AGRICULTURAL FLUID APPLICATION SYSTEM

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates to an agricultural fluid application system. Agricultural fluid application systems are used to apply an agricultural fluid in agriculture or in fruit or vegetable cultivation, whereby the fluid can be, for example, water, fertilizer, an insecticide, or any other fluid or fluid mixture. The agricultural fluid application systems have an agricultural fluid container in which the agricultural fluid to be applied can be stored. The agricultural fluid container is connected to at least one field sprayer via a conveying device, in particular a pump. The agricultural fluid can be applied to an agricultural area via the field sprayer. For this purpose, conventional field sprayers have a valve for controlling the flow through the field sprayer and a nozzle via which a spray cone, a desired droplet pattern, or a spray mist can be generated.To apply the agricultural fluid to larger areas, several such field sprayers can be arranged side by side or distributed across an area. The agricultural fluid application system is preferably mounted on a tractor, a trailer, or an attachment. In this case, several field sprayers can be arranged on a spray boom, distributed laterally in the direction of travel, so that when the tractor is moving, the field sprayer can apply the agricultural fluid over a width determined by the width of the spray boom.During operation of the agricultural fluid application system, an electronic control device regulates the operation of the conveying device and / or the at least one field spraying device in order to adapt the flow rate, pressure, application behavior of the field spraying device, and thus the distribution and quantity of the agricultural fluid on the soil, according to the conditions. For environmentally harmful agricultural fluids, the application rate should be kept as low as possible, and for agricultural fluids that promote plant growth, the application rate should be within a narrow, specified range. Such field spraying devices are known, for example, from documents EP 3 338 547 B1, GB 2 423 227 A, GB 2 571 268 A, and US Pat. No. 8 640 972 B2. OBJECT OF THE INVENTION

[0002] The present invention is based on the object of developing an agricultural fluid application system with regard to operational safety, control and regulation options, protection against contamination and the resulting wear and / or blockages, protection against incorrect operation and / or application behaviour to improve. SOLUTION

[0003] The object of the invention is achieved according to the invention with the features of the independent patent claim. Further preferred embodiments of the invention can be found in the dependent patent claims. DESCRIPTION OF THE INVENTION

[0004] The invention is based on the observation that contaminants, for example in the form of foreign particles, sludge, or precipitating components, can lead to functional impairments in agricultural fluid application systems. If the contaminants accumulate in the area of ​​valve bodies or valve seats, this can result in the valves not fulfilling the desired closing function or in an actual opening cross-section deviating from the desired opening cross-section. On the other hand, the contaminants can lead to damage to the valve bodies or valve seats, seals, etc. Finally, the contaminants can accumulate at any flow cross-section, for example, in a supply line, which can lead to altered flow cross-sections and associated undesirable flow conditions.For this reason, filters are installed in conventional agricultural fluid application systems to capture the contaminants. The filters can then be replaced or flushed at specified intervals or as needed, depending on the extent of capture. However, practice shows that, despite the use of filters, the agricultural fluid application system is not adequately protected against adverse effects during operation. In practice, the agricultural fluid application system uses non-agricultural fluids to which sufficiently pure water, for example, from a local mains supply, has been added.Rather, for reasons of cost and / or practicality, water is often added to the agricultural fluid, which may be taken from a well or stream, thus introducing contaminants, particularly sand, into the agricultural fluid application system, which may then lead to the aforementioned impairments despite the filters or clog and / or damage the filters.

[0005] According to the invention, the agricultural fluid is filtered by at least one filter on its way from the conveying device to the field spraying device (basically in accordance with the prior art). However, the agricultural fluid does not then flow directly from the filter to the field spraying device. Instead, a police filter device is arranged between the filter and the at least one field spraying device.

[0006] A "police filter device" is a device known from general process engineering. It is located downstream of a filter or separator and performs a safety function. This safety function is automatically activated when an upstream filter or separator is no longer capable of proper filtering (e.g., due to damage or blockage) or when an undesirable change in the flow conditions occurs as a result of damage or blockage to the filter. Activation of the safety function can consist in detecting the failure of the upstream filter or separator. The safety function can also consist in the police filter at least temporarily taking over the filtering or separation for the upstream filter or separator, for example, in the event of damage to the upstream filter or separator.Optionally, it is possible (in addition to the aforementioned safety functions) for the police filter to have a final cleaning function even when the upstream filter or separator is filtering or separating properly, so that the police filter also performs partial or residual filtration even when operating properly. It is possible for the police filter to have coarser or the same filtering characteristics as an upstream filter or separator, so that the police filter does not retain any contaminants when the upstream filter or separator is operating properly. If the police filter also performs a final cleaning function, the police filter can also have finer filter characteristics than the upstream filter or separator, or the police filter can be suitable for the final cleaning function for filtering a different type of contaminant than the upstream filter or separator.

[0007] The use of a police filter according to the invention is applicable both when there is only one filter or separator within the supply line between the conveying device and the at least one field spraying device or when there are several filters or separators, wherein in the latter case some or all of the filters or separators can be arranged upstream of the police filter.

[0008] The police filter device can be designed as a distributed device with individual components that can then be connected to one another via electrical and / or fluid lines. Preferably, the police filter device is designed as a police filter unit, in which the components can be integrated into a multi-part housing with corresponding connections. It is also possible for such a police filter unit to be designed modularly with several components flanged together.

