CONTROL AND / OR REGULATING SYSTEM FOR AN AGRICULTURAL IMPLEMENT

Description

[0001] The invention relates to a control and / or regulation system for an agricultural device. Furthermore, the invention relates to an agricultural device and a method for controlling and / or regulating an agricultural device.

[0002] Such devices are used for agricultural equipment for spreading materials such as fertilizers, pesticides, or seeds, for example, in field sprayers. To spread the material efficiently and widely on the field soil to be worked, the agricultural equipment features a distribution boom with multiple application elements, such as spray nozzles. The distribution boom extends transversely to the direction of travel and can have working widths of up to 40 m. The distance between the distribution boom and the ground should remain as constant as possible across the entire working width of the distribution boom. This means that the distribution boom is held as parallel as possible to the soil to be worked.

[0003] As is known, the distribution boom has a central section, for example a centrally located frame, and two lateral booms connected to the central section with several boom sections connected by joints that can be folded in towards each other in the transport position and unfolded into the working position. The individual boom sections can be pivoted about vertical axes via the associated joints and are mounted so they can rotate about the respective vertical axis. Using the fold-out boom sections, the distribution boom can thus be transferred from a space-saving transport position to a working position. The transport position describes the folded state of the distribution boom in which the lateral booms are completely folded towards the central section. In contrast, the working position describes the state of the distribution boom in which all boom sections are unfolded.In other words, the distribution boom has the entire working width in the working position.

[0004] When operating an agricultural implement with such a large working width, vibrations of the distributor boom in or opposite to the direction of travel can occur, for example due to driving over uneven ground, acceleration or braking of the implement or a commercial vehicle pulling or carrying the implement. Such vibrations can result in very high forces occurring on the distributor boom, and homogeneous material application can no longer be guaranteed. It is therefore known, for example from EP 2 829 177 B1, to arrange adjusting and / or damping means between the central section and the booms, or between the boom sections, in such a way that the distributor boom can be moved from a transport position to a working position and vice versa, and vibrations occurring on the distributor boom in the direction of travel can be dampened.The actuating and / or damping means can, for example, be designed as hydraulic cylinders. Vibrations in the distributor rods create pressure differences in the hydraulic cylinders.

[0005] It has now been shown that known damping systems operate unreliably under driving conditions where it is unavoidably necessary to transfer forces from the device to the distribution linkage, such as during sharp acceleration or braking of the device, or when cornering. Other relevant prior art documents are DE102017104814A1, EP2907385A1, WO2015 / 055680A1, WO2015 / 067804A1, and EP3064061A1.

[0006] The invention is therefore based on the object of providing an improved control and / or regulation system for an agricultural implement in which a precise damping of vibrations occurring in or opposite to the direction of travel can be achieved.

[0007] This object is achieved by a control and / or regulating system according to claim 1. Preferred embodiments are described in the dependent claims.

[0008] The hydraulic device according to the invention can be a hydraulic device by which the distribution rod assembly can be transferred from a transport to a working position and vice versa. However, it can also be a hydraulic device that is independent of a device for transferring the distribution rod assembly from a transport to a working position and vice versa.

[0009] According to the invention, to generate the control signal for the hydraulic device, both pressure values ​​applied to a respective hydraulic device and a determined position of the respective boom relative to the center section are taken into account. The determined position is also taken into account when processing the pressure values. In other words, the current position of the boom is included in the generation of the control signal, and the position also influences the processing of the pressure values. For example, it can be determined whether the boom is in a position where vibration damping is desired, i.e., in a normal working position, or whether vibration damping is not desired, i.e., the boom is not in its normal working position.In particular, this allows for the consideration of external forces that occur during a driving condition, such as cornering, sudden braking or acceleration, or similar, since these forces are directly reflected in a change in the detected position. This prevents a conflict between the damping control based on pressure measurements and the control based on the detected position during a driving condition in which external forces act on the device.

[0010] The first sensor device can comprise one or more sensors. The sensors of the first sensor device can be designed as pressure sensors for direct pressure measurement, in particular as pressure transducers. Such a design as a pressure sensor has the advantage that both a relative pressure and an absolute pressure can be determined. Furthermore, the sensors can preferably be designed as differential pressure transducers for determining a differential pressure or an occurring pressure difference. Advantageously, the pressure transducers can detect the pressure to be measured via a measuring diaphragm, which is mechanically deformed depending on the respective pressure. This mechanical change is measured electronically and output as an analog output signal and transmitted to the data processing unit. The sensor device can also comprise a combination of sensors of different types.

[0011] The second sensor device can comprise one or more sensors. The sensors of the second sensor device can be designed as potentiometers. The potentiometer determines whether an individual rod section or the entire boom is deflected from its desired position, in particular its working position, in the direction of travel, and how its position or orientation changes. Additionally or alternatively, the second sensor device can comprise sensors designed to determine a position parameter of the respective hydraulic device. For example, such a position parameter can be the travel, i.e. the position of the piston, of the double-acting hydraulic cylinder. By determining this parameter, it can be determined how far the hydraulic cylinder is extended or retracted. This correlates directly with the position of the respective boom relative to the center section.

[0012] The data processing unit can be configured to process the signals from the first sensor device using a first controller, in particular a first PID (proportional-integral-derivative) controller, and to generate the control signal based on the output of the first controller. In other words, the data processing unit can be configured to control the respective hydraulic device such that a target pressure prevails at the respective hydraulic device. Alternatively or additionally, the data processing unit can be configured to process the signals from the second sensor device using a second controller, in particular a second PID controller, and to generate the control signal based on the output of the second controller.The data processing unit can therefore be configured to control the respective hydraulic device in such a way that a target position of a respective boom relative to the central part is maintained.

