrow tooth 20. The sensor 16 can comprise an ultrasonic sensor for non-tactical detection. The sensor 16 and the hydraulic cylinder 12 are intended to be coupled to a control unit 15 and valve 14, re- spectively, as is shown in connection with the first embodiment. If the wash 22 is too small, the soil 6 is not being worked sufficiently, and, if the wash 22 is too great, the soil 6 is being worked too much, which causes increased fuel consumption in the vehicle 8 pulling the agricultural machine 2, since greater power is required to pull the harrow S-tines 20. By inputting a pa- rameter via the control panel 17, which parameter corresponds to a desired value of the size of the wash 22, the control unit 15 will send signals to the valve 14 so that the cylinder 12 adjusts the depth of the harrow S-tines 20 in the soil 6 and thus the size of the wash 22, such that the size of the wash 22 comes closer to and finally corresponds to the desired value. Fig. 6 shows a fifth embodiment of the invention in which two rows of tools 20 and been coupled together by means of a linking bar 23. The axle 10 of the rear row comprises an arm 11 connected to a hydraulic cylinder 12. When the cylinder 12 pivots the rear axle 10, the pivoting movement is transmitted to the front axle 10 via the linking bar 23. A sensor 16 is arranged to detect the soil 6 displaced by the tool 20, as has been described in connection with the embodiments above. In the embodiment shown in Fig. 4, the tool comprises of harrow S-tines 20, but the tool can alternatively comprise of spring boards 3. The sensor 16 comprises a non-tactile sensor 16 in the embodiment shown, but it is also possible for the sensor 16 to comprise a detecting element 18 which is arranged to bear against the soil 6 displaced by the tool, as is described in connection with the illustrative embodiment shown in Fig. 2. Fig. 7 shows a wiring diagram 24 for controlling the adjustment device 1 according to the invention. The wiring diagram 24 shows two working members in the form of hydraulic cylinders 12 are intended to be coupled to the tools 3, 20 of the agricultural machine 2. The valve 14 comprises of two two-way valves 25, 26 which are controlled electrically. By actuating the first two-way valve 25, each piston rod 27 in the cylinders 12 is displaced out of the respective cylinder 12. When the second two-way valve 26 is actuated, each piston rod 27 is displaced inwards into the cylinders 12. Arranged between the pressure source 13 and the first two-way valve 25 there is a variable throttle valve 28, so that the speed of flow of the hydraulic fluid to the cylinders 12 can be varied. By increasing the through-flow area of the throttle valve 28, the tool 3, 20 can be adjusted more quickly if the size of the bank of earth 7 or wash 22 is outside a predetermined interval and, in the same way, the tools 3, 20 can be adjusted more slowly if the through-flow area is reduced when the size of the bank of earth 7 or wash 22 is within a predetermined interval. Alternatively, this adjustment can be achieved by allowing the flow which controls the two-way valves 25, 26 to pulsate. Another possible way of achieving this adjustment is to use so-called proportional valves (not shown). Under certain circumstances, such as when working earth of a particular nature or when servicing the agricultural ma- chine 2, it may be desirable to uncouple the action of the adjustment device on the tools 3, 20 so that these can be adjusted manually. The tools 3, 20 may be adjusted individually, which means that each tool 3, 20 is provided with a power member 2 and a sensor 16, so that the position of the tool 3, 20 in relation to the soil can be adjusted independently of the position of other tools 3, 20 in relation to the soil. Each element is here to be understood as a group of interconnected tools 3, 20 or individual tools 3, 20.

Claims: Claims 1. Adjustment device for an agricultural machine, comprising at least one tool (3, 20) for working the soil, and at least one power unit (12) for adjusting the tool (3, 20) in relation to the soil (6), characterized by a sensor (16) which interacts with the tool (3, 20) and detects soil (7, 22) displaced by the tool (3, 20), and a control unit (15) which is associated with the sensor (16) and which controls the power unit ( 12) in response to information received from the sensor (16). 2. Device according to Claim 1, characterized in that the sensor (16) is a non-tactile sensor, such as an ultrasonic sensor. 3. Device according to Claim 1, characterized in that the sensor (16) comprises a detecting element (18) which is placed in such a way that the soil (7) displaced by the tool (3) is allowed to contact the detecting element. 4. Device according to any of the preceding claims, characterized in that a plurality of tools (3, 20) are arranged in a row. 5. Device according to Claim 4, characterized in that at least two substantially parallel rows of tools (3, 20) are arranged on the agri- cultural machine (2). 6. Device according to any of the preceding claims, characterized in that the tool is designed as a spring board (3). 7. Device according to any of Claims 1-2 and 4-5, characterized in that the tools are designed as harrow S-tines (20). 8. Device according to any of the preceding claims, characterized in that the power unit comprises of a hydraulic cylinder (12). 9. Device according to any of the preceding claims, characterized in that each tool (3, 20) is individually adjustable.

Inventors: STARK CRISTER, STARK, CRISTER
Applicants: STARK CRISTER, VAEDERSTAD VERKEN AB, STARK, CRISTER, VAEDERSTAD-VERKEN AB
Application year: 2001
Main classification: A01B63
IPC codes: A01B63