CONTROL DEVICE FOR AN AGRICULTURAL COMMERCIAL VEHICLE AND METHOD FOR OPERATING THE COMMERCIAL VEHICLE

Description

[0001] The invention relates to a control device for an agricultural vehicle for controlling the inclination of a distributor linkage. The invention further relates to an agricultural vehicle and a method for operating an agricultural vehicle.

[0002] These agricultural vehicles, also known as field sprayers, are used to apply materials such as fertilizers, pesticides, and / or seeds. To spread the material over a large area of ​​the field, these vehicles are equipped with a spreader boom that can have a working width of up to 40 meters. Spray nozzles are attached to the spreader boom, which spray the material onto the soil. For efficient application, the distance between the spreader boom and the ground should remain as constant as possible across the entire working width.

[0003] Problems arise when the agricultural vehicle travels in ruts of varying depths, unevenly within a furrow, or on a slope of the field being cultivated. Such unevenness can cause the ends of the spreader boom to come into contact with the soil and / or vegetation, resulting in damage. Furthermore, the homogeneous distribution of the applied material is compromised by adverse drift effects caused by the angled position of the spreader boom.

[0004] To compensate for unwanted movements around the vehicle's longitudinal axis, devices are known that have a pendulum suspension and tilt or distance sensors, and which attempt to compensate for this tilt using actuators. Generally, a horizontal position of the distributor linkage relative to the ground being worked is desired.

[0005] From DE 20 2007 011 631 U1, for example, a suspension device for a distributor linkage is known, wherein two fluid level valves are arranged in the area of ​​the suspension of a subframe on the vehicle. Depending on the inclination position of the distributor linkage relative to the vehicle, the valves are opened or closed differently. Specifically, the valves exert pressure on an actuator proportional to the deflection of the distributor linkage, which causes the fluid to flow around the coupled actuator. The actuator, which is expediently designed as a pneumatic and / or hydraulic actuator, is thereby activated.

[0006] Activating the actuator causes the distributor linkage to pivot. The actuator can thus change the angle of the distributor linkage. Once the angle is corrected, the valve closes again.

[0007] However, there are situations, such as road transport or when folding and unfolding the spreader boom, where the spreader boom must be rigidly connected to the agricultural vehicle via the actuator. For this purpose, shut-off valves are installed in the supply lines to the actuator. Once these are closed, no fluid can escape from the actuator, and the spreader boom is rigidly connected to the agricultural vehicle.

[0008] The subsequent opening of the shut-off valves, especially with asymmetrically folded distributor linkages, can lead to uncontrolled and therefore damaging movements of the distributor linkage. Ideally, the shut-off valves should be designed to be seat-tight. This means that no oil can pass through when closed.

[0009] Although DE 10 2016 110 693 A1 discloses a control device for an agricultural vehicle with a double-folding distributor boom for applying materials such as fertilizers, pesticides, or seeds, comprising a control unit and associated pressure control valves for adjusting the tilt of the distributor boom, each pressure control valve is assigned a locking valve to secure the distributor boom. This valve has only two controllable opening states: "closed" and "open." However, to prevent damaging movements of the distributor boom, the pressure control valves must be adjusted to the pressure values ​​simultaneously measured between the locking valves and the actuator each time the locking valves open. This has proven to be very complex from a control engineering perspective.

[0010] In the pre-published EP 3 449 729 A1, a control device for an agricultural vehicle with a double-folding distributor boom for applying material such as fertilizer, pesticides, or seeds is described, comprising a control unit and pressure control valves connected thereto for controlling the tilt of the distributor boom, wherein each pressure control valve is assigned a fully closable proportional valve for locking the distributor boom, and the control unit is assigned a data storage device in which initial setpoint pressure values ​​of the pressure control valves assigned to different folding states of the distributor boom and / or electrical control signals assigned to the initial setpoint pressure values ​​are stored, wherein the pressure control valves and the proportional valves are hydraulic and / or pneumatic valves, and wherein the control device includes an actuator for the distributor boom connected to it.wherein the actuating element comprises at least one pneumatically and / or hydraulically operating cylinder, and wherein the control unit is configured such that the pressure regulating valves are adapted to the associated initial setpoint pressure when the shut-off valves are opened.

[0011] In contrast, the invention is based on the objective of providing a control device for an agricultural vehicle that reduces the risk of uncontrolled movements of the distributor linkage, particularly when opening shut-off valves. The invention is further based on the objective of providing an agricultural vehicle and a method for operating an agricultural vehicle.

[0012] This problem is solved according to the invention by a control device having the features of claim 1. With regard to the agricultural vehicle, the problem is solved by the subject matter of claim 10. Furthermore, with regard to the method, the problem is solved by the subject matter of claim 11. Preferred embodiments of the invention are specified in the dependent claims.