[0009] In principle, all police filter devices known from the prior art and intended for other purposes can be used, with any filter materials, single- or multi-stage filters and / or separators, collection chambers, pressure-controlled bypass lines, etc. For a particular proposal of the invention, the police filter device has an inlet pressure sensor and / or an outlet pressure sensor and / or a flow meter. The signals from the inlet pressure sensor, the outlet pressure sensor, and / or the flow meter can be used for the aforementioned safety function, for example, to detect whether the police filter device has "started," which can indicate improper operation of the upstream filter or separator.On the other hand, the signals from the inlet pressure sensor, the outlet pressure sensor, and / or the flow meter can be used to control or regulate the operation of components of the agricultural fluid application system. For example, the flow meter of the pressure filter device can be used to control the operation of the conveying device to achieve a desired flow rate. Alternatively or cumulatively, the field spraying device can be controlled based on the flow meter signal, so that the desired application rate and application behavior (spray cone, droplet size) are controlled or regulated. Accordingly, the signal from the inlet pressure sensor can also be used to control a pressure relief valve and / or the operation of the conveying device, and / or a signal from the outlet pressure sensor can be used to control the at least one field spraying device.

[0010] According to another agricultural fluid application system according to the invention, the control filter device has an inlet pressure sensor and an outlet pressure sensor. An electronic control device, which is also responsible for controlling or regulating the operation of the conveying device and / or the field spraying device, or a specific electronic control device of the control filter device then determines a pressure difference between the signals of the inlet pressure sensor and the outlet pressure sensor. Monitoring is then carried out, either alone or based on this pressure difference, on the basis of which, in particular, improper operation of the at least one upstream filter or separator can be detected. This embodiment is based on the observation that the control filter device has a defined flow behavior when the upstream filter or separator is operating properly.For example, if the filter characteristics of the police filter device are coarser than those of the upstream filter or separator, the agricultural fluid flows through the police filter device without significant filtration or separation, resulting in a small pressure difference. However, if the upstream filter or separator fails, contaminants (filtered out during proper operation) reach the police filter device, where these contaminants are then separated. The separation of these contaminants then leads to an increase in the pressure difference, so the change in the pressure difference provides information about the function of the upstream filter or separator.

[0011] It is possible that the police filter device also includes a flow meter. Under certain circumstances, for the same filtration or separation efficiency at the police filter device (and thus for the same degree of impairment of the upstream filter or separator), the pressure difference between the inlet pressure sensor and the outlet pressure sensor depends on the flow rate through the police filter device. The invention takes this observation into account by modeling the dependence of the pressure difference on the flow rate measured by the flow meter. The modeling may include only the aforementioned dependence or also the dependence on additional parameters.

[0012] Such a model can, for example, consist of a mathematical single- or multi-parameter model, a curve, or a characteristic map. If monitoring is then performed, the monitoring depends not only on the pressure difference between the inlet pressure sensor and the outlet pressure sensor, but also on the model. Such a model can, for example, be stored in a memory unit or a volatile memory of an electronic control unit (or the aforementioned control unit).

[0013] The monitoring result can be a simple binary result ("upstream filter or separator is operating properly" or "downstream filter or separator is not operating properly"), or the monitoring result can be an evaluation of the effectiveness of the upstream filter or separator in stages or continuously. Depending on the monitoring result, and in particular the assignment of the result to one of the binary stages, one of the multiple stages, or the exceeding of a threshold value by a continuously variable result, appropriate action can then be taken using control electronics and the control logic located therein.