[0013] The data processing unit can be configured to reduce the influence of the signals of the first sensor device on the generation of the actuating signal if a deviation of the determined position from a target position is greater than or equal to a first predetermined value.

[0014] The target position can be identified, for example, by a target angle, with the deviation from the target position being determined by the angular difference between the target angle and a determined angle. An angle difference is defined as the absolute value of the difference between two angles. An angle difference can be measured directly using suitable sensors. However, it can also be determined, for example, by the data processing unit, by calculating the difference between two measured angle values.

[0015] Alternatively or additionally, the target position can be identified by a target position parameter of the hydraulic system. In this case, the deviation from the target position can be determined by the difference between the target position parameter and a measured position parameter.

[0016] In particular, the data processing unit can be configured to continue to take the output value of the first controller into account. For example, the data processing unit can be configured to reduce the influence of the signals from the first sensor device on the control signal only if the deviation is greater than or equal to the first predetermined value and if the output value of the first controller would lead to an increase in the deviation. In contrast, the data processing unit can be configured not to reduce the influence of the signals from the first sensor device on the control signal if the deviation is greater than or equal to the first predetermined value, but the output value of the first controller would lead to a reduction in the deviation.

[0017] For example, the target position can be a target angle, and the deviation can be an angle difference. The first predetermined value can, for example, be in the range of 0.1° to 0.9°, preferably in the range of 0.2° to 0.6°. By reducing the influence of the signals from the first sensor device, i.e., the pressure values, on the control signal in these cases, the effect of the vibration damping can be at least partially mitigated until the target angle is reached again. In other words, the vibration damping can be suppressed until the agricultural implement has returned to its "normal" working position.

[0018] For example, a target angle can be the desired angle between the boom and the center section in the working position, for example, 90°. If the actually measured angle lies within an angular interval of (target angle - first predetermined value) to (target angle + first predetermined value), for example, within an interval of 89.1° to 90.9°, the data processing unit can be configured not to reduce the influence of the signals from the first sensor device on the control signal. In other words, the vibration damping is fully effective within this angular interval. If the measured value lies outside this interval, the data processing unit can be configured to reduce the effect of the vibration damping depending on the output value of the first controller.

[0019] If the measured angle lies outside the above-mentioned interval, the data processing unit can further check whether the value output by the first controller leads to an increase or decrease in the angle. In the following, it is assumed that a negative output value results in a control signal that causes the respective boom to unfold and an increase in the angle. A positive output value then analogously results in a control signal that causes the respective boom to fold in and a decrease in the angle. Of course, the data processing unit can also be configured so that a negative output value leads to folding in and a positive output value leads to unfolding of the respective boom.

[0020] For example, the measured angle may be 91°, i.e., greater than the target angle. If the first controller outputs a negative value in this case, i.e., a value that would increase the angle, the data processing unit can be configured to reduce the effect of the vibration damping. If, on the other hand, the first controller outputs a positive value, the data processing unit can be configured to leave the effect of the vibration damping unchanged.

[0021] If the measured angle is smaller than the target angle, for example, 89°, the same applies, but with the opposite sign. Therefore, if the first controller outputs a positive value in this case, the data processing unit can be configured to reduce the effect of the vibration damping. If, on the other hand, the first controller outputs a negative value, the data processing unit can be configured to leave the effect of the vibration damping unchanged.

[0022] It should be noted at this point that the above applies analogously to the case where the target position and the deviation are each characterized by a target position parameter of the respective hydraulic device or the difference between the target position parameter and the determined value of the position parameter. In this case, corresponding values ​​and intervals of the position parameter are used in the control system instead of the described angle values ​​and intervals. In particular, the influence of the signals from the first sensor device on the control signal can be reduced in direct proportion to the deviation. In other words, the greater the detected deviation, the more the influence of the pressure measurements on the generation of the control signal can be reduced.

[0023] For example, the influence of the signals from the first sensor device on the control signal can be reduced by reducing the maximum output value of the first controller. Alternatively or additionally, it is also possible to reduce a control factor of the first controller.

[0024] Furthermore, the data processing unit can be configured not to take into account the values ​​of the first sensor device when generating the actuating signal if a deviation of the determined position from a target position is greater than or equal to a second predetermined value.

[0025] As described above, in this case too the target position can be characterized, for example, by a target angle and / or by a target position parameter of the hydraulic device.

[0026] Here, too, the data processing unit can be configured to take the output value of the first controller into account when generating the control signal. For example, the data processing unit can be configured to reduce the influence of the signals from the first sensor device on the control signal only if the deviation is greater than or equal to the second predetermined value and if the output value of the first controller would lead to an increase in the deviation. In contrast, the data processing unit can be configured not to reduce the influence of the signals from the first sensor device on the control signal if the deviation is greater than or equal to the second predetermined value, but the output value of the first controller would lead to a reduction in the deviation.

[0027] For example, the target position can be a target angle and the deviation an angle difference. The second predetermined value can, for example, be in the range of 1° to 5°, preferably in the range of 1.2° to 1.8°. In the case of a larger deviation between the target angle and the determined angle, it is advantageous to completely suppress the damping control until the device has approximately returned to the "normal" working position. To achieve this, for example, the maximum output value of the first controller can be reduced to 0 in these cases. Alternatively or additionally, a control factor of the first controller can be reduced to 0. In such cases, it is also possible not to transmit the output signal of the first controller, or a signal otherwise generated based on the signals from the first sensor device, to the hydraulic device.

