AGRICULTURAL SPRAYER AND SPRAYING DEVICE FOR AN AGRICULTURAL SPRAYER

Description

[0001] The invention relates to a spraying device for an agricultural field sprayer for the metered application of spray liquid, preferably on agricultural land. The spraying device comprises a spray boom with lateral extension arms. The invention further relates to an agricultural field sprayer with such a spraying device.

[0002] Document EP 1 066 757 A1 discloses a section line of a spray line of an agricultural field sprayer with branch lines arranged at equal intervals within the section line, to which nozzles or drag hoses are connected and which is fed via a supply line. The cross-section of the section line decreases continuously and / or gradually from the feed point toward the side facing away from the feed point.

[0003] Document US 2018 / 228079 A1 discloses a device for applying a liquid to the soil, comprising a foldable distributor bar for receiving and dispensing a liquid stream. The foldable distributor bar consists of a plurality of stainless steel sections and has a decreasing inner diameter from an inlet of the distributor bar to a distal end of the distributor bar.

[0004] Agricultural field sprayers are used for spreading or applying liquid active substances, such as crop protection agents and / or fertilizers. Such field sprayers, with a spray boom oriented transversely to the direction of travel and moving over a crop, are available in various designs.

[0005] The aim of such field sprayers is to apply a defined volume of spray liquid, e.g. crop protection and / or fertilizer, evenly and with a definable intensity to a crop. In order to apply the spray liquid over a large area of ​​the cultivated land, the spray booms of such field sprayers have lateral, foldable booms with a large working width, sometimes more than twenty meters. For transport, such wide spray booms are folded and collapsed. When unfolded, the booms are arranged transversely to the direction of travel. The spray boom is equipped with spaced-apart application elements, e.g. spray nozzles, for the metered application of the spray liquid. The application elements create a spray cone directed towards the ground or the crop for the desired distribution of the spray liquid.

[0006] With the current practice of using ready-mixed spray liquid in a large storage container, the consumption of plant protection products is high in the case of heterogeneous pest occurrence or growth stages if the damage threshold is not reached in the partial area or the growth stage is sufficient and therefore no application is indicated.

[0007] In order to save on passes and to be able to quickly change the active ingredient composition according to the existing requirements on the field, so-called "direct feed systems" are known from the state of the art, in which an active ingredient dissolved in a liquid, e.g., a plant protection product to be applied, can be added to a carrier liquid or a pre-mixed spray liquid via direct feed as needed.

[0008] However, the field sprayers known from practice here have the disadvantage that central dosing via direct feed leads to significant delays if the feed point is too far from the spray nozzles and the fluid paths from the feed point to the individual spray nozzles also vary significantly. This results in the so-called butterfly effect, since the spray liquid mixture generated via direct feed does not reach all spray nozzles immediately, but rather builds up over the entire working width with a delay, resulting in at least temporarily uneven distribution of the active ingredient.

[0009] In order to enable site-specific application, field sprayers are also known in practice that have several independent fluid circuits for different active ingredients. Depending on the desired site-specific treatment, the fluid circuits or the application nozzles assigned to them can be switched on or off accordingly. The disadvantage of such approaches is that, depending on the number of different active ingredients, separate fluid circuits must be installed on the field sprayer, which in turn is cost-intensive and requires a lot of space. It is also possible that the spray cones of the at least two adjacent application nozzles influence each other, which in turn impairs the distribution quality.

[0010] Alternative approaches, in which the direct injection or dosing of a pesticide occurs immediately in or at each spray nozzle, avoid the need for additional spray nozzles, but have the disadvantage of requiring additional valve technology and a mixing chamber at each spray nozzle, which is costly. Furthermore, the limited space in the spray nozzle area makes homogeneous mixing difficult.

[0011] It is therefore an object of the invention to provide an improved technique for dispensing spray liquid using a spray boom, by means of which the disadvantages of conventional techniques can be avoided. The object of the invention is, in particular, to provide a technique for dispensing spray liquid using a spray boom, by means of which improved dosing of the spray liquid via direct feed is enabled.

[0012] The problem is solved by the features of the independent claim. Advantageous further developments are specified in the dependent claims and the description.

[0013] According to a general aspect of the invention, a spraying device for an agricultural field sprayer is provided for the metered application of spray liquid, preferably on agricultural land. The spraying device comprises a line for spray liquid, hereinafter referred to as the supply line for spray liquid, which has a section extending in the longitudinal direction of the spray boom. This section can preferably be a section guided along the spray boom. Such a supply line serves, in a manner known per se, to supply spray liquid to the application elements arranged at regular intervals in the longitudinal direction of the spray boom or the booms.For this purpose, the aforementioned section of the supply line has several branching points distributed longitudinally, at each of which spray liquid can be branched off and / or is branched off to supply a portion of the application elements with spray liquid. The liquid flow within the supply line along the section is thus gradually reduced when spray liquid is branched off from the section of the supply line at the branching points.

[0014] The longitudinal direction of the boom and spray boom refers to the direction in which the boom extends and the spacing of the application elements, such as the spray nozzles or nozzle bars, along the boom. The working width of the spray boom is determined by the length of the spray boom along its longitudinal direction when extended. The vertical direction of the boom refers to the direction perpendicular to the longitudinal direction of the boom and perpendicular to the direction of travel of the field sprayer.

[0015] According to the invention, the spraying device is characterized in that the section of the supply line extending in the longitudinal direction of the spray boom has an inner diameter that decreases in the direction of flow. This offers the advantage that a pressure loss caused by the branching of spray liquid at the branching points and thus a reduced flow velocity along the section can be counteracted. A particular advantage is that it can reduce the delay times until an active ingredient metered into a carrier liquid or a pre-mixed spray liquid via direct feed reaches the application elements via the supply line, in particular when switching the direct feed on and off. Accordingly, the supply line according to the invention offers particular advantages for field sprayers with a direct feed system downstream of the supply line.

[0016] In a particularly preferred embodiment, the supply line is designed such that the inner diameter of the section of the supply line extending in the longitudinal direction of the spray boom gradually decreases. A gradual, i.e., discrete, reduction of the inner diameter is particularly advantageous because, accordingly, line sections with standardized inner diameters or nominal diameters can be used.

[0017] In a further embodiment, the section with decreasing inner diameter has at least three or at least four subsections with different inner diameters.

[0018] With at least three such sections, the gradual reduction in fluid flow within the supply line caused by the multiple branching points can be particularly effectively counteracted. In a further embodiment, the inner diameter of the section is gradually reduced by 1 mm and / or 2 mm.

[0019] In an alternative embodiment, the inner diameter of the section is reduced incrementally by 1 nominal diameter (DN) (nominal diameter according to DIN EN ISO 6708, French: Diamètre Nominal, Diameter Nominal) and / or by 2 nominal diameters (DN). For example, the section could have sections with nominal diameters of DN8, DN6, and DN4, which would correspond to a gradual reduction of the inner diameter by 2 nominal diameters each. Accordingly, pipe sections with standardized inner diameters or nominal diameters can be advantageously used.

[0020] It has already been established above that the section of the supply line with decreasing inner diameter has several branching points for branches, each supplying a portion of the application elements with spray liquid. The decreasing inner diameter can be defined such that the section between the first and last branching point has several subsections whose inner diameters differ, in particular decreasing in the direction of flow. Furthermore, it is possible for these subsections to be 1 and / or 2 mm smaller than the upstream subsection, or to be 1 nominal diameter (DN) and / or 2 nominal diameters (DN) smaller than the upstream subsection.

[0021] Alternatively or additionally, the decreasing inner diameter can be determined such that at least one of the following conditions a) to c) is met: a) a flow velocity of the spray liquid at at least one branching point downstream of a first branching point is at least as high as at the first branching point, b) a flow velocity of the spray liquid does not decrease continuously in the section; and c) a flow velocity of the spray liquid fluctuates between the first and last branching point by no more than 2 m / s, more preferably by no more than 1 m / s.

[0022] By appropriately determining the inner diameter, a high flow velocity can be maintained. The appropriate determination of the change in the inner diameter to meet the aforementioned conditions can be determined by appropriate experimentation with different inner diameters along the section, for example, by appropriate tests in which the flow velocity along the section is determined for different designs with the inner diameter decreasing in the flow direction.

[0023] The supply line may be designed as a stub line, which does not fall within the scope of protection of the claims.

[0024] According to the invention, the supply line is designed as a ring line, preferably a ring line through which an active ingredient, metered into a carrier liquid or a pre-mixed spray liquid by direct feed, is conveyed to the application elements. The section of the ring line with a decreasing inner diameter then shortens the delay time, particularly during start-up, i.e., at the start of the spraying process, or when changing the spray liquid or its mixture during direct feed.

[0025] In a particularly advantageous embodiment, the supply line, namely the supply line designed as a ring line, is connected to a mixing chamber for mixing two spray liquids, preferably in such a way that spray liquid mixed in the mixing chamber can be fed for further transport towards the application elements of the ring line. The spray liquid can thus be circulated in the ring line in order to have the correct / desired liquid, i.e. the liquid with the correct / desired concentration, available at the required position on the spray boom as quickly as possible, i.e. without any delay. It is particularly advantageous if the mixing chamber is a mixing chamber of a direct feed system of the spraying device.Such a mixing chamber is also referred to below as the main mixing chamber to better distinguish it from other optionally available mixing chambers, which can be arranged downstream of the main mixing chamber and which can be supplied with spray liquid mixed in the main mixing chamber via the supply line.

[0026] A pump for conveying the spray liquid or generating a delivery pressure can be installed in the supply line, which is designed as a ring line. Furthermore, the ring line can be designed to convey the spray liquid back to the main mixing chamber after it has been conveyed through the section with the decreasing inner diameter. A throttle valve can be installed in the ring line after the section with the decreasing inner diameter.

[0027] It has already been established above that the supply line according to the invention with decreasing inner diameter is particularly advantageous in combination with a direct feed system.