[0014] The following are only a few examples of possible measures that do not limit the invention: It is possible that a signaling device is activated, for example, a display on a screen, a warning light, or a warning tone. This can be used to signal to an operator of the agricultural fluid application system, such as a tractor driver, that the filter or separator, and thus the agricultural fluid application system, is not working properly. It is also possible that the action consists of generating an error entry. Such an error entry can then be used for documentation purposes. It is also possible that the error entry is used by the manufacturer of the agricultural fluid application system or a component thereof to assess warranty or guarantee claims.Based on the monitoring results and the error entry made on this basis, it can also be proven that the agricultural fluid application system was operated with a contaminated agricultural fluid that does not meet the specifications, which can then be used to ward off warranty or guarantee claims. Another possible measure is to regulate the operation of the pump. For example, if improper operation is detected, the pump's operation can be automatically restricted or stopped. However, it is also possible that, in the event that the filter or separator is damaged and the safety function of the police filter is activated, the desired application behavior requires a different pump output, which can thus be brought about based on the monitoring results.It is also possible that, if improper operation of the filter or separator is detected, the pump is specifically activated to ensure emergency operation, for example, with reduced application of the agricultural fluid. It is also possible that, depending on the monitoring results, a change in the control or regulation of the field spraying system may be implemented as a measure. For example, if improper operation of the upstream filter or separator is detected, the field spraying system may be controlled to a partially or fully open position so that it can be flushed with the agricultural fluid and any deposits of contaminants that have already accumulated there can be flushed out.It is also possible, however, that the field spraying system is deliberately closed when improper operation is detected in order to prevent further operation of the field spraying system and to prevent damage that could arise from further operation. To give just one further example, in the normal case of proper operation the valve of the field spraying system can be operated using pulse width modulation. Conversely, if improper operation of the upstream filter or separator is detected, the operation of the valve can be switched to a proportional valve by bringing about a constant change in the opening cross-section of the valve or a change that is merely slower than the pulse width modulation. Another possible measure is to change the operating position of a valve in the supply line and / or return line.Here, the supply line refers to a fluid line from the agricultural fluid tank via the conveying device to at least one field spraying device, via which agricultural fluid is supplied to the field spraying device for application. In contrast, a return line refers to a fluid line that leads from the field spraying device back to the agricultural fluid tank in order to return excess fluid supplied to the field spraying device that cannot be applied back to the agricultural fluid tank. This can then be done, for example, by changing a flow cross-section in one of the lines, a throttle cross-section, or similar measures. It is possible to change the limiting pressure of a pressure relief valve in one of the lines.It is also possible for a valve arranged in the supply line and / or return line to be moved into a blocking position in order to change or terminate the operation of the agricultural fluid application system. Another possible measure is for an automatic flushing of the police filter device to be initiated, terminated, controlled and / or regulated by the control logic. In this case, the flushing can occur, for example, when a threshold value of the monitored pressure difference is exceeded, or the duration and / or extent of the flushing flow can be dependent on the pressure difference. It is possible that after flushing operation has been initiated, for example for a predetermined flushing duration and / or a predetermined flushing flow, the automatic flushing of the police filter device is terminated and the pressure difference is then determined again.If the pressure difference then indicates that the filter system has been sufficiently freed of contaminants by the flushing operation, normal operation can continue without a flushing flow. Otherwise, a new flushing operation may be initiated and / or error entries may be generated, a change in the operation of the pump and / or the at least one field spraying device may occur, or the operation of the agricultural fluid application system may be terminated or controlled.

[0015] The above measures can individually, in any number and combination or all

[0016] be used in the agricultural fluid application system according to the invention.

[0017] To prevent misuse of the agricultural fluid application system when used without the police filter device (e.g., to reduce the sensitivity of the agricultural fluid application system to possible contamination (at the risk of damage) and, for example, to enable operation with the addition of water from a well to the agricultural fluid, which is not desired by the manufacturer), the invention proposes that an electronic control unit have an inlet pressure sensor connection, an outlet pressure sensor connection, and / or a police filter connection. For proper operation of the agricultural fluid application system with a police filter device, signals from the police filter device are fed to the inlet pressure sensor connection, the outlet pressure sensor connection, and the police filter connection.If these signals are present, the control logic of the electronic control unit detects that the agricultural fluid application system is being operated as intended with the police filter device. If at least one of these signals is missing, the control logic can detect that the agricultural fluid application system is not being operated with a police filter device. It is also possible that the signals at the respective connection are checked for plausibility and evaluated, which can also be used to detect devices simulating signals that do not correspond to the intended police filter device. If operation without a police filter device or with another device that is not intended is detected, one of the aforementioned measures can be initiated. In this case, in particular, an error is entered and / or the operation of the agricultural fluid application system is terminated or shut down.

[0018] According to one embodiment of the invention, the control filter device of the agricultural fluid application system is multifunctional in that it is also used to control or regulate the operation of the field spraying device. In this case, for example, the control of a valve of the field spraying device, in particular the pulse width modulation, can be adapted to the output pressure measured by the output pressure sensor of the control filter device. This embodiment is based on the knowledge that a pressure specified, for example, by a pump can deviate from the pressure at a fluid inlet of the field spraying device depending on the current operating state of the lines and filters, which can lead to a deviation of the application behavior of the field spraying device from the target application behavior. The output pressure sensor can therefore be used to detect the actual output pressure as close as possible to the field spraying device.The same applies if, alternatively or cumulatively, the operation of the field spraying device is controlled or regulated taking into account the flow measured by the flow meter of the police filter device.

[0019] It is fundamentally possible for the police filter device to have only one inlet connection and one outlet connection, so that all of the agricultural fluid fed to the police filter device is fed to the at least one field spraying device. In a particular proposal of the invention, the police filter device, in addition to the inlet connection and the outlet connection, also has a flushing outlet, which can be either a connection for a flushing line leading into the environment or a container, or a direct outlet into the environment. In this case, the police filter device has a branch via which the inlet connection is connected to both the outlet connection and the flushing outlet. If the flushing outlet is closed, the fluid can flow completely from the inlet connection to the outlet connection during normal operation.If, however, the flushing outlet is open, a partial flow of the agricultural fluid is used to flush the police filter unit, while the other partial flow of the agricultural fluid is directed to at least one field sprayer and thus applied to the agricultural area. In this case, any additional connection of the police filter unit to an additional flushing line is unnecessary.

[0020] Within the scope of the invention, a manually controlled valve can be arranged upstream of the flushing outlet. This valve can be a ball valve, for example. Alternatively or additionally, an electronically controlled valve can be arranged upstream of the flushing outlet. The electronically controlled valve also enables automatic control of the valve by the control logic of an electronic control device in order to automatically control or regulate the flushing operation.