[0028] If the actually measured angle lies outside an angular interval of (target angle - second predetermined value) to (target angle + second predetermined value), for example, outside the angular interval of 88° to 92°, the data processing unit can be configured to check whether the first controller outputs a positive or negative value. The above statement regarding the possible signs of the output value applies analogously here.

[0029] For example, the measured angle may be 93°, which is greater than the target angle. If the first controller outputs a negative value in this case, the data processing unit can be configured to suppress the effect of the vibration damping. If, however, the first controller outputs a positive value, the data processing unit can be configured to leave the effect of the vibration damping unchanged.

[0030] If the measured angle is smaller than the target angle, for example 88°, the same applies, but with the opposite sign. If the first controller outputs a positive value in this case, the data processing unit can be configured to suppress the effect of the vibration damping. If, on the other hand, the first controller outputs a negative value, the data processing unit can be configured to leave the effect of the vibration damping unchanged. The above applies analogously to the case in which the target position and the deviation are each characterized by a target position parameter of the respective hydraulic device or the difference between the target position parameter and the determined value of the position parameter. In this case, corresponding values ​​and intervals of the position parameter are used in the control system instead of the described angle values ​​and intervals.

[0031] The data processing unit can further be configured to limit the output value of the first and / or second controller to a maximum value. This can be done, in particular, independently of the signals from the first and / or second sensor device. This can prevent the generation of a control signal that could lead to an excessively violent movement of the respective boom.

[0032] The first sensor device may be configured to detect a pressure associated with a pressure on the side of an annular surface of a respective hydraulic cylinder.

[0033] Furthermore, the first sensor device can be configured to detect a pressure associated with a common pressure on the sides of the annular surfaces of all hydraulic cylinders. For example, the first sensor device can be configured to detect the pressure in a hydraulic line of the system that supplies the annular-side chambers of all hydraulic cylinders of the system with hydraulic fluid. Such an arrangement simplifies the system by reducing the total number of required sensors.

[0034] The respective hydraulic device may further comprise a hydraulic line which is connected to the hydraulic cylinder for supplying hydraulic fluid, as well as at least one hydraulic valve unit for regulating the hydraulic pressure, wherein the valve unit is controllable via a control signal from the data processing unit.

[0035] The hydraulic device can generally be designed as an actuator to convert the electrical control signals from the data processing unit into a mechanical movement, thus transferring the distributor rod from a transport position to a working position and ensuring the damping of vibrations occurring on the distributor rod in the direction of travel. The hydraulic valve unit advantageously provides reliable and fast-acting overload protection for the hydraulic cylinder. Overall, the hydraulic pressure at the hydraulic cylinder can be optimally adjusted using the hydraulic valve unit, which can be controlled by the data processing unit using a control signal.

[0036] The hydraulic line connected to the respective hydraulic cylinder can be connected to at least one hydraulic accumulator. It is conceivable that the control and / or regulation system comprises a central hydraulic accumulator, or alternatively, a hydraulic accumulator is assigned to each of the right-hand and left-hand booms of the distribution linkage. The hydraulic accumulator advantageously generates the hydraulic pressure acting in the hydraulic cylinder.

[0037] It is possible for the hydraulic systems assigned to each boom to form a closed hydraulic circuit, with the hydraulic cylinders of the hydraulic systems connected via a common hydraulic line. Ideally, this eliminates the need for separate hydraulic lines. Furthermore, in this case, a common sensor for detecting any pressure changes occurring in the hydraulic systems can also be attached to the common hydraulic line.

[0038] The at least one hydraulic valve unit can be formed by a proportional valve. In particular, it can be a 4-way valve. It can also be a 2-way valve. The hydraulic valve unit can also be formed, for example, by a pressure control valve or other circuits for changing the applied hydraulic pressure in the hydraulic device.

[0039] Furthermore, the hydraulic valve unit can be electronically controlled and adjusted based on a known characteristic curve. The characteristic curve of the valve unit generally reflects the functional dependence of the output signal on the input signal. Ideally, the output signal changes linearly with the pressure occurring as the input signal. The ideal characteristic curve would therefore be a straight line. However, the measured, or in other words the actual, characteristic curve of the hydraulic valve unit cannot be exactly linear; rather, even at the start and end points of the pressure range, the output signals can deviate from the respective ideal values. Therefore, for precise adjustment of the damping of vibrations occurring on the distributor rod, it is advantageous to adjust the hydraulic valve unit based on its characteristic curve and thus adapt it to and counteract the occurring pressure change.For example, the pressure sensors can be used to determine, based on the characteristic curve of the valve unit, how large the required control current must be switched to the valve unit in order to counteract the pressure change that occurs.

[0040] The data processing unit can form a single unit with the sensor device and the respective hydraulic devices. This implies a direct connection, for example, via cable or wirelessly, between the sensor unit and the data processing unit, as well as the hydraulic device. Therefore, the measurement signal acquired by the sensor device can be transmitted efficiently and as quickly as possible to the hydraulic vibration damping device via a control signal from the data processing unit.

[0041] Furthermore, the at least one hydraulic valve unit of the respective hydraulic device of one boom can be set and / or adjusted by the control and / or regulating system independently of the hydraulic valve unit of the respective hydraulic device of the other boom. This means that the hydraulic valve unit of the associated hydraulic device of the respective boom can be controlled independently via an electronic signal from the data processing unit. Therefore, the control and / or regulating system can be efficiently used for both symmetrical and asymmetrical distribution booms.

[0042] The invention further provides an agricultural implement for applying material, such as fertilizers, crop protection agents, or seeds, comprising a control and / or regulating system. The control and / or regulating system can have one or more of the features described above. The agricultural implement can, in particular, be a field sprayer. The field sprayer can be self-propelled. It can also be a towed or mounted field sprayer.