[0028] According to a further advantageous development of the aforementioned embodiment with the main mixing chamber, the spraying device can have several dosing or supply systems for implementing a direct feed system, from which spray liquid can be provided, each with a storage container for spray liquid and means for providing the spray liquid as needed from the respective storage container, preferably in a metered manner. These several dosing or supply systems are described below. For better differentiation, the terms "first," "second," "third," etc. are used, for example, to better distinguish the first dosing system and its spray liquid (first spray liquid) from another, e.g., third dosing system and its spray liquid (third spray liquid).

[0029] The spraying device can accordingly comprise a first dosing system with a first storage container for a first spray liquid and a first dosing device. The first storage container can be the main tank of the spraying device or of a field sprayer, i.e. the tank that contains the main mixture. The main mixture is understood to be the usually already mixed spray liquid that is to be used for the most part by the spraying device or the field sprayer in an upcoming spraying process and / or that is stored in the largest spray liquid storage container of the field sprayer. However, the first spray liquid can also be clear water or another carrier liquid. The first dosing device is designed to provide the first spray liquid in doses from the first storage container.The first dosing device may comprise a flow meter and a pressure generating unit, preferably a pump.

[0030] The spray device can further comprise a second dosing or supply system, with a second reservoir for a second spray liquid, for example clear water or another carrier liquid, and a second dosing or fluid supply device. This second dosing or supply system does not necessarily serve to provide a precise or precisely dosed amount of spray liquid, but could also function as a supply tank from which the second spray liquid can be provided as needed, without, for example, a dosing valve being provided for precise dosing. Therefore, the term dosing or supply system or dosing or fluid supply device was chosen here to clarify this aspect. The second dosing or fluid supply device can comprise a flow meter, a check valve, and a pressure generating unit, preferably a pump.The second dosing or supply device may not include a dosing valve. The second storage container may be a water tank.

[0031] The spray device can further comprise a third dosing system, having at least one third dosing device and at least one third storage container and / or at least one container receptacle for releasably holding a third storage container for at least a third spray liquid or active ingredient. The third storage container is preferably a canister and / or the container receptacle is preferably a holder for such a canister, which can be held therein in an exchangeable manner. The third spray liquid or active ingredient can be a plant protection agent, preferably in concentrated form. The plant protection agent can be a growth regulator, fungicide, insecticide, pesticide and / or the like in liquid form. Also conceivable is a granulate that can be or is dissolved in liquid.The volume of the third storage container is preferably smaller, usually significantly smaller, than the volume of the first and / or second storage container.

[0032] Several such third container receptacles and / or third storage containers with a corresponding third dosing device can also be provided as part of the third dosing system, for example, to carry different third spray liquids, e.g., different crop protection agents, which can be mixed in as needed. The at least one third dosing device can each comprise a dosing valve, a flow meter, and a pressure generating unit, preferably a pump.

[0033] The second spray liquid can be supplied to the main mixing chamber via the second dosing or fluid supply device, and the at least one third spray liquid can be supplied via the at least one third dosing device. The spraying device further comprises a control device configured to control and / or regulate the first dosing system, the second dosing or supply system, the third supply system, and the dispensing elements for spraying and / or finely distributing the spray liquid.

[0034] With such a dosing or supply system, a third spray liquid provided by the third dosing system, e.g. an active ingredient in concentrated form, can be mixed and / or pre-diluted with spray liquid from the second dosing or supply system in the main mixing chamber and supplied to the application elements instead of the spray liquid of the first dosing system or in addition thereto.

[0035] For example, the control device can be configured to control the second dosing or fluid supply device and the at least one third dosing device depending on a target mixing ratio of the second and third spray liquids such that the second and third spray liquids are supplied to the main mixing chamber at the input side in the target mixing ratio. The target mixing ratio can be determined depending on which third spray liquid is currently to be mixed, so that, for example, different target mixing ratios can be determined for different crop protection agents. The target mixing ratio can optionally be determined by user input or automatically by reading it via a data interface.The third spray liquid can be pre-diluted according to the target mixing ratio and conveyed via the supply line with decreasing inner diameter with slight delay towards the application elements.

[0036] In a further advantageous development, the spray boom, and preferably each of the booms, is divided into several subsections. A plurality of dispensing elements for spraying and / or finely distributing the spray liquid are arranged at each subsection, and each dispensing element is assigned to precisely one subsection. The spraying device further comprises several mixing chambers, with each subsection being assigned one of the mixing chambers, which is arranged upstream of the dispensing elements assigned to the respective subsection. These mixing chambers are hereinafter referred to as first mixing chambers to better distinguish them from the previously described main mixing chamber, which is arranged upstream of these first mixing chambers.

[0037] It has already been established above that the section of the supply line with decreasing inner diameter has several branch points for branches to supply a portion of the application elements with spray liquid. Here, the first mixing chambers are fluidically connected on the inlet side to one of the branches of the supply line (hereinafter also referred to as the second supply line or second ring line).

[0038] The first mixing chambers are fluidically connected on the inlet side to another supply line, to which the first spray liquid can be fed via the first dosing device. This supply line, fed by the first dosing system, is hereinafter referred to as the first supply line. It can be designed, for example, as a ring line, hereinafter referred to as the first ring line, or as a branch line.

[0039] The supply line or ring line fed via the main mixing chamber, which has the section with a decreasing inner diameter, is also referred to below as the second supply line or second ring line to better distinguish it from the first supply line or first ring line. This second supply line is fed with spray fluid from the second dosing or supply system and / or third dosing system via the main mixing chamber. The branch points of the second supply line are fluidically connected to the first mixing chambers via the branches.

[0040] This division into subsections, each of which is assigned a mixing chamber and a group of application elements supplied by it, offers the advantage, in combination with the three dosing or supply systems and the second ring line, of enabling area-specific application via direct feed to smaller areas, while simultaneously reducing delay times and improving the uniform application of the active ingredient, especially during on / off operations and changes in the spray liquid or its mixture. The solution is also advantageous in terms of the required installation space and the costs of the required fluid technology.

[0041] In an advantageous further variant of this embodiment, fourth dosing devices are arranged in each of the branches for controlling and / or regulating a quantity of spray liquid supplied to the first mixing chambers from the second supply line. This offers the advantage that the quantity of spray liquid supplied from the second ring line or from the main mixing chamber to a specific first mixing chamber can be precisely adjusted, and thus the quantity of active ingredient fed in via the second inlet of the respective first mixing chamber. This further improves precise, area-specific application of a desired active ingredient concentration. The fourth dosing device is arranged, for example, in a branch that connects the second supply line to the respective mixing chamber. The fourth dosing devices can each comprise a flow meter and a dosing valve.

[0042] The control device can be configured to control and / or regulate the fourth metering devices, preferably their metering valves, depending on a variable that indicates a measure of a target application rate of second and / or third spray liquid to be dispensed by the application elements of the section supplied by the respective fourth metering device. This enables precise, area-specific direct injection.

[0043] In one embodiment, the control device can be configured to selectively supply a mixture of at least two of the spray liquids in a definable mixing ratio or only one of the spray liquids to the dispensing elements or dispensing elements of selected subsections by controlling the first dosing device, the second dosing or fluid supply device, the at least one third dosing device, and / or the fourth dosing device, preferably by supplying these spray liquids to the first mixing chambers or a subselection thereof in the definable mixing ratio. Accordingly, the mixing ratio for the subsections can be individually changed.Alternatively or additionally, the control device for producing a mixture of the first spray liquid with the second and / or at least one third spray liquid can be designed to control the first dosing system and the second dosing or supply system and / or the third dosing system in such a way that all of the first mixing chambers or a subselection thereof are supplied with both the first spray liquid and the second and / or third spray liquid in the definable quantity ratio.

[0044] It is also optionally possible for an additional agitator to be provided in the third storage tank, for example to prevent deposits of the respective agent in the storage tank. Cleaning of the spray system or the dosing systems can be carried out in a manner known from the prior art. Alternatively or additionally, it can be provided that the third storage tank can be optionally fed with clear water for cleaning purposes via an additional line, e.g., a flushing line, and a valve and / or pump associated with this line, for example, with clear water from the first dosing system and / or the second dosing or supply system.

[0045] Further advantageous embodiments relate to the design of the optional first mixing chambers and the design of the fluidic connection between the first mixing chambers and the respectively associated dispensing elements.

[0046] Further advantageous embodiments relate to the design of the first mixing chambers and the configuration of the fluidic connection between the first mixing chambers and the respectively associated dispensing elements.

[0047] The first mixing chamber can have a plurality of distributor outlets on the output side, wherein the dispensing elements arranged downstream of the respective first mixing chamber are each connected to one of the distributor outlets via a dispensing line. Alternatively, a fluid distributor for dividing spray liquid into a plurality of partial streams can be arranged downstream of an outlet of the first mixing chamber, comprising a plurality of distributor outlets for the partial streams, wherein the dispensing elements arranged downstream of the respective first mixing chamber are each connected to one of the distributor outlets of the fluid distributor via a dispensing line.

[0048] In other words, in such an embodiment, each of the subsections is provided with at least one device for mixing at least two spray liquids and for distributing the mixed spray liquids into a plurality of partial streams. The device thus has two functions: mixing the supplied spray liquids and subsequently distributing, which can also be referred to as dividing or branching, the mixed spray liquid into a plurality of partial streams, which are discharged via the distributor outlets in the form of a plurality of hydraulically parallel partial streams. For this purpose, this device comprises the mixing chamber and, downstream of the mixing chamber, the fluid distributor as functional components. The mixing chamber and the fluid distributor can be designed as a structural unit and thus as a combined mixing chamber-fluid distributor unit or as a mixing chamber with an integrated fluid distributor function, or as two separate components.Depending on the design variant, the term "distributor outlet" can refer to the distributor outlet of the mixing chamber with integrated fluid distributor or to the distributor outlet of the fluid distributor. The mixing chamber and / or the fluid distributor are preferably arranged on a boom of the spray boom.

[0049] Dividing the spray liquids mixed in the first mixing chambers into several partial streams, with one of the partial streams of mixed spray liquid being fed to the application elements via one of the distributor outlets, offers several advantages.