[0013] Accordingly, the control device for an agricultural vehicle is designed with a double-folding distributor boom for applying fertilizers, pesticides, seeds, or the like, and includes, among other things, a control unit and pressure control valves connected to it for adjusting the tilt of the distributor boom. According to the invention, each pressure control valve is associated with a locking valve for locking the distributor boom, and the control unit is assigned a data storage device in which start setpoint pressure values ​​for the pressure control valves, corresponding to different folding states of the distributor boom, and / or electrical control signals corresponding to these start setpoint pressure values ​​are stored. The start setpoint pressure values ​​can also be understood as initial setpoint pressure values.

[0014] The invention offers the advantage that the pressure control valves enable precise pressure control to counteract any unwanted tilting of the distributor linkage. Furthermore, the stored initial target pressure values ​​can be used as a starting point for opening the shut-off valves. Upon unlocking, the tilt control of the distributor linkage can thus be continued in accordance with the current folded position of the linkage, thereby simplifying and improving its precision. The tilt control system can then, so to speak, always set the pressure control valves to the target pressure values ​​corresponding to the current weight distribution on the distributor linkage from the outset and, based on this, quickly and with minimal fluctuations readjust the tilt as desired during operation. Measuring pressure values ​​in the area of ​​the pressure control valves is then unnecessary during operation, particularly for locking / unlocking the distributor linkage.

[0015] The locking valves allow the distributor linkage to be held in a rigid position at all times, thus locking it in place. This is particularly advantageous when driving the agricultural vehicle on a road or when folding and unfolding the distributor linkage. When the locking valves are closed, no fluid can escape from the hydraulic cylinder, and the distributor linkage is locked to the agricultural vehicle. Opening the locking valves unlocks the distributor linkage, allowing its angle relative to the vehicle frame to be adjusted again using the pressure regulating valves.

[0016] In general, the invention has the advantage that the tilt control of the distributor boom can be quickly and precisely adjusted for different folding positions. This ensures a largely homogeneous application of fertilizer, pesticides, or seeds under varying conditions and prevents damage to the distributor boom both during operation and road transport.

[0017] Since opening the shut-off valves can, in principle, lead to uncontrolled movements of the distributor linkage, the tilt setting is advantageously adjusted as precisely as possible from the assigned starting setpoint pressure value when the shut-off valves are opened. This value is preferably set immediately before opening and maintained during opening. In this way, uncontrolled movements of the distributor linkage can be counteracted particularly quickly and efficiently.

[0018] Furthermore, the control unit is configured so that the pressure regulating valves are adjusted to the corresponding start setpoint pressure when the shut-off valves open. This enables particularly precise and stable tilt control.

[0019] Preferably, the pressure regulating valves are designed to maintain a consumer-side pressure depending on an electrical control signal, in particular a control current.

[0020] The pressure regulating valve is, for example, a directly controlled and spring-loaded three-way valve, such as a gate valve. In the de-energized state, i.e., without a control signal, the pressure at the consumer is relieved to the tank. With a maximum control signal, the maximum possible pressure (either from the pressure supply or the maximum value of the pressure regulating valve) is applied to the consumer.

[0021] When a control signal is applied, the spring load in the valve is electromagnetically counteracted, and the pressure on the consumer side is thereby kept constant according to the valve's control characteristic. For example, the set pressure is then proportional to the control signal, which is typically a control current. However, such a proportional control characteristic is not strictly necessary and can be replaced by a non-proportional control, for example, for cost reasons. Any desired control characteristics can be stored in the control unit to calculate and output control signals corresponding to specific target pressure values.

[0022] The valves can, in particular, comprise a valve body with a control piston, a return spring, and a solenoid coil with a magnetic armature for electrical actuation. When an electrical signal is applied via the control unit, the magnetic armature can press against the control piston with a force corresponding to the signal. This allows oil to flow through the valve, increasing or decreasing pressure and thus activating the actuator. This continues until the applied pressure corresponds to the set pressure according to the electrical signal.

[0023] In general, proportional valves operate by regulating a pressure differential. If a preset pressure level is undershot, the valve automatically supplies oil from the hydraulic reservoir until the setpoint is reached again. Conversely, if the pressure level is too high, oil is released. Proportional valves offer efficient control and stability characteristics, as well as low valve hysteresis, which can occur due to friction and magnetization. Furthermore, proportional valves allow for space-saving installation, easy assembly, and replacement. With these valves, the hydraulic pressure in the actuator's cylinder chambers can be adjusted independently, thus actively influencing the angle of the distributor linkage.

[0024] In a preferred embodiment, the pressure control valves are electronically controlled and adjustable to a setpoint based on a known characteristic curve. The characteristic curves describe, for example, the relationship between a given pressure and the corresponding electrical current required at a control coil of the valve. For instance, a setpoint for the pressure control valves can be determined via the pressure sensors, and a control current is then switched to the valves based on the characteristic curve to adjust the corresponding pressure. This has the advantage that the pressure on the manifold can be precisely adjusted to a setpoint via the characteristic curve of the pressure control valves.