[0043] The invention further provides a method for controlling and / or regulating an agricultural implement. The agricultural implement has a distributor boom for distributing material, such as fertilizer, pesticide, or seed, which extends transversely to the direction of travel. It comprises a central section and two lateral booms connected to the central section, each with several boom sections connected by joints that can be folded toward one another in the transport position and unfolded in the working position. Each boom is assigned at least one hydraulic device, allowing the distributor boom to be transferred from a transport position to a working position and vice versa.The respective hydraulic device can also be controlled to dampen vibrations occurring on the distributor rod in the direction of travel, and the respective hydraulic device comprises a hydraulic cylinder, in particular a double-acting hydraulic cylinder. The method comprises the following steps: . Detecting a pressure change at the respective hydraulic device caused by vibrations of the distribution rod using a first sensor device. Determining the position of one of the booms relative to the center section using a second sensor device. Generating, based on the detected pressure change and the determined position, a control signal for the respective hydraulic device, wherein the signals from the first sensor device are processed taking the determined position into account.

[0044] The procedure may further include the following steps: Processing the signals from the first sensor device and / or the second sensor device using a controller, in particular a PID controller. Generating the control signal based on the controller output.

[0045] Furthermore, in the method, the influence of the signals of the first sensor device on the generation of the control signal can be reduced if a deviation of the determined position from a target position is greater than or equal to a first predetermined value.

[0046] Furthermore, in the method, the signals of the first sensor device may not be taken into account when generating the control signal if a deviation of the determined position from a target position is greater than or equal to a second predetermined value.

[0047] The control and regulation system may have one or more of the features described above.

[0048] Further features and advantages of the invention are explained below with reference to the exemplary figures. Herein: Fig. 1 schematically shows a distributor rod assembly with a control and / or regulating system and with a central section and two lateral arms connected to the central section in a top view; Fig. 2 schematically shows a detailed view of a distributor rod assembly with a control and / or regulating system and with a central section and two lateral arms connected to the central section; Fig. 3 schematically shows a control circuit diagram for a control and / or regulating system; Fig. 4 schematically shows a control circuit diagram for a control and / or regulating system; Figs. 5a and 5b schematically show the curve of a maximum output signal of a controller and the curve of a control factor; Fig. 6 schematically shows angular ranges for the control; Fig. 7 schematically shows a hydraulic circuit diagram for a control and / or regulating system according to one embodiment; Fig. 8 schematically shows a hydraulic circuit diagram for a control and / or regulating system according to a further embodiment; and Fig.9 schematically shows a hydraulic circuit diagram for a control and / or regulating system according to a further embodiment.. .

[0049] Fig. 1 shows a schematic plan view of a distributor boom 12 for use with a control and / or regulating system according to the invention for an agricultural implement. The agricultural implement is designed here as a field sprayer. The distributor boom 12 serves to spread material, such as fertilizer, pesticide, or seed, and extends transversely to the direction of travel. The distributor boom 12 has a central section 2 and two lateral booms 3 connected to the central section 2, each with a plurality of boom sections 4 connected by joints that can be folded toward one another in the transport position and unfolded in the working position.

[0050] Fig. 2 shows a schematic detailed view of the Fig. 1 shown distributor rod 12. It can be seen that the right and left boom 3 are each assigned a hydraulic cylinder 10 a, b, which is connected to the middle section 2 and the respective boom 3. By means of the respective hydraulic cylinder 10 a, b, the respective boom 3 and thus the distributor rod 12 can be transferred from a transport position into a working position. The hydraulic cylinders 10 a, b fold the distributor rod 12 via vertical axes into the working and transport position. In order to transfer the boom completely from the transport to the working position, further devices can be provided, which are in Fig. 1 and Fig. 2 are not shown. For example, each rod section 4 can be assigned a further hydraulic cylinder that can fold and / or unfold the respective rod section 4.

[0051] In the following, the term "fully deployed" is used in reference to a boom 3 in such a way that, in this state, the angle between the boom 3 and the center section 2 is 90°. If the angle is less than 90°, the boom 3 is not fully deployed. If the angle is greater than 90°, the boom 3 is deployed too far.

[0052] Sensors (not shown) for detecting the working position of the distribution rod can be installed in the area of ​​the hydraulic cylinders 10 a, b. For example, the sensors can be designed as potentiometers. This allows the position or working position of the piston rod of the hydraulic cylinder to be determined. A corresponding measurement or position signal can be transmitted via a data line to a data processing unit (not shown), which controls the folding process of the rod sections based on the measurement signal. The data processing unit is configured in such a way that the signals from the sensors can be processed and, on this basis, a control signal for the hydraulic cylinders can be generated. Thus, the unfolding process of the distribution rod can be detected using the potentiometers for position detection.

[0053] When the distributor rod is in the working position, or in other words completely unfolded, any vibrations occurring on the distributor rod can be dampened by the control and / or regulating system via the hydraulic cylinders 10 a, b, and the distributor rod 12 can be held as far as possible in its desired position. The desired position of the distributor rod 12 is characterized by the fact that no relative movement occurs between the commercial vehicle carrying the distributor rod and the distributor rod itself, particularly in the direction of travel. In particular, in the desired position, no relative movements occur due to vibrations of the distributor rod in the direction of travel. It should be noted that the desired position is an idealized position that cannot be achieved constantly or only briefly during operation with active damping.