[0050] Firstly, the time delay until a mixture produced in the first mixing chamber and / or main mixing chamber reaches the application elements can be further reduced because the application elements of a boom are not fed by a common nozzle pipe, but by different lines, referred to here as the application line or also as the nozzle line. A conventional long nozzle pipe running lengthwise along the boom for feeding multiple application elements, e.g. spray nozzles, can therefore be dispensed with in this design variant. Instead, the application elements are fed via the application lines connected to the distributor outlets in order to supply the application elements with spray liquid via hydraulically parallel partial flows. Since the application lines only pass on partial flows, e.g.By supplying only one or two spray nozzles with spray fluid, these nozzles can be designed with a smaller diameter than a conventional nozzle pipe, thus enabling correspondingly higher delivery pressures and higher delivery speeds. This can even reduce the average time delay.

[0051] Second, differences in the time delays until a mixture created in the first mixing chamber and / or main mixing chamber reaches the individual application elements, which leads to the aforementioned butterfly effect, can be prevented or at least reduced. This is because a mixture of spray liquid does not reach the application elements one after the other, as would be the case when using a conventional common nozzle pipe. Instead, they are fed via the application lines to supply spray liquid to the application elements via hydraulically parallel partial flows.

[0052] In a further preferred embodiment, the discharge lines are designed, preferably dimensioned, such that the partial flows assigned to a first mixing chamber or, where applicable, fluid distributor, exhibit essentially the same pressure drop and the same time delay on their separate partial flow paths from the distributor outlets to the respective discharge elements until the partial flows arrive at the respective discharge element. The same time delay can be understood as differences in the time delays of less than 5 seconds, preferably less than 3 seconds. These discharge lines can be designed accordingly by appropriately determining the length and / or diameter of the discharge lines connected to the same mixing chamber. The diameter of the discharge lines is preferably the same.

[0053] In a further design variant, each of the application elements is fluidly connected to one of the distributor outlets via a separate application line. In other words, each application line in this variant connects exactly one application element to one distributor outlet. According to this design variant, the application lines therefore have no branching between the distributor outlet and the application element. Differences in the time delays until the spray liquid reaches the individual application elements can be particularly advantageously reduced and, depending on the design, even eliminated.

[0054] In an alternative embodiment, at least one of the discharge lines, preferably all discharge lines, each have at least one branching point that provides a plurality of line branches, with each line branch connecting the branching point to a discharge element. At the branching point, the partial volume flow coming from the distributor outlet is divided again. Compared to separate discharge lines for all discharge elements, the installation space required for the discharge lines can be optimized here. The branching point can be designed in the manner of a Y-branch or in the manner of a T-branch, for example by means of a T-piece or a suitably designed connecting piece. In a preferred embodiment, exactly one such branching point is provided for each discharge line.

[0055] In a further embodiment, the number of distributor outlets of the fluid distributor or the mixing chamber with integrated fluid distributor function can be in the range of 4 to 16 or in the range of 6 to 12. This allows for an advantageous compromise between short delay times and the number of required mixing chambers. Depending on the total number of application elements, several mixing chambers distributed along the longitudinal direction of the boom are required.

[0056] In a further embodiment, the discharge lines connected to the same fluid distributor or to the same mixing chamber with an integrated fluid distributor function each have the same length. In other words, in this embodiment, all discharge lines of a fluid distributor or of a mixing chamber with an integrated fluid distributor function have the same length, whereas optionally, the discharge lines of different fluid distributors or mixing chambers with an integrated fluid distributor function can be of different lengths. In this case, all discharge lines of a fluid distributor or of a mixing chamber with an integrated fluid distributor function can preferably have the same diameter and accordingly have the same pressure drop within the discharge line.This offers the advantage that differences in the time delays until the spray liquid exiting from the first mixing chamber reaches the application elements are avoided or at least reduced.

[0057] According to one embodiment, however, all discharge lines of the spray device are the same length. In other words, in this variant, all flow paths through the discharge lines between a discharge element and the respective distributor outlet are the same length. This offers the advantage that the partial flow paths from the distributor outlet to the discharge element are the same length for all discharge elements, even though the spatial distances of the discharge elements to the distributor outlet through which they are fed can sometimes vary considerably. It is particularly preferred if all discharge lines of the spray device are the same length and have the same diameter, and accordingly, the same pressure drop within the discharge line. Consequently, differences in the time delays until the spray liquid emerging from the distributor outlets reaches the discharge elements fed via them can be advantageously prevented.

[0058] In a preferred further embodiment, the delivery lines are designed as hoses and / or flexible lines, or at least comprise sections designed as hoses and / or flexible lines. This enables a cost-effective, space-saving attachment of the delivery lines to the boom. Alternatively, the delivery lines can also be designed as pipes or comprise pipelines, for example, made of a metallic material.

[0059] In a further embodiment, the discharge lines or at least some of the discharge lines have a non-straight path, or in other words, a curved path. For example, the discharge lines or at least some of the discharge lines can have at least one section that runs in the longitudinal direction of the boom along one of the booms and at least one section that runs in the vertical direction along one of the booms. Furthermore, there is the optional possibility for at least some of the discharge lines to be S-shaped or meandering.

[0060] In a further embodiment, the discharge lines can have an inner diameter of less than 10 mm, more preferably less than 6 mm. The inner diameter can be, for example, 4 mm. This allows significantly higher flow velocities to be achieved compared to conventional nozzle pipes. In a further embodiment, the discharge lines can have a minimum length of 25 cm, or at least 50 cm, or at least 1 meter.

[0061] As already stated above, it is particularly advantageous if the discharge lines are of the same length. In a further embodiment, the discharge lines differ in length by no more than 30%, which also advantageously reduces the differences in the time delays until spray liquid reaches the discharge elements via the discharge lines compared to a conventional nozzle pipe.

[0062] In a further embodiment, the discharge lines are designed, preferably dimensioned, such that the pressure drop in the discharge lines from the distributor outlets to the respective discharge element is a maximum of 2 bar, more preferably a maximum of 1.5 bar. This can be achieved by appropriately selecting the diameter and length of the discharge line. This improves the most even application of the spray liquid.

[0063] Alternatively or additionally, the discharge lines can be designed such that the time delay between the partial streams on their flow path from the mixing chamber to reaching the respective discharge elements is a maximum of 5 seconds, more preferably a maximum of 2 seconds, and more preferably a maximum of 1 second. This can be achieved by appropriately selecting the diameter and length of the discharge line, taking into account the usual fluid pressure at the outlet of the mixing chamber during spraying operation. This enables fast response times when switching the spray boom on and off or when changing the spray fluid.

[0064] In a further advantageous embodiment, the fluid distributors and / or the first mixing chambers of the subsections are each arranged on the subsection, optionally also arranged centrally in the longitudinal direction of the boom on the subsection. In other words, the mixing chambers and / or fluid distributors are arranged centrally in the longitudinal direction of the group of dispensing elements that are fluidically connected to the fluid distributor. This enables a compact attachment of the dispensing lines to the boom.

[0065] The longitudinal direction of the boom is understood here as the direction in which the boom extends and in which the application elements, e.g., the spray nozzles or nozzle bars, are arranged at a distance from one another along the boom. The working width of the spray boom is determined by the length of the spray boom along its longitudinal direction when unfolded. The vertical direction of the boom is understood as the direction perpendicular to the longitudinal direction of the boom and perpendicular to the direction of travel of the field sprayer.

[0066] It is also possible for spray nozzles to be assigned to the central section for spraying and / or finely distributing the spray liquid. It is likewise possible for one or more first mixing chambers and / or discharge lines as described above to be assigned to the central section, which can optionally also be arranged on the central boom. The central section can thus also form a separate subsection of the spray boom. Alternatively, the discharge elements of the central section, or at least a subset thereof, can be assigned to one or more mixing chambers of the booms, so that the discharge lines supplying the discharge elements on the central section also extend from a distributor outlet of a first mixing chamber or fluid distributor on the boom to the central section.

[0067] Furthermore, the following further aspects are disclosed: The dispensing element can be a spray nozzle or a nozzle carrier (also referred to as a nozzle block), in which at least one spray nozzle is mounted. The dispensing elements can be separately controllable in order to be able to switch them on and off individually for spraying. For this purpose, the dispensing element can comprise a switching valve or controllable orifice for controlling the flow. The dispensing elements can optionally be controllable and / or regulated by means of pulse width modulation. The dispensing elements are mounted at a distance from one another in the longitudinal direction of the spray boom, for example at intervals of 25 cm or 50 cm.

[0068] The spray boom can be mounted directly or indirectly on a carrier vehicle, movable about a pivot axis (A) running in the direction of travel. Alternatively or additionally, the two lateral booms can each be rotatably connected to a central section of the spray boom via a vertical pivot axis.

[0069] Each boom can in turn have several boom sections that can be folded in towards each other in the transport position and unfolded into the working position and are connected by joints, so that each of the two booms of a spray boom can be folded, preferably folded multiple times, by folding the respective boom sections at the joints by 180° for the transport position or unfolding them into a stretched position for the working position. When unfolded, the spray boom extends transversely to the direction of travel of the field sprayer. A partial section according to the embodiment described above can correspond to such a boom section or to a partial width of the boom or spray boom. It is known from the prior art that booms or spray booms can be divided into partial widths so that it is not always necessary to work at the full working width.However, the aforementioned boom sections or boom sections can also each comprise several of the aforementioned sections and, accordingly, several mixing chambers with associated discharge elements. This allows the length of the discharge lines to be reduced.

[0070] According to a further aspect, the invention further relates to an agricultural field sprayer comprising a spraying device as described in this document. The field sprayer can be self-propelled, towed, or mounted on a tractor. The self-propelled spreading machine can also be an autonomously driving agricultural machine, for example, a fully autonomous or semi-autonomously driving agricultural machine.