[0021] Under certain circumstances, it may be desirable for the agricultural fluid to continue to be applied to an agricultural field via the at least one field spraying device with the remaining partial fluid flow during a flushing operation of the police filter device. Since the branching of the flushing flow changes the flow rate and / or pressure at the outlet connection of the police filter device and thus also at the at least one field spraying device, the application behavior from the at least one field spraying device may change in an undesirable manner. For one proposal of the invention, control logic is provided which, when the valve is moved into the open position, i.e. when the flushing operation is carried out, automatically adjusts the operation of the pump and / or the at least one field spraying device.In particular, this adaptation is carried out in such a way that the application behavior of the at least one field spraying device remains unchanged or a changeover to an emergency application behavior or a flushing operation application behavior, which deviates from the normal application behavior in a predetermined manner, takes place.

[0022] In principle, it is possible for the police filter device to be monitored not only on the basis of the inlet pressure sensor, the outlet pressure sensor, and / or the flow meter. A wide variety of other monitoring options can be used within the scope of the invention. For example, the extent of contaminant deposits on the police filter can be detected using an electrical, capacitive, inductive, or other deposit sensor. It is also possible for the deposits to be detected using an optical sensor on the police filter device and taken into account for monitoring. According to one proposal of the invention (alternatively or additionally), the police filter device has a viewing window. The viewing window is transparent. The viewing window allows the user to inspect the condition of the police filter of the police filter device.

[0023] As previously explained, it is also possible within the scope of the invention to detect whether the agricultural fluid application system is operated with a police filter device or a police filter unit. It is also possible within the scope of the invention to monitor whether a police filter is used in an existing police filter device or police filter unit. In this case, it is possible, for example, for the deposits of contaminants on an existing police filter to be detected by an increase in the pressure difference between the inlet pressure and the outlet pressure. If, on the other hand, a police filter device without a police filter is used, the throttling effect of the police filter can be omitted for one embodiment of the invention, which can lead to the pressure difference between the inlet pressure and the outlet pressure becoming smaller than a target value for a used, uncontaminated police filter.Based on such a detected pressure drop, it can be determined that the police filter device is not being operated as intended, i.e., without a police filter. In this case, different directions of changes in the pressure difference may arise, on the one hand, for the deposits of contaminants on the police filter and, on the other hand, for the operation of the police filter device without a police filter installed. Accordingly, it can also be determined if a different police filter, particularly one with different or coarser filter characteristics, is being used instead of a proper police filter. Finally, it is also possible that the pressure difference can be used to detect a defect in the police filter.

[0024] For a particular proposal of the invention, the flow path of the agricultural fluid in the police filter device and the police filter are designed such that, for an uncontaminated police filter arranged in the police filter device, a smaller pressure difference results between the inlet pressure and the outlet pressure than during improper operation, in which no police filter is arranged in the police filter device. For example, with the police filter arranged in the police filter device, the flows of the agricultural fluid can be directed in such a way that short flow paths result without throttling effects and turbulence. Without the conductive effect of a police filter, longer flow paths, increased throttling effects, and / or an increased degree of turbulence occur, which are responsible for a pressure increase when the police filter is omitted.In this case, both the deposition of contaminants on the police filter and the improper removal of the police filter lead to an increase in the pressure difference.

[0025] Within the scope of the invention, there are a variety of design options for the police filter device. According to one proposal, the police filter device has two housing parts (which themselves can be constructed as one or more parts).

[0026] A housing part then comprises an electronic control unit and / or a circuit board and / or at least one sensor. Furthermore, the housing part has an electrical connection, in particular for a CAN bus line, or an electrical connection cable, in particular a CAN bus line. The housing part, and thus the police filter device, can communicate with other electrical and electronic components of the agricultural fluid application system via the line or cable. For example, a connection can be made to another electronic control device and / or a controlling connection can be made to at least one field spraying device, the pump, or other electrically controlled components of the agricultural fluid application system. This housing part is then flanged to the other housing part.

[0027] The other housing section contains the police filter. Alternatively or cumulatively, the other housing section can contain the inlet connection, the purge connection, and / or the outlet connection.

[0028] For this embodiment, the two housing parts are preferably specifically adapted to the functionalities and requirements in that the first-mentioned housing part has the electrical and electronic components, while the second housing part has or forms the fluidic components such as the connections, the filter and the flow channels for the agricultural fluid.

[0029] Preferably, the sensors, for example, the input pressure sensor and the output pressure sensor, are mounted on the aforementioned circuit board and extend through a recess or a sensor channel into an input channel or output channel of the other housing part. Alternatively, it is possible for the input channel or output channel of the other housing part to be fluidically connected to a sensor surface of the respective sensor through a recess in the first-mentioned housing part.

[0030] Advantageous further developments of the invention emerge from the patent claims, the description and the drawings.

[0031] The advantages of features and combinations of several features mentioned in the description are merely exemplary and can be effective alternatively or cumulatively, without the advantages necessarily having to be achieved by embodiments according to the invention.