[0025] Furthermore, the distributor linkage comprises hinged segments and sensors, in particular potentiometers, at the joints between them for determining the hinged positions. The distributor linkage includes multi-section arms on both sides that can be folded in and out segment by segment and can also assume intermediate positions. The sensors can then preferably detect both fully folded / unfolded segments and intermediate positions at the joints between adjacent segments and transmit the respective hinged position to the control unit. From this, the control unit can determine characteristic hinged positions of the distributor linkage as a whole and assign a start / set pressure value and / or a corresponding control signal to the pressure regulating valves, appropriate to the current hinged position.

[0026] Preferably, the control unit is configured to calculate start target pressure values ​​based on pressure values ​​measured at the consumer end in different folding states of the distributor linkage. These pressure values ​​can have been previously measured on the respective machine or, depending on the device, read from a database and / or entered manually on the control unit.

[0027] Preferably, the control unit is configured to add and / or multiply read start / setpoint pressure values ​​by at least one constant, which is adjustable, in particular, on the control unit. This allows systematic inaccuracies, tolerances, or the like to be taken into account machine-specifically in order to optimize the unlocking / tilt control. These systematic inaccuracies typically do not change, or only change negligibly, during a machine's lifetime and can thus be taken into account simply and effectively.

[0028] Preferably, the control unit for automatically adjusting setpoint pressures, and in particular the initial setpoint pressures, for the pressure regulating valves is configured depending on the type of distributor boom and / or its configuration with application devices. The initial setpoint pressures are largely identical for certain types and configurations. This allows for on-site adjustments and / or updates during commissioning and / or retrofitting.

[0029] Preferably, the control device for automatically adjusting the setpoint pressures, and in particular the start setpoint pressures, of the pressure control valves for intermediate positions of the distributor linkage is designed by, in particular, linear interpolation between the setpoint pressures for the folded and unfolded positions encompassing the respective intermediate position. Intermediate positions can be determined relatively easily using sensors at the joints between the individually foldable segments of the distributor linkage. Thus, the described advantageous unlocking and continuation of the tilt control is also possible if a particular segment could no longer be fully folded or unfolded before locking.

[0030] Furthermore, the pressure regulating valves and the shut-off valves are hydraulic and / or pneumatic valves. This allows for a simple, proven control technology. In principle, however, electromagnetic control elements for tilt control, as well as their locking and unlocking, would also be conceivable.

[0031] Furthermore, the control device includes an actuating element for the distributor linkage connected to the control unit, wherein the actuating element comprises at least one pneumatically and / or hydraulically operating cylinder, in particular a double-acting hydraulic cylinder.

[0032] Such cylinders provide a cost-effective and simple means of returning the distributor linkage to its horizontal starting position when it tilts. The double-acting hydraulic cylinder can, for example, be designed with a piston that can be pressurized on both sides, thus allowing the movement of the distributor linkage to be influenced in opposite directions. The actuator is preferably mounted on a frame to which the distributor linkage is attached and held. The actuator can also be advantageously connected directly to the distributor linkage itself. This has the advantage that the actuator can directly exert a mechanical force on the distributor linkage, ensuring a safe and precise tilt adjustment.

[0033] To put it simply, the pressure regulating valves can have an identical setpoint pressure, in particular 70 - 90 bar, when the distributor linkage is symmetrically unfolded and horizontally aligned, and a setpoint pressure difference when the distributor linkage is asymmetrically unfolded and / or inclined.

[0034] A target pressure differential is also possible if the distributor linkage is folded symmetrically, but the cylinder has pistons and ring areas of different sizes, as is the case with a conventional differential cylinder. When using such an asymmetrical cylinder, it is even conceivable that an almost identical pressure exists on both sides of an asymmetrically folded linkage. It is possible that the area ratio, for example, left to right, is taken into account for an asymmetrical cylinder in the control unit through appropriate programming in the form of a correction factor.

[0035] The following description of an identical target pressure on both sides, i.e., a pressure difference of 0 bar, for symmetrical folding states and a horizontal orientation of the distributor linkage is solely for simplification and illustration purposes. However, this is not a prerequisite for the inventive specification of initial target pressure values ​​depending on the folding states.

[0036] A symmetrically extended distributor linkage generally has the same working width on both sides of the central suspension. Therefore, the same pressure is exerted on the actuator on both sides due to the mass of the distributor linkage on the right and left sides. The pressure difference is thus virtually 0 bar. It is then advisable to set the pressure regulating valves to an identical pressure level and maintain this level.

[0037] If the distributor linkage tilts, the resulting pressure difference at the pressure regulating valves can be adjusted back to the original, identical pressure on both sides via the control device. Therefore, the pressure in the respective cylinder chambers can be increased or decreased equally to return the distributor linkage to its horizontal starting position.

[0038] When the distributor linkage is asymmetrically extended and / or tilted, maintaining the pressure differential prevents the linkage from moving further towards the tilted side. To achieve this, the valves are conveniently controlled by the control unit with an electrical signal to maintain the pressure differential and prevent the distributor linkage from tilting.