[0071] The spray boom of the spraying device and / or the field sprayer has a large working width, i.e. a working width that is significantly greater than the width of the carrier vehicle or the field sprayer, e.g. a multiple of the width of the carrier vehicle. The field sprayer can comprise, in a manner known per se, an actuating device, e.g. a pneumatic or hydraulic cylinder, by means of which an actuating force can be generated in order to move the distribution boom about the pivot axis. For movably mounting on the carrier vehicle, the spray boom can, for example, be mounted on a carrier, which in turn is coupled, for example, to a body or frame section or a frame construction of the carrier vehicle and / or to a rigidly or movably mounted support section of the carrier vehicle.

[0072] At least one distance sensor for measuring the distance to the ground or crop can be arranged on the boom, e.g., in the form of an ultrasonic sensor. The field sprayer and / or the spray boom can further comprise, in a conventional manner, at least one sensor device for detecting a rotational position and / or a rotational speed and / or an acceleration of the distribution boom, e.g., an acceleration sensor.

[0073] The previously described preferred embodiments, variants, and features of the invention can be combined with one another as desired. Further details and advantages of the invention are described below with reference to the accompanying drawings. They show: The previously described preferred embodiments, variants, and features of the invention can be combined with one another as desired. Further details and advantages of the invention are described below with reference to the accompanying drawings. They show: Figure 1 shows a perspective view of an agricultural field sprayer with a chassis having a frame construction and a spraying device; Figure 2 shows a fluid diagram of a spraying device of an agricultural field sprayer according to one embodiment; Figure 3 shows a schematic view of a spraying device with two first mixing chambers and connected discharge lines according to a further embodiment; Figure 4a shows a schematic view of a first mixing chamber with connected supply lines and discharge lines according to a further embodiment; and Figure 4B shows a schematic view of a mixing chamber and a fluid distributor with connected supply lines and discharge lines according to a further embodiment; Figure 5 shows a schematic view of a first mixing chamber with connected supply lines and discharge lines with a branching point according to a further embodiment;Figure 6 is a schematic view of a supply line with a gradually decreasing inner diameter according to another embodiment; Figure 7A is a perspective view of a mixing chamber of the spray device according to an embodiment of the invention; Figure 7B is a sectional plan view of the mixing chamber of Figure 7B. Figure 7A ; Figure 7C a side view in section of the mixing chamber from Figure 7A ; and Figure 8 shows the embodiment of the Figure 2 with signal and command transmission elements.

[0074] Identical or functionally equivalent elements are partly designated by the same reference numerals in the figures and partly not described separately.

[0075] Figure 1shows in a perspective view a variant of an agricultural field sprayer 1 with a chassis 3 having a frame construction, wherein the chassis 3 also has a chassis 2. The field sprayer 1 is designed here as a self-propelled field sprayer and comprises a cabin 4 with an operating station for an operator and a drive device 5 (e.g. engine). In the rear area, the field sprayer 1 comprises a spray boom 11 which is in a working position and extends transversely to the direction of travel 6 in a large working width, e.g. 24 meters or more, and which can be pivoted about a pivot axis A extending in the direction of travel by means of an adjusting device. The spray boom 11, also referred to as a spray boom arrangement, is height-adjustable relative to the chassis 3 by means of a height-adjustable parallelogram linkage 9. A spraying device according to the invention is also mounted on the chassis 3, wherein in the Figure 1 Of these, only the spray boom 11 and one storage tank 7 of several storage tanks are shown. The spray boom can be pivoted about an axis pointing in the direction of travel A and comprises a central section and two lateral arms, each of which has a plurality of dispensing elements for spraying and / or finely distributing the spray liquid. Furthermore, a control device 8 is provided, which is in signal communication with the individual components of the spraying device, such as the dispensing elements, pumps, valves, flow meters, in order to appropriately control them for dispensing spray liquid. The control device 8 serves in particular to control the various dosing systems, as explained in more detail below.

[0076] A particularly preferred embodiment of a spraying device is shown in Figure 2The spraying device 10 comprises several dosing systems to enable the application of different mixing ratios of spray liquid with minimal delay, depending on the area and via direct feed. Figure 2 shows a fluid diagram of the embodiment. The spray boom and the booms are shown in the fluid diagram of the Figure 2 not shown.

[0077] The Figure 2 The exemplary spraying device shown has a supply line 100 for spraying liquid with a section 110 extending in the longitudinal direction of the spray boom and guided along the spray boom 11, the inner diameter of which gradually decreases in the flow direction. This is the second ring line 100 described below with the section 110, which in Figure 6 is described in more detail.

[0078] At the Figure 2In the spraying device 10 shown, the spray boom 11 is divided along its longitudinal direction B into several sections 19. Here, there are four sections 19, for example. A plurality of dispensing elements 13 are arranged on each section 19, and each dispensing element 13 is assigned to exactly one section 19. Two mixing chambers 20 with integrated fluid distribution function are arranged on each boom, hereinafter also referred to as first mixing chambers. An exemplary embodiment of such a first mixing chamber is shown in the Figures 7a-cThe spray liquid mixed by these first mixing chambers 20 is discharged in the form of several hydraulically parallel partial streams via the distributor outlets of the first mixing chambers 20, to which the discharge lines 15 are connected to supply the discharge elements 13. The discharge element 13 can be a spray nozzle or a nozzle carrier in which at least one spray nozzle is mounted.

[0079] As mentioned, the spraying device 10 comprises several dosing systems to enable flexible direct feed with area-specific application.

[0080] The spraying device 10 comprises a first dosing system 30, with a first storage container 31 for a first spray liquid 37 and a first dosing device 32, 33. The first storage container can be, for example, the tank 7 from Figure 1The first reservoir 31 is the main tank for a first premixed spray liquid, e.g., a main spray liquid mixture. This is the mixture that will be largely applied during an upcoming spraying process. Furthermore, a connection for or a coupling to, for example, an induction hopper (not shown) can be provided on the first reservoir to enable the main tank to be filled accordingly.

[0081] The first dosing device here comprises a flow meter 33 and a pressure generating unit, here, for example, a pump 32, for conveying the first spray liquid 37. As an alternative to the pump 32, it would also be conceivable for the conveying pressure to be generated by means of a compressor, which is, for example, operatively connected to the first storage container 31.

[0082] The first mixing chambers 20 are each fluidically connected on the inlet side via the lines 17 to a first supply line 35, to which the first spray liquid 37 can be fed from the first storage container 31 by means of the first metering device 32, 33. The first supply line 35 is designed here as a ring line or circulation line, which has a section extending in the longitudinal direction of the spray boom 11 and guided along the spray boom 11, at which section several branching points 36 are provided corresponding to the first mixing chambers 20. A design as a stub line would also be possible. At a branching point 36, spray liquid 37 is branched off for each of the first mixing chambers 20 by means of the lines 17. A circulation valve 34 is arranged in the first supply line 35.This is controlled by the control device 8 in such a way that it is closed when the spray nozzles 13 are open in order to generate a sufficient spray pressure, and it is open when the spray nozzles 13 are closed in order to prevent, for example, deposits in the system.

[0083] The spray device 10 further comprises a second dosing or supply system 40, comprising a second storage container 41 for a second spray liquid 47 and a second dosing or fluid supply device 42, 43. The second spray liquid 47 is, for example, fresh water (clear water) and the second storage container 41 is a water tank, although another carrier liquid for an active ingredient can also be used.

[0084] The second dosing or fluid supply device comprises a flow meter 43 and a pressure generation unit, preferably in the form of a pump 42 (charging pump for liquid delivery). The pump 42 could also be replaced by deliberately pressurizing the storage tank 41, e.g., using a compressor. A check valve 45 is arranged downstream of the pump 42, which serves to prevent unwanted mixing of the fresh water with the crop protection agent of the third dosing system 50 described below. This second dosing or supply system 40 does not necessarily serve to provide a precise or well-metered amount of spray liquid, but essentially only generates pressure to provide fresh water 47. Precise quantity control as in the first or third dosing systems 30, 50 is not provided here, but would be possible.A dosing valve is therefore not provided, but would be possible to increase dosing accuracy.

[0085] The spraying device 10 further comprises a third dosing system 50, comprising at least one third dosing device 52, 53, 54 and at least one third storage container 51 and / or at least one container receptacle for releasably holding a third storage container 51. The third spray liquid here is a crop protection agent, for example a growth regulator, fungicide, insecticide, pesticide and / or the like. The third storage container can be a canister. The third dosing system 50 can comprise a container receptacle which is provided on the field sprayer in order to releasably hold the canister as an interchangeable container. The third dosing device comprises a dosing valve 54, a flow meter 53 and a pressure generating unit, preferably again designed as a pump 52. Several such third storage containers orContainer receptacles and several associated third dosing devices must be provided, depending on how many different third spray liquids, for example how many different plant protection products, are to be applied via direct feed.

[0086] The spray device of the embodiment of the Figure 2further comprises a further mixing chamber 70, referred to here as the main mixing chamber. The second spray liquid 47 can be supplied to the main mixing chamber 70 on the inlet side by the second dosing or fluid supply device 42, 43 via a supply line of the second dosing system 40, and the at least one third spray liquid 57 can be supplied to the main mixing chamber 70 on the inlet side by the at least one third dosing device 52, 53, 54 via one or more corresponding supply lines of the third dosing system 50. On the outlet side, the main mixing chamber 70 is connected to a second supply line 100 in order to supply the spray liquid mixture generated by the main mixing chamber 70 to the first mixing chambers 20, in particular to their second inlets. In the present example, the second supply line 100 is designed as a circulation line or ring line, in which a pump (feed pump) 102 and a throttle valve 101 are also arranged.The main mixing chamber 70 is designed to mix, preferably homogeneously mix, the second and third spray liquids 47, 57 supplied to it via the second dosing or supply system 40 and the third dosing system 50, and then to discharge the mixed spray liquid into the second circulation line (ring line) 100.

[0087] The second circulation line (ring line) 100 comprises a section 110 extending in the longitudinal direction of the spray boom 11 and guided along the spray boom 11, which section has several branching points 103 for branches 18 for supplying a respective section 19 and part of the application elements 13 with spray liquid. These branches 18 are thus lines which each fluidically connect a branching point 103 of the second circulation line 100 with the second inlet of one of the first mixing chambers 20. The inner diameter of the section 110 becomes gradually smaller in the flow direction (see description of Figure 6 ).