[0032] With regard to the disclosure content – ​​not the scope of protection – of the original application documents and the patent, the following applies: Further features can be found in the drawings – in particular the illustrated geometries and the relative dimensions of several components to one another, as well as their relative arrangement and operative connection. The combination of features of different embodiments of the invention or features of different patent claims is also possible, deviating from the chosen references of the patent claims, and is hereby encouraged. This also applies to features that are illustrated in separate drawings or mentioned in their description. These features can also be combined with features of different patent claims.Likewise, features listed in the patent claims may be omitted for further embodiments of the invention, but this does not apply to the independent patent claims of the granted patent.

[0033] The number of features mentioned in the claims and the description is to be understood as meaning that exactly this number or a greater number than the stated number is present, without the need for the explicit use of the adverb "at least." Thus, for example, if reference is made to one element, this is to be understood as meaning that exactly one element, two elements, or more elements are present. The features mentioned in the claims may be supplemented by further features or may be the only features present in the subject matter of the respective claim.

[0034] The reference signs contained in the patent claims do not represent a limitation of the scope of the subject-matter protected by the patent claims. They serve solely to make the patent claims easier to understand. BRIEF DESCRIPTION OF THE CHARACTERS

[0035] In the following, the invention is further explained and described with reference to a preferred embodiment shown in the figure. Fig. 1 shows a schematic of an agricultural fluid application system. Fig. 2 shows schematically in a longitudinal section a police filter unit that can be used in an agricultural fluid application system according to Fig. 1 . FIGURE DESCRIPTION

[0036] Fig. 1shows a schematic diagram of an agricultural fluid application system 1. The agricultural fluid application system 1 has an agricultural fluid tank 2 in which an agricultural fluid is stored. From the agricultural fluid tank 2, the agricultural fluid flows via a supply line 3 to a field sprayer assembly 4, which may have several field spraying devices 5a, 5b... that are held on a spray boom 6. The agricultural fluid supplied from the agricultural fluid tank 2 via the supply line 3 to the field sprayer assembly 4 is applied via the field sprayer assembly 4 (in particular onto arable land), wherein the entire supplied agricultural fluid or a partial flow thereof can be temporarily or permanently returned to the agricultural fluid tank 2 via a return line 7.

[0037] The agricultural fluid is conveyed by a conveying device 8, which is preferably a pump 10 driven by a motor 9. The conveying device 8 provides the agricultural fluid at the required pressure and flow rate.

[0038] Optionally, a pressure relief line 11 with a pressure relief valve 12 can branch off from the supply line 3. If the switching pressure of the pressure relief valve 12 is exceeded, the pressure relief valve 12 opens the pressure relief line 11, thereby establishing a connection between the supply line 3 and the agricultural fluid container 2 and preventing a pressure increase in the supply line 3 above the switching pressure specified by the pressure relief valve 12. It is possible, as shown, for the switching pressure of the pressure relief valve 12 to be adjusted electrically as needed by an electronic control device 27.

[0039] In the supply line 3 (behind the branch of the pressure relief line 11), two filters 13, 14 are arranged in series, which ensure the sufficient removal of contaminants from the agricultural fluid during normal operation. The filters 13, 14 can have different filter characteristics, whereby, for example, the upstream filter 13 can have a coarser filter characteristic than the downstream filter 14.

[0040] Between the filters 13, 14 and the field sprayer assembly 4, a police filter device 15 is arranged, which is preferably designed as a police filter unit 16.

[0041] In the return line 7, a valve 17 is preferably arranged, which can be actuated by a motor 18 controlled by an electronic control device 27, for example in order to provide a stepped or continuously variable passage cross-section and / or to bring about an opening and closing position.

[0042] The police filter device 15 has a police filter 19, which ensures the safety function mentioned above, while optionally, by means of the police filter 19, a final cleaning function can also be provided in addition to the effect of the filters 13, 14 even during normal operation.

[0043] The police filter device 15 has an inlet pressure sensor 20 which detects the pressure at the inlet of the police filter device 15 and upstream of the police filter 19.

[0044] Furthermore, the police filter device 15 has an outlet pressure sensor 21 which detects the pressure on the outlet side of the police filter device 15 and downstream of the police filter 19.

[0045] The police filter device 15 further comprises a flow meter 22, which is arranged upstream of the police filter 19 here, but can also be arranged downstream thereof.

[0046] The signals from the inlet pressure sensor 20, the outlet pressure sensor 21, and the flow meter 22 are transmitted to an electronic control device 27, where, taking into account the differential pressure between the signals from the inlet pressure sensor 20 and the outlet pressure sensor 21, the pressure difference is determined. This pressure difference is then used as the basis for monitoring and, in particular, to determine whether a suitable fluid is being used and / or whether the filters 13, 14 are functioning properly. The signal from the flow meter 22 can be used additionally for this purpose, particularly taking into account a model or a characteristic map.

[0047] The invention also encompasses other embodiments of the agricultural fluid application system. To name just a few non-limiting examples, any number of filters can be arranged upstream of the control filter device 15, for example, just one filter or more than two filters. It is also possible for the supply line 3 to branch into supply line sub-lines 3a, 3b..., each of which has a subgroup of field spraying devices that can be separately controlled for section control. In this case, the control filter device 15 can be arranged in the supply line 3 upstream of the branching to the supply line sub-lines 3a, 3b..., or a control filter device 15 can be arranged in a supply line sub-line 3a, or a control filter device 15 can be arranged in each of several supply line sub-lines 3a, 3b.