[0039] Preferably, the pressure control valves can be independently set and / or adjusted to the same and / or different positions. This means that each of the two pressure control valves can be independently controlled by the control unit via an electronic signal and set to different starting pressure setpoints. Therefore, the control device is efficient for both symmetrical and asymmetrical folding states of the distributor linkage. In asymmetrical folding states with an asymmetrical working width, different pressure conditions inevitably prevail at the two pressure control valves due to the different mass distribution. Their independent adjustability allows even an asymmetrical distributor linkage to be reliably held in the desired, particularly horizontal, position above the ground.

[0040] Preferably, the control unit is designed for tilt control that begins when the shut-off valves open or immediately thereafter. This unit adjusts the pressure on the left and right sides of the actuator by means of the pressure control valves in case of a deviation from the target tilt of the distributor linkage, in order to change the tilt of the distributor linkage, particularly to compensate for and restore the target tilt. This minimizes deviations from the target tilt.

[0041] The invention further claims an agricultural vehicle for spreading materials such as fertilizers, pesticides, or seeds, comprising a distribution boom and a control device according to one of the preceding embodiments. The control device allows for effective adjustment of the distribution boom's inclination relative to the ground. Furthermore, it reduces the risk of uncontrolled movement of the distribution boom, particularly when opening shut-off valves. This ensures homogeneous application of the material.

[0042] Furthermore, the invention claims a method for operating an agricultural vehicle with a distributor boom for applying material such as fertilizer, pesticides and / or seeds, with a control unit and pressure control valves connected thereto for controlling the inclination of the distributor boom, as well as with locking valves for locking the distributor boom.

[0043] Accordingly, for the opening of the shut-off valves, at least one initial target pressure value for the pressure regulating valves, corresponding to the respective folding state of the distributor linkage, is read from a data memory assigned to the control unit. Additionally or alternatively, electrical control signals for the pressure regulating valves, also corresponding to at least one initial target pressure value, can be read from the data memory.

[0044] For this purpose, a target pressure and / or a target control current for the pressure regulating valve can be stored in the control unit. In practical application, there is then a characteristic curve for each pressure regulating valve, which can be used to convert a pressure value into a corresponding current value.

[0045] Furthermore, the pressure regulating valves are set to their respective initial target pressure before the shut-off valves are opened. This minimizes any potential initial corrective movements of the distributor linkage immediately after the shut-off valves are opened.

[0046] Preferably, common and, in particular, side-independent start target pressure values ​​are stored in the data memory for mirror-image asymmetric folding states, and side-specific control signals are calculated from these values ​​depending on the lateral orientation of the respective folding state. For example, start target pressure values ​​are then stored and read only for the distributor linkage folded to the left. For the distributor linkage folded to the right, the start target pressure values ​​can be easily calculated by mirroring the stored values. In the case of a differential cylinder, the cylinder's area ratio can be taken into account. This means that start target pressure values ​​can be recorded and stored for one side. When mirroring these values ​​laterally, the cylinder's area ratio is then considered.

[0047] However, separate start target pressure values ​​for asymmetrically mirrored folding states can also be stored and read from the data memory. In this case, no conversion is necessary to mirror a value stored for one side of the distributor linkage to the other side.

[0048] Preferably, the read and / or calculated left- and right-side start target pressure values ​​are adjusted to a total target pressure difference while maintaining their relative relationship. Only relative values ​​of the start target pressure for the different flap positions then need to be stored. Absolute values ​​of the start target pressure can then be easily adjusted to the respective operating situation based on the predefined total target pressure difference.

[0049] The pressure control valves are preferably electronically controlled and adjusted to the respective setpoint based on a known characteristic curve. This means that setpoints are read from the data storage and, if necessary, converted taking into account correction factors and / or the specified total setpoint pressure difference of the tilt control. Subsequently, the control signal corresponding to the setpoint, particularly in the form of a control current, is switched to the pressure control valves via the known characteristic curve. The valve then switches in such a way that the desired pressure is present on the corresponding side of the actuator. This allows the pressure on the distributor linkage to be precisely adjusted to the respective setpoints on both sides by means of the pressure control valves, and thus the tilt of the distributor linkage can be effectively influenced, taking into account the current folding state.

[0050] In a further preferred embodiment, at least one machine-specific constant is taken into account when determining target pressure values, for example by adding and / or multiplying read-out start target pressure values ​​by the constant. The constant can, for example, be entered manually at the control unit and / or determined as part of a workshop diagnostic. Manufacturing tolerances, hysteresis effects, or the like can thus be taken into account when controlling the system based on the characteristic curve.

[0051] The invention is explained in more detail below with reference to the accompanying schematic drawings. These show: Fig. 1 a detailed section of a distributor linkage on a frame with a control device according to the invention; Fig. 2a - 2d Each a rear view of an agricultural vehicle with a control device and a symmetrical distribution linkage according to an embodiment of the invention, as well as a detailed section of the control device according to Fig. 1 ; Fig. 3a - 3d Each a rear view of an agricultural vehicle with a control device and an asymmetrical distribution linkage according to a further embodiment according to the invention, as well as a detailed section of the control device according to Fig. 1 ; and Fig. 4a - 4d Rear views of an agricultural vehicle with a control device and an asymmetrical distribution linkage according to a third embodiment according to the invention, as well as a detailed section of the control device according to Fig. 1 .