[0088] The first mixing chambers 20 are thus fluidically connected on the inlet side via their first inlet to the first circulation line 35 and on the other hand via their second inlet to one of the branches 18 of the second circulation line 100.

[0089] The spray liquid flowing from the main mixing chamber 70 into the second circulation line 100 is pumped by the pump 102 in the direction of the branch points 103. The portion of the spray liquid that was not fed to the first mixing chambers 20 via the branches 18 flows back towards the throttle valve 101 via the second circulation line 100 during circulation operation and, when the pump 102 is activated, can continue to circulate in the second circulation line 100 via the main mixing chamber 70. The spray liquid is thus circulated in the second ring line 100 in order to have the correct / desired liquid, i.e. the liquid with the correct / desired concentration, available as quickly as possible, i.e. without any delay, at the required position on the spray boom.

[0090] The spray device 10 further comprises fourth metering devices 60 arranged in each of the branches 18, each comprising a flow meter 63 and a metering valve 64. These fourth metering devices 60 serve to control and / or regulate a quantity of second and / or third spray liquid supplied to the respective associated first mixing chambers 20 from the second supply line 100, which were previously mixed in the main mixing chamber 70. For this purpose, the control device 8 is in signal communication with the flow meters 63 and the metering valves 64 and controls the latter accordingly. The throttle valve 101 is arranged downstream of the branch points 103, before the second supply line 100 flows back into the main mixing chamber 70.The fourth metering devices 60 serve to compensate for flow differences between individual branches 18, if necessary, and / or to supply the respective first mixing chambers 20 with only the quantity of second and / or third spray liquid 47, 57 required for the specific application to the respective part of the area.

[0091] To implement a partial area-specific application of spray liquid, the control device 8 is designed to selectively supply all application elements 13 or application elements 13 of selected sections 19 by controlling the first metering device 32, 33, the second metering or fluid supply device 42, 43 and the at least one third metering device 52, 53, 54 and the fourth metering device 60, with a mixture of at least two of the spray liquids 37, 47, 57 in a definable mixing ratio or only one of the spray liquids. This will be explained below in connection with Figure 8explained in more detail.

[0092] The Figure 6 shows a schematic view of a possible embodiment variant of the second ring line 100, as advantageously used in the embodiment according to Figure 2 can be used. Only a section of the ring line 100 is shown here. The pump 102 is located downstream of the main mixing chamber 70, whereby, in contrast to the embodiment of the Figure 2 Here, an optional filter element 104 is shown downstream of the pump 102. In the description of the embodiment according to Figure 2It has already been established that the second ring line 100 has a section 110 extending in the longitudinal direction of the spray boom 11 and guided along the spray boom 11, which section has a plurality of branch points 103 for branches 18 for supplying a portion of the application elements 13 with spray liquid. The second ring line 100 is characterized in that the inner diameter of the section 110 gradually decreases in the flow direction.

[0093] The ring line 100 thus has different cross-sections in order to achieve the highest possible, uniformly high flow rates. This has the advantage of quickly having the desired agent available at all sections 19 or their associated mixing chambers 20 and application elements 13 when adjusting the spray liquid, e.g., when adding a crop protection agent from the third dosing system 50 or adjusting the mixing ratio. This, in particular, reduces the system's inertia to a low level when adjusting the liquid concentration, thus eliminating the need to provide a separate circulation line for each crop protection agent, as is the case, for example, with prior art systems.

[0094] Here, pipe section 111 and the pipe section upstream in the flow direction between pump 102 and the first branch point 103 have a larger inner diameter than the pipe sections 112, 113, and 114 following pipe section 111 in the flow direction, while the following pipe section 115 has an even smaller inner diameter. For example only, pipe section 111 and the pipe section upstream can each have a nominal diameter DN (French: Diamètre Nominal) of DN8, the pipe sections 112, 113, and 114 following in the flow direction each have a nominal diameter of DN6, while the following pipe section 115 has a nominal diameter of DN4. The pipe section 116 following pipe section 115 in the flow direction leads back to the main mixing chamber 70 (not shown here).

[0095] Measurements on such a spray device show, for example, that the flow velocity in section 110 does not decrease continuously, as would be the case with a line with a constant inner diameter, but fluctuates only within a small range and, in particular, is approximately the same at the last branch point 103 seen in the direction of flow as at the first branch point 103.

[0096] The following measured values ​​of an exemplary embodiment are given purely as an example to illustrate the effect of the section-by-section decreasing inner diameter of section 110. Upstream of pipe section 111, the inner diameter is DN8 and the flow velocity is 1.7 m / s. Pipe section 111 also has an inner diameter of DN8 and at the branch point 103 at the end of pipe section 111, the flow velocity is only 1.4 m / s. Pipe section 112 downstream of pipe section 111 only has an inner diameter of DN6 and at the branch point 103 at the end of pipe section 112, the flow velocity is approximately 2 m / s due to the smaller inner diameter. Pipe section 113 also has an inner diameter of DN6 and at the branch point 103 at the end of pipe section 113, the flow velocity has dropped again to 1.6 m / s.Pipe section 114 also has an inner diameter of DN6, and at branch point 103 at the end of pipe section 114, the flow velocity has dropped further to 1.2 m / s. Pipe section 114 downstream of pipe section 115 only has an inner diameter of DN4, and at branch point 103 at the end of pipe section 114, the flow velocity has increased again to 1.7 m / s due to the even smaller inner diameter, i.e., to a value similar to the beginning of pipe section 111.

[0097] Figure 3 shows a schematic view of a spraying device 10 with two first mixing chambers 20 and connected discharge lines 10 according to an embodiment.

[0098] The spraying device 10 is used for the metered application of spray liquid on agricultural land. Figure 3 The spraying device 10 shown is designed for a field sprayer which has a smaller working width than the one shown in Figure 1 The spraying device 10 comprises the pivoting spray boom 11, which has two lateral arms 12, each of which has a plurality of application elements 13 for spraying and / or finely dispersing the spray liquid. The application elements 13 generate a spray cone directed towards the ground or the crop for the desired distribution of the active ingredient. The application elements 13 are in Figure 3 only schematically shown based on the spray cone they produce (could also be so-called spray fans). The longitudinal direction of the spray boom 11 or the booms 12 is indicated by arrow B, the vertical direction of the spray boom 11 or the booms 12 by arrow V. The two lateral booms 12 are each rotatably connected to a central section 11a of the spray boom 11 via a pivot axis A running in the direction of travel.

[0099] A first mixing chamber 20 with an integrated fluid distribution function is arranged on each boom 12. The first mixing chambers 20 each comprise a first inlet 21 for admitting a first liquid stream, a second inlet 22 for admitting a second liquid stream, and several outlets (distributor outlets) 23 for discharging the mixed liquid stream as several partial streams 23a. The mixing chamber and the fluid distributor are designed here as a structural unit. The first mixing chambers 20 can be similar to those of the embodiment variant of Figure 2accordingly, whereby instead of four, only two such first mixing chambers 20 are provided. The two spray liquids to be mixed are fed to the mixing chambers 20 via supply lines 17, 18. The supply lines are thus connected to the inlets 21, 22. Discharge lines 15 are connected to the previously described outlets (distributor outlets) 23. The structure of the spraying device or the liquid plan upstream of the first mixing chambers 20 can be Figure 2 and is therefore not shown in detail here except for the supply lines 17, 18 in order to clarify the aspect of the individual discharge lines 15.

[0100] The first mixing chambers 20 shown with an integrated fluid distribution function are designed for mixing two spray liquids and for distributing or dividing the mixed spray liquids into several partial streams, which are discharged via the distributor outlets 23 as hydraulically parallel partial streams. The first mixing chambers 20 thus each have two functions: mixing the supplied spray liquids and subsequently distributing, which can also be referred to as dividing or branching, the mixed spray liquid into several partial streams.

[0101] Each of the dispensing elements 13 is fluidically connected to one of the distributor outlets 23 via a separate dispensing line 15. For the sake of clarity, not every dispensing element 13, not every dispensing line 15, and not every distributor outlet 23 is separately identified with a reference symbol. However, the example shown shows a total of 16 dispensing elements 13 arranged at equal distances in the longitudinal direction B of the spray boom 11, each of which is supplied with spray liquid via its own dispensing line 15. Accordingly, each first mixing chamber 20 in this example has eight distributor outlets 23, and eight dispensing lines 15 are connected to each first mixing chamber 20. The number of first mixing chambers 20, distributor outlets 23, dispensing elements 13, and dispensing lines 15 are only examples.In the case of spray booms with larger working widths, a corresponding number of first mixing chambers 20 per boom and a higher number of discharge elements 13 and discharge lines 15 can be provided and / or the number of distributor outlets 23 per first mixing chamber can be varied.

[0102] The first mixing chamber 20 mixes two of these supplied spray liquid streams and branches the mixed spray liquid stream created inside the mixing chamber into substreams and discharges them via the distributor outlets 23. These substreams are then conveyed via the discharge lines 15 on separate partial flow paths from the first mixing chamber 20 to the respective discharge elements 13. The provision of separate discharge lines 15 instead of a conventional nozzle line that feeds several discharge elements sequentially offers the advantage that these discharge lines 15 can be designed with a smaller diameter, since they only need to convey a partial amount of the spray liquid, namely only the spray liquid that is discharged via a single discharge element 13.The flow velocity in the individual discharge lines 15 is correspondingly faster compared to a nozzle pipe, so that a faster reaction time can be achieved overall.

[0103] These discharge lines 15 are designed here as hose lines and / or as flexible lines with a non-straight (curved) path. The discharge lines are dimensioned such that a pressure drop of a maximum of 1 bar occurs on the path from the distributor outlet 23 to the respective discharge element 13, and a time delay of the partial flows for their flow path from the first mixing chamber 20 until they reach the respective discharge elements 13 is a maximum of five seconds. The first mixing chambers 20 are arranged centrally in the longitudinal direction B of each of the booms 12.