[0048] In Fig. 1A further optional design feature of the agricultural fluid application system 1 is shown: Here, the filters 13, 14 are each connected to a flushing line 23, 24, which enables flushing of the filters 13, 14 when contaminants have accumulated in the filters 13, 14. For the illustrated embodiment, the flushing line 23, 24 branch off from the pressure relief valve 11 downstream of the pressure relief valve 12. Shut-off valves 25, 26 are arranged in the flushing line 23, 24, which are opened for flushing operation. For the illustrated embodiment, the shut-off valves 25, 26 are designed as manually operated valves.However, it is also entirely possible for the shut-off valves 25, 26 to be opened, partially closed and / or blocked automatically by means of an electronic control unit, whereby this can also be done on the basis of the monitoring by the police filter device 15, in particular with a flushing of the filters 13, 14 triggered automatically by the control device 27, if it is detected as a result of the monitoring by the police filter device 15 that at least one filter 13, 14 is blocked.

[0049] With regard to further design options for the agricultural fluid application system 1 (and here in particular the fluid circuit with the supply line 3 and the return line 7; the field sprayer assembly 4 with field spraying devices 5a, 5b... ; the control measures for controlling the fluidic components, in particular the valves of the field spraying devices 5a, 5b, ... and the different operating states; and the controls and regulations, reference is made by way of example to the documents EP 4 080 315 A1, EP 3 646 725 A1, EP 3 837 060 A1, EP 2 979 765 A1, EP 2511 783 A1 and EP 2 227 949 A1 of the applicant.

[0050] If an electronic control unit or control device is mentioned in the present application text, it may be a single central control unit to which the signals from the police filter device 15 are fed and which is responsible for the electronic control or regulation of the components (in particular the motor 9 of the pump 10, the pressure relief valve 12, the valves of the field spraying devices 5a, 5b, ..., and the motor 18 of the valve 17). However, it is also possible that the processing of signals and the control or regulation of the aforementioned components are carried out by individual electronic control devices or units, which may then be independent of one another or networked with one another.In particular, it is possible for the police filter unit 16 to have an integrated electronic control unit which outputs the result of the monitoring as a signal and transmits it to another electronic control unit which is then responsible for controlling the other components of the agricultural fluid application system 1.

[0051] In Fig. 1 By way of example, a single electronic control device 27 is shown, which is connected to the motor 9, the pressure relief valve 12, the inlet pressure sensor 20, the outlet pressure sensor 21, the flow meter 22, the field spraying devices 5a, 5b, ... and the motor 18 for signal transmission and control or regulation via lines 28 to 34.

[0052] In the event that the police filter device 15 is designed as a police filter unit 16, the police filter unit 16 can be connected via a line 35 to a police filter connection 36 of the electronic control device 27. In contrast, the signal of the inlet pressure sensor 20 is transmitted via line 30 to an inlet pressure sensor connection 37 of the control device 27, the signal of the outlet pressure sensor 21 is transmitted via line 31 to an outlet pressure sensor connection 38 of the control device 27, and the signal of the flow meter 22 is transmitted via line 32 to a flow meter connection 39 of the control device 27.

[0053] Fig. 2 shows an exemplary embodiment of a police filter unit 16, which can be used in the agricultural fluid application system 1 according to Fig. 1The police filter unit 16 has a housing part 40, which has or forms the fluidic components. The housing part 40 has an inlet connection 41, to which the agricultural fluid is fed from the filters 13, 14. The housing part 40 further has an outlet connection 42, from which the agricultural fluid reaches the field sprayer assembly 4. Furthermore, the housing part 40 has a flushing outlet 43, through which a partial flow of the agricultural fluid can exit directly onto the agricultural area during flushing operation or enter a flushing container. A valve 44 is arranged upstream of the flushing outlet 43. For the illustrated embodiment, the valve 44 is designed as a ball valve 45, although any other manually operated valve or an electrically controlled valve can also be used.

[0054] The inlet connection 41 and the outlet connection 42 open into an interior space 46 of the housing part 40. A pressure filter 47 is arranged in the interior space 46. The pressure filter 47 separates (with the filtering effect) the inlet connection 41 from the outlet connection 42, without allowing a bypass of the pressure filter 47 for the agricultural fluid. For the illustrated embodiment, the interior space 46 is cylindrical, optionally with a slightly conical outer surface. The pressure filter 47 is sleeve-shaped or hollow-cylindrical and arranged concentrically to the interior space 46. A hollow-cylindrical annular space, which is delimited radially inward by the pressure filter 47 and radially outward by a wall of the housing part 40, enables the entire cylindrical outer surface of the pressure filter 47 to be exposed to a partial fluid flow 62 of the agricultural fluid provided via the inlet connection 41.After the fluid partial flow 62 passes through the police filter 47, the flow continues to the outlet connection 42.

[0055] For the illustrated embodiment (without this being shown in the drawing) Fig. 2 shown), the housing part 40 is formed in two parts with an upper part 48 and a lower part 49. The upper part 48 forms the inlet connection 41 and the outlet connection 42. The lower part 49 delimits the interior space 46 accommodating the police filter 47 in the radial direction and downwards. The lower part 49 forms the flushing outlet 43 and has the valve 44. The police filter 47 is clamped in the direction of its longitudinal axis between the upper part 48 and the lower part 49 (with the contacting end faces sealed) and is thus fixed.