[0052] The Fig. 1 Figure 1 shows a control device 1 for an agricultural vehicle, for example a field sprayer, with a schematically indicated control unit 2 and data storage 3. Also shown is a distributor boom 10 mounted on a frame 11 that can be tilted, for applying material such as fertilizer, pesticides or seeds.

[0053] The control device 1 preferably comprises two pressure regulating valves 18 connected to the control unit 2 for controlling the inclination of the distributor linkage 10, and one locking valve 23 per pressure regulating valve 18 for locking the inclination of the distributor linkage. The locking valves 23 are arranged between the pressure regulating valves 18 and an actuating element 12 for adjusting the inclination of the distributor linkage 10.

[0054] The one in Fig. 1 The frame 11 shown is, by way of example, connected to the agricultural vehicle in a rotationally fixed manner and can expediently be designed to be height-adjustable. The frame 11 forms the suspension for the distributor linkage 10.

[0055] The detailed view shows foldable segments 10a consisting of vertical struts 34 and transverse struts 35, and the central part 10b of the distributor linkage 10. Sensors 36 for determining folding states 4a - 4g are arranged at joints 10c between and between adjacent segments 10a; see the examples in the Fig. 2a - 2c , 3a - 3c and 4a - 4c The sensors 36 can, for example, be potentiometers or the like connected to the control unit 2.

[0056] Each of the folding states 4a - 4g corresponds to a left-side setpoint pressure value 5a - 5g and a right-side setpoint pressure value 6a - 6g for the consumer side of the pressure regulating valves 18 towards the actuator 12. The inclination of the distributor linkage 10 is adjusted by the actuator 12, where essentially the two setpoint pressure values ​​5a - 5g and 6a - 6g are applied. The actuator 12 is mechanically connected directly to the frame 11 on one side and directly to the distributor linkage 10 on the other.

[0057] The actuating element 12 is designed, for example, as a double-acting hydraulic cylinder comprising a piston 13 in a housing 15, which can be pressurized on both sides. Piston rods 14 are arranged on both sides of the piston 13. One of the two piston rods 14 is mechanically connected to the frame 11. The other piston rod 14 has a free end. The force transmission from the frame 11 to the distributor linkage 10 is therefore carried out directly by the actuating element 12.

[0058] In general, the actuator can also be formed by a cylinder, which has a different surface area on the left side than on the right side. For example, a cylinder is conceivable that has a ring surface and a piston surface with different areas. Different effective pressure areas on the left and right piston sides are then taken into account by appropriately programmed pressure adjustments in the control unit 2.

[0059] For force transmission and thus for tilt adjustment, the actuator 12 is connected to a hydraulic circuit 16. The hydraulic circuit 16 is an open circuit comprising a hydraulic reservoir 25 and a pump 17. Two pressure control valves 18 are arranged between the pump 17 and the hydraulic reservoir 25 on one side and the actuator 12 on the other. In other words, the pressure control valves 18 connect the pump 17 and the hydraulic reservoir 25 on the consumer side to the two pressure sides 20, 22 of the actuator 12. For this purpose, the hydraulic circuit 16 has first and second supply lines 19, 21 between the actuator 12 and the respective pressure control valve 18.

[0060] The pressure control valves 18 receive a left-side electrical control signal 7a-7g and a right-side control signal 8a-8g from the control unit 2, specifically in the form of a control current, corresponding to a characteristic curve of the pressure control valves 18 stored in the control unit 2 and the respective right-side setpoint pressure value 5a-5g and left-side setpoint pressure value 6a-6g. The pressure control valves 18 then maintain both consumer-side pressures at the respective setpoint pressure values ​​5a-5g and 6a-6g. The setpoint pressure values ​​5a-5g and 6a-6g can be assigned in pairs to the folding states 4a-4g of the distributor linkage 10.

[0061] The target pressure values ​​5a - 5g, 6a - 6g and / or the control signals 7a - 7g, 8a - 8g are stored in data memory 3 and can be calculated using machine-specific constants and / or application-specific measured values, such as current inclination values ​​for the distributor linkage 10. For example, the target pressure values ​​5a - 5g, 6a - 6g can be combined in pairs to form a predefined total target pressure difference.

[0062] The Figuren 2a - 2c Each figure shows a schematic rear view of a machine 31 designed as a field sprayer. The field sprayer can be towed by a tractor, be self-propelled, or be mounted on an agricultural vehicle. Figuren 2a - 2c What they have in common is that the machine 31 includes a distribution boom 10 and a storage container 30, in which material to be distributed, such as fertilizer, pesticides or seeds, is housed.

[0063] The distributor linkage 10 has spray nozzles arranged along its underside. These spray nozzles can be connected to a pump and the reservoir 30 via a hose system.

[0064] The distributor linkage 10 is advantageously designed to be foldable for road traffic, for adjusting partial working widths and / or for driving around obstacles.