[0054] For this purpose, the control and / or regulating system comprises sensors (not shown) which are designed such that a pressure change at the hydraulic cylinders 10 a, b occurring due to vibrations of the distributor rod 12 can be determined. In particular, a pressure difference at the respective hydraulic cylinder 10 a, b can be measured by means of the sensors 15 a, b, which are preferably designed as pressure sensors. Alternatively, the sensors 15 a, b can be designed as force sensors. Based on the measurement signals from the pressure sensors, the data processing unit can control a hydraulic valve unit (not shown) assigned to the respective hydraulic cylinder 10 a, b, whereby pressure equalization and thus damping of the vibrations occurring can be achieved.

[0055] Fig. 3 shows a block diagram of a possible embodiment of a control and evaluation program of a data processing unit according to Fig. 2 It can be seen that the circuit diagram comprises two main arms. The upper arm describes the control system's regulation of the angle between a boom and the central section. It can be seen that the setpoint of the angle between one of the booms and the central section is compared with an actual value of this angle. In this example, the difference between the values ​​is calculated. The result of the comparison is passed as the actual value to a first PID controller whose setpoint is 0. In other words, the first PID controller compares the measured angle difference with the value 0. The first PID controller is configured in a known manner such that it continuously compares the setpoint with the actual value and, from the difference between the two variables, i.e. the control deviation, determines a first signal in order to minimize the control deviation. It is indicated that the first signal can be further modified.This can happen, for example, depending on a measured position of the distributor rod 12.

[0056] The lower arm of the block diagram describes the control of the vibration damping, which is based on the measured pressures at the hydraulic device, more specifically at the annular surface and the piston surface of the hydraulic cylinder. It is shown that the measured pressure at the annular surface is compared with the measured pressure at the piston surface. The pressure at the annular surface is previously corrected using a pressure offset. The pressure offset takes into account external forces acting on the hydraulic cylinder when the distributor rod is in its nominal position, for example, in its working position. Such forces can occur, for example, due to driving on slopes or a non-symmetrically deployed distributor rod. The pressure offset can be stored as a fixed value in the data processing device. It can also be changed by the user.It is also possible for the pressure offset to be dynamically adjusted during operation of the agricultural implement based on the measured pressure values. After correcting the measured pressure with the pressure offset, the corrected value is further corrected by the ratio of the piston area to the annular area, or more precisely, multiplied. Since the force acting on an area is the product of the area and the pressure acting on it, the corrected pressure on the annular area can then be directly compared with the pressure on the piston area.

[0057] For example, the piston surface is larger than the annular surface by a factor of K, for example, by a factor of 2. If a pressure of 90 bar acts on the annular surface, the pressure at the piston surface would be lower than that at the annular surface in equilibrium, in this example, 45 bar.

[0058] The difference between the corrected pressure on the ring surface and the pressure on the piston surface is then calculated, and this value is then passed on to a second PID controller as the actual value, the setpoint of which is 0. In other words, the second PID controller compares the measured pressure difference, with the pressure on the ring surface corrected as described above, with the value 0. The second PID controller is configured in a known manner to continuously compare the setpoint with the actual value and to determine a second signal from the difference between the two variables in order to minimize the control deviation.

[0059] In Fig. 3 It can also be seen that the second signal can be further modified, in particular limited. This can be done, in particular, depending on the measured angle, as described further below in connection with Figs. 4a and 4b. In addition, however, a limitation can also be provided that is independent of the measured angle. For example, it is possible to limit the value of the second signal to a maximum value that is never exceeded.

[0060] Using the first signal from the upper arm and the second signal from the lower arm, a control signal is generated and transmitted to the hydraulic system. In response to the control signal, the respective hydraulic valve is activated to fold or extend the respective boom.

[0061] Fig. 4 shows an example of the lower arm of the block diagram from Fig. 3 , where the logic of the second PID controller is shown in more detail. It can be seen that in the PID controller, a distinction is made as to whether the actual value is positive or negative. Depending on this distinction, in the example shown, P, I, and D components of the controller are modified with a factor K1 for positive values ​​and K2 for negative values. Using the values ​​K1 and K2, all of the P, I, and D components can be influenced simultaneously. In general, it can be said that in the present example, the P component is sufficient for the control of the open-loop control. The first PID controller in the upper arm of the Fig. 3 shown block diagram can be designed similarly.

[0062] The Fig. 3 The modification shown can be implemented in various ways. For example, the maximum output value of the controller can be limited in a known manner. Alternatively or additionally, it is possible to adjust the values ​​K1 and K2, thus influencing the controller's control factors.

[0063] These possibilities are in the Fig. 5a und 5b illustrated. Fig. 5a shows an example of the possible course of a maximum output signal of the second PID controller from Fig. 3 depending on the measured flap angle. It can be seen that below a first flap angle, here 90.5°, the controller output constantly has a maximum value of -6000 ml / min. In the range between 90.5° and 92°, this value is continuously reduced until it reaches the value 0. This means that at a flap angle greater than 92°, the output signal of the second PID controller is equal to 0, and therefore the lower arm of the Fig. 3 shown block diagram no longer influences the control. This means that no vibration damping occurs, and the control signal is determined by the upper arm of the circuit diagram, i.e., by the angle control.

[0064] Fig. 5b illustrates the analogous case where not the maximum output value of the PID controller, but a control parameter, in particular the parameter for the P component, is adjusted. Below a folding angle of 90.5°, the value is constantly equal to 500. In the range between 90.5° and 92°, the value decreases continuously. Above a folding angle of 92°, the value is equal to 0. This in turn results in the lower arm of the Fig. 3 shown block diagram no longer influences the control. It is possible that the parameter P can also be adjusted using the value K1 or K2.

[0065] The Fig. 5a und 5b illustrate a case where the measured angle is greater than a certain value. However, it is understood that the same applies to the case where the measured angle is smaller than a certain value. This will be explained later with reference to Fig. 6 It should be noted that the values ​​shown for the first folding angle of 90.5° and the second folding angle of 92° are merely examples.