[0104] It has already been noted above that in Figure 3a spray boom 11 with a small working width is shown. In a further embodiment (not shown), which is suitable for larger working widths, such as for the Figure 1 As is advantageous in the spray boom 11 shown, each boom is divided into several subsections, wherein a plurality of dispensing elements are arranged at each subsection, and each dispensing element is assigned to exactly one subsection. In this embodiment, each boom has several first mixing chambers 20, such that a first mixing chamber 20 is arranged at each subsection, and the dispensing elements assigned to the respective subsection are connected to the first mixing chamber 20 of this subsection via corresponding dispensing lines. Figure 2shows a corresponding example with two first mixing chambers 20 per boom. Thus, each of the booms 12 can have two, three, four, or more first mixing chambers 20, which are arranged on the boom 12 at a distance from one another in the longitudinal direction B of the boom. Accordingly, a group of dispensing elements assigned to a specific subsection and first mixing chamber 20 is arranged longitudinally adjacent to another group of dispensing elements assigned to an adjacent subsection and an adjacent first mixing chamber.

[0105] For this purpose, each boom 12 can have several boom sections connected by joints that can be folded in toward each other in the transport position and unfolded in the working position, so that each of the two booms of a spray boom can be folded multiple times by folding the respective boom sections at the joints by 180° for the transport position or unfolding them into an extended position for the working position. In the unfolded state, the spray boom extends transversely to the direction of travel of the field sprayer.

[0106] The aforementioned subdivision into subsections can correspond to this subdivision into rod sections that are movable relative to one another. Alternatively, each of these rod sections can have several, i.e. at least two, subsections, so that at least two first mixing chambers with associated dispensing elements are arranged in the rod section. This allows the line length of the dispensing lines to be reduced. The dispensing elements 13 arranged on the central part can also correspond to a subsection or, as in Figure 3 shown, be assigned to subsections.

[0107] It is particularly advantageous to design the discharge lines 15 so that they are of equal length, so that the flow path from the distributor outlet 23 to the respective discharge element 13 is of equal length for all discharge lines 15. Differences in the time delay until spray liquid has covered the flow path from the distributor outlet to the discharge elements can thus be avoided. Such an embodiment with discharge lines of equal length is shown in the Figure 2 , 4A and 4B shown.

[0108] Figure 4A shows a schematic view of a first mixing chamber with connected supply lines and discharge lines according to a further embodiment.

[0109] In Figure 4AAn embodiment is also shown in which the discharge lines 15 have the same length and the same diameter, so that the flow path from the distributor outlet 23 to the respective discharge element 13 is the same length for all discharge lines 15. Differences in the time delay until spray liquid has covered the flow path from the distributor outlet to the discharge elements can thus be avoided. To clarify this aspect, only a single first mixing chamber 20 with associated discharge lines 15 and discharge elements 13 is shown, as well as with a metering device 60 for one of the supply lines. The other (not shown) first mixing chambers 20 and elements of the spray device 10 and the spray boom 11 can be designed as previously described.

[0110] A first supply line 17 is connected to the first inlet 21 of the first mixing chamber 20 in order to supply a first spray liquid, e.g. a main mixture from a main tank of the field sprayer, to the first mixing chamber 20. A second supply line 18 is connected to the second inlet 22 of the first mixing chamber 20 in order to supply a second spray liquid, e.g. a pre-diluted crop protection agent, from another storage container, e.g. a canister, to the first mixing chamber 20. Furthermore, a metering device 60 is shown, comprising a flow meter 63 and a metering valve 64, in order to be able to meter the amount of second spray liquid introduced into the first mixing chamber 20 as required. In order to enable a partial area-specific application, the metering system 60 can, for example, be controlled by the control device 8 if required, so that, for example,In addition to the main mixture supplied via line 17, a crop protection agent is metered via line 18 and mixed with the main mixture in the first mixing chamber 20. The crop protection agent can, for example, be selectively supplied to only one of the first mixing chambers 20 or a subset of the first mixing chambers 20 of the spray boom, so that the crop protection agent is applied for area-specific application only via those application elements 13 that are arranged downstream of this one first mixing chamber 20 or this subset of first mixing chambers 20.

[0111] In the example shown, only six dispensing elements 13 are assigned to the first mixing chamber 20 and connected to the first mixing chamber 20 via corresponding dispensing lines 15. Although the spatial distances of the individual dispensing elements 13 to the distributor outlet 23 of the first mixing chamber 20, via which they are fed, sometimes vary greatly, all six dispensing lines 15 are the same length and have the same diameter. Consequently, all dispensing lines 15 have the same pressure drop and the same time delay until spray liquid reaches the dispensing elements 13. Accordingly, a particularly uniform dispensing of spray liquid can be achieved. The other first mixing chambers 20 (not shown) of the spraying device can be constructed identically. The dispensing lines 15 of all first mixing chambers 20 can have the same length.

[0112] As already stated above, it is also possible, alternatively, for example, for all discharge lines of a first mixing chamber 20 to have the same length, but for discharge lines of different mixing chambers to have different lengths. The resulting different flow times through the discharge lines of different first mixing chambers 20 can be taken into account by the control device 8 when scheduling the discharge elements 13. For example, offset values ​​can be stored in the control device 8, e.g., a central control unit for controlling the spraying process, which is in signal communication with the discharge elements 13 for controlling them, which provide a measure of the different flow times for each first mixing chamber.Accordingly, by using such offset values, the switching times for the application elements can be precisely maintained if individual sections of the boom are controlled individually, so that despite partially different lengths of the application lines, the spray liquid emerges from the application lines essentially at the same time.

[0113] Figure 4Bshows a schematic view of a mixing chamber and a fluid distributor with connected supply lines and discharge lines according to a further embodiment. The special feature of this embodiment is that instead of a mixing chamber with an integrated fluid distributor function, this function is realized by two separate components 20A, 28, which together form a device 20 for mixing at least two spray liquids and for distributing the mixed spray liquids to several partial streams. For this purpose, a first mixing chamber 20A, which has only one outlet 24, and a fluid distributor 28 are arranged downstream of the first mixing chamber 20A as a separate component. In this case, spray liquid emerging from an outlet 24 of the first mixing chamber 20A is supplied to the inlet 29 of the fluid distributor 28. At the distributor outlets 23 of the fluid distributor 28, the discharge lines 15 are then again connected, as in connection with Figure 4Aalready described. Also in the version of the Figure 2 Instead of the first mixing chambers with integrated fluid distribution function, two separate components can be provided that have the same functionality.

[0114] Figure 5 shows a schematic view of a first mixing chamber 20 with connected discharge lines according to a further embodiment. The special feature of this embodiment is that the discharge elements 13 are not connected via separate discharge lines, but rather that the discharge lines 16 each have a branching point 16a. To clarify this aspect, Figure 5 Again, only one of the first mixing chambers 20 with associated discharge lines 16 and discharge elements 13 is shown. For better clarity, only some of the components are marked with reference symbols.

[0115] As in Figure 5 As can be seen, all discharge lines 16 of the first mixing chamber 20 each have a branching point 16a. Each of the branching points 16a provides two line branches 16b, 16c. The branching point 16a is designed in the manner of a Y-branch or T-branch, so that each line branch 16b, 16c is connected to a discharge element 13 at its free end. The partial flow coming from the distributor outlet 23 thus splits again into two further partial flows at the branching point 16a. Here, too, all discharge lines 16 of the first mixing chamber 20 are identical, so that the time delay until spray liquid from a distributor outlet 23 reaches the respective discharge element 13 is the same. The other first mixing chambers 20 or a subset thereof can be constructed identically.

[0116] Figure 7Ashows a perspective view of a first mixing chamber 20 of the spray device according to an embodiment of the invention. Reference is further made to the Figure 7B , which shows a top view in section of the mixing chamber, as well as the Figure 7C , which is a side view in section of the mixing chamber Figure 7A In connection with the Figures 7A to 7C The first mixing chamber is also referred to as the mixing chamber for short.

[0117] The cylindrical mixing chamber 20 comprises a first inlet 21 for admitting a first liquid stream, a second inlet 22 for admitting a second liquid stream and a plurality of outlets (distributor outlets) 23 for discharging the mixed liquid stream as a plurality of partial streams 23a. The first liquid stream is in Figure 7C by the arrows with black arrowheads and the second fluid stream by arrows with white arrowheads.

[0118] Here, the first inlet 21 is arranged centrally on a first side of the mixing chamber 20. The second inlet 22 is arranged on a second side of the mixing chamber opposite the first side, in a central region 26c of the second side. The outlets 23 are also arranged on the second side of the mixing chamber 20, which forms the bottom of the mixing chamber.

[0119] The second side or the bottom of the mixing chamber 20 is formed by a circular, flat base plate 26, which surrounds a raised portion 27 that projects or extends into the interior of the mixing chamber 20. The circular base plate 26 and the raised portion 27 can also be designed as a single component. The base plate has outwardly projecting fastening sections 26b with through holes, into each of which a pin-shaped fastening element, e.g., a screw or bolt, can be guided to attach the mixing chamber to a boom 12 of the spray boom 11.

[0120] A cylindrical cover 25 is seated on the base plate 26, which cover has the first inlet 21 in the center in the form of a connection, e.g. a connecting piece, for a fluid line. The elevation 27 in the bottom region of the mixing chamber 20 is designed as a dome-shaped or hood-like elevation. At its tip or distal end, the elevation has a closed, curved central region 27b, which is arranged flush below the first inlet 21. Below the curved central region 27b, the elevation has a plurality of through-openings or inlet openings 27a, which are arranged in a circle on the lateral surface of the elevation 27. The inlet openings 27a are part of the second inlet 22 or are fluidically connected to it, so that the second liquid flow enters the interior of the mixing chamber 20 via the plurality of inlet openings 27a. In this case, the fluid flow on the second side orThe second inlet 22, arranged centrally below the elevation 27 on the underside of the mixing chamber 20, opens into an inlet channel which extends within the elevation 27, initially toward the opposite first side of the mixing chamber and then bends and splits by approximately 90° in order to direct the incoming second liquid stream to the inlet openings 27a. The inlet openings 27a are arranged on the elevation in such a way that the second liquid stream flows into the interior of the mixing chamber in the form of several partial streams, essentially parallel to the second side and in a fan-like or circular disk-like manner.