[0056] Another housing part 50 is flanged to the housing part 40. The other housing part 50 comprises, in particular, the electrical and electronic components of the police filter unit 16. The housing part 50 contains a circuit board 51, which carries the inlet pressure sensor 20 and the outlet pressure sensor 21 or is connected to them. Also located on the circuit board 51 is an electronic control device, which can communicate via a line 35 with another or the central control unit 27. The housing part 50 further comprises an electrical connection 52, to which an electrical connection cable 53 is connected, which connects the line 35 in Fig. 1 can form. The circuit board 51 and / or the electronic control unit of the police filter unit 16 communicates with other components of the agricultural fluid application system 1 via the electrical connection 52 and the electrical connection cable 53.

[0057] For the illustrated embodiment, an inlet channel 54, which connects to the inlet connection 41 and is arranged upstream of the police filter 47, has a recess 64 leading into the housing part 50, which is closed by the inlet pressure sensor 20 with its sensor surface.

[0058] Correspondingly, the housing part 40 has an outlet channel 55, which is located downstream of the pressure filter 47 and upstream of the outlet connection 42. The outlet channel 55 has a recess 56 that opens into the housing part 50 and is closed by the outlet pressure sensor 21 in the region of its sensor surface.

[0059] In this way, the input pressure sensor 20 can sense the input pressure in the input channel 54 and the output pressure sensor 21 can sense the output pressure in the output channel 55.

[0060] It is possible that the upper part 48 and the lower part 49 of the housing part 50 are connected by means of a screw connection 57, which Fig. 2 shown only schematically with a thickened portion, are screwed together. If the lower part 49 is unscrewed from the upper part 48, the police filter 47 can be replaced. By tightening the screw connection 57, the police filter 47 can be clamped between the upper part 48 and the lower part 49.

[0061] It is possible that the lower part 49 has a viewing window 58 through which the user can inspect the condition of the police filter 47 and, depending on the degree of contamination, replace it. It is possible that the viewing window 58 represents only a portion of the housing part 40 or the lower part 49, which are otherwise made of a non-transparent material. However, it is also possible that the entire lower part 49 is made of a transparent material.

[0062] For the illustrated embodiment, a baffle, deflection, or labyrinth plate 59 is arranged in the inlet channel 54, inclined or approximately vertically to the flow direction of the agricultural fluid. This plate is formed here by the upper part 48 and at the end region of which the police filter 47 can be supported. It is possible that the design of the guide surfaces for the agricultural fluid and in particular a guide surface of the baffle, deflection, or labyrinth plate 59 is structurally predetermined in such a way that, with an uncontaminated police filter 47, a smaller differential pressure results between the inlet pressure and the outlet pressure, while without the police filter 47, a larger pressure difference results, for example, as a result of turbulence then forming on the baffle, deflection, or labyrinth plate 59. The baffle, deflection, or labyrinth plate 59 is in Fig. 2merely simplified and shown schematically. With the desired goal of generating a pressure increase without using the pressure filter 47, the skilled person can select other shapes for the baffle, deflection, or labyrinth plate 59 and other flow-guiding surfaces of the housing part 40.

[0063] If the valve 44 is opened, a fluid flow 60, which is supplied to the police filter unit 16 via the inlet connection 41, is divided via a branch 61 into a fluid partial flow 62, which passes through the police filter 47 to the outlet connection 42, and a fluid partial flow 63, which passes to the flushing outlet 43.

[0064] If the control filter unit 16 or the evaluation of its signals indicates that the filters 13, 14 are not functioning properly, the operation of the agricultural fluid application system 1 may be interrupted. However, it is also possible that further operation may then occur. During further operation, the agricultural fluid can be applied from the field sprayers 5 as unchanged as possible, if necessary by changing the delivery rate of the pump 10 and / or the operation of the at least one field sprayer 5. Filtering by the control filter 47 may then occur or begin.However, it is also possible that a permanent or time-limited emergency operation takes place in which (using a filter effect of the police filter 47) a modified application of the agricultural fluid by the field spraying device takes place, for example with a reduced application flow, a modified spray cone or a modified droplet size, wherein the operating parameters of the pump 10 and / or the field spraying devices 5 can then remain unchanged or can be specifically changed for the emergency operation by an electronic control device. LIST OF REFERENCE SYMBOLS

[0065] 1Agricultural fluid application system 2Agricultural fluid tank 3Supply line 4Field sprayer assembly 5Field sprayer 6Spray boom 7Return line 8Feeder 9Motor 10Pump 11Pressure relief line 12Pressure relief valve 13Filter 14Filter 15Police filter device 16Police filter unit 17Valve 18Motor 19Police filter 20Inlet pressure sensor 21Outlet pressure sensor 22Flow meter 23Flushing line 24Flushing line 25Shut-off valve 26Shut-off valve 27Electronic control device 28Line 29Line 30Line 31Line 32Line 33Line 34Line 35Line 36Police filter connection 37Inlet pressure sensor connection 38Outlet pressure sensor connection 39Flowmeter connection 40Housing part 41Inlet connection 42Outlet connection 43Flush outlet 44Valve 45Ball valve 46Interior 47Police filter 48Upper part 49Lower part 50Housing part 51PCB 52Electrical connection 53Electrical connection cable 54Inlet channel 55Outlet channel 56Recess57Screw connection 58Viewing window 59Baffle, deflection or labyrinth plate 60Fluid flow 61Branching 62Partial fluid flow 63Partial fluid flow 64Recess