[0066] While in the Fig. 5a und 5b While a linear curve of the maximum output signal or the control parameter between the first and second folding angles is shown, other curves are also possible. The curve can also be characterized by a nonlinear function. It can also have a stepped curve.

[0067] Fig. 6 schematically shows various angle ranges and the control values ​​used in the angle ranges in the exemplary control. Five different folding angle ranges are illustrated here as examples. The first range 501 is an angular interval around the target angle of the distributor rod, in this case 90°. This interval comprises the angle values ​​from 89.5° to 90.5°, inclusive. In the first range 501, there is no limitation of the maximum output signal or of a control parameter. In other words, in this range, the damping control can act freely on the hydraulic cylinder. The second range 502, the angular interval, covers the angular interval from 90.5° (exclusive) to 92° (inclusive). In this range, control of the hydraulic valve by the damping control, which leads to the folding out of the rod, is limited by a limitation of the minimum control value and / or the control parameter K1.If the controller's result is positive, meaning the rods are folding in, no limit is applied. This is because in this case, the damping control and the angle control act in the same direction, since the rods are extended further than desired.

[0068] The third range 503 encompasses the angular interval from 89.5° (exclusive) to 88° (inclusive). In this range, the control of the hydraulic valve by the damping control, which leads to the folding of the boom, is limited by a limitation of the maximum control value and / or the control parameter K2. If the result of the controller is negative, i.e., if it tends to unfold the boom, no limitation occurs. This is due to the fact that in this case, the damping control and the angle control control in the same direction, since the boom is unfolded less than desired.

[0069] The fourth range 504 includes all angles greater than 92°. In this range, the minimum control value and / or the control parameter K1 are limited to 0. This means that no vibration damping is performed, which would lead to the rods folding out. If the controller result is positive, i.e., if it tends toward the rods folding in, no limitation occurs for the reasons stated above.

[0070] The fifth range 505 includes all angles smaller than 88°. In this range, the maximum control value and / or the control parameter K2 are limited to 0. This means that no vibration damping is performed, which would lead to the rod folding. If the controller result is negative, i.e., tends toward the rod unfolding, no limitation occurs for the reasons stated above.

[0071] The Fig. 6 bis 8 show schematic representations of a hydraulic circuit diagram for a control and / or regulation system. Various hydraulic circuit diagrams are shown as examples. Please note that additional components may be present but are not shown in the figures for the sake of simplicity of the schematic layout.

[0072] Fig. 7 represents a hydraulic circuit diagram for a hydraulic device according to an embodiment of the invention for the pressurization of the right and left hydraulic cylinders 10 a, b according to Fig. 2 for transferring the distributor rod from a transport position to a working position and for adjusting the damping of vibrations occurring on the distributor rod in the direction of travel. The right and left hydraulic cylinders 10 a, b are designed as double-acting hydraulic cylinders. The hydraulic cylinders 10 a, b are connected to the distributor rod according to Fig. 2 as described above. The hydraulic cylinders 10a, b are connected to a hydraulic reservoir (not shown) via the hydraulic line 17. The hydraulic reservoir contains a hydraulic fluid that can be supplied to the respective hydraulic cylinder 10a, b via the hydraulic line 17. The hydraulic line 17 is formed by a pressure line, which is designated by the reference symbol P in the figures, and a hydraulic reservoir line, which is designated by the reference symbol T.

[0073] Two pressure sensors 15a, b are each assigned to the right and left hydraulic cylinders 10a, b. The two pressure sensors 15a, b are assigned to the hydraulic cylinder in such a way that a pressure can be determined both on a piston surface and on an annular surface of the hydraulic cylinder 10a, b. The hydraulic cylinder 10a, b has two different sized effective surfaces on the two sides of the piston 11. The effective surface of the hydraulic cylinder facing the piston rod is smaller than the effective surface facing away from the piston rod. Accordingly, the pressure sensor 15a on the annular surface measures a different, in particular greater, pressure than the pressure sensor 15b on the piston surface.

[0074] The pressure sensors 15a, b are connected to a supply line 17a and a discharge line 17b of the respective hydraulic cylinder 10a, b to measure the pressure at the annular and piston surfaces of the hydraulic cylinder 10a, b. Within the scope of the application, the supply line 17a of the hydraulic line 17 describes that section of the hydraulic line 17 that connects the hydraulic reservoir (not shown) to the annular surface of the hydraulic cylinder 10a, b. In contrast, within the scope of the application, the discharge line 17b of the hydraulic line 17 describes that section of the hydraulic line 17 that connects the hydraulic reservoir to the piston surface of the hydraulic cylinder 10a, b.

[0075] The pressure sensors 15 a, b are designed, for example, as pressure transducers. The pressure transducer generally represents an electrical transducer for measuring the existing pressure in the hydraulic cylinder 10 a, b. Thus, a pressure change caused by vibrations in the distributor rod can be determined using the pressure sensor. For example, the pressure transducers 15 a, b can be used to measure a pressure difference at the hydraulic cylinder 10 a, b and thus at the hydraulic system.