[0121] At the same time, the first inlet 21 is arranged centrally on the first side and aligned with the closed central region 27b or the tip of the elevation 27, so that a liquid flow entering via the first inlet 21 at least partially encounters the closed, curved central region 27b of the elevation 27 and is deflected from there in a uniformly distributed manner in the circumferential direction. This leads to the flow paths of the first liquid flow and the flow paths of the second liquid flow crossing each other, which in Figure 7Cis illustrated. The resulting eddies and turbulence lead to the most homogeneous mixing possible of the two liquid streams. The resulting mixed liquid stream is guided out of the interior of the mixing chamber 20 via outlet openings 26a and the adjoining outlets 23, which are each arranged in a circle around the elevation 27 on the base plate 26. The outlets 23 are designed on the underside of the base plate 26 as connections, e.g. as connecting pieces, for fluid lines. In the present case, only six distributor outlets 23 are provided as an example. However, depending on how many separate lines are connected to the mixing chamber 20 for conveying the mixed spray liquid, a different number of distribution connections 23 can of course also be provided, e.g. eight, as described in the following example.

[0122] The mixing chamber 20 described above thus forms a spatial area in which two spray agent streams meet and are mixed with one another. The supply connections for the spray agent streams are arranged and designed on the mixing chamber 20 such that the two spray agent streams are introduced into the interior of the mixing chamber, where they intersect and mix. To enable thorough mixing, the elevation 27 protruding into the interior of the mixing chamber is provided. This elevation, on the one hand, forms a deflection element for the first spray agent stream in order to deflect it perpendicular to an inlet and outlet direction, and on the other hand, serves to fan out the other spray agent stream upon entry into individual partial jets and deflect it in a direction perpendicular to the outlet direction.The resulting eddies and turbulence ensure that the two spray liquids are reliably mixed before they exit as a mixed spray agent stream in the form of individual mixed partial streams via the outlets 23 and are fed to the application lines.

[0123] The mixing chamber 20 is particularly designed not only to mix the supplied liquid streams, but also to divide the resulting mixed spray liquid into a plurality of partial streams 23a, each of which exits the mixing chamber 20 via one of the distributor outlets 23. The mixing chamber thus simultaneously serves as a fluid distributor for dividing a mixed liquid stream into a plurality of partial streams in order to divide the mixture of at least two spray liquids resulting in the mixing chamber into partial streams and to discharge them from the mixing chamber via separate partial flow paths via the plurality of outlets.

[0124] The first inlet 21 and / or the second inlet 22 and / or the outlets 23 can be screwed into the cover 25 or the base plate, or can be welded, glued, soldered, or the like. They can also each have an internal or external thread for mounting the respective line.

[0125] To ensure that the mixing chamber 20, or rather the components of the mixing chamber, can be cleaned as residue-free as possible, they can be made of stainless steel. Plastics with correspondingly low-roughness surfaces would also be conceivable.

[0126] Figure 8 shows the fluid plan of the Figure 2 , supplemented by a control device 8 and signal and / or command transmission elements 8a to illustrate the functioning of the adjustment of the respective liquid quantities to be dispensed by means of the dosing systems.

[0127] A control device 8 is provided to control the spraying process, e.g., to control the dispensing elements 13 and to adjust the respective amounts of liquid to be dispensed by means of the dosing systems. The control device 8 is a program-configured computer unit or computer controller 100, e.g., comprising a job computer.

[0128] The control device 8 can activate and deactivate individual application elements 13 for a specific area when the field sprayer 1 travels across a field and can adjust the spray liquid mixture and quantity applied over a section 19. For this purpose, the control device 8 is in signal and / or communication connection with the application elements 13, with the individual sensor elements, such as the flow meters, and with controllable elements, such as the valves and pumps of the dosing systems. Corresponding signal and / or command transmission elements 8a are each represented by dashed lines. For the sake of better clarity, only some of the signal and / or command transmission elements 8a are shown as examples. Signal and / or command transmission elements for controlling the application elements 13 are not shown. The signal and / or command transmission elements 8a can be controlled via a data bus, e.g.Isobus, or through other lines for signal and data transmission.

[0129] The control device 8 is further configured to receive input commands and control information via a user interface, e.g., an operating terminal, a tablet computer, or via a data interface (not shown), in a manner known per se.

[0130] The control device 8 is configured to appropriately control the dosing devices of the dosing systems 30, 40, 50 and the fourth dosing devices 60 in order to adjust the respective liquid quantities and mixtures to be dispensed by means of the dosing systems.

[0131] The liquid quantities and mixtures to be applied can be specified using corresponding input parameters. These can, for example, specify the quantity to be applied (application rate) of first spray liquid 37 from the main tank 31 and the quantity to be applied (application rate) from the crop protection agent tank 51. Values ​​for these input parameters can be pre-set or entered in various ways: Corresponding values ​​for these input parameters can, for example, be manually specified via a user input by an operator via the user interface and / or read in via a data interface, e.g. from a database, application map or field record file. The database can be a database of the crop protection agent manufacturer. In this case, the control device 8 can also be coupled to a positioning system. Corresponding parameters for the setting can also be determined using camera and / or sensor data, which can, for example,determine a weed infestation and / or a growth stage of the plants.

[0132] The following describes an example of how to adjust the quantities and mixtures of liquids to be dispensed using the dosing systems.

[0133] By entering the input parameters, the quantity of a "main agent" (first spray liquid 37) to be applied per area is first determined. For example, this should be 100 l / ha (100 liters per 10,000 m²). This "main application rate" (first spray liquid 37) is then provided accordingly by the first dosing system 30 and distributed to the first mixing chambers 20. The control device 8 controls the feed pump 32 and the circulation valve 34 accordingly, depending on the measured values ​​of the flow meter 33. Initially, the same quantity of spray liquid is supplied to all first mixing chambers 20. Although the quantity can be adjusted, this can only be done across the entire width of the spray boom. In other words, all first mixing chambers 20 can only be supplied with more or less of the "main agent."

[0134] By entering the input parameters, it can also be determined whether and how much of an additive (third spray liquid 57), e.g., a thistle product, should be applied either to a specific area or to the entire area. A specific area application can be specified, for example, based on a field map. For example, the input parameters specify that 5 l / ha, i.e., 5 liters per 10,000 m² of the additive (third spray liquid 57), should be applied additionally.

[0135] However, since handling such small amounts of additive is difficult, the additive is again mixed with clear water (second spray liquid 47) in the main mixing chamber 70 and thus pre-diluted. The control device 8 is configured to determine a mixing ratio for pre-diluting the additive (third spray liquid 57) based on the applied amount of additive, e.g., 5 l / ha.

[0136] The second dosing or supply system thus expediently serves only to provide a carrier liquid for the additive (third spray liquid 57). If, for example, a mixing ratio of 1 / 10 is defined or specified as pre-dilution, this means that 5 liters of additive require 50 liters of clear water (or similar carrier liquid). The control device 8 achieves this mixing ratio by appropriately controlling the third dosing device 52, 53, 54 to provide the required amount of additive and by controlling the second dosing or fluid supply device 42, 43 to provide the required amount of clear water for pre-dilution of the additive in the main mixing chamber 70. In this case, the pump 42 of the second dosing or fluid supply device 42, 43 is only activated until the correct amount has been detected by the flow meter 43.

[0137] The mixture produced in the main mixing chamber 70 is then conveyed along the second ring line 100 and optionally fed to the first mixing chambers 20 in defined quantities, i.e., for example, in the case of partial area-specific applications, it is fed only to individual first mixing chambers 20 and, for example, fed in different quantities. For this purpose, the control device controls the fourth metering devices 60 accordingly. Furthermore, when feeding the additive to the first mixing chambers 20, the control device 8 takes into account the pre-dilution in the main mixing chamber 70, so that in order to apply 5 liters of additive per hectare across the entire working width, a total of 50 liters of pre-diluted mixture of the second and third spray liquids 47, 57 is fed to the first mixing chambers 20 for an area of ​​1 hectare, not 5 liters.The control device 8 is accordingly configured to adjust the corresponding delivery quantities by controlling and / or regulating the metering valves 53 and 63.

[0138] The control device 8 is further configured to monitor and adjust the following aspects accordingly: The fourth metering devices 60 only meter when at least one downstream spray nozzle 13 is open, or the fourth metering devices 60 meter depending on the number of open spray nozzles 13 and / or depending on the application rate delivered by the spray nozzles 13. This allows, in particular, a targeted adjustment of the rate per section, e.g., per section width.

[0139] The control device 8 is designed to control the second dosing or fluid supply device 42, 43 and / or the at least one third dosing device 52, 53, 54 such that a sum of the flow rate measured with the flow meters 43, 53 of the second dosing or fluid supply device and the at least one third dosing device is equal to the sum of the flow rate measured with the flow meters 63 of the fourth dosing devices 60.