Claims

1. Agricultural fluid discharge system (1) comprising an agricultural fluid reservoir (2) which is connected via a conveying device (8) and at least one filter (13, 14) and / or separator to at least one field spraying device (5) by which an agricultural fluid can be discharged on an agricultural area, and with an electronic control device (27) which controls (open-loop control or closed-loop control) the operation of the conveying device (8) and / or the at least one field spraying device (5), characterised in that a control filter device (15) is arranged between the filter (13, 14) and / or separator and the at least one field spraying device (5).

2. Agricultural fluid discharge system (1) of claim 1, characterised in that the control filter device (15) comprises a) an inlet pressure sensor (20) and / or an outlet pressure sensor (21) and / or b) a flowmeter (22).

3. Agricultural fluid discharge system (1) of claim 1, characterised in that the control filter device (15) comprises an inlet pressure sensor (20) and an outlet pressure sensor (21) and the or an electronic control device (27) provides a control or monitoring on the basis of a pressure difference between the inlet pressure sensed by the inlet pressure sensor (20) and the outlet pressure sensed by the outlet pressure sensor (21).

4. Agricultural fluid discharge system (1) of claim 1, characterised in that the control filter device (15) comprises an inlet pressure sensor (20), an outlet pressure sensor (21) and a flowmeter (22) and the or an electronic control device (27) provides the control or monitoring on the basis of a) a pressure difference between the inlet pressure sensed by the inlet pressure sensor (20) and the inlet pressure sensed by the outlet pressure sensor (21) as well as b) a model of a dependency of the pressure difference and the flow sensed by the flowmeter (22).

5. Agricultural fluid discharge system (1) of one of the preceding claims, characterised in that control logic is provided which a) actuates a signalling device and / or b) generates an error entry and / or c) controls (open-loop control or closed-loop control) the operation of a pump (10) and / or of at least one field spraying device (5) and / or d) controls (open-loop control or closed-loop control) an operation position of a valve (17) in a supply line branch and / or a return line branch and / or e) controls (open-loop control or closed-loop control) an automatic flushing of the control filter device (15) dependent on the result of the control or monitoring.

6. Agricultural fluid discharge system (1) of one of claims 2 to 5, characterised in that control logic is provided which on the basis of a) a signal at an inlet pressure sensor port (37) and / or b) a signal at an outlet pressure sensor port (38) and / or c) a signal at a control filter port (36) detects if the agricultural fluid discharge system (1) is operated with a control filter device (15).

7. Agricultural fluid discharge system (1) of one of claims 2 to 6, characterised in that control logic is provided which under consideration of a) the outlet pressure sensed by the outlet pressure sensor (21) and / or b) the flow sensed by the flowmeter (22) controls (open-loop control or closed-loop control) the operation of the field spraying device (5).

8. Agricultural fluid discharge system (1) of one of the preceding claims, characterised in that the control filter device (15) comprises a branching (61) by which the inlet port (41) of the control filter device (15) is connected both to an outlet port (42) connected to the field spraying device (5) as well as to a flushing outlet (43).

9. Agricultural fluid discharge system (1) of claim 8, characterised in that an electronically and / or manually controlled valve (44) is arranged upstream from the flushing outlet (43).

10. Agricultural fluid discharge system (1) of claim 9, characterised in that control logic is provided which (in particular dependent on the result of the monitoring) transfers the valve (44) being arranged upstream from the flushing outlet (43) into an open position.

11. Agricultural fluid discharge system (1) of claim 10, characterised in that control logic is provided which adjusts the operation of the pump (10) and / or of the at least one field spraying device (5) together with the transfer of the valve (44) into the open position.

12. Agricultural fluid discharge system (1) of one of the preceding claims, characterised in that the control filter device (15) comprises an inspection window (58) by which the user is able to inspect a state of the control filter (47) of the control filter device (15).

13. Agricultural fluid discharge system (1) of one of the preceding claims, characterised in that the streaming path of the agricultural fluid in the control filter device (15) and the control filter (47) is designed such that in the case that the control filter (47) arranged in the control filter device (15) is not impurified there is a smaller pressure difference between the inlet pressure sensed by an or the inlet pressure sensor (20) and the outlet pressure sensed by an or the outlet pressure sensor (21) than in the case that there is no control filter (47) arranged in the control filter device (15).

14. Agricultural fluid discharge system (1) of one of the preceding claims, characterised in that the control filter device (15) comprises a housing part (50) which a) comprises an electronic control unit, a printed circuit board (51) and / or at least one sensor, b) comprises an electric port (52), in particular for a CAN-BUS-line, or an electric connection cable (53), in particular a CAN-BUS-line, and c) is flanged to a housing part (50) which contains the control filter (47) and / or comprises the inlet port (41), the flushing port (43) and / or the outlet port (42).