[0076] Furthermore, each hydraulic cylinder 10 a, b is assigned a hydraulic valve unit for regulating the hydraulic pressure. The hydraulic valve unit is arranged in the hydraulic line 17 and is designed, for example, as a proportional valve 16, or in other words, as a multi-way valve. The pressure sensors 15 a, b assigned to the respective hydraulic cylinder 10 a, b are arranged on the supply line 17a and discharge line 17b between the hydraulic cylinder 10 a, b and the associated proportional valve 16. The proportional valve 16 is specifically designed as a 4 / 3-way valve. The proportional valve 16 can be controlled and adjusted by a data processing unit (not shown). For this purpose, the proportional valve 16 is connected to the data processing unit, for example via cables or wirelessly. The data processing unit is also connected to the pressure sensors 15 a, b.Based on the signals detected by the pressure sensors 15 a, b, the data processing unit can control the proportional valve 16. In particular, the proportional valve 16, which is assigned to the respective hydraulic cylinder 10 a, b, can be controlled for pressure equalization based on the values ​​detected by the pressure sensors 15 a, b. In the rest position of the proportional valve 16, the valve is preferably closed, or in other words, in a central position. The valve can be deflected to the left or right via the data processing unit. By deflecting the valve, the pressure on the annular surface or the piston surface of the hydraulic cylinder can be increased or decreased by means of the proportional valve, or in other words, the piston of the hydraulic cylinder 10 a, b can be extended or retracted.

[0077] The data processing unit, the pressure sensors 15a, b, and the hydraulic valve unit 16 of the hydraulic system form a single unit. Thus, based on the signals detected by the pressure sensors 15a, b, the data processing unit and the proportional valves for pressure equalization in the hydraulic cylinders 10a, b can dampen vibrations occurring in the distributor rod.

[0078] Fig. 8 shows a further schematic representation of a hydraulic circuit diagram for a control and / or regulating system according to the invention according to a further embodiment. As with reference to Fig. 7 described are the right and left hydraulic cylinders 10 a, b for folding the right and left side boom 3 of the distribution rod 12 according to Fig. 1 and for damping vibrations occurring on the distributor rod 12, for example, as double-acting hydraulic cylinders 10 a, b and connected to a hydraulic line 17. To measure the hydraulic pressure on the ring and piston surface of the respective hydraulic cylinder 10 a, b, two pressure sensors 15 a, b are provided for each hydraulic cylinder 10 a, b as described with reference to Fig. 7 described.

[0079] A check valve 19 can be arranged in the respective supply line 17a of the hydraulic line 17 in the respective hydraulic cylinder 10a, b, between the hydraulic reservoir (not shown) and the respective hydraulic cylinder 10a, b. The check valve 19 can be designed as a check valve and spring-loaded. By means of the check valve 19, the flow can be blocked in one direction and released in the opposite direction. Accordingly, hydraulic pressure can be continuously applied to the annular surface of the respective hydraulic cylinder 10a, b.

[0080] A multi-way valve 18b is arranged in the respective discharge line 17b of the respective hydraulic cylinder 10a, b. The hydraulic pressure is measured with the pressure sensor 15b between the hydraulic cylinder 10a, b and the multi-way valve 18b. The multi-way valve 18b can be electronically controlled via the data processing unit for pressure equalization based on the measurement signals from the pressure sensor 15a, b.

[0081] The supply line 17a and the discharge line 17b are connected by an additional intermediate line 17c. A further multi-way valve 18a is arranged in the intermediate line 17c. The multi-way valve 18a can be controlled electronically by the data processing unit. Furthermore, a shut-off valve 19 can be arranged on the side of the multi-way valve 18a facing the discharge line 17b.

[0082] The two multi-way valves 18a serve to connect the ring and piston surfaces of the respective hydraulic cylinders 10a, b. To extend the hydraulic cylinder 10a, b, the ring and piston surfaces are connected to each other, or the hydraulic cylinder extends over the relatively larger area of ​​the piston surface. In other words, when the respective multi-way valve 18a is actuated by the data processing unit, the respective hydraulic cylinder 10a, b can extend.

[0083] The retraction of the respective hydraulic cylinder 10 a, b can be achieved by means of the multi-way valve 18 b assigned to the respective hydraulic cylinder 10 a, b. When the multi-way valve 18 b is actuated by the data processing unit, hydraulic fluid can be drained from the piston side of the hydraulic cylinder 10 a, b. Due to the continuous supply of hydraulic pressure to the annular surface of the hydraulic cylinder 10 a, b, the hydraulic cylinder 10 a, b can thus retract.

[0084] To ensure identical forces can be generated when extending and retracting the hydraulic cylinder 10 a, b, the ratio between the ring and piston area should ideally be 1:2. Thus, based on the values ​​measured by the pressure sensors 15 a, b, which are evaluated and processed by the data processing unit, the extension and retraction of the hydraulic cylinder 10 a, b can be efficiently controlled via the electronically controlled folding and unfolding of the two multi-way valves 18 a, b.

[0085] Fig. 9 shows a further schematic representation of a hydraulic circuit diagram for a control and / or regulating system according to the invention according to a third embodiment. The basic structure and the functioning of the individual components of the hydraulic circuit diagram are as described with reference to Fig. 8 described. In contrast to Fig. 8Only a single pressure sensor 15a is arranged in the hydraulic line 17 for measuring the pressure on the annular surface of both hydraulic cylinders 10a, b. Accordingly, the single pressure sensor 15a is arranged in the hydraulic line 17 between the hydraulic reservoir (not shown) and the respective supply line 17a of the respective hydraulic cylinder 10a, b. In other words, the single pressure sensor 15a is connected to the pressure line of the hydraulic line 17, which is designated in the figures by the reference symbol P and includes the supply line 17a. Should the pressure on the annular side of the hydraulic cylinder 10a, b increase during operation, the hydraulic fluid within the supply line 17a is pressed against the shut-off valve 19.In other words, the hydraulic fluid column rests on the check valve 19, and the actual pressure on the annular surface of the hydraulic cylinder 10a, b is higher than the pressure measured by the pressure sensor 15a. Consequently, the multi-way valve 18a or the multi-way valve 18b can be opened to equalize the pressure. This equalizes the pressures in the pressure line and the annular surface of the hydraulic cylinder 10a, b, since in both cases, hydraulic fluid can flow from the pressure line.

[0086] It is understood that the features mentioned in the previously described embodiments are not limited to these specific combinations and are also possible in any other combinations. Furthermore, it is understood that the geometries shown in the figures are merely examples and are also possible in any other configurations.

Claims

1. Open-loop and / or closed-loop control system for an agricultural apparatus having a distributor boom (12) for spreading material, such as fertilizer, plant protectant, or seed, which extends transversely to the direction of travel and has a central part (2) and two lateral arms (3) which are connected to the central part (2) and have a plurality of boom portions (4) which are connected by joints and can be folded in toward one another in the transport position and unfolded in the working position, each arm (3) being associated with at least one hydraulic device, it being possible for each hydraulic device to be actuated to damp vibrations occurring on the distributor boom (12) in the direction of travel, and each hydraulic device comprising a hydraulic cylinder (10a,b), in particular a double-acting hydraulic cylinder, the open-loop and / or closed-loop control system comprising: a first sensor device which is configured to detect a pressure change occurring at the relevant hydraulic device caused by vibrations of the distributor boom (12); a second sensor device which is configured to determine a position of each arm (3) relative to the central part (2); and a data processing unit which is configured to process signals from the sensor device and the second sensor device and to generate a control signal for the relevant hydraulic device on the basis of these signals, characterized in that the data processing device is designed to process the signals from the first sensor device, taking into account the determined position, in such a way that, in a driving state in which external forces act on the apparatus, conflict is prevented between the damping control based on the pressure measurements and the control based on the determined position.

2. Open-loop and / or closed-loop control system according to claim 1, wherein the data processing unit is configured to process the signals from the first sensor device by means of a controller, in particular a PID controller, and to generate the control signal on the basis of the output of the controller.

3. Open-loop and / or closed-loop control system according to claim 1 or 2, wherein the data processing unit is configured to reduce the influence of the signals from the first sensor device upon the generation of the control signal, in particular taking into account the output of the controller, if a deviation of the determined position from a target position is greater than or equal to a first predetermined value.

4. Open-loop and / or closed-loop control system according to any of the preceding claims, wherein the data processing unit is configured not to take into account the signals from the first sensor device when generating the control signal, in particular taking into account the output of the controller, if a deviation of the determined position from a target position is greater than or equal to a second predetermined value.

5. Open-loop and / or closed-loop control system according to any of the preceding claims, wherein the first sensor device is configured to detect a pressure associated with a pressure on the side of an annular surface of each hydraulic cylinder (10 a,b).

6. Open-loop and / or closed-loop control system according to any of the preceding claims, wherein the first sensor device is configured to detect a pressure associated with a common pressure on the side of the annular surfaces of all hydraulic cylinders (10 a,b).

7. Open-loop and / or closed-loop control system according to any of the preceding claims, wherein each hydraulic device further comprises: a hydraulic line (17) which is connected to the hydraulic cylinder (10 a,b) for supplying hydraulic fluid; and at least one hydraulic valve unit (16) for controlling the hydraulic pressure, wherein the valve unit (16) is controllable via a control signal from the data processing unit.

8. Open-loop and / or closed-loop control system according to claim 7, wherein the at least one hydraulic valve unit (16) is formed by a proportional valve.

9. Open-loop and / or closed-loop control system according to any of the preceding claims, wherein the hydraulic device can transfer the distributor boom (12) from a transport position to a working position, and vice versa.

10. Agricultural apparatus for spreading material, such as fertilizer, plant protectant or seed, having an open-loop and / or closed-loop control system according to any of the preceding claims.

11. Method for open-loop and / or closed-loop control of an agricultural apparatus having a distributor boom (12) for spreading material, such as fertilizer, plant protectant, or seed, which extends transversely to the direction of travel and has a central part (2) and two lateral arms (3) which are connected to the central part (2) and have a plurality of boom portions (4) which are connected by joints and can be folded in toward one another in the transport position and unfolded in the working position, wherein each arm (3) is associated with at least one hydraulic device, as a result of which the distributor boom (12) can be transferred from a transport position to a working position, wherein each hydraulic device can be actuated to damp vibrations occurring on the distributor boom in the direction of travel, and wherein each hydraulic device comprises a hydraulic cylinder (10 a,b), in particular a double-acting hydraulic cylinder, wherein the method comprises the following steps: detecting a pressure change occurring at the relevant hydraulic device caused by vibrations of the distributor boom (12) by means of a first sensor device; determining a position of one of the arms (3) relative to the central part (2) by means of a second sensor device; and generating, on the basis of the detected pressure change and the determined position, a control signal for the relevant hydraulic device, wherein the signals from the first sensor device are processed, taking into account the determined position, in such a way that, in a driving state in which external forces act on the apparatus, conflict is prevented between the damping control based on the pressure measurements and the control based on the determined position.

12. Method according to claim 11, further comprising the steps of: processing the signals from the first sensor device, in particular a PID controller; and generating the control signal on the basis of the output of the controller.

13. Method according to claim 11 or 12, wherein the influence of the signals from the first sensor device upon the generation of the control signal, in particular taking into account the output of the controller, is reduced if a deviation of the determined position from a target position is greater than or equal to a first predetermined value.

14. Method according to any of claims 11 to 13, wherein the signals from the first sensor device are not taken into account when generating the control signal, in particular taking into account the output of the controller, if a deviation of the determined position from a target position is greater than or equal to a second predetermined value.