[0140] The fourth metering devices 60 can, in particular, operate in a speed-dependent and / or application-map-dependent manner, so that they define a fixed or variable target value for the liquid quantity as a function of the speed and / or as a function of an application map. It has already been mentioned above that camera data, sensor data, database data, or the like can also be used to determine the input parameters in order to control the application process in a section-specific manner. Data from a positioning system can also be used alternatively or additionally. The invention is not limited to the preferred embodiments described above. Rather, a multitude of variants and modifications are possible, which also fall within the scope of protection defined by the appended claims. Reference symbol list

[0141] 1Agricultural field sprayer, e.g. trailed field sprayer 2Running gear 3Chassis 4Cabin 5Drive system 6Direction of travel 7Storage tank 8Control device 8aSignal and / or command transmission element 9Height-adjustable parallelogram boom 10Spraying device 11Spray boom 11aCentral section 12Side boom 13Distribution element, e.g. spray nozzle 15Distribution line 16Distribution line 16aBranch point 16bLine branch 16cLine branch 17Mixing chamber supply line 18Mixing chamber supply line 19Section, e.g. B. Partial width 20First mixing chamber 20AFirst mixing chamber without fluid distributor function 21First inlet 22Second inlet 23Outlet 23aPartial flows 24Outlet 25Cover 26Base plate, e.g. floor plate 26aOutlet opening 26bFastening area 26cMiddle area 26dOuter area 27Elevation 27aThrough opening 27bMiddle area of ​​the elevation 28Fluid distributor 29Inlet 30First dosing system 31Storage tank, e.g.Main tank 32Pump 33Flow meter 34Circulation valve 35First supply line, e.g. first ring main, circulation line 36Branch point to the mixing chamber 37First spray liquid, e.g. main mix 40Second dosing or supply system 41Storage tank, e.g. fresh water tank 42Pump 43Flow meter 47Second spray liquid, e.g. fresh water 45Check valve 50Third dosing system 51Storage tank, e.g. crop protection product tank 52Pump 53Flow meter 54Dosing valve 57Third spray liquid, e.g. crop protection product 60Fourth dosing device 63Flow meter 64Dosing valve 65Check valve 70Main mixing chamber 100Second supply line, e.g. B. second ring line, circulation line 101Throttle valve 102Pump 103Branch point to the mixing chamber 104Filter 110Line section with decreasing inner diameter 111-116Line section ASwivel axis in direction of travel BLongitudinal direction of the boom VTrectical direction of the boom.

Claims

1. Spraying device (10) for an agricultural field sprayer for the metered application of spray liquid, preferably on agricultural land, comprising a) a swivelling spray boom (11), comprising two side arms (12), each of which has a plurality of application elements (13) for spraying and / or finely distributing the spray liquid, and b) a feed line (100) for spray liquid, comprising a section (110) extending in the longitudinal direction of the spray boom (11) and guided along the spray boom (11), the internal diameter of which section becomes smaller, preferably gradually smaller, in the direction of flow, characterised in that the supply line (100) is a ring line.

2. Spraying device (10) according to claim 1, wherein the section (110) has at least three, further preferably at least four subsections (111-115) with different internal diameters.

3. Spraying device (10) according to any one of the preceding claims, wherein the inner diameter of the section (110) gradually a) becomes smaller by 1 millimetre and / or by 2 millimetres, or b) becomes smaller by nominal width, DN, and / or by 2 nominal widths, DN.

4. Spraying device (10) according to claim one of the preceding claims, wherein the section (110) comprises a plurality of branching points (103) for branches (18) for supplying a respective part of the application elements (18) with spraying liquid and the decreasing inner diameter is defined such a) that a flow velocity of the spray liquid - at at least one branching point (103), which is located downstream of a first branching point (103), is at least as high as at the first branching point (103) and / or - does not decrease continuously in the section (110) and / or - does not fluctuate by more than 2 m / s, further preferably by no more than 1 m / s, between the first and last branch point (103); and / or b) that the section (110) between the first and last branch point (103) has a plurality of subsections (111-115), the inside diameters of which are each b1) smaller by 1 millimetre and / or by 2 millimetres compared to the upstream section, or b2) smaller by 1 nominal width, DN, and / or by 2 nominal widths, DN, compared to the upstream section.

5. Spraying device (10) according to one of the previous claims, wherein the ring line (100) is fluidically connected to a mixing chamber for mixing a plurality of spray liquids, preferably a main mixing chamber of a direct feed system (40, 50) of the spraying device (10) and optionally a pump (102) is arranged in the ring line (100).

6. Spraying device (10) according to claim 5, further comprising, a) a first dosing system (30), comprising a first storage container (31) for a first spray liquid (37) and a first dosing device (32); b) a second dosing or supply system (40), comprising a second storage container (41) for a second spray liquid (47), preferably clear water, and a second dosing or fluid supply device (42, 43, 45); c) a third dosing system (50), comprising at least one third dosing device (52, 53, 54) and at least one third storage container (51) and / or at least one container holder for detachably holding a third storage container (51), preferably a canister, for at least one third spray liquid (57), wherein the second spray liquid (47) can be supplied to the main mixing chamber (70) by the second metering or fluid supply device and the at least one third spray liquid (57) can be supplied by the at least one third metering device; and d) a control device (8) which is designed to control and / or regulate the first dosing system (30), the second dosing or supply system (40), the third supply system (50) and the application elements (13) for spraying and / or finely distributing the spray liquid.

7. Spraying device (10) according to claim 6, wherein a) the first metering device comprises a flow meter (33) and a pressure generating unit, preferably a pump (32), and the first reservoir (31) is preferably a main tank for a first premixed spraying liquid; and b) the second dosing or fluid supply device comprises a flow meter (43), a non-return valve (45) and a pressure generating unit, preferably a pump (42), and wherein the second reservoir (41) is a water tank; and c) the at least one third dosing device each comprises a dosing valve (54), a flow meter (53) and a pressure generating unit, preferably a pump (52), and the third storage container (51) is a smaller storage container for a plant protection agent compared to the second storage container.

8. Spraying device (10) according to claim 6 or 7, wherein the control device (8) is designed to control the second dosing or fluid supply device and the at least one third dosing device as a function of a desired mixing ratio of the second and third spray liquid (47, 57) in such a way that the second and third spray liquid (47, 57) are supplied to the main mixing chamber (70) on the input side in the desired mixing ratio.

9. Spraying device (10) according to one of claims 6 to 8 , wherein the third dosing system for providing different crop protection agents has a plurality of third storage containers (51) and third dosing devices assigned thereto, wherein the control device (8) for providing dosed quantities of crop protection agents is designed to control the third dosing devices in such a way that one or more of the crop protection agents are selectively supplied to the main mixing chamber (70) in a determinable dosing quantity.

10. Spraying device (10) according to one of claims 6 to 9, wherein a) the spray boom, and preferably each of the side arms, is divided into a plurality of subsections (19), wherein a plurality of the application elements (13) for spraying and / or finely distributing the spray liquid is arranged at each subsection (19) and each application element (13) is associated with exactly one subsection (19); and b) the spraying device (10) comprises a plurality of first mixing chambers (20; 20A), wherein one of the first mixing chambers (20; 20A) is assigned to each partial section (19), which is arranged upstream of the application elements (13) assigned to the respective partial section (19) and preferably on the partial section, wherein the first mixing chambers (20; 20A) are each fluidically connected on the inlet side to one of the branches of the ring line (100) and are also fluidically connected on the inlet side to a further ring line (35) and / or to a branch line to which the first spray liquid from the first metering system (30) can be fed.

11. Spraying device (10) according to claim 10, wherein the control device (8) for producing a mixture of the first spray liquid (37) with the second and / or at least one third spray liquid (47, 57) is designed to actuate the first dosing system (30) and to actuate the second dosing or supply system (40) and / or the third dosing system (50) in such a way that both the first spray liquid (37) and the second and / or third spray liquid (47, 57) are optionally supplied to all first mixing chambers (20; 20A) or a partial selection thereof are supplied with both the first spray liquid (37) and the second and / or third spray liquid (47, 57) in a definable quantity ratio.

12. Spraying device (10) according to claims 10 or 11, wherein a1) the first mixing chamber (20) has a plurality of distributor outlets (23) on the outlet side, or a2) a fluid distributor (28) is arranged downstream of an outlet of the first mixing chamber (20A) for dividing spray liquid into a plurality of partial flows, having a plurality of distributor outlets (23) for the partial flows, and b) the discharge elements (13) arranged downstream of the respective first mixing chamber (20; 20A) are each connected to one of the distributor outlets (23) via a discharge line (15; 16).

13. Spraying device (10) according to claim 12, wherein a) each of the discharge elements (13) is fluidically connected to one of the distributor outlets (14b) via a separate discharge line (15); or b) at least some of the discharge lines (16), preferably all discharge lines (16), each have at least one branching point (16a) which provides a plurality of line branches (16b, 16c), wherein in each case one line branch (16b, 16c) connects the branching point (16a) to a discharge element (13), wherein optionally the branching point (16a) is constructed in the manner of a Y-branch or in the manner of a T-branch.

14. Spraying device (10) according to claim 12 or 13, wherein the discharge lines (15; 16) are designed in such a way that the partial flows emerging from a first mixing chamber or the fluid distributor have essentially the same pressure drop and the same time delay on their separate partial flow paths from the first mixing chamber or from the fluid distributor to the respective discharge elements until the partial flows arrive at the respective discharge element.

15. Spraying device (10) according to one of the claims 12 to 14 , wherein those discharge lines (15; 16) which are connected to the same fluid distributor or the same first mixing chamber each have the same length, or wherein all discharge lines (15; 16) have the same length.

16. Spraying device (10) according to one of the claims 12 to 15 , wherein at least a part of the discharge lines (15; 16) a) is designed as hose lines and / or as flexible lines; and / or b) has a non-straight course, preferably a curved course, and / or c) has at least one section which is guided in the longitudinal direction (B) of the side arms (12) along one of the side arms and has at least one section which is guided in the vertical direction (V) along one of the side arms (12).

17. Spraying device (10) according to one of the preceding claims, wherein the application elements (13) are spray nozzles or nozzle sticks comprising spray nozzles.

18. Spraying device (10) according to one of the preceding claims, wherein the spraying boom (11) is arranged on a carrier vehicle (2) so as to be movable about a pivot axis (A) extending in the direction of travel, directly or indirectly, and / or wherein the two side arms (12) are each connected to a centre part (11a) of the spraying boom (11) so as to be rotatable about a vertical pivot axis, and wherein each side arm (12) has segments which are pivotable relative to one another, which are pivotable relative to one another about upright axes and which are pivotable relative to one another in a plane arranged perpendicular to the direction of travel of the agricultural distribution machine.

19. Agricultural field sprayer (1), comprising a spraying device (10) according to one of the preceding claims, wherein the field sprayer is, for example, a self-propelled field sprayer (1) or a field sprayer towed by means of a towing vehicle or a field sprayer attached to a towing vehicle.