[0065] The Fig. 2a - 2c They differ in the width of the distributor linkage 10. Here, in Fig. 2a The distributor linkage 10 is fully unfolded according to a first folding state 4a. It comprises, for example, three folding segments 10a on each side of the linkage. Fig. 2b Figure 1 shows the distributor linkage 10 with its crossbars 35 and vertical bars 34 in a second folded state 4b with the outermost segments 10a folded in on both sides. Fig. 2c According to a third folding state 4c, the two outer segments 10a are folded in on both the left and right sides.

[0066] The distributor linkage 10 is centrally suspended from a frame of the machine 30. The overall inclination of the distributor linkage 10, i.e., the extended, straight distributor linkage 10, can be adjusted by the control device 1.

[0067] Fig. 2d This shows a detailed section of the control device according to Fig. 1 with the set pressure conditions for the distributor linkage 10, which is symmetrically mounted in the folding states 4a - 4c. The pressure difference Δp between the left-hand first pressure side 20 and the right-hand second pressure side 22 of the piston 13 is then zero. Both pressure sides are therefore set to the same pressure. For a symmetrically mounted distributor linkage 10, this pressure can, for example, be between 70 and 90 bar.

[0068] In contrast, when using a differential cylinder, a pressure difference would exist. The corresponding pressure ratio would then be the inverse of the area ratio of the piston and ring areas.

[0069] The Fig. 3a - 3c Each figure schematically shows a rear view of machine 31, which is configured as a field sprayer. The field sprayer is similar to the one in Fig. 2 equipped with a distribution boom 10 and a storage container 30 in which the material to be applied is housed. Figuren 3a - 3c They differ in the working width of the distributor boom 10. The distributor boom 10 is in Fig. 3a exemplified by three segments 10a formed on both sides of the storage container 30, corresponding to the folding state 4a.

[0070] In Fig. 3b Only two segments 10a are unfolded on the right side, since the outer segment 10a is in the folded state. This corresponds to a fourth folding state 4d.

[0071] In Fig. 3c Only one segment 10a on the right side is unfolded, while the two outer ones are folded in. This corresponds to a fifth folding state 4e.

[0072] The distributor linkage 10 is therefore asymmetrically mounted in the folding states 4d, 4e, since in the Figuren 3b und 3c The number of segments 10a on both sides of the storage container 30 is not the same when unfolded. Generally, for an asymmetrical distributor linkage 10, the number of unfolded segments 10a, or more generally, the working width, differs on both sides.

[0073] Similarly, an asymmetrical distributor linkage can exist if a specific joint 10c is neither fully folded nor fully extended, i.e., is in an intermediate position. Intermediate positions can be detected by the sensors 36 and / or the folding angle between the articulated segments 10a can be measured.

[0074] In folding states 4d and 4e, a pressure difference Δp typically occurs. This arises because the distributor linkage 10 has a different mass distribution on the right and left sides. This different mass distribution could also occur in the symmetrically mounted distributor linkage 10 in folding state 4a according to Fig. 3a This can occur, for example, if there is a leftward tilt. The overall tilt of the distributor linkage 10 can be adjusted by the control device 1.

[0075] Fig. 3d This shows a detailed section of the control device 1 according to Fig. 1 with the set pressure conditions for the asymmetrically mounted or left-leaning distributor linkage 10. The pressure difference Δp between the left-side first pressure side 20 and the right-side second pressure side 22 of the actuator 12 is greater than zero. Therefore, the pressure on the left side is greater than the pressure on the right side.

[0076] Should, for example, after only partial unfolding or folding of the distributor linkage 10, i.e. in a situation such as in the folded state 4e according to Fig. 3c In order to prevent an abrupt sagging of the distributor linkage 10 after opening the shut-off valves 23 when the shut-off valves 23 are closed, i.e., when unlocking the distributor linkage 10, the valves 18 are expediently controlled by the control unit 1 with an electrical signal in such a way that the pressure difference is maintained after opening the shut-off valves 23 and the inclination of the distributor linkage 10 does not change when the shut-off valves 23 are opened.

[0077] For this purpose, the pressure regulating valves 18 are set to suitable initial target pressure values. This ensures that when the distributor linkage 10 is unlocked, the pressure prevailing between the shut-off valves 23 and the respective side of the actuator 12 is at least approximately also present in front of the respective shut-off valve 23 when the shut-off valves 23 are opened.

[0078] The Figuren 4a - 4c Each figure schematically shows a rear view of machine 31, which is configured as a field sprayer. The field sprayer is similar to the one in Fig. 2 It is designed and includes a distribution boom 10 and a storage container 30 with material to be applied. Figuren 4a - 4c They differ in the working width of the distributor boom 10. The distributor boom 10 comprises in Fig. 4a For example, three foldable segments 10a on both sides of the storage container 30.

[0079] In a sixth folding state 4f according to Fig. 4b On the left side, there are only two unfolded segments 10a; the outer segment 10a is folded in. In a seventh folding state 4g according to Fig. 4c Only one segment 10a is unfolded on the left side; the two outer segments 10a are folded in.

[0080] The distributor linkage 10 is therefore, as in the Figuren 3b und 3c , asymmetrically mounted, since in the folding states 4f and 4g of the Figuren 4b und 4c The storage container 30 does not have the same number of unfolded segments 10a on both sides. Therefore, a pressure difference Δp also occurs. The pressure difference Δp can also be demonstrated, for example, in the folded state 4a according to... Fig. 4a With a symmetrically mounted distributor linkage 10, this occurs when a rightward tilt is present. The overall tilt of the distributor linkage 10 can, in turn, be adjusted by the control device 1.

[0081] Fig. 4d This shows a detailed section of the control device according to Fig. 1 with the set pressure conditions for the asymmetrically mounted or right-side inclined distributor linkage 10 according to Fig. 4a - 4c The pressure difference Δp between the left-hand first pressure side 20 and the right-hand second pressure side 22 of the actuator 13 is negative. Therefore, the pressure on the left side is lower than the pressure on the right side. To prevent the distributor linkage 10 from moving downwards on the right side when the shut-off valves 23 are opened, this pressure difference must advantageously be maintained by the pressure regulating valves 18 when the shut-off valves 23 are opened.

[0082] In general, the control device 1 can be used efficiently for inclination control and prevention of uncontrolled movements for symmetrical or asymmetrical distributor linkages with any working width.

[0083] In particular, the control device 1 is designed such that the pressure control valves 18 are set at least approximately to the associated initial target pressure values ​​5a - 5f, 6a - 6f at the time the shut-off valves 23 are opened, i.e. for example, for the folding state 4d to the initial target pressure values ​​5d and 6d for the left and right side of the distributor linkage 10.

[0084] This prevents, for example, an asymmetrical unfolding of the distributor linkage 10, as in Fig. 4a - 4c As shown, with the shut-off valves 23 closed, the distributor linkage 10 performs an uncontrolled clockwise movement after the shut-off valves 23 are opened, or in a situation according to Fig. 3a - 3c a counterclockwise movement.

[0085] The pressure control valves 18 are set to their associated initial setpoint pressure values ​​5a - 5f, 6a - 6f by the control unit 2 applying the corresponding control signals 7a - 7g, 8a - 8g to the pressure control valves 18.

[0086] As the Fig. 3a - 3d and 4a - 4dAs shown in the comparison, there are mirror-image, asymmetrical arrangements of the distributor linkage 10 with reversed sides. Therefore, it would generally be sufficient to determine and store the corresponding initial target pressure values ​​5d and 6d, as well as 5e and 6e, only for the folding states 4d and 4e. For the mirror-image corresponding folding states 4f and 4g, the initial target pressure values ​​5f and 6f, as well as 5g and 6g, would then be applied in reverse. The same applies to the corresponding control signals 7f and 8f, as well as 7g and 8g. In the case of a differential cylinder, the different cylinder areas on the left and right sides would also have to be taken into account, as described above.

[0087] The principle of control-related mirroring of folding states 4d - 4g can also be applied to other, not shown, folding states, including those with at least one intermediate position between adjacent segments 10a. It would then only be necessary to store a simplified, side-independent data set for different folding states and then apply it to the respective side orientation of the folding state, i.e., to mirror it if necessary.

[0088] Additional target pressure values ​​for intermediate positions of joints 10c between adjacent segments 10a can also be stored and / or calculated. For example, separate target pressure values ​​for suitable angular intervals at the joints 10c could be stored and / or calculated. Interpolation between fully folded and unfolded adjacent segments 10a is also practical. For example, linear interpolation for specific angular intervals at a joint 10c and / or between fully folding and unfolding, especially of the outermost segment 10a, would be conceivable.

[0089] When calculating target pressure values ​​5a - 5g, 6a - 6g, systematic machine-related corrections using constants are possible, as are dynamic corrections, for example, due to the current inclination of the distributor linkage 10 during its locking / unlocking. The necessary inclination sensors are known and can be easily evaluated by the control unit 2.

[0090] Such constants are taken into account, for example, by addition and / or multiplication when calculating the target pressure values ​​5a - 5g, 6a - 6g and / or the control signals 7a - 7g, 8a - 8g in the control unit 2.

[0091] Typically, a practical total setpoint pressure differential is specified for actuating the actuator 12 and maintained during operation when controlling the pressure regulating valves 18. Accordingly, the setpoint pressure values ​​5a - 5g, 6a - 6g or the control signals 7a - 7g, 8a - 8g are raised or lowered as pairs of values ​​with a constant ratio from left to right so that they add up to the total setpoint pressure differential.

[0092] This allows for largely uniform pressure conditions to be established at the actuating element 12 during operation. In particular, when unlocking the distributor linkage 10, i.e., when opening the shut-off valves 23, jerky tilting movements of the distributor linkage 10 can be avoided, and the tilt control can continue at a suitable initial setpoint pressure and a corresponding consumer-side pressure.

[0093] The initial target pressure values ​​5a - 5g, 6a - 6g and / or 7a - 7g, 8a - 8g can be stored in the control unit 2 specifically for different types and configurations of distributor booms 10 with application devices or the like. Accordingly, the described tilt control can be quickly adapted to specific machine configurations.

Claims

1. Control device (1) for an agricultural utility vehicle with a distributor boom (10) that can be folded on both sides for spreading material, such as fertilizer, plant protectant or seed, comprising a control unit (2) and pressure control valves (18) connected thereto for controlling the inclination of the distributor boom (10), wherein each pressure control valve (18) is assigned a check valve (23) for locking the distributor boom (10), and the control unit (2) is assigned a data memory (3), in which initial target pressure values (5a-5g, 6a-6g) of the pressure control valves (18) assigned to different folding states (4a-4g) of the distributor boom (10) and / or electrical control signals (7a-7g, 8a-8g) assigned to the initial target pressure values (5a-5g, 6a-6g) are stored, wherein the pressure control valves (18) and the check valves (23) are hydraulic and / or pneumatic valves, wherein the control device (1) comprises an actuator (12), which is connected thereto, for the distributor boom (10), wherein the actuator (12) comprises at least one pneumatically and / or hydraulically operating cylinder, wherein the control unit (2) is configured such that the pressure control valves (18) are adapted to the associated initial target pressure (5a-5g, 6a-6g) when the check valves (23) are opened, and wherein the distributor boom (10) comprises foldable segments (10a) and, at joints (10c) located therebetween, sensors (36) for determining the folding states (4a - 4g).

2. Control device according to claim 1, wherein the pressure control valves (18) are designed to maintain a consumer-side pressure depending on an electrical control signal (7a-7g, 8a-8g), in particular a control current.

3. Control device according to either of the preceding claims, wherein the sensors (36) for determining the folding states (4a - 4g) are potentiometers.

4. Control device according to any of the preceding claims, wherein the control unit (2) is configured to measure and / or input pressure values for different folding states (4a - 4g) and to calculate initial target pressure values (5a-5g, 6a-6g) on the basis thereof and to assign them to the folding states of the distributor boom (10).

5. Control device according to any of the preceding claims, wherein the control unit (2) is configured to add and / or multiply read-out initial target pressure values (5a-5g, 6a-6g) with at least one in particular adjustable constant.

6. Control device according to any of the preceding claims, wherein the control unit (2) is configured to automatically adapt the initial target pressure values (5a-5g, 6a-6g) for the pressure control valves (18) depending on the type of distributor boom (10) and / or its equipment with spreader elements.

7. Control device according to any of the preceding claims, wherein the control unit (2) is designed to automatically adapt the initial target pressure values of the pressure control valves (18) for intermediate positions of the distributor boom (10), in particular by linear interpolation between the target pressure values (5a-5g, 6a-6g) for the fully folded / unfolded positions between which the intermediate position is present.

8. Control device according to any of the preceding claims, wherein the actuator (12) comprises a double-acting hydraulic cylinder.

9. Control device according to any of the preceding claims, wherein the control unit (2) is designed for inclination control which starts during and / or directly after the check valves (23) are opened, and which adjusts the left-hand and righthand pressure on the actuator (12) by means of the pressure control valves (18) in the event of a deviation from a target inclination, in order to change the inclination of the distributor boom (10), in particular in a compensatory manner to restore the target inclination.

10. Agricultural utility vehicle for spreading material, such as fertilizer, plant protectant or seed, having a distributor boom (10) and a control device (1) according to any of the preceding claims.

11. Method for operating an agricultural utility vehicle with a distributor boom (10) for spreading material, such as fertilizer, plant protectant or seed, comprising a control unit (2) and pressure control valves (18) connected thereto for controlling the inclination of the distributor boom (10) as well as check valves (23) for locking the distributor boom (10), wherein the distributor boom comprises foldable segments (10a) and, at joints (10c) located therebetween, sensors (36) for determining folding states (4a - 4g) of the distributor boom (10), wherein the pressure control valves (18) and the check valves (23) are hydraulic and / or pneumatic valves, wherein the control device (1) comprises an actuator (12), which is connected thereto, for the distributor boom (10), wherein the actuator (12) comprises at least one pneumatically and / or hydraulically operating cylinder, wherein for opening the check valves (23) at least one initial target pressure value (5a-5g, 6a-6g) for the pressure control valves (18) assigned to the particular folding state (4a - 4g) of the distributor boom (10) is read out from a data memory (3) assigned to the control unit (2), and wherein the pressure control valves (18) are set to the associated initial target pressure (5a-5g, 6a-6g) before the check valves (23) are opened.

12. Method according to claim 11, wherein common starting target pressure values (5d-5g) are stored in the data memory (3) for asymmetric folding states (4d - 4g) corresponding to one another in mirror image, and side-specific control signals (7d-7g, 8d-8g) are calculated therefrom depending on the lateral orientation of the particular folding state (4d - 